WHATEVER HAPPENED TO AM RADIO? ^ 48783 wctnancs rECHNOLOGY - VIDEO - STEREO - COMPUTERS - SERVICE BUILD THE LAWN RANGER Let a robot take the work out of cutting your lawn! BUILD R-E's DIGITAL Add a high-tech look to any car S2.S0 U.S. $2.95 CAN I GERNSBACK i*?^^:^- Our Telephone Line lets you restrict incoi... outgoing calls, and lots more! MICROWAVE TECHNOLOGY Early attempts at microwave generation tjxnMX CflR-Rr SORT xj. am 75045GNRR5165MD93 D9 34 RE FLUKE AND PHILIPS - THE GLOBAL ALLIANCE IN TEST & MEASURE MEN FLUKI PHILIP! The new 80 Series is a digital meter, an analog meter, a frequency counter, a recorder, a capacitance tester, and a lot more. It's the first multimeter that can truly be called "multi" ...not only standard features, but special functions usually limited to dedicated instruments. Plus, innovations only Fluke can bring you. Like duty cycle measurements. Or recording ttie minimum, maximum and average value of a signal. Orttie audible MIN MAX Alert'" that beeps tor new highs or lows. There's even Fluke's exclusive Input Alert™, that vifams you of incorrect input connections. And a unique Flex-Stand™ and protective holster, so you can use the 80 Series almost anywhere. Make sure your next multimeter is tmly multi. Call today at1-800-44-FLUKE, ext33. FROM THE WORLD LEADER IN DIGITAL MULTIMETERS. FLUKE 83 FLUKE 85 lEsl. audibte continuity, \n , FWatiffi, (mtffiliv! twist FLUKE 87 Wts.c4irn5, amps, diode sapaotante. Touch Hokf ■quency and duty cycH:. rmttiFltJ Stand- S199- S23S' SS93- 0.3% base do accuracy StrtiJcV AiBlod bjijudii 1 mom Tliree year wjiranly 0,HHua; dc itoirscy Anjlos tBiyratli S ZOHT TlirH year warranty [),flt bisic de areuwv WkHiatV Higti rcHjUitiwi anUog Bontti Trusmsac 1IT15 PEAK MIN MW JWigit™* Back III disolay Three yeat *arranitif 'SuooestedU.S, listpfKe Tlie new Fluke 80 Series shown actual siie John Fli*s MHj, Co., Inc, ftO, Boi 3090 WSZSOC. Everett, IW SaMS U,S.: ; 1l«-Fm CIRCLE 121 ON FREE INFORMATION CARD FLUKI September 1990Em mcinjiiScs^ Vol. 61 No. 9 33 RE'S VOCAL STRIPPER Filter out the lead vocals from your favorite recordings, and dub in your own voice! Terry L. Weeder 37 TELEPHONE LINE CONTROLLER Block out unwanted incoming and outgoing calls, and more! Mordechai Saad 53 THE LAWN RANGER: PART 4 It's time to get the lawn mowed! Raymond Rafaels 61 RE'S DIGITAL DASHBOARD Build an array of digital gauges for your car. Ross Ortman KyKHii.'iiiRiilT DATA DISKS KICH SPEED DEVICE SELECTION FOR THE 90S 47 DATA DISK: HIGH-SPEED DEVICE SELECTION FOR THE 'SO'S Electronic data processing makes it easy to find the right components for your applications. Ed Prestwood 68 INTRODUCTION TO MICROWAVE TECHNOLOGY The focus is on early RF oscillators. Joseph J. Carr 71 AM RADIO What does the future hold for the AM band? Gerry L. Dexter ■H'lullil^yHlK BUILD RE'S DlGiTAL DASHBOARD 88 COMPUTER CONNECTIONS Windows 3.0 and ToolBook Jeff Holtzman EEmm 6 VIDEO NEWS What's new in video, David LachenbrucK 16 EQUIPMENT REPORTS Hewlett-Packard's 48SX scientific calculator. 83 DRAWING BOARD Let's start on control circuitry. Robert Grossblatt 75 HARDWARE HACKER Thoughts on perpetual motion. Don Lancaster 81 AUDIO UPDATE An Audio Engineering Society conference report. Larry Klein 00 Advertising and Sales Offices 100 Advertising Index 7 Ask RE 97 Free Information Card 12 Letters 101 Market Center 26 New Lit 22 New Products 4 What's News m •V -^ m S to o ON THE COVER g z o I- O UJ _I LU Q a < WHATEVER HAPPENED TO AW liADlD? Eli 'gtaitiB ^EEtrangifs. If there's a common thread that runs through the three seemingly disparate stories highlighted on this month's cover, it would have to be the notion of control — whether at home, at work, or at play. Our Tele- phone Line Controller Csee page 37) is an obvious example, allowing you to block out any calls, either incom- ing or outgoing, that you deem un- desirable. If your work (or your hobby) involves electronic design, the article on data disks that replace bulky, inconvenient cross-reference books will show you how to take bet- ter control of your valuable time. Turn to page 47 to find out how to speed up the device-selection process. And, just forfun, our Lead-Vocal Zap- per (see page 33) gives you some control over your stereo records, by letting you replace the lead vocal with your own voice. COMING NEXT MONTH THE OCTOBER ISSUE GOES ON SALE SEPTEMBER 4. BUILD A ROCKET ALTIMETER Get a second-by-second playback of the flight of model rockets. LASER-JET MEMORY CARD Add memory to HP's LaserJet printer, for a fraction of HP's price. SOME TV SETS CROSS THE BENCH Case histories in TV service have some lessons to teach. MICROWAVES: PART III A look at magnetron tubes. As a sarvice to readera, RADJO.EL&CTRONICS publishes available plans or information relating to newsworthy products, techniques and scientific and techt^clogical developments. Because pf possible variances in the quality and condition of fnaterials and workmanship used by readers. fliVDIO-ELECTf^ONICS disclaims any responsibility for the safe and praper functioning of reader-huilt projects t34sed upon or tmrr plans or information published in this magaiine. Since some of the equipment and circuitry descrihad in RADIO-ELECTROMIC& may niate to or be covered by U.S. patents. RADIO-ELECTBONICS disclaims any liability for the Infiinaement of such patents by the maVing. using, or saltirvg of any such equipment or circuitry, and suggests that anyone interested in such prajects consult a patent attorney. RADIO-ELECTRONICS, (ISSN 0033.7862) September 1990 Putjiished monthly by Gernsback Publications. Inc. EOO-B Bi- County Boulevard. Farmingdale. MY 11735 Second-Class Postage paid at Fanmingdsle. WY and additional mailing offices. Second-Class mail registration No. 97A2 authorized at Toronto. Canada. One-year subscription rate U.S.A. and possessions $17.97. Canada S23.97, aM other countries $26.97. All subscription orders payable in U.S.A. funds only, via international postal money order or checl^ drawn on a U.S.A. bank. Single copies $2.50. <^ 1990 by Gernsback Publications. Inc. All rights reserved. Printed in U.S. A POSTMASTERr Please send address changes to RADIO-ELECTRONICS. Subscription Depl.. Box 55115. Boulder, CO 80321-5115, Astamped self-addressed envelope must accompany all submitted manuscripts and/or artwork or photographs if their return Is desired should they be rejected. We disclaim any responsibility for the loss or damage of manuscripts and/or artwork cr photographs while in our possession or otherwise. tlEctmrnES^ Hugo Gsm^ack (1 864-1967} bundar M. Haryey Gemsbftck. flditor-in-cihiaf,. emefitu^ Larry Stockier* EHR GET. iQditi)r-m-c^i«f find publisher EOrrORlAL DEPARTMENT BHan C, Ffinton, adttar Marc Spiwah, assaciate edrt&r DanieT Goodman^ technfeal editor K^m DunlA^vyf assistant technical entributing editor Richard D. Fitch contributing editor Kathy Campbdll, editorial assistant ART DEPARTMENT Andre Duxant, art director Injae Lee, illuBtrator RusselE C. Truelson, illustrator PROOUCTtOlM DEPARTMENT Ruby Mr Yee, prDduction director Janice Bo^, editorial pnoductiofi Karen S. Tucker advertising production Rbrcella AmoroBO pitiduction assistant CIRCULATION DEPARTMENT Jacqueline P. Cheese bo re Circulation director Wendy Alanko circulation analyst Theresa Lombardo circulation assistant MIcftele TorrillOt reprint bookstore Typography by Mates Graphics Cover photo by Diversified Photo Services Radio-Electronics is indexed in Appfffed Sc/ertce S Techno fogy Mdex and R^&d&fs Guide to Periodicst Uter- atune. Microfilm & Microfiche editions ere available^ Contact circulation depart- ment for details. Advertismg Sales Offices listed on page 95, Radio -Electronics Executive and Administrative Offices: 1-516-293 3000, Subscnbor Customer Service: 1-600-2B8-06S2, Order Entry for New SuhscHbers: 1 S0O-e99-7t3d. M'A ^ Ttie Auflii Bureau ol Cifculalran AT $299.95, NO CITHER DESIGN WORKSTATION GIVES YOU SO MUCH FOR SO LITTLE. PR07D BOARD BRAND Function Generator ..sine/square/triangle ...plusTTL Large Breadboarding area tiolds 24 ICS ...2,500 tie points Triple Power Supply ... +5V fixed, plus two variable 5-15V 8 TTL Logic Probe Indicators Audio Speaker Two Digita Pulsars Two BNC Connectors for oscilloscopes and counters OVER $600 WORTH OF WORLD CLASS TEST EQUIPMENT FOR UNDER $300! Here's PB-503, the total design workstation. It lias everything! Instrumentation, including a func- tion generator with continuously variable sine/square/triangle wave forms — plus TTL pulses. Bread- boards with 8 logic probe circuits. And a Triple Power Supply with fixed 5VDC, plus two variable outputs ( + 5 to 15VDC and - 5 to 15VDC). Throw-in 8 TTL compatible LED indicators, switches, pulsers. potentiometers, audio experimenta- tion speaker.. plus a lifetime guar- antee on all breadboarding sockets! You have everything you need right there in front of you! PB-503 — one super test station for under $300! Order yours today!! Call toll-free for details 1-800-572-1028 GLOBAL e SPECIALTIES CIRCLE 189 ON FREE INFORMATION CARD m m 3] A016 Global Specialties. 70FultonTerrace.NewHaver,CT06512. company Telephone: (203) 624-3103. ft Interplsx Eleclronics, 1990. ^ All Global Specialties breadboarding products made in USA. to ProloBoard is a registered trademark o( Global Specialties J!^^^-*-^t=^'''^- A review of the latest happenings in electronics. Ultra-pure silicon crystal Scientists at the Westinghouse Science & Technology Center (Pitts- burgh, PA) have produced a silicon crystal that is four times purer and significantly larger than any pre- viously reported silicon material. Im- purities comprise only a few parts in 100 trillion, compared to more than 10 parts in 100 trillion previously re- ported for one-inch diameter silicon crystals. The 22-pound cylindrical structure — called a boule — is more than a yard long and has a diameter of just over 3 inches. Its larger size makes it more practical for use in microelectronics circuits and de- vices. Crystal boules are sliced into wafers on which microelectronic cir- cuits and power semiconductor de- vices are fabricated. The West- inghouse crystal, which its de- velopers believe to be the purest silicon crystal ever made, is expected to play an important role in the man- ufacture of infrared detectors for space, defense, and environmental applications. The ultrapure silicon crystal was grown in Westinghouse's float-zone crystal-grov/th facility, the largest float-zone furnace in the U.S., o o _i LU 6 < IN TEKTRONiX'S PLASMA-ADDRESSING PROCESS, the liquid-crystal material and a protective dielectric layer are sandwiched between two sheets of glass; the upper sheet contains the data electrodes patterned from the transparent indium-tin-oxide conductors and the bottom sheet provides channels that contain the plasma gas with two electrodes per channel. WESTINGHOUSE TECHNICIAN Don Nebel holds a single-crystal boule of sil- icon, believed to he the purist and largest ever produced. which can be adapted to produce boules up to four feet long and five inches in diameter. Plasma-addressing approach for high-resolution LCD's Tektronix researchers in Beaver- ton, Oregon, are developing a new plasma technique using a plasma switch to address the active matrix of a liquid-crystal display. Intended as an alternative to silicon thin-film tran- sistors CTFT's), which are successful in small, full-color displays but are dif- ficult to manufacture in a large array to address more than a million ele- ments, the new technique could sig- nificantly reduce the number of row drivers and make the displays easier to manufacture. The plasma technique uses gas- fiiled channels to address a variety of twisted-nematic and polymer-dis- persed liquid crystals. Confined ionized gas acts as an electrical switch; It conducts in an ionized state and becomes nonconductive when de-ionized, The degree of con- ductivity is determined by the number and mobility of the carriers in the gas. Tektronix says that the conductivity range of the gas (between con- ducting and nonconducting states) can be ten orders of magnitude. The/ have developed a plasma switch to take advantage of that property. The plasma switch is a three-termi- nal structure that uses a probe elec- trode on one terminal to alter the conductivity between the other two. A single switch can replace a whole row of silicon-based TFT's. Results of the initial demonstra- tions have been promising. 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(PuMithtrj' pricm stwwn) 34 £. l_l I I -^^- AN'/ PNP r/(AMi,i- TO/?, Sse T£KT COMMON A//OD£ FIG. 1— THE 4511 IS DESIGNED to directly drive a common- cathode display but, by adding a transistor as shown here, you can use it to drive a common-anode dis- play. member the rule: Better to underrate parts than to overrate them. You may find the schematic shown in Fig, 2 to be useful as well. Even though the 4511 can directly drive a common-cathode display, it has (as do all display drivers) a maximum cur- rent that it can deliver at the outputs. CO m ■0 m DO o That causes a problem when you try to drive really big displays or even incandescent bulbs. Putting a transistor at the output switches the burden of powering the display from the chip to the transistor. If you need more current just add a I / / -V- Ai/y f4PN Tfy(f/S!S- co/yfMOM C4maO£ FIG. 2— EVEN THOUGH THE 4511 can di- rectly drive a common-cathode display, you may have to add a transistor to the output. That allows you to drive really big displays or even incandescent bulbs, chunkier transistor. The solution is really that simple. Of course you have to keep in mind that the 4511 is a CMOS part and it can't be expected to deliver enough current to trigger heavy-duty tran- sistors. If you ever want to do some- thing like that, you'll have to build an intermediate transistor stage to bring the output of the 451 1 up to the level of the output transistor. But, for driv- ing standard common-anode dis- plays that typically want a maximum of about 20 mA per segment, that circuit should solve the problem with- out any difficulty, DIGITAL AMPLIFICATION I've built a circuit to accept data from a temperature sen- sor but tKe input signal is a bit too low to go through my A-to- D converter. I don't want to have to add analog circuitry to the design so is there any easy way to amplify the incoming signal with digital IC's? — A. Dolan, Belmar, NJ Once upon a time there was no way to do that, but your problem can be solved with the addition of a couple of CMOS inverters. You may have to add an IC to the board but, if you've got three spare inverters around, you can use them. The 4049 is a good choice for this application since it can handle higher power levels and is perfect to use if you've got to do any sort of voltage \h 'IN \.ot — -VA — /OME& FIG. 3— The 4049 CAN HANDLE high power levels and is perfect for any sort of voltage translation. The amplifier will give you a gain of 10 with an input impedance ofoveramegohm. translation. As shown in Fig, 3, the amplifier will give you a gain of 10 with an input impedance of over a megohm. It doesn't require any kind of special layouts and should work without a problem. If you add a 4049 remember to do something with the unused inverter inputs. Although you can easily build the circuit, and it will do the job, I don't understand why you don't build a small single-transistor amp to do the same job, I don't know what the characteristics of your input signal are but I'm sure you could easily de- sign a simple transistor amp to pro- vide the gain you need. R-E o o cc 1- o UJ o o < Cut Yaur Video Servicing Time by 54%* $3,495 Patented '"""^S^^* With The Market Proven VA62A Universal Video Analyzer^ Are you finding it tough to service today's hi-lech VCR and TV circuits? SuccesstuI video servicers have told us that, to them, the new technology meant lost profit and troublesfiooting grief until Itiey tried ttie VA62A's time tested, functional analyzing methods. The VA62A cuts servicing time and increases profits . , . " 'Based on a nationwide sjrvey of users who reported an average time savings of 54% compareci to their previous test equipment. You can prove it to yourself, in your shop, absolutely risk free — and share in the profits successful video servicing can bring. Call 1'800-SENCORE (Tx-sejay and ask about our exclusive VA62A instrument evaluation program, Tech-Tape Video Preview and FREE full line color catalog are also available. ® 32O0 Sencore Drive, Sioux Falls, SD S7107 100% American Made CIRCLE 180 ON FREE INFORMATION CARD Discover Your Career Potential In The Fast Growing Field Of High-Tech Electronics! CIE Gives You The Training You Need to Succeed... At Your Own Pace...& In Your Own Home! If yoi're anxious to get ahead ...and build a rea/ career... you owe it to yourself to tind out about the Cleveland Institute of Electronics! CIE can help you discover your career potential in the fast growing field of high-tech electronics. A career that will challenge and excite you every day.. .reward you with a powerful feeling of personal accomplishment... and deliver a level of financial security you may have only dreamed of before! As the leading school in home-study electronics, CIE has helped over 150,000 students in the U.S.A. and over 70 foreign countries get started in this exciting field. To find out how CIE could be helping you.. .read on. .then send for a CIE catalog TODAY! A Growing Need For Trained Professionals! Ttie career opportunities shown here are only a few of the challenging, high- paying careens you could enjoy as an electronics technician. You could he the 'brains" behind the scenes of an exciting TV broadcast... trouble-shoot life-saving medical equip- ment... design exotic new aeronautics systans... CI E's job-oriented programs offer you the quickest possible path to the career of your dreams! And CIE also features military and union re-training, to build on what you already know. Dozens Of Fascinating Careers To Clioase FromI Even if you aren't sure which career is best for you, CIE can get you started with core lessons applicable to alt areas of electronics. As you advance, CIE makes job opportunities available to you through the bimonthly school papw, The Electiw Da fa Communications Auiomotive Electronics Qcfflfa ^^^^^Sii ^^3B^^^^^V' \^^^D ^^^Ihs^lBBIHI llli HBSb^SL^kS Ai/iomcs Compater-Assistmi H/tanuiacturing Constmier Electronics Mliitary Electronics Personal Training From A Renowned Faculty. Unlike the impersonal approach of large class- room study, CIE offers you one-on-one instructional help 6 days a week, toll-free. Each CIE lesson is authored by an independent specialist, backed by CIE instructors who wo[1< directly with you to answer your questions and provide technical assis- „„„ tance when you need it. Practical Training... At Your Own Pace. Through CIE, you can train for your new career while you keep your pres- ent job. Each course allows a gener- ous completion time, and there are no limitations on how fast you can study. Should you already have some electronics experience, CIE offers several courses viriilch start at the intermediate level. "State-Of-The-Art" Facilities & Equipment. In 1969, CIE pioneered the first elec- tronics laboratory course, and in 1984, the first Microprocessor Laboratory. Today, no other home study school can match CIFs state-of-the-art equipment. And all your laboratory equipment is included in your tuition cost. There is no extra charge— ifs yours to use virile you study at home and on the job after you complete your courae! Earn Your D^ree To Become A Professional In Electronics! Every CIE coui^ you take eanis you credit towards the completion of your Associate in Applied Science O^ree, so you can work towards your degree in stag^. And CIE is the only school that avrards you for fast study, which can save you thousands of dollars in obtaining the same electronics education found in four-year Bachelor's Degree programs! Write for details today! Send For Your Catalog Today! ^ ,0 j C IE World HeadquartBrs Clweland Institute of Electronics, Inc. 1 1776 East 17th St., Cleveland, Ohio 4411 4 1^1 ARE-174 r^ -<^ ''OlVfE St'^ ■^ -^t n YES! Please send me your imjppendent study catalog {For your converience. CIE will have a rBpresaitative contact you— (here Js no oWJgaf/bn.J / PtintNsne . .■^ rAddEES . Apt! Gity/State/Zip . Area Code' Phone No 1 en I f" I -D I m il IS •^ x-~ i^ ..5S I Che* hex for G.I. Bill bulletin on educationai benefits: o veteran a Active Duty I Mail This Coupon Today! ^,, ,,J I 11 LETTERS Write to Letters, Radio-Electronics, 500-B Bi-County Blvd., Farmingdale, NY 11735 o < DESOLDERING DEVICES I'm writing in response to Mr Per- due s letter that appeared in the May 1990 issue of Radio- Electronics. (He was responding to a previously published letter that concerned IC re- moval.) I take extreme exception to his general statement that the use of desoldering braid is "the only one approved by government organiza- tions." I work for a government or- ganization that regards the use of desoldering braid as a last resort! As a matter of fact, the U.S. government approves several methods of both soldering and desoldering compo- nents on printed-circuit boards. One of the appnaved methods of desoldering IC's is to use a motorized vacuum device, such as a "Pace Kit." Of course, that method requires spe- cialized training, and the cost of such a device would be prohibitive to the average home technician. Next on the list is the mechanical vacuum de- vice, commonly known as the "solder sucker." That item is available at most electronics parts stores. To use it, simply cock it and then heat the joint to be desoldered with a low-wattage iron. As soon as the solder begins to flow, place the tip of the solder-sucker vacuum over, and in physical contact with, the joint, and press the trigger button. When the solder sucker has tripped, remove both the iron and the vacuum immediately. Check the joint to make sure that all the solder was removed. If not, simply repeat the procedure. A few words of caution: First, use a low-wattage (10-25 watts) soldering iron at all times, to prevent overheat- ing the IC and causing internal damage. A temperature-controlled iron is even better Next, when work- ing with IC's — particularly CMOS types — always use a ground strap (a metal wrist strap with a detachable ground wire) and connect its wire to ground. That will prevent the dreaded static discharge from destroying your IC or other components on the circuit board. If you don't have a ground strap, discharge yourself on a cold- water pipe or some other type of ground before starting work. Finally use a small-diameter pointed or wedge tip on your soldering iron. That helps to heat only the area intended to be heated, and will prevent circuit- board runs from being lifted. As a last resort, Mr Perdue's deso- ldering braid method, as described in his letter, will work. Using either the solder-sucker or the solder-wick method will take some practice, and I, too, would recommend that the novice practice on a junk circuit board to get a feel for either method. That lessens the chance of accidentally destroying a good circuit board or its components. STEVEN E. SWENTON Glen Burnie, MD I/O CARD INPUT I was intrigued by Mark Hanslip's article, "Build This Experimenter's 1/ O Card (Radio-Electronics, June 1990). I find it amazing that the 8255 PPl, an LSI IC introduced about a decade and a half ago for 8080 systems, is still being used in new designs. I disagree with the author's state- ment about Port B when POrt A is initialized for mode 2 operation: "Port B is not used at all." Although Port B cannot be initialized for mode 2 oper- ation, it is far from useless. Port B, independent of Port A's mode of op- eration, can still be used in either mode or 1. One last thing: The pins of Port C that are not commandeered for use by Ports A and B (when operating in modes 1 and/or 2 for handshaking) are available for use as input or output lines. JAMES KOVAR Lincoln, NE Fig. 1 goes here Mr. Kovar has a point. The chart that be provided (Fig. leaves a blank where Port B would be located in relation to mode 2. As t have never needed to use mode 2, the situation has never come up. Thanks, Mr h^var for clearing up that anomaly. Mode Definition Summary PAo MODE M0DE1 IN OUT IN OUT IN OUT IN OUT PA, IN OUT IN put_-. PAj PA3 PA, PA5 PAe i PA, IN IN OUT n OUT OUT OUT PBo IN OUT \H OUT PB, IN OUT IN OUT PBj IN OUT Ok , IN OUT PB3 IN OUT IN OUT PB, IM OUT IN OUT PB5 IN OUT IN OUT PBs IN OUT IN OUT PB? IN OUT IN OUT PCo IN OUT INTRg INTRa PC, IN OUT IBFb OBFo PC; IN OUT STBb ACK PC3 IN OUT !NTR, INTFt PC, IN OUT STB^ I/O PCs IN OUT IBF, 1,'0 PCe IN OUT I/O ACK, PC, IN OUT I/O OBF, MODE 2 GROUP A ONLY I/O I/O I/O I NTR a STB;^ IBFa ACK^ OBFa 12 The 8255 is truly a great device. It allows for software-configurable hardware. In the past. I have designed interfaces using the 8255 for Apple, Radio Shack. Timex, Decision Mate V, and S-WO computers. MARK HANSLIP TUBE TALK While browsing through some old issues of Radio-Electronics I came across several letters in the December 1988 issue that dealt with tubes from Russia being imported into this country, and it brought to mind an experience 1 once had. At a government auction (where I purchased a couple of pallets of test gear), a well-dressed fellow was bid- ding on items that I considered to be just so much junk. (After all, they were all full of tubes.) He was picking the stuff up by the ton, while hardly anyone else there showed any inter- est in it. When I asked him about his pur- chases, he told me that he and two other ex- Air-Force pilots had formed their own business, hie went around the country to all the government auctions and routed his purchases to a port, where they were loaded onto a ship and sent to Taiwan. One of his partners headed a group there that dismantled all the gear, "even salvag- ing the pan-head screws." The tubes, considered "choice" items, were re- routed to Europe where they com- manded a very high price. (The third ex-pilot handled the European end.) When I saw those letters about Russian tubes, I couldn't help but wonder: "Does it seem likely that a lot of our own tubes are coming back at us — re-labeled?" RUSSELL RIESBERG Weimar, CA ALL ABOUT THX SOUND In Josef Bernard's June 1990 arti- cle, 'All About Surround Sound," he gives the mistaken impression that "THX" is ".. just quality control for movie sound ..." The THX Sound System was developed by Tom Holman for the main sound-mixing theater at Lucasfilm. It consisted of particular speakers mounted in a special construction behind the screen along with a crossover de- signed with those elements in mind. Its sound was amazing. Since the vast majority of sound systems in cin- emas were outdated, and few could CLEANING/MAINTENANCE/REPAIR EARN UP TO Si 000 A WEEK. WORKING PART TIME FROM YOUR OWN HOME! 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Sugg, Retail: compatible, ^ ^^ ■ .42 mm dot pitch, q>^,300.UU •256 colors. ■■HJJj=IH=J.I!^Jl Resolution: ^. Af\r%QQ 640x480. JpT /I CI CI MM Dim.: 14.72"W ■ Resolution: a .j m ^^ ^% 640x480. $T /I QQ ! ■ Dim.: 14.72"W I ^W^^ X 12.40"H Item No, B-2213-14357S X 1 5.64"D. Insured Ship/Hand.: $49.00 FOR FASTEST SERVICE CALL TOLL FREE 1-800-729-9000 ^^^r fc^^ DAMARK INTERNATIONAL. IKC. 7101 Winnerka Av9. ^3.. Minneapolis, fAN 55423-1 $19 Custonner Service ■612-531-008? Ptea^e rush me; Cordata Compuief (s) @ Si 499.99 eacfi, plus $49.00 s^h each. riem No. B-221 3-1 43575 MN res. add 6% sales tax. HSIT\S_ Arirfrpw r^^Y eir^lB ^ip □ Cr«Oi(MO C«nJNo, nvis* n Masler Caia D aisariv E«p. Oale / . Ph # ( 1 Sbnaturs Cof^ight 1990 OAMARK rnternalicKiat, Inc. AH rlflhUs rosefVKl. DELIVERY TO 48 U.S. STATES OhJLV handle the dynatnics of a Lucasfilm movie, the THX system was licensed to theaters. As a former "THX engi- neer" 1 was involved in some of the first installations. The theater had to meet certain acoustical criteria con- cerning the overall noise level, rever- beration time, and more. If a theater couldn't meet those criteria, it could not get a THX system. If it could, the theater was shut down vyhile the screen was removed so that the THX wall could be built and the speakers installed. The THX crossover was put in along with amplifiers that also had to meet certain standards. Thus, if a movie patron went to a THX theater, they would be listening to the same system that the sound was mixed on. The "quality control" consisted of periodic checks of align- ment. As for the letters "THX," I re- member that Tom Holman designed the crossover or X-over ROBERT HUGHES San Francisco, CA Since Mr. Hughes was thete. and I merely got my information second- hand, t will have to bow to his exper- tise — and thank him for the additional background on THX. My original point Get A Complete Course In ELECTRONIC ENGINEERING 8 volumes, over 2000 pages, including all necessor/ moth and physics. 29 examinations to help you gouge your personal pro- gress A truly great ieorning experience. Prepare now to take advan- tage of tine growing demand for people able to work at the engin- eering level. Ask for our brochure giving complete details of content. Use your free information card num- ber, or write us directly. $99.95, Postage included. Satisfaction guaronteed or money refunded. r\AA/ IJ Banner Technical Books, Inc. 1203 Grant Ave. Rockford, IL 61103 is still valid, however THX is just a special case of Dolby Steneo, and one should not expect to be able to rent or purchase videotapes or laser discs recorded using a "THX pro- cess. " JOSEF BERNARD CHAOS vs. CLASSICAL PHYSICS While sitting in my den the other day, reading James Gleick's fas- cinating book called Chaos, I took a break to thumb through the new is- sue of Radio-Electronics. In the "Letters" column, I read with as- tonishment the letter from Jon Rolph criticizing Don Lancaster's ideas about the size of the brain's computer and its relationship to other computers. I'm astonished because of its parallel to one of the main themes in Chaos. The painful, "feet-of-clay" conservatism that has hampered the emerging super science of chaos for nearly a de- cade appears from Mr Rolph's let- ter to have infected computer science as well. Chaos's pioneer physicists and mathematicians, men like Mandelbrot and Feigen- baum, literally risked their careers by publishing the new and radical ideas embodied in chaos and fractal geometry. Still considered a re- negade science by many, those new ideas have rattled the rusty old cages of many disciplines, Mr, Rolph's suggestion that any radical departure from the classical under- standing of a science might "set us all back a few paces" is the very kind of thinking that has plagued the advancement of chaos as a scien- tific discipline. The only way we pro- gress in our thinking is to make those conceptual leaps that go beyond proven classical knowledge to provide the theory and hypoth- esis for the next generation to prove or disprove. Condemning Don Lancaster and Hardware Hacker for allowing to appear in print aberrations such as the idea of computer systems "waking up" or four-gigabit brains is not an argu- ment against the fear of new tech- nology, as Mr. Rolph suggests, but a demonstration of that very fear. I am writing this letter on a desk- top computer that itself has nearly four gigabits of memory. It is my personal workstation, and I consid- CIRCLE 67 ON FREE INFORMATION CARD er it to be quite "awake" In many respects. It clearly has a personality of sorts. It expects nny interaction with it to follow certain behavior pat- terns and complains if I deviate from them. It has a strong instinct toward self-presen/ation. It stops and asks me if I'm sure before it allows me to reformat its disk memory. Other computers, those that do real- world control applications, are aware of at least some of their sur- roundings and are able to interact with them. That all suggests a form of awareness that has obviously es- caped Mr Rolph. While he waits for his network to wake up and assault him, Heinlein style, he is sleeping through a revolution in computers. I applaud Don Lancaster for his imaginative thinking; I have been a follower since the days of the "TV Typewriter" I also applaud Radio- Electronics, for providing a forum for him and other innovative thinkers. PETER A. BARNES Cincinnati. OH SHARING FREEWARE I have thoroughly enjoyed each of the articles in Radio-Elec- tronics; it is one of the few pub- lications that I actually read cover- to-cover It is also one of the few magazines in my field that contains something I can share with every- one on at work, at any level of exper- tise. I'm not saying that I agree with everything in its pages, but that it promotes discussion on the art of electronics. One thing I'd like to share with other Radio-Electronics read- ers is that Linear Technology Cor- poration is supplying — for free — an improved freeware pspice version from Micros im. It provides 28 op- amp models, which model benched data. I don't like to keep lots of inventory in my lab at work or my home workshop. This excellent sim- ulator lets me be certain a circuit does what it should, and if a circuit doesn't work (i.e., an amp oscil- lates). I can quickly work out the bugs. 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CIRCLE 101 ON FREE INFORMATION CARD g z o cr h- o UJ _l 111 o < IT HP's latest scientific calculator is at the head of itsjzlmS' CIRCLE 13 ON FREE INFORMATION CARD September is back-to-school time for many of tomorrow's engineers. It's the time that many students — along with those of us who haven't been students for some time — start looking for the per- fect scientific calculator. We may have found that perfect calculator the HP 48SX from Hewlett Packard (In- quiries manager, Hewlett-Packard Company. 1000 N.E. Circle Blvd.. Corvallis, OR 97330). The calculator, introduced earlier this year, boasts more than 2100 functions. It allows equations to be entered the same way they would be written, and an impressive array of graphics functions lets you plot the equations. An RS-232 interface is available as an option, and an infrared interface is also offered. The stan- dard built-in memory consists of 256K of ROM and 32K of RAM. but plug-in cards allow you to expand memory to 51 2K of ROM and 288K of RAM. Using the 48SX Without question, the 48SX\s the most powerful and advanced hand- held calculator available. Getting ac- cess to all of that power is not alwrays easy because some functions don't work the way you would intuitively expect. Also, the larger than 800- page CD manual, while excellent on specifics and details, does not give a good overview of what the calculator has to offer (We would recommend stopping by an HP dealer who should have a demo disk or RAM card that does provide a good overview.) The HP 48SX offers several im- pressive and important features. Its EquationWriter application allows equations to be entered as you would write them. Its graphics capabilities integrate calculus and graphics func- tions to find roots, minima and max- ima, slopes, area under a curve, etc, A unique automatic unit management feature converts unlike units of mea- surements CI 48 different units in 16 categories such as force and energy) automatically. An equation-solver function allows you to find the numer- ical solution to an equation without isolating the dependent variable. For example, if Ohm's law was entered as an equation, you could enter the nu- merical values of the known varia- bles, and the calculator would solve for the missing one. The calculator's keyboard contains 49 keys, most of which perform three or four different functions. Each key's primaiy function is on the keyface, while its secondary functions are shown in orange, blue, and white leg- ends around the key. and are ac- cessed by using the appropriate shift key. Some secondary functions (lower-case letters. Greek letters, and special characters), which are not shown on the calculator's face, ans also available. The top row of keys are "soft" keys — they take on the function shown on the bottom, menu line of the display. Most mathematical operations are performed by entering arguments on to the stact< (which is a last-in, first- out sequence of storage locations) and then executing commands to ma- nipulate the stack contents. Although the display can show the contents of up to four stack locations, the actual stack size can be much larger, and is A SERIAL INTERFACE KIT is available as an option to allow you to link the cal- culator to a PC or Macintosh so you can take advantage of the computer's storage, printing, and display capabilities. 16 PLOT THE EQUnTION y y bMs\^mmw^\^\AM^A\m^Wsxi ZOOM IH T H * 1 h'*-' » — ► / pnrni ^a3l^!^ wgniH .M ;i mm^ Wsxm SLOPE FOUND +7"*- ^ fL0P£:3J3(>3531< ^zizr A 151 LOCAL r-1IHinUM FOUND EI-ITftM: (E.-3.HlI0B9(>ae55 THE HP 48SX INTEGRATES GRAPHICS AND CALCULUS (unctions to automat- ically find roots, intersections, minima and maxima, derivatives, and the lilte. limited only by available RAM. As you might guess, the calculator uses reverse Polish notation to solve equations. For example, to find the sum of 2 + 2, you would enter both addends on the stack, and then per- form the addition. The keystrokes would be: "2 2 + ," The number 4 would appear at the top of the stack. Understanding the stack is the key to understanding how to use the cal- culator. Even when you enter an equation "as you would write it," you cannot solve it, plot it, or do anything else with it until you put it on the stack. Unfortunately, when you do move the equation onto the stack, it loses its "textbook appearance" and takes on a form more common to computers. That can be disconcert- ing and confusing until you get used to it — and the learning curve can be a steep one if you've never had any similar experience. You can name an equation that is stored on the stack. That's helpful because the name can be used to identify an equation that might other- wise be very difficult to recognize once it's moved to the stack— es- pecially if the equation contains inte- grals. While the 48SXs built-in functions are impressive, it's important to re- member that the calculator can be custom programmed through its built-in programming language. And we've barely mentioned the cal- culator's built-in functionsi The 48SX can handle all sorts of operations with arrays and matrices, statistics, algebra, calculus, logical operations, vectors, complex numbers, and more. It can also produce eight dif- ferent types of plots from function plots to histograms, and from scatter plots to polar and parametric plots. Be an FCC LICENSED ELECTRONIC TECHNICIAN! No costly School. No commuting to class. The Original Home-Study course pre- pares you for the "FCC Commercial Radio- telephone License". This valuable license is your "ticket" to thousands of exciting jobs in Communications. Radio-TV, Micro- wave. Computers. Radar. Avionics and more! You don't need a college degree to qualify, but you do need an FCC License, No Need to Quit Ybur Job or Go To School This proven course is easy, fast and low cost! G UARANTEED PASS — You get your FCC License or money refunded. Send for FREE facts now. 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SeyiCOnDUCTOiffi. complete the DC/AC videos and you're ready to learn how semi- conductor devices are made, plus the principles of discrete devices, integrated circuits & optoelectronic devices, EV-3103-A, BBHROliC CRtCUrrS. Complete the basic course with ampiitier configurations, biasing, coupling, audio amplifiers, closed-loop vs. open-loop operation and more. EV-3104-A. An activity-filled workbook and explanation of how to solve each problem comes with each tape so you learn three ways — video . workbook and hgndg-Qn l Opdep today! Can Toll free, Z4-4iours a day. 1 -800-253-0570. We accept VISA, MasterCard, American Express and Heath Revolving' Charge card. Use Order Code 601 -01 8. ® Heath Benton Harbor, Ml Calfor a HtScat^ 1 -SOO^WATH. 'PrIoB does not include shipping and liancfling, orapplicabiesalesta^t. m -0 CD ©1990,HealtiC(impany -^ Subsidiary of Bu II Data SystBdiB . I nc. 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WARNING : SCO Electronics and RXII dealers do not encourage people to use the Digital Video Stabilizer to duplicate rental movies or copyrighted video tapes. RXII is in- tended to stabi- lize and restore crystal clear picture quality for private home use only. f Dealers Welcome) ToOrder: $49.95 sa + $4 tor FAST UPS SHIPPING 1-800-445-9285 or 516-694-1240 visa, M/C. OOD M-F: 9-6 (ballery not Included) SOO ELECTRONfCS INC, Oept-CEYS 581 W. Merrick Rd. Valley Stream NY 11680 UnCOnditk?n«l 30 days Money Back Guarftntft« I CIRCLE 190 ON FREE INFORMATION CAHD CABLE TV DESCRAMBLER < IB lUnit 10 + JerroldS.B. $74 $55 Jerrold SB w/Trimode $90 $70 Oak N-12 (w/VS) $89 $65 Scientific Atlanta $109....$75 Pioneer $109....$75 Panasonic converter ...$98 $79 73 channel converter $79 $59 We Beat Anyone's Price! 30 Days Money Back Quaranty F^ee Catalog Visa, M/C. COD or send money order 1o: US Cable TV Inc. Dept. kct9 4100 N.Powerline Rd., Suite F-4 Fompano Beach, Fl 33073 1-800-445-9285 Please have make and model number o1 the equipmeni used in your area ready. No Florida Sales! It's not the intent o1 US Cable TV Inc. to defraud any pay TV operator and we will not assist any company or individual in doing so. CIRCLE 191 ON FREE INFORMATION CARD Equation Library Hewlett-Packard calls the 48SX3r\ expandable calculator. One way it can be expanded is w/ith plug-in cards, such as the HP Solve Equation Li- brary Applications Card, which con- tains nnore than 300 science and engineering equations. The library's main menu contains such entries as ELECTRICITY. FLUIDS, HEAT TnANSFEfl, OPTICS. OSCILLATIONS, and SOLID STATE DEVICES. Each main entry contains sub-entries and equations, and in some cases, pictorial representations. The equation library also contains a library of constants. Avogadro's number. Planck's constant, and the rest mass of an electron are among the 40 physical constants in the li- brary (In both SI and English units). A periodic table is available, as are various financial applications. And of course, things wouldn't be complete without a game of some sort. Minehunt should provide a pleasant diversion for both the bored and the frazzled engineer Although the equation library Is the only currently available ROM card, HP does plan to introduce special cards to customize the HP 48SX for specialized applications. Serial interface kit For those more comfortable work- ing with a large monitor and standard QWERTY keyboard, an RS-232 inter- face allows you to take full control of the calculator from your PC or Macin- tosh. Programs, plots, and data can be stored on dlsks^a convenient way to swap them with other users. The Interface kit gives your PC as much or greater power (although not the speed) of many comparable math software packages. But try putting one of those packages in your pocket and using It without a computer at- tached! Of course, the power of the HP 4SSX doesn't come for fnse. The cal- culator itself costs $350. The serial interface carries a list price of $99.95, as does the HP Solve Equa- tion Library Application card. RAM cards cost $79.95 (32K) or $250 C128K). With the 48SX. Hewlett-Packard maintains its leadership position in the scientific-calculator business. While we're inclined to say that the 4SSX Is the last calculator you'll ever need, we won't — HP is probably al- ready hard at work to make its suc- cessor even more Impressive. R-E CHEMICAL SOLUTIONS FREE CHEMTRONICS CATALOG! Comprehensive new source for over 200 products used in electronic manu- facturing and field service. E-Series products are COj propelled for ozone safety. 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As you build this fully IBM AT-com- patible micro from the keyboard up, performing key tests and demonstrations at each stage of assembly, you actually see for yourself how every section of your computer works. You assemble and test your computer's 101-key "intelligent" keyboard, install the power supply and 1.2 meg SW" floppy disk drive, then interface the high-resolution monitor. But that's not all. You go on to install a powerful 20 megabyte hard disk drive— today's most-wanted computer peripheral— included in your training to dramatically increase the data storage capacity of your ^. computer while giving you lightning-quick data access. By getting inside this powerfiil computer, you get the confidence-building, real-world experience you need to work with, u-oubleshoot, eind service today's most widely used computer systems. "* 4. ^mif' ^B l\1ake sure you've always got someone to turn to for help f^fif*^ w^^i. Throughout your NRI training, you've got the full support of your personal Nf?I instructor and the enhre NRI technical staff. Always ready to answer your questions and help you if you should hit a snag, your instructors will make you feel as if you're in a classroom of one, giving you as much time and personal attention as you need. 5. step into a bright new future in computer service— start by sending for your FREE cataiog today! Discover for yourself how easy NRI makes it to s ceed in computer service. Send today for NRI's I lOftfiage. fiill-coior cateilog describing every aspect of NRI's oneproce»M»rs n Robotics D TV/Video/ Audio Servicing P Telecommunications Name n Security Electronics D Electronic Music Technology G Digital Electronics Servicing n Computer Programming D Basic Electronics I .Address I City I State . _Zip_ Accrediied Member, National Home Study Council m ■o H m en m CO u> o 21 NEW PRODUCTS Use the Free Information Card for more details on tfiese products. tn O z 1 u o o < FIBER-OPTIC DE- SIGNER'S KITS. Pro viding a leam-by-doing ap- proach to the design and use of fiber optics in data communications, Sintec's Fiber-Optic Kits are avail- able in both simplex and duplex versions, for single or bi-directional links. No previous training or experi- ence is needed to com- plete these hands-on courses. Each contains all the components required to construct a 10-meter data link, which can be ex- tended to 60 meters with optional extension pack- ages. The link operates off a single -f-5-volt power supply and interfaces to all TTL/CMOS logic devices. Each kit contains fiber-op- tic emitteKs), detectoKs), printed wiring boardCs), all necessary electronic com- ponents, and 10 meters of CIRCLE 15 ON FREE INFORMATION CARD either simplex or duplex ca- ble. The fiber-optic connec- tions for interfacing to the emitter, the detector, and two bulkheads are also in- cluded, along with a fiber- optic splice. The connec- tions are made from a dry, non-polished interface that is easy to handle and re- quires no special tools. The parts are packaged in an impact-resistant plastic box, which also contains assembly and fiber-termi- nation instructions. Prices for the fiber-op- tics designer's kits range from $59,95 to $89.95, de- pending on the version and the length. — Sintec Company, 28 8th Street, P.O. Box 410, Frenchtown, NJ 08825; Tel. 201- 996-4095; Fax 201-996- 3891. DIGITAL/ANALOG MULTIMETER. Sporting both 3'/4-digit and linear bar-graph readouts for measurement display to 4,000 counts. B&K-Preci- sion's model 2919 hand- held digital/analog multi- meter is designed for situa- tions where the accuracy of a digital readout and the responsiveness of an ana- CIRCLE 16 ON FREE INFORMATION CARD log display are needed. The 41-segment bar graph, which is updated 20 times per second to follow changing values, simplifies peaking or level adjust- ments. "Data hold" imme- diately freezes the dis- played digital reading, and "peak hold" holds the high- est digital value obtained during a measurement, while "min/max" memory stores the lowest and high- est reading observed. The model 2912 also of- fers selectable auto- or manual ranging; measure- ment of voltage, current, and resistance; diode check; and an audible con- tinuity check. Additional functions include capaci- tance measurement up to 40 mP and frequency to 400 kHz. The meter is rated at 0.3% accuracy on DC volts, and spans 40 ranges, including the fre- quency counter and capac- itance functions. It is well- protected against reverse polarity and overioads, and features high-energy fus- ing to protect the jiA/mA current ranges. The 2912 handheld ana- log/digital multimeter costs $149.00.— B&K- Precision, Division of Maxtec International Cor- poration, 6470 West Cor- tland Street, Chicago, IL 60635; Tel. 312-89-9087. COAXIAL ADAPTER KIT. Pomona's Model 5693 Universal Adapter Kit allows lab workers, field- service/installation techni- cians, and designers to quickly "mix and match" al- most any combination of coaxial end termination styles, including banana plugs. The specially as- sembled kit allows users to make their own adapter combinations, such as SMA to BNC, or BNC to double banana plugs for connecting coax to instru- ments. The kit includes two male and two female of each the following: BNC, TNC, SMA, and "N" adapters. Four intermedi- ate coupling nuts, one dou- ble banana plug, and one double banana jack/bind- ing post round out the as- sortment. Each of the double-ba- nana jack/plug adapters are fitted with an integral coupler to accept any threaded coaxial con- nector. Individual con- nectors can be joined with a coupling nut to any other CIRCLE 17 ON FREE INFORMATION CARD to make the required coax- ial assembly The high-qual- ity adapters, which come equipped with gold-plated center pins and silver- plated bodies, are pack- aged in a convenient reusa- ble plastic case. The model 5698 Univer- sal Adapter Kit costs $99 00.— ITT Pomona Electronics, 1500 East Ninth Street, P.O. Box 2767, Pomona, CA 91769; Tel. 714-623-3463, Fax 714-629-3317. 22 CIRCLE 18 ON FREE INFORMATION CARD BATTERY TESTER. A quick, inexpensive means to determine the condition of a wide variety of bat- teries is provided by the BT-20A Battery Tester fronn A.W. Sperry. The compact, handheld instru- ment can be used to test all popular batteries from 1.25- to 22. 5-volts DC— in- cluding hearing-aid bat- teries; "AAA," "AA," "C," and "D" cells; 6-volt lan- terns; 3-volt lithium bat- teries: and 5.6- to 6-volt photo cells. The rugged tester is reliable and easy to use, and comes with a one-year warranty. The model BT-20A bat- teiy tester costs $15. 95. — A.W. Sperry Instru- ments Inc., 245 Marcus Boulevard, Hauppauge, NY 11788; Tel. 516-231-7050. HANDHELD LOGIC ANALYZER. Intended as an affordable alternative to multiple logic probes. Global Specialties' model LM-8 TTL logic analyzer has trigger word recogni- tion that allows to it be used in place of more com- plex logic analyzers for troubleshooting 8-, 16-, and 32-bit microprocessor circuits. The LM-8 has eight input channels, an ex- ternal clock input, and an oscilloscope trigger out- put. The number of chan- nels can be expanded to as many as 32 by linking four pods together and trigger- ing from a 32-bit trigger word. The captured data can be displayed by the built-in LED's or on an os- cilloscope. Each channel's trigger can be set to 0, 1 , or "don't care." The logic sta- tus of each channel is con- tinuously displayed on the LED's. Pulse stretching al- lows high-frequency or short-duration pulses to be viewed. The maximum CIRCLE 19 ON FREE INFORMATION CARD clock frequency is 25 MHz, with pulses as narrow as 10-ns wide being captunsd and displayed. The LM-8 provides two operating modes: run and TRIGGERED. In the RUN mode, the data is continuously up- dated every time the trig- ger word is recognized. In the TRIGGER mode, the data is captured and . displayed until the trigger word is rec- ognized, at which time the analyzer is halted and the last data held. The LM-8 handheld logic analyzer, complete with grabber leads for each data channel, costs $249. 95.— Global Specialties, 70 Fulton Teirace, New Haven, CT 06512; Tel. 1-800- 572-1028. MULTIMETER LEADS. Silicon-rubber multimeter leads from Test Probes, Inc. remain soft and flexible even under conditions of Model UTC^^OM 2QaoH 2210A j:HK)flrA Puit'CUon Freq, Period RnliDilnterval. Av|f, Preaicfll*: Prequfncy FrequFncir' Frvqufil^ Haniro IOHk. £,4GHz lOMHt- 2AG\\x •2 iCih IMHk- Display w 'Tun Clio II 10 DitHl LCD a Dii.Mi LED LED IndkAlor 16 Ri?|fmeTilL Adjufltabl* Bjiffjrtiph IS SffEmtJiil Adjl'iitll'hlt BariET'CLph - - Price *37S. •325. $239. $L7a. Sensitivity: < 3 to -clOmV tyjjicsL Timr lia.si-:* 1 lajim., ^..jppffl BdJ S LED Modiste: +. .^ppin nrfd SBO. - LCI) ModeliT Nacadw & ArchiirpfP ndap[>Gr includetli. Cnrr^ Ciliw, Antt-nrni" nnel f^rubo* ■ txira. One yaar ptvrlA & lobar warr[]lnl^' nn ^| prVi^UCUt. i OPTOELECTRONICS name in HANDI-COUNTERS Check These Incredible Features On The All New UTC3000 < lOHz 1d2.4GHz Rangt. Simply Dninzing] * lODi^U LCD Display. ]Hz roMolutLon to ovtr 150 MHz direct. Readable in bright sunltghL • HF Signal Strength Bar^aph. IS Segment. Zero. & Full Scate adjtiatment, SEE the input signal! • Supersensitivity. pinn, E-lnttdlmt:. iMiisitnufn SIHj l',S. S Canada iS'f ouuid^cu'nUTii'o It! FL add'B^f sntr?. las. Ftjll-lintf Prttditcl and Acctsscry' t'nlnlo^ available on ritiiiP?H, m CD m 3) (O O 23 CIRCLE 1S4 ON FREE INFORMATION CARD CIRCLE 20 ON FREE INFORMATION CARD extreme cold. The TLS200 owes its flexibility to the fine silicon wires in the ca- ble. It fits all makes of ana- log and digital multimeters that are equipped with standard 4-mm input jacks. Offered in straight or right- angle plug versions, with an array of interchangeable accessories available, the leads are suitable for a wide variety of measure- ment applications. Their low contact resistance fa- cilitates accurate measure- ments of low voltages and resistances. The TLS2000 multime- ter leads cost $30.00.— Test Probes, Inc., 91 78 Brown Deer Road, San Di- ego, CA 92121; Tel, 619-535-9292. PREISOLATED POWER TRAN- SISTORS For use in color monitors, power sup- plies, and high-voltage switching applications, Samsung is offering pre- \\\ ij CIRCLE 21 ON FREE INFORMATION CARD LEARN TO BUILD & PROGRAM COMPUTERS WITH THIS KIT! INCLUDES ALL PARTS, ASSEMBLY & LESSON MANUAL MODEL MM'8000 $129.00 o UI _l m 6 Q < DC 24 Starting from scratch you build a complBte computer system. Our Micro-Master * trainer teaches you to write Into RAMs, ROMs and run a 8085 microprocessor, which uses the same machine language as IBM PC, You will write the initial instructions to teli ttiB 8085 pro- cessor to get started and store these instructions In permanent memory In a 2816 E' PROM. Teaches you all about Input and output ports, computer timers. Build your own Keyboard and learn how to scan keyboard and display. No previous computer knowledge re- quired. Simple easy to understand Instruction teaches you to write in machine language, add 5% For ShiDDing. C&S SALES INC. (800) 292-7711 1245 Rosewood, Deerfleld. IL 60015 (312) 541-0710 15 Day Money Back Guarantee Write For Free Catalog CIRCLE 109 ON FREE INFORMATION CARD isolated bipolar powertran- sistors in T0-3PF pack- ages that simplify mount- ing procedures. The iso- lated packages offer better EMI control for ungrounded heat sinks, require less mounting hardware, and are cost effective, The power transistors can han- dle 1500-volt collector- base voltage. The devices have a 5,000-volt isolation rating, eliminate bushings and isolation pads, and have no exposed metal sur- faces other that the leads. The pre-isolated power transistors have excellent thermal characteristics when mounted to a heat sink and an industry-stan- dard footprint. The devices are built with special over- sized lead frames for good heat-spreading perfor- mance. A thin, tightly con- trolled thermal epoxy over a back-mounting surface further improves their heat- spreading capabilities. Bght devices— XSDSOW- KSD501 7~are available. When ordered in quantities between 100 and 999, the prices range from $1.55 to $2.10 each, — Samsung Semiconductor. 3725 North First Street, San Jose, CA 951 34-1 708; Tel. 408-434-5400. DIGITAL CLAMP METER. Four advanced digital clamp meters intro- duced by C.G. Instruments have 3%-digit displays and offer up to 4,000 counts. All four meters are UL listed and have rugged, drop-proof enclosures. They feature large clamp- ing jaw openings to allow easy measurements of ca- bles and bus bars up to 2.95 inches in diameter. The Soar 632 AC Clamp Meter (shown in photo) has a basic accuracy of ± 1%. provides 3200 counts, and has an analog bar-graph indicator. Its fea- tures include auto and man- CIRCLE 22 ON FREE INFORMATION CARD ual range select, data-hold function, audible continuity test, and low power con- sumption. The 632 mea- sures AC current to 1000 amps in two ranges. AC volts to 630 volts in two ranges, AC/DC volts up to 630 volts, and ohms to 3.2 Kohms in two ranges. The Soar 641 and Soar 642 each provide 4000 counts and feature an analog bar- graph indicator, data hold, peak hold, max hold, aver- aging functions, and diode- audible continuity test ca- pabilities. The meters measure AC to 1000 amps in three ranges, AC/DC volts to 630 volts in three ranges, ohms to 4 Kohm in two ranges, frequency from 20 Hz to 999.9 Hz with 0.1 Hz resolution, and tempera- ture from — 50° to -H130°C. The model 641 has an average-type sens- ing mode; the 642 offers true RMS, The fourth in- strument in the group is the Soar643, a true RMS, mul- tifunction, AC/DC current clamp meter with 4000 count that measures AC/ DC current to 1000 amps as well as all the features of the models 641 and 642. List prices for the digital clamp meters start at $124.95.— C.G. Instru- ments Corp., 434 Wind- sor Park Drive, Dayton, OH 45459; Tel. 513-434-6952; Fax 513-434-7643. R-E Electronics KrDDDilD^/^© CALL NOW AND RESERVE YOUR SPACE • 6 X rate $940.00 per each insertion. • Fast reader service cycle. • Short lead time for the placement of atis. • We typeset and layout the ad at no additional charge. Call 516-293-3000 to reserve space. Ask for Arline Fishman. Limited number of pages available. Mail materials to: mini-ADS, RADIO-ELECTRONICS, 500- B Bi-County Blvd., Farmingdale, NY 11735. FAX: 516-293-3115 SIMPLY SNAP THE WAT-50 MINIATURE FM TRANSMITTER on top of a 9v battery and hear every sound in an entire house up to 1 mile away! Adjustable from 70-130 MHZ. Use with any Fl^ radio. Complete kit $29.95 + $1.50 S + H. Free shipping on 2 or more! COD add $4. Call or send VISA, MC, MO. DECO INDUSTRIES, Box 607, Bedford Hills, NY 10507. (914) 232-3878. CIRCLE 1Z7 ON FREE INFORMATION CARD CABLE TV CONVERTERS AND DE- SCRAftflBLERS SB-3 $79.00 TRI-BI $95.00 MLD-$79.00 M35B $69.00 DR2-DIC $149.00. Special combos available. We ship COD. Quantity discounts. Call for pricing on other products. Dealers wanted. FREE CATA- LOG. We stand behind our products where others fail. One year warranty. ACE PROD- UCTS. P.O. Box 582, Saco, ME 04072 1 (800) 234-0726. CIRCLE 75 ON FREE INFORMATION CARD APPLIANCE REPAIR HANDBOOKS— 13 volumes by service experts; easy-to- undersland diagrams, illustrations. For major appliances (air conditioners, refrigerators, wastiers, dryers, microwaves, etc.), elec. housewares, personal-care appliances. Basics of solid state, setting up shop, test instruments, $2.65 to $7.90 each. Free brochure. APPLIANCE SERVICE, P.O. Box 789, Lombard, IL 60146. (312) 932-9560. CIRCLE 64 ON FREE IMFORMATION CARD ONE HOUR PROTOTYPING LOCH NESS INC. 1 HOUR PROTOTYPING!! Develop Multi- layered Printed Circuit Boards in Less than 1 Hour with the New Loch Ness Quick-circuit Kit! Process is Patent Pending. No dangerous UV lights! No hole drilling! No mistakes! Kit comes with everything to make 216 sq. inches of PCB. Money back guarantee. Send $65.00 to LOCH NESS, INC., 3700 Colfax Avenue South, Minneapolis, MN 55409. 1-800-323-8623. CIRCLE 193 ON FREE INFORMATION CARD LOW COST PC LOGIC ANALYZER. De signed for students and hobbyists working with 5V TTI/CMOS signals in the Khz range. 36" data cable — eight channels, external clock, ground. Selectable trigger & clock edge, internal clock (iHz-IOOKhz). Full-fea- tured software, slate table graphics, file/print utilities, etc. Over 100,000 samples/sec on 12 Mhz AT UM— $99.95, PHOTRONICS, INC. 109 Camille St., Amite, LA 70422 (504) 222-4146. CIRCLE 199 ON FREE INFORMATION CARD THE MODEL WTT-20 IS ONLY THE SIZE OF A DIME, yet transmits both sides of a tele- phone conversation to any FM radio with crystal clarity. Telephone line powered - never needs a battery! Up to 'A mile range. Adjusta- ble from 70-130 MHZ. Complete kit $29.95 -I- $1.50 S-t- H. Free Shipping on 2 or more! COD add $4. Call or send VISA, MC. MO DECO INDUSTRIES, Box 607. Bedford Hills. NY 10507. (914) 232-3878. CIRCLE 127 ON FREE INFORMATION CARD GET YOUR RECHARGE CATALOG FREE.. .EARN BIG $$ IN YOUR SPARE TIME — All supplies and Do- 1 1- Yourself kits with complete instructions available. Sup- plies cost from $9.95 in qty and you can sell recharged toner cartridges for $40.00 to $55.00 each. Printers include HP LaserJet and Series II, Apple LaserWriter, QMS, etc. Canon PC-25 Copier also. CHENESKO PRODUCTS, 62 N Coleman Rd., Cen- tereach, NY 11720, 516-736-7977, 800-221-3516, Fax: 516-732-4650 CIRCLE 183 ON FREE INFORMATION CARD CO m m ra m J3 CO to o 25 NEW LIT Use the Free Information Card for fast response. CIRCI-E 23 ON FREE INFORMATION CARD STATICIDE: THE PER- FECT SOLUTION TO COSTLY STATIC PROBLEMS. ACL In corporated, 1960 East Devon Ave.. Elk Grove Village, IL 60007; Tel. 708-981-9212; fax 708-981-9278; free. This 8-page, full-color catalog of static-control products features Staticlde liqutds, wipes, floor finish, electrostatic locators, work-surface cleaners, and surface-resistivity meters. New products include lint-, free wipes, dual-tipped foam swabs, and the Tech Essentials cleaning kit line. CORDLESS TELE- PHONE BATTERIES. Power Pak, Inc., 6216 Oakton Street, Mor- ton Grove, IL 60053; Tel. 1-800-637-2212; free. This guide to replace- ment batteries for cordless telephones is written to help the user make an intel- ligent, well-informed selec- tion. The brochure is filled with specifications and complete cross-reference material, along with other information about replace- ment batteries. CIRCLE 24 ON FREE INFORMATION CARD CIRCLE 25 ON FREE INFORMATION CARD ELECTRONIC SECUR- ITY AND MODERN CONVENIENCES. Vantage Point Tech- nologies, 630 Nordahl Road, Suite P9, San to o z o H a o o < 26 CRAMOUN' DeOxidizer DEOXIDIZES • CLEANS • PRESERVES • LUBRICATES • CRAMOLIN'- teOxidizH . . .is o fasHicttng deoxidiring solution lliot deons, preswues, mid lutffltotes oil tnerol iurfoces inclDrfing goM. When opfllied to mBtol contKts, connectors flnd flthei metol surfutes, CMMOLIN* DeOxidizGC lemoves teastive oxides and fomts a pratective molecular layer ttiot adhetes to ruefal surfaces, preventing future oxi- dotion. CRA/AOIIN® DeOxidizer maintains raaximuni electTical conductivity, reduces wear, ond has excellent migrotion properties, IDIAL fOR: • SwilcliBS £ Selnys • Connecting Cotiles SAdoptoR • Edge Cmirtettois • Iermir«il Sitips • Pluji S Sockers • Gold PtarHJ Connectors • PotenlkjmerH! • Bolter^ Conrocls U$lt> BY most WHO OmAMD Wl BIST; • lell S Howe II • Copirol Records • Dolby toheioiojiM • Hewlert Poctord 'Mn Fluke Mfg. • Mtlnlosb Lobs •MCHScrvy) •ttotorcte •NiS* •Knkomichi • RCi • Switctif rofl COHDUaiVITT LABOHATORIES. INC. RO.BoxJ*fetDrtkk),tA92025«51 (il9)743-7]43»BW:(61flW2460 »■ Dzk4i4 Sil» Pn9|Hll«ntii * bpiriltf in Afly Pairil4n CABLE ■ TV SIGNAL REMOVERS •FOR ELIMlNATrON OF SEVERE INTEnFERENCE •FOR -CENSORrNG' OF ADrjLT BROADCASTS ■ ATTCNUATrON - ie 0. 1 'J rr^ — ^ ig 2MIJ Mii- FieqiKnty 30 ItHi to 200 kHi • CopKidme if I : j^^^s i 1° ^Oc^ * i-OflH LiyH |TTl} * TEanujlor fiain ■ Dipdt junclion ^^M Kit • Drop rtiiirMI cost • nil ilond. Model 3M-HD ^ OUR BEST ;s^ ■^ PRICE EVER ^W8^ FULL 3-YEAR WARRANTY ON ALL B&K SCOPES from JOSEPH EIECTROHICS BONUS VMUE! EXTRA UNIVERSAL SWITCHABIE SCOPE PROBE l|9» $J9 Vo/ue 3-pD5ifiDn — \f., \%\, lOx • Rtsetime 1«ss ihan 1 .5 nitc * Excludes interference even an mofi sensitive ran-gts'lt qed; wi^h^farMSi hent LimhO- tiy • Universal for alf scopes. 70 Mlti dmIu iianihf idih * )0MS/jiarn|}lirtg[(ile-2li mwiMy pw f hurnfl • IftMHz equivaltnE lime lamplin^ ' Pre- Irigger [npiufd'. frwn in[hHl«[l- ^ Model 2522 wmB. Q-30V DC O-SA SCOPE POWat SUPPLY I mV/di(' ««ilhfi[y • SpKpi H» 2ras/diy • 13 tin!ibrriil«{ racioH; JO on ifcby«d Nn« b(p.e • (ofi[i(n1«f delay liine mullialur * Signai delnji lire ' \W HceWiol^rKi vollcw • ^ nwdt Irngering • Uiannf I f iKiflpifLPfMeiirKliKled. Model 2390 $J32S^ lav rijiple * Kiqu\a\tA tamtatfl Tolt or iurienl o^»1pu^i • ? turren^ rongci * l»ilaEtd auhfiur — Bmi grc-ufld eliKd polniity ■ Qve^llHa, reverse (nlarity prolHiitfi ■ Porottil, HfiK [apflbithy. I'VeaFwarranEy. »„ Mfldfl 1630 0-J6VK 0-lOA k'iiij;M:'.Mim CanlinuQLt^ly VBrnble volloge t {urienf • Cerrilanl'VftlfmE I {or- ilanl-ciJirtn1 wioAk ' Vuiogc I {uriEdi QHolo^ m\t\i * Ih nnd IDA {urrerl lenge ImilL 1 '^ecr^ O-ISOVAC 9W" mm CALL TOLL-FREE . SAME-DAY SHIPPING CIRCLE 192 ON FREE INFORMATION CARD Kea. Mi 57. SO iliftim ml H«lliH l< ll.lteiBiiiliDilil7 00k3 sra hardcover unless numtier is folk>(vad by a "P" lor paperback. [PutJiish&rs' PfiMS Shown) ©18B0 ELECTRONICS BOOK CLUB, Blue Ridge Summit. PA 17294.0810 Call Toll-Free 1-800-233-1128 to join Now! ELECTRai>iicsBaahC;.LiB' Blue Ridge Summit, PA 17294-0810 I ] YES! Please accept my membership in the Electronics Book Club and send the 5 volumes listed tielow. plus my FREE copy ol Dellon T. Horn's All-Time Favorite Eleotronlc PfOjecls (310SP), billing me $4.95. II not satisfied. I may return the books within len days without obligation and have my memtieiship cancelled. I agree to purchase at least 3 books at regular Club prices during the next 12 mpnlhs and may resign any time thereafter. A shipping/handling charge and sales tax will be added to all orders. Name Address City State Zip Phone Signature Vali{l Tor flew (nembsrs only. Foreign applicants will receive special OTdering instructions. Canaoa must remil in U.S. i:uTr^ncy. Tliis at^er subjKC ta accept^ce by Ihfl Electronics Baak Club. RE^D m CD m 33 (O O n Radio Shack Parts Place YOUR SOURCE FOR PROJECT AND REPAIR ELECTRONICS Try our Special-Order ''Hotline" ICs, Crystals, Tubes, Much More Your Radio Shack store manager can special-order a wide variety of pans and ac- cessories froTii ojr main warehouse. Over 200,000 items are avaiiabie including va- cuum tubes, iCs, microprocessors, phono cartridges and slyli, crystals for scanners and computers, even SAMS Photofacts^ manuals. Best ot ali, there are no handling charges or minimum order requirements. Your order is sent directly to the Radio Shack near you and we nolify you when it arrives. Delivery time for most items is about a week. infrared Module Neater wiring Battery Special-Order Service Hundreds of Types Available In addition to our large in-store stock. Radio Shack can now supply almost any currently manufactured consumer-type battery— for cordless phones, computer memory, camcorders, walkie-talkies, pagers and mora. Batteries are sent from our main warehouse to the Radio Shack near you. We notify you when they arrive and there's no postage or handling charge. Tantalum caps "Snap" RR Choice Complete, Easy - to • Use IR Detector Heart of a remote-control project! Combines detector, limiter, band- bass, demod. integrator and com- parator in a compact 3-lead module. •f27B-137 3.49 (2) (3) (1) Heat-Shrink Tubing. Vi6 to 'k" siiBS. *278-1627 Pkg. of 7/1.79 {2) Cable Tie/Markers. Fof cables up to sft" dia. #278-1648 . Pkg. o! 10/2.49 (3) Wire Markers. 630 "peel and slick" gharaciers *S79.i650 Set/1.79 High capacitance in a tiny size. mF WVDC Cat. No. Each 0.1 35 272-1432 .59 0.47 36 272-1433 .59 1.0 35 272-1434 .59 2.2 36 272-1435 .69 10 16 272-1436 .79 22 16 272-1437 1.19 1^ Snap-Togetiier Toroid Cores. Effectivet "madbEock" la radio -frequency inteHer- ence. Just wind on AC, phone, compuler. coax OT audio cabte. ll^e^ snap choice together. '*273'V04 . . Stl of 2/7.9S Resistance Items Shielded D-Sub Hoods "Ding- Dong" chime Rod Antennas (1) 15-Tum Tfimmars. Ik, if271-342 tOk, »271-343 20k, #271-340. Eacli 1.49 (2) Precision Thermistor. Resistance changes In proportion to ternperatore -50 to -I-110' C. *271-110 .... 1.99 (3) Color-Code Decoder. t271-12t0 79« (n m H Fig. Description Cat. No. Each 1 2 9- Position Melal 25-Posilion Melal 9-Pos. Metalijed 25-Pos. Metal iieO 276-1508 276-1510 27S-1513 276-1536 2.19 2.79 1.49 1.99 i TNC and Mini-UHF connectors (1) ^ n (2) 0) fH (4) (1) TMC Twisl-On Male for RC-S8 Ca- ble. (^278-140 1-99 I r (6) (7), |2) TNC Double-Female. C 278-1 4: ,1.99 Fig. Accepts Fiis TNC Cat. No Each 3 4 PL- 259 BNC Male Female Female 278-118 278-115 3 49 4.99 (5) MInUUHF Double- Femite. Joins two male mini-UHFs. #278-172 2.49 (6) Mlnl-UHF T Adapter. Female-male- female power divider #278-173 . 3.99 (7) UHF Adapter. Accepts PL-259 Fiis lemale Mini-UHF *27&A7A 3.99 Great Entry Alerter A This IC and mini-speaker combo has a pleasant chime output and it's ideal lora customer-enlry alert, doorbell or event indicator. Oper- ates from 6 to 18 VDC. ProduCesSO dB sound pressure at 12 VDC. 5" leads. #273-071 8.99 For projects or replacing damaged an- tennas on cordless liandsetS and bases, walkie-talkies and radios, We have over a d>ozen slyles in stock. For example: Sacticns Extended Cal No. Each 5 6 4 13" IT^i" 343(.- 270-1407 270-1409 270-1402 2.79 2 59 379 solderiess IDC-Tvpe connectors (f) (2) (3) (4) 15) Ra. Description Cat No Each 1 2 3 4 s 25- Position D-Sub Male 25-Posilion D-Sub Female 34-Posi!ion Header 36-Postiion Male Printer Connector 34-P05itlon CarO-Edge Conneclor 276-1559 276-1665 276-152S 276-1533 276-1564 3.99 3.99 2.49 4.99 199 Electronic counter ivioduie Prewired! Great lor a traflic or event counter, CoLnts up to 99,999. Advanced (or reset) by external switch closure or digital circuit. Ac- cepts count rate up to 7 Hz. Has 'fe" liquid crystal display. Requires "AA" battery With data. #277-302 1G.95 Foldup Autoranging DVM Select the tunction and Ibis precision Micronta* meter sets ttie range. Has autonnatic power-off when shut, detented hinge for best viewing angle. Mea- sures to 1000 VDC, 500 VAC, 10A AC/DC, 2 meg- obms resistance. Re- quires 2 "AA" batteries. *Z2-193 69,95 Dual -Power soldering iron Go from 15 to 30 watts with the flick of a switch. Has replaceable tip. SVj" long. UL listed AC. #64-2055 9.49 Replacement Tip, #64-2055 1.19 Chisel Tip. *64-2056 1.19 Since 1921 Radio Shack has been the place to obtain up-to-date electronic parts as well as quality tools, test equipment and accessories. Today, with our big in-store selection and convenient special-order service, Radio Shack continues Its tradition ot suppling high-tech products at com- petitive prices. We're America's Technology Store with over 7000 locations — NOBODY COMPARES Prices apply at participating Radio Stiack stores and dealers. Radio Shack is a dIvisiDn of Tandy Cotpotatlon mRadie/haek AMERICA'S TECHNOLOGY CIRCLE 78 ON FREE INFORMATION CARD 32 BUILD R-E's VOCAL STRIPPER ALMOST EVERYONE ENJOYS LISTENING TO music, and just about as many- people enjoy singing along to their favorite songs. If you're one of the many people who loves to sing, you may be interested in a clever audio device that filters out lead vocals from a stereo record- ing, leaving just the background music. For under $50.00, you can build this unique audio filter- ing device. Impress your friends with this Karaoke-like audio sys- tem and enjoy hours of singing pleasure. Filtering out the vocal tracks from a recording is not as simple as merely eliminating the mid- range frequencies. Along with the vocals, the midrange fre- quencies contain a large portion of the music. Vocal filtering is quite easy, however if you take advantage of the way stereo re- cordings are mixed. Stereo mixing Wlien mixing is done in a stu- dio, each instrument or voice is assigned a position relative to left (L) and right (R) channels. Some instruments are recorded at higher levels on the right channel so that their sounds seem to come from the right side of the stage. Others are recorded on the left channel for the opposite effect. Lead vocals and instru- Bulld this lead vocal filter and test your singing ability. TERRY J. WEEDER ments such as the bass drum and bass guitar are usually re- corded at the same level on both channels so they seem to come from center stage. That is what makes lead vocal filtering possi- ble. Vocal signals, which consist primarily of mid-high range fre- quencies, can be filtered out by a series of filtering stages shown in Fig. 1. Bass instruments, corre- sponding to a lower frequency range, can be diverted to a final mixing stage so that the music is not filtered out Eilong with the vo- cals. A signal from one channel is inverted and subtracted from the B1SHT CHANNEL IN CcS — BUFFER {BASS INSTRUMENTS) LOW CROSSOVER iHWm (VOCAL ' SIGNALS) VARIABLE DELAY S LEFT CHANNEL IN r R49 PHASE R36 BALANCE BUFFER CROSSOVER Vi'J^ Ih I/MID I ?4ms I i, PtvOCAl' l DELAY | (VOCAL ' SIGNALS) LOW PASS FILTER ll DIFFERENCE AMP :^ LOW PASS FILTER -T""^ MIXERt VOCAL-LESS f SIGNALS LOW (BASS INSTRUMENTS) V BUFFER RIGHT CHANNEL OUT LEFT CHANNEL OUT BUFFER FIG 1— BLOCK DIAGRAM OF FILTER NETWORK. Right channel signal is inverted and subtracted from the left channel, cancelling the lead vocals. Low frequencies are by- passed by an active crossover and remixed with the difference signal, without the vocals. 33 > g o m o 3D O Z o 33 other (L-R), which causes the lead vocals that are common to both channels to cancel out. The music common to the left and right channel remains un- changed. Unfortunately, along with the lead vocals, all low fre- quencies are common to both channels and must bypass the cancellation circuit. A simple ac- tive crossover removes the low frequencies so that they can be remixed with the vocal-less sig- nal at a later stage. From the active crossover stage, all midrange and high fre- quencies pass through a variable delay stage, U'hich is used to al- ign the left and right channel sig- nals so that they are exactly 180° out of phase with each other. Proper signal cancellation is achieved only when both signals are 180° out of phase. The low- pass filter stage filters out un- wanted high frequencies from the variable delay stage. The out- put of the low-pass filter enters a difference amp. where the lead vocal signals cancel, and is then remixed with the low frequencies at the final mixing stage. Here's how it works The schematic of the lead vocal filter is shown in Fig. 2, The left and right channel signals are coupled through CI and C2 to buffer amps lC4-a and IC4-b. From the buffer amps, the left and right channel signals pass through active crossovers lC5-a and lC5-b, sending all low fre- quencies to a final mixer lC6-c, and all middle and high frequen- cies to analog delay lines ICl and 1C2, RD5106 256-sample bucket- brigades. Integrated circuit IC2 delays the left channel signal by R4 10K i R3 10K ■*^*TN RIGHT J1 CHANMEK IN C3 R6i 0-474,7Kf - IC5-b 111 1/4 LM3Z4 12V LEFT J2 CHANNEL IN R13 , 47K r^ R14^ V.LM3Z4 ^■^1 R1S. - 10K' rv^c-i-b • wv * IC5-C Va LM324 R16 JOK Ui im2i R17 10K p R18 3,3K 13f^ V* LM324 + 12V i IK< RZO 100K . J3 RIGHT — JP^CHANNEL 021 JL OUT XO.1 2 IC3-a 1/4 4011 B IC3-b \7 V4 4(rl1B ■w- n49 10K PHASE C23 lOOpF 11 towo- IC3-C V* 4011B IC3-d V<4011B :R47 15K * If- C24 100pF m UJ H o. hi CO FIG. 2— SCHEMATIC OF LEAD VOCAL FILTER. Right and left channel signals pass through IC4-a and -b buffer amps into active crossover 1C5; low frequencies are sent to IC6-C iriixer, middle and high frequencies are sent to analog delay lines of ICl and IC2. That output passes through IC6-a and -d to filter high frequency sample steps. ICe-b signals are remixed with low frequencies by IC6-c and are sent to final output via IC4-c and -d buffers. 34 2.4 ms, set by the fixed-frequency clock generated by '/2-IC3, R47, and C24. The right channel sig- nal is delayed by ICl with a varia- ble-frequency clock generated by W-ICa, R48. R49, and C23. Po- tentiometer R49 is used for phase adjustment. The output of each delay line All resistors are vi-watt, 5%, unless otherwise indicated. R1, R2, R20. R24, R32, R33-R35— 100,000 Olims R3, R4, R7-R9, R11. R12, R15, R16, R17, R27, R28. R37, R38, R43, R48— tO.OOO Olims R5, R13, R29, R30, R39, R40— 47,000 ohms R6, R14, R31. R41— 4700 ohms RIO, R18. R44— 3300 ohms R19, R23— 33,000 ohms R21, R25— 1 megohm R22, R26— 10 ohms R36, B49 — 10,000 ohms, potentiometer R42, R45, R46— 22,000 ohms R47— 15.000 ohms Capacitors C1, C2. C7, C12— 1 U.F tantalum C3,C5— 0.47 |j.F tantalum C4, C6— 0,0047 JJ.F Mylar C8. C9, C10, Ct3, C14, Cl5. C25— 0.1 jiF Mylar C11, C16— 2.2 (jlF tantalum C17, C19— 220 pF ceramic disc CIS, C20-^7 pF ceramic disc C21, C22— 10 nF electrolytic C23. C24— 100 pF ceramic disc Semiconductors ICl, IC2— RD5106 256-sample bucket- brigade analog delay line, EG & G-Re- ticon IC3 — 4011 quad two-input nand gate IC4-IC6— LM324 quad op-amp Miscellaneous: Perforated circuit board, standoffs, mounting hardware, hookup wire, shielded cable, 18-AWG power supply cord, strain relief, and four RCA jacks for J1-J4. Power supply parts F1 — 0.5 amp fuse and fuseholder T1-— 24 VAC center-tapped transformer BR1— 1.5-amp bridge rectifier, 100 PIV CI, C2— 1000 M.F, 25 volts, eiectrolytic C3, C4— 10 (iF 16 volts, electrolytic C5, C6 — 0.1 (J.F, ceramic disc D1. D2— 12-volt Zener diode R1 , R2— 220 ohms R3— 1000 ohms SI— SPST switch, 1 amp LED1— light emitting diode, any cotor Note: The following are avaifable from Weeder Technologies, 14773 Lindsey Rd., NH. Orab, Ohio 45154: An etched, drilled, and plated PC tioard, $15.00; a basic parts kit in- cluding all resistors, capacitors and semiconductors (not including power-supply components), $29.00. Please include S2.00 for shipping and handling in the U.S., $3.00 in Canada. Ohio residents add 5.5% sales tax. Allow 4 to 6 weeks for de- livery. from ICl and IC2 passes through low- pass-filters IC6-a and -d, and their associated parts, to filter out high-frequency sample-steps produced by ICl and IC2. Bal- ance control R36 is adjusted for equal amplitude of the left and right channels. IC6-b is a dif- ference amplifier which cancels all lead vocals that are common to both channels. The resulting sig- nal from lC6-b is remixed with low frequencies by IC6-c and is then sent to the output via buff- ers 1C4-C and lC4-d. Construction The easiest way to go about constructing the vocal filter cir- cuit is to use a PC board. An etched and drilled PC board is available from the source in the Parts List or you can make your own from the foil pattern pro- vided here. Mount the vocal filter components as shown in the parts placement diagram, Fig. 3. Use shielded wire to connect the RCA jacks, and ground them properly, either by mounting them to a grounded chassis or by soldering ground wires to their cases. The DC power supply leads from the power-supply board should be twisted to reduce noise transmission. If you don't use PC mounted potentiometers for R49 and R36, be sure to keep their connecting leads short and twist them to re- J3 J£ J1 FIG. 3— PARTS PLACEMENT DIAGRAM. Remember to connect the jumper lead, use shielded cables for the RCA jacks and twist the supply leads before soldering to the LED and main PC board. FIG. 4— POWER SUPPLY SCHEMATIC for the lead vocal filter circuit. 33 > a 5 o z o 35 JUMPER LEAD v^ RCA JACKS SHIELDED SIGNAL LEADS MAIN } PC BOARD^ ••:"| I POWER SUPPLY ■■■:■/ BOARD ~"""C TWIST POWER SUPPLY R49 R36 LBy)g PHASE ADJUSTMENT BALANCE CONTROL FIG. 5— AN INTERNAL VIEW OF THE LEAD VOCAL FILTER. ifi O z o EC h- o LU _l LXJ < duce noise and hum pickup. It is preferable, though, to use shielded leads for these connec- tions. These potentiometers should be grounded by mounting to a grounded chassis. A simple power supply, like the one shown in Fig. 4. may be used for this device. The power supply can be mounted on a perforated circuit board, as long as you closely follow the component con- nections shown on the sche- matic. Although optimum perfor- mance is obtained with a ±12 volt supply, the vocal filter gives good results using two 9-voIt bat- teries connected in series. The power supply and main PC board should be adequately en- closed before operating the vocal filter A metal enclosure is recom- mended, as a 120- volt line poten- tial is exposed in the power supply circuit (see Fig. 5). Hook up and operation The vocal filter should be con- nected into the tape loop of your stereo system. Use shielded ca- bles with phono connectors to connect inputs Jl and J2 to the "record" tape monitor jacks on your stereo, and outputs J3 and J4 to the "play" side. To use the vocal filter with a tape deck that normally uses tape monitor jacks, plug the output "play" jacks of the tape deck into Jl and J2 of the vocal filter. Plug J3 and J4 into the input or "play" jacks of the stereo. Make sure you apply power to the vocal filter before turning on the stereo; sensitive components in the vocal filter may be damaged if a signal is ap- plied before power is turned on. Set R36 to its middle position, play a stereo sound track or tune in an FM stereo broadcast, and switch in the tape monitor Ad- just R49 for minimum lead vo- cals, then adjust R36. Repeat that process Lmtil the lead vocals are suppressed. If you think the vocal filter is not working, tune in to a mono FM broadcast. If you can't find one, tune to a stereo station, and adjust the tuning knob either way, just enough so the stereo light goes off If the vocal filter operates properly, you should be able to adjust R36 and R49 to filter out all music except low fre- quencies. With a little help from Radio Electronics, you now have the know-how to build a fairly simple audio filtering device in just a few short evenings. Once completed, you can use this system to prac- tice singing alone, or be creative and have all your friends over for a Karaoke party! R-E 36 Build R-E's WITH THE EVER INCREASING VARIETY of pay telephone services such as Dial-A-Sex, Dial-A-Party. and Dial-A-Friend, the telephone abuses at home and in the office are reaching alarming propor- tions. For many years, only large corporations were able to afford PBX (private branch extension) systems with facilities to restrict the use of certain numbers. How- ever, now you can build an inex- pensive, microprocessor-con- trolled, integrated telephone line controller that can selectively re- strict outgoing calls, selectively restrict incoming calls, selec- tively dial an array of numbers for promotions, and record all ac- tivities on the telephone line, in- cluding the time, date, and duration of each call. The controller uses an IBM PC or clone as a host. However, the card is almost a stand-alone de- vice. It includes its own micro- processor and runs its own operating program. The comput- er is needed to load the operating program into the controller's static RAM, to initialize opera- tions, and to let the user interact with the controller. The host computer may access the SRAM for reloading firmware, sending and retrieving data, and alternat- ing modes and functions. An in- ternal power supply allows the line controller to operate even when the host computer is turned off The line controller does not have to be installed on the phone line at the point of entry to re- strict outgoing calls and screen unwanted incoming calls. The card can be plugged into a modu- lar telephone out- let at any point along the indoor phone line, without any modification of the existing installation '" — How it works The controller is fully program- mable and can perform a wide variety of functions. Using the software provided on the RE BBS, the controller can prevent a number from being dialed if the prefix matches a number on your "list to restrict" (see Fig. 2). If. for example, the list contains the number 9311, then dialing 931-1882 (or 931-lxxx) wiU be prevented. A list containing 0-9 will prevent all outside calls, and a list containing 0, 1, 20, 21, 30, 31, 40. 41. ..90, 91 will prevent the use of all area codes, operator, and international. The list can consist of up to 128 prefixes, up to 6 digits each. The user may choose to have the controller automatically list all outgoing calls made on the computer screen. The list will consist of the destination tele- phone number, date, time, and duration of each call. The user can screen incoming calls and limit them to as many as 32 relatives and friends. En that case, the card would have to be used in conjunction with a telephone answering machine. The answering machine would prompt the caller to enter his own number. Then, only the numbers that match one on the list will be allowed to go through. Any TELEPHONE-LINE CONTROLLER Take full control of incoming and outgoing teiepiione calls. MORDECHAI SAAD matching number, along with time and date, will be stored in memory for later use. The user can then make a list of the incoming calls appear on the screen. The card can be used to auto- matically dial a number from the keyboard, a number selected from a menu, or a pre-selected range of numbers. The redial function is not limited to the last dialed nuinber, as the user may select a number from a list of pre- viously dialed numbers. Circuitry The line controller contains a microprocessor, memory to hold the software and data, interface circuitry for the host computer, a telephone line interface, and a wall transformer to maintain power when the host computer is off. A schematic of the circuit is shown in Fig. 3. In the center of the diagram is the micro- processor (IC6. a 65SC02). which is an 8-bit CMOS version of the 6502 used in Apple, Atari. Commodor, and other comput- ers. The static memory 1C4, is an 8K X 8 SRAM. The host computer is used to write the program to IC4. The bi-directional tri-state buffer (IC5 ] is enabled by the pro- en m ■D H m fti tD T., 334.99 Club Pr.. SES.SO ON-LINE ELECTRICAL TROUBLE- SHOOTING, fly L Lundnuisi aai'toe pub. h.. mm ant Pi.. sse.ss ESSENTIAL CIRCUITS REFERENCE GUIDE. By i Markus & C. Wesion tlHIia Pub. Pr., S59.95 Cluh Pr.. H7.S0 INTRODUCING PC-DOS AND MS-DOS, second Ed. By T. Sheldon. M5.'651 Pub. Pr, SS9 95 Club Pf.. $19. 9S ENGINEERING FUNDAMENTALS FOR THE PROFESSIONAL ENGINEERS' EXAM, Third Ed. By L.M. Polentz. imam Pub. Pr, KSM Club Pr.. ;27.95 INTRODUCTION TO DIGITAL SIGNAL PRO- CESSING, fly J. G. ProaklsamfO. G. Manolakis. 5M9M-2 Pob, Pr , SSO.DO Club Pr., K7.5B AUTOMATIC CONTROL SYSTEMS. Fiflti Ed. By B.C. Kuo. inm-i Pub. Pr. SS7.4II Club Pr., $43. SO MICROCOMPUTER TROUBLESHOOTING AND REPAIR, fly J.S Steptensori and 8. Cahili UMi-T Putl.Pl.,SE4.9e ClubPl., $16.95 DIGITAL AND MICROPROCESSOR TECH- NOLOGY. Second Ed. By P. J. OConnoi 5SS1M-9 Pub. ?!.. m.m Club Pi.. SU.M MICROELEaRONICS, Second Ed By J. Mill- man inij A Gfabel 423j'3aX Pub. Pi., iX.n CluB Pr.. $41.50 FOR FASTER SERVICE IN ENROLLING CALL TOLL-FREE 1-800-2-MCGRAW -.i___.MAIL THIS COUPON TODAY — ^^_ I McGraw-HUl Book Clubs Electr antes and Control Engineers' Book Ciub<» P.O. Bos 582, Hightstown, NJ 08S20-99S9 please eni'oll me as a member and send me the two books indicated, plus Lhe PORTABLE ELECTROMICS QA'LA fJOOK. I am lo receive one hodk forjusl S2.sy. Ihe oLher at Lhe discounted member's price, plus local tax, shipping and handling chai:ges. j a^me tn purchase a minimum of une additional book during my first year of membership as outlined under the Club plan de- .scribed in this ad. I undei'stand that a shipping and handling chai:ge is added Ici all shipments. Vour FRKK Data Book 5853fl()-K Write Code ^ S2.S9 selecti o. of the on here Write Cod Pirst sell e No. for the jctlon here Signature . Name . Address/Apt. #_ City State . . Zip . This order subject to acceptance by MoGraw-Hill. All prices subfect to change williout notice. Offer good -only to new members. Foreign member acceptance subject to special conditions. ECGA-mi V) m H m m 3) CO O 41 Tar m o z o H o m O Q < DC BATTERY BACKUP (OPTIOMW.) 115 VAC OUTLET TLC SOFTWARE MODULAR TELEPHONE OUTLET FIG. 1— THE ADD-ON-CARD can be plugged into a modular telephone outlet at any point along the indoor phone line, without any modification to the existing installation. 1/ 25 Becords Tel. Ho. lescription 1 6 OperatoT' 2 1 Long Disiance 3 21 Long Bistsfice 1 4 21 lofig BistancG 5 38 Long Distance ; 6 31 Long Distance 1 7 48 Long Distance ! 8 41 Long Distance 'j^^l 9 58 Long Distance H 10 51 Long Distmce il 548 General [nrornation '^^H 12 1 m Group Talk Line ■i ■ h'lii.S.4 ' 1 llW i H i^^H ■ lone PgUp r I PgDn End Ins Del Esc F9=Hore rii*ip FIG. 2— THE CONTROLLER CAN PREVENT a numtjer from being dialed if the prefix matches a number on your "list to restrict." cessor on pin 1 (the direction pin) according to whether the host computer wants to read i'rom or write to the SRAM. Components C16. Rl, and D3 provide the pro- cessor with a power-on reset. The peripheral interface adapt- er (PIA) IC3 is responsible for syn- chronizing the control of the buses between the host pro- cessor (80xx) and the controller's 6502. The DTMF (dual-tone multi-frequency) transceiver. IC7. is constantly monitoring the telephone line for DTMF ac- tivities, as well as for incoming calls. When dialing, the trans- ceiver generates DTMF signals. Resistors R17 and R18 set the gain of 1C7 to 1, C24 provides AC coupling for the Incoming sig- nals, and DIO and Dll are 4.3 volt-Zener diodes; when con- nected back to back they limit the voltage swing on the secondary of Tl to 5 volts (4.3-f-0.7), thereby protecting IC7 and ICll from voltage transients. The transmit- ter output of the DTMF trans- ceiver is buffered by ICll-b to drive the 600-ohm line trans- former Tl. ICll-b is configured as an inverting amplifier with a gain of 1. By connecting the non-in- verting input to a reference volt- age of 2.5 volts, the output swing can extend to both rails, centered around 2.5 volts. The other side of Tl's second- ary is connected to the output of ICll-a which is configured as a voltage follower to buffer the volt- age reference of IC7, and is also used as a return for the line transformer Tl. The on-chip clock oscillator of 1C7 uses a 3. 58- MHz crystal, and the output is coupled to the input of 4-bit binary counter lC8-a via C21. The first-stage output of the counter is the source of the 1.79- MHz clock for the processor. The fourth bit of ICB-a outputs 224 kHz, which IC8-b divides down to 14 kHz. The 14-state counter, IC9. divides the 14 kHz by 1024 down to 13.65 Hz, which is the real-time clock. The 13.65-Hz clock signal is used to tag events such as outgoing calls, incoming calls, and duration of calls, with a relative time and date. The host computer converts it to absolute time and date. Varistors R27-R29 are used as surge suppressors, preventing the tip and ring terminals from exceeding a differential potential of 150 volts with respect to chas- sis ground and to each other. Bridge-rectifier BR2 is used to correctly polarize the telephone line on its way to the line-status and -control circuitry. The ring- detector circuitry is connected directly to tip and ring. It detects an AC signal greater than 100 volts p-p. Capacitor CI 8 blocks the 48-volts DC from opto-cou- pler IClS's LED, and Rll limits the LED's current. When a ring signal is present, the opto-coupler's output tran- sistor is on, which causes 026 to 42 YOU CAN MAKE YOUR OWN PC BOARD for the telephone line controller. This pattern is for the component side o1 the board. discharge, pulling the in- put of IClO-d to ground. The processor reads the output of [ClO-d (high when ringing) into data line DO by enabling ICl. Resistor RIO charges C26 at a rate where the brief pauses between rings will not reach the threshold of IClO-d, thereby main- taining IClO-d's output high. Schmitt trigger IClO-e and IC14 allow the con- troller to "pick-up, " or get on line. The processor sets the input of IClO-e. The output of IClO-e then drives the LED part of opto-coupler IC14 to ground via R7. The tran- sistor part of IC14 then turns on, driving Q3. At this point, the following components are con- ducting the loop current in a clockwise order: R13, 'A of BR2, Q3, LEDl, R9, '/4 of BR2, andR12. LEDl is there only to indicate that the controller has "picked-up." A circuit made up of transistors Ql and 92, IC13, and IClO-c con- tinually monitors the telephone line. When any telephone on the line is picked up, the voltage be- tween the tip and ring drops from 48- to 7-voIts DC and, as a result. Q2 turns off. Transistor Ql then turns on, turning on the transistor in the opto-coupler IC13, caus- ing the output of IClO-c to go high. That tells the processor that somebody is on the line. The pro- cessor reads that signal on data line Dl via ICL IClO-a and -b provide the internal microprocessor with a reset pulse on power up, and on bus- transfer command. The card can get its power from the host com- puter via D2, at least while the host computer is in operation, and the external wall transformer is not connected. The ex- istence of external power 43 g RADIO-ELECTRONICS 3 Q I 5 O O ■n H X m m o O 3 g: o X o w 3 o 8 ■o 3 S 0) CD o m s 3 01 IC14 LED1 -R?-? (i'-w G15 ■ !1 - D3 -R1- O iiiir'ii^! G13 ^R26^ .:f^~^i^ -RZS- BR2 I D13l IC12 : C12 TIT i 6R1 ; n C25^ C11 ||- ) IC11 -R23-' ^f^^T- °^W - ' »R20-- ^R19- C20 Jl., l_frR16- ^ -R18- C7 b IC7 TTT r ) IC9 d8 5 IC8 FIG. 4— PARTS-PLACEMENT DIAGRAM. The card is assembled on a double-sided PC board that fits in an expansion slot on your motherboard. All resistors are Va-watt, 2%, un- less otherwise indicated. R1, R2, RIO, R17, R18— 100,000 ohms R3 — 51,000 ohms R4-R6— 1 megohm R7— 5100 Ohms R8— 4700 Ohms R9 — 300 ohms, Vi-watt R1 1—2200 ohms R12, R13— 5100 Ohms R14 — 3000 Ohms R15, R24-^6,000 ohms R16, R20— 10,000 Ohms R19 — 2 megohms R21, R22, R25, R26— 33.000 ohms R23— 390 Ohms R27-R29— P7056 125-volt surge suppressor Capacitors C1-C11, CI 3, CI 4, C25— 0.22 p.F, 50 volts, ceramic 012 — 470 jjtR 25 volts, electrolytic C1&— 220 (xR 10 volts, electrolytic C16— 1000 pF, 100 volts, ceramic CI 7 — 0.47 fjLp, 50 volts, ceramic C18— 0.22 H-F, 250 volts C19— 1 jjlR 250 volts C20, C21— 0.01 |jlR 100 volts, ceramic C22, C23— 0.1 jxR 50 volts, ceramic C24— 0.015 jjiR 100 volts, ceramic 026— 4.7 ti.R 25 voits, electrolytic PARTS LIST Semiconductors 101— 74HC244 octal tri-state buffer 102— 74HC541 octal tri-state buffer t03— S26041 interface adapter 104— V62C64 8Kx 8 SRAIVf 1C5— 74HC245 octal transceiver 106— 65SC02 8-bit microprocessor 107— SI 8062 DTIvlF processor 108— 74HC393 dual 4-stage counter IC9— 74HC40K) 14-state counter IC10— 74HC14 hex Schmitt trigger 1011- LlylC660 quad op-amp 1012— LK/!2940OT-5 -h5-volt regulator iC13, IC15— 4N32 optoisolator iC14— H11D-2 optoisolator BR1, BR2— DB103 bridge rectifier D2, D3, D5, D13— 1N4148 switching diode D'J— 1N5253B 25-volt Zener diode D1, D6-D9, D12— not used D10, D11— 1N4731A 4.3-volt Zener diode LED1— P300 light-emitting diode (any color) Q1, Q2— IRFD210 N-channel hex DIP Q3— MPSA43 H.V. NPN transistor Other components J1 — H9032 modular connector J2— 8926 747844-1 female D-sub- miniature connector T1— 42HL016 600/600-ohm transfomier XTAL1— 3.679545-MH2 crystal Miscellaneous: PC board, 9-volt 200-mA AC wall adapter, E09P male D-subminiature connector, battery holder, PC bracket, hard- ware, solder, etc. Note: The following items are available from AC&C, 717 E. Jericho Tpk., Suite 101, Hunt- ington Station, N.Y. 11746: A PC board (TLC-1) and OGC Re- strainer software (on S'A-inch floppy disk), $55.00; A wall transformer, modular phone cord, three connectors, and a metal PC mounting bracket $36.00; all the above mentioned items, and all components in- cluding semiconductors, re- sistors, capacitors, and op- toelectronics devices; $198.00. Be sure to add $5.50 to any order for shipping and handling. For technical information, write to AC&C, and please include a self- addressed stamped envelope. AC&C is constantly adding soft- ware functions for the entire product line, and for those with unique applications, AC&C is ready to work on your custom software requirements. m TJ H m m m 3) _L ta CO o 45 CO o z o I- o ir THIS IS THE FOIL PATTERN for the solder side of the telephone line controller PC board. (AC line transformer, and or battery backup) is de- tected by ICIl-d, in order to alert the user before shutting off power on the host computer Resistors R24 and R22 are set to provide the non-invert- ing input of ICll-dwith 2.39 volts. When external power exists, the cathode of D2 is at 5 volts. When exter- nal power does not exist, the voltage drops to 4.3 volts: resistors R25 and R26 divide the voltage by 2, to 2.5 and 2.15 respec- tively, to drive the invert- ing input of ICll-d. The output, therefore, will go high when the external power does not exist and vice- versa. The 5-volt reg- ulator IC12 provides the circuits with power as long as it is supplied with at least 6.5-volts DC or 7 volts AC RMS. A provision has been made for future interface with external hardware on a three-line serial com- munication; see pins 2—4 of connector J2. Also, ground and V^c is brought to pins 1 and 5 respectively. The connec- tion of a battery to pin 7 is optional; when used, it ensures proper operation during power Interrup- tions. Construction Construction of the card is straightforward. Figure 4 shows a parts- placement diagram. The PC board can be made from the foil patterns pro- vided, or you can pur- chase one from the source mentioned in the parts list. When building the board, just be sure to install the IC's last, as they are more susceptible to damage than the other components. The only other thing that needs ex- plaining is the bracket that holds the card down in the computer. You must take a "blank" IBM- (Continued on page 82) 46 DATA DISKS: HIGH SPEED DEVICE SELECTION FOR THE 90'S ED PRESTWOOD* TRADITIONALLY. DEVICE SELECTION involved paging through hard copy selection guides and data books until a suitable device was located. Now. with the revolution in electronic data processing, the technical community is quickly moving toward high-speed com- puter-assisted software for select- ing semiconductors arid other electrical components. The pro- cess is not only faster and sim- pler. It also results in better device selections. Wliat began as a simple foray into PC -assisted device selection is rapidly becoming the preferred method of device selection by to- day's engineers. For one thing, data disks routinely save users hours in the device- select ion pro- cess. Second, and perhaps even more important, there's a tre- mendous cost advantage for en- gineers to design in components that not only perform well, but are cost-effective as well. Select- ing the ideal device at the best price often results in the savings of thousands of dollars for com- panies that take the time to op- timize their designs. Some com- panies are even using data disks to find better, less expensive re- placements for components in existing designs. What are data disks? Data disks are selection guides on floppy disks. Manufacturers are now providing data disks to •Ed Prestwood is president of CybersoR, Inc. . a Tbmpe, AZ company specializing i n the production of data disks. customers as a supplement to conventional literature to speed up and simplify the device selec- tion process. Data disks are not intended or designed to replace data sheets; instead, they are computer-assisted selection guides that recommend several suitable devices for the user's ap- plication. They run on popular PC's and help users select the ide- al device or product for their ap- plication in seconds rather than minutes or even hours. Some data disks integrate cross refer- ence support for as many as 27,000 competitive devices. Finding tfie right component for a particular application is easier than ever, with the help of today's data disks. After the data disk recom- mends several suitable candi- dates, it's up to the user to obtain the appropriate data sheet to make a final intelligent selection. To make it easier to order the proper literature, some disks even contain listings of technical literature for the devices on the disk. The Motorola data disk, for instance, lists every application note, article reprint, engineering bulletin, training course, data sheet, and data book available for over 13,000 integrated circuits and discrete semiconductors. What do data disks do? One of the simplest functions provided by these electronic se- lection guides is the part number search. Users enter the device number they are interested in, press the Enter key, and the pro- gram conducts the search. When the part is found, all information concerning it is displayed. The more sophisticated disks auto- matically search every product category on the disk for a spec- C/J m H m 03 m (C O 47 w o z o cr H O UJ ified part number. A useful varia- tion of the part number search is the partial part number search. In a partial device number search (also called a substring search), the user enters a portion of a de- vice number — "6800," for in- stance. The program then locates every device that contains "6800" somewhere in its part number and displays the list in a tabular format on the screen. One similar feature is called the complemen- tary device number search. This option will locate the electrical complement for any discrete de- vice specified by the user. A few of the currently available data disks provide a useful cross- referencing feature. If the spec- ified part number isn't on the disk, the program automatically looks for it in a special cross-ref- erence file. If it's listed, the soft- ware automatically looks up the manufacturer's equivalent device and displays the information for that device. Some data disks tell users if the cross-reference de- vice is a "similar replacement" or a "direct replacement." The Har- ris Op Amps data disk even tells users about the pin-to-pin com- patibility and the degree of elec- trical equivalency. The Harris disk also provides comments re- garding the suitability of the de- vice as a substitute for the requested device number. For most users, the most valu- able capability of data disks is the parametric search function. After this function is selected, the program displays a menu of parameters for the devices in the selected product category. Users then select the parameters for their application from a menu and enter minimum or max- imum values appropriate for their application. Some data search disks provide pop-up menus that list choices for pa- rameters such as package, tem- perature range, Zener voltage, etc. After entering the values, pressing a single key will display aU the devices that meet or ex- ceed the specified requirements. Like any good spreadsheet, the better data disks allow users to conduct "what if?" sessions. High-end data disks, such as those developed by CyberSoft. ac- tually remember the previous pa- rametric search and permit users to conduct the search over and over, "tweaking" just one or two parameters with each pass. That permits users to make whatever compromises are nec- essary to optimize the cost-per- formance tradeoffs. Data disks also provide a host of other features, such as the ability to limit searches to mili- tary components, surface mount components, or military surface mount components. Many data disks include a printable "Infor- mation Request Form" so that users can order technical liter- ature and sample devices. Most data disks also contain sales of- fice and/or distributor contact lists. Help files, screen-color util- ities, and printer utilities (in- cluding network and spooler support) are also available on some disks. The Burr-Brown data disk even has a provision for displaying new product informa- tion that users can download from the Burr-Brown BBS in Tbc- son, Arizona. Thoughtful man- ufacturers also include a phone number for users to call to obtain the latest versions of their data disks. Many offer free subscrip- tion services. Are all disks created equal? By no means. Several of the data disks available today are highly polished, professional software packages. A few, how- ever, carry the mark of the novice. The differences matter little, however, when a manufacturer SOME AVAILABLE DATA DISKS Analog Devices Two Technology Way Norwood. MA 02062 Bill Schweber (617) 329-4700 CIRCLE 225 ON FREE INFORMATION CARD Best Power Technology P.O. Box 280 Necedah, Wl 54646 Literature Center fSOO) 356-5794 CIRCLE 226 ON FREE INFORMATION CARD Bourns 1200 Columbia Avenue Riverside, CA 92507 Customer Service (714) 781-5500 CIRCLE 227 ON FREE INFORMATION CARD Burr- Brown P.O. Box 11400 Tucson, AZ 86734 Customer Support (800) 548-6132 CIRCLE 228 ON FREE INFORMATION CARD Guttler- Hammer Dept H293 4201 N. 27th Street Milwaukee Wl 53216 Diane Nuesslein (800) 833-3927 CIRCLE 229 ON FREE INFORMATION CARD Equipto 351 Woodiawn Avenue Aurora IL 60506 Customer Service (708) 897-4691 CIRCLE 230 ON FREE INFORMATION CARD Harris Semiconductors P.O. Box 883, M/S CB-1-25 Melbourne, FL 32901 Literature Center (407) 724-3739 CIRCLE 231 ON FREE INFORMATION CARD Lambda 515 Broad Holiow Road Melville, NY 11747 Customer Service (800) 526-2324 CIRCLE 232 ON FREE INFORMATION CARD Motorx^la RO, Box 20924 Phoenix, AZ 85036 Literature Center (800) 521-6274 CIRCLE 233 ON FREE INFORMATION CARD Newport RO. Box 8020 Fountain Valley, CA 92728 Technical Hotline (714) 965-5406 CIRCLE 234 ON FREE INFORMATION CARD Philips Components George Washington Hwy. Smithfield, Rl 02917 Cindy Taylor (401) 232-0500 CIRCLE 235 ON FREE INFORMATION CARD Precision Monolithics 1500 Space Parit Drive Santa Clara, CA 95052 Ulerature Center (800) 843-1515 CIRCLE 23S ON FREE INFORMATION CARD Titan Severe Environments 20151 Nordhotf Street Cathsworth, CA91311 John Van Putten (818)709-7117 CIRCLE 237 ON FREE INFORMATION CARD Western Digital 17900 Von Karman Ave. Irvine, CA 92714 Literature Center (800)832-4778 CIRCLE 238 ON FREE INFORMATION CARD Xentek RO. Box 1987 Vista, CA 92083 Larry Merchell (619)727-0940 CIRCLE 239 ON FREE INFORMATION CARD 46 has the only data disk tor their given product line. But with new disks becoming available every few weeks, the competition to provide the most convenient and powerful user interface is inten- sifying. All the manufacturers mentioned here have improved their disks with each new revi- sion. It may seem ironic, but to- day and throughout the 90*s, the battle for share-of-mind will be fought and won on the basis of ftlliK CMfcnwti Ifiued: ftbrvirv 1^ y]?al IriFslitpri UEJh . onjfivTiMHL lEidfd Ml SItF tmi ' fTtwtnc*! rjpq* f«n JuflW Is t DJticHtr>3 typM II IBlttfl-tltBt FIG. 1— THE MAIN MENU from Philips Components' Discrete Semiconductors Transistors data disk. the ease of selection rather than solely on the reputation of the manufacturer. A few of the data disks available today provide automatic multi- level sort capability, which is a definite advantage in today's competitive market. CyberSoft, Inc. introduced the multi-level sort feature when it developed the first Motorola data disk in 1987. The multi-level sorting al- gorithm sorts each and every col- umn selected by the user It sorts on the first selected parameter, the second parameter, the third, and so on across all the param- eters selected by the user. The procedure takes place in milli- seconds and assures users that the absolute best device in the database for the specified ap- plication is always Usted first, and so on. The automatic multi-level sort is arguably the very best way to display data. A less useful com- promise to the automatic multi- level sort is the manual column- by-column sort that users can conduct after the search has been completed. One feature users should be aware of is called the "early- abort" search algorithm. Some data disks search their databases and abort the search after a spec- ified number of devices are lo- cated (10 and 15 are common numbers). That's an awful ap- proach to searching a database. since the 16th device- — or the 2,016th, for that matter — may be the ideal device for the specified application. Look for disks that search the entire database for pa- rameters selected by the user, then report back the total number of "hits." The best way for the software to "know" how many devices meet the user's re- quirements is by searching the entire database. Another very useful feature that separates the men from the boys is called parameter queu- ing. That is, the program auto- matically displays the param- eters in the same sequence that the user selected them in. If a user selects rpgj^,^, as his or her UrlcoR it MvtWi [rLltqrtlnJ CjroJits Blt> lisfc %mii v> ; IP Edit IP = PrixUi tiiwna = '[ Ajt«otL« £EKlroni« I. CnwiiLEihcw Cirttiits J (Oil. a. mi KPi Uti Coiucn! 0. mait 9 tining Circuits CqniTDl FunclLom t fvm ^ ItttE' of tlv dKirid uliwj. Fmi CHS far hii^litfitKJ opt inn. f Prtii fttfl jiifirl iCTWfi: frtnM Tbt ujIdps * htt» IS fv P^rtviM scrwi. Ijfor Ltit Sctht: Ij tzr Hiin nm. FIG. 2— MOTOROLA'S IC data disk gives access to a wide variety ot product cate- gories. most important parameter, it is displayed in the first column. Likewise, if the user specifies breakdown voltage as the second most important parameter, it will be displayed in the second col- umn. Automatic parameter queuing, coupled with automatic multi-level sorting, provide users with the most useful and conve- nient display sequence possible. Burr-Brown, Harris, and Motorola support both of these important features in their data disks. Data disks also vary greatly in the amount of data they store. The number of devices is not a reliable indicator of the amount of information contained on the disk because there may be only five or six columns of informa- tion available for each device, CyberSoft, who developed the Burr-Brown, Harris, Motorola, Titan, and Western Digital data disks, supports up to 64 columns of data for every device, which can add up to a lot of data, A final consideration when gauging the amount of information on a disk is the number of cross references supported. Motorola's data search disk contains well over 25,000 cross-references, which can be a great convenience for de- signers and technicians alike. Some data disks include pric- ing information. Most engineers insist on seeing price informa- tion, even if it's only "ball park" pricing. Relative pricing greatly simplifies designing to a budget. If two devices will work in a spec- ified application and one costs half as much as the other, it gen- erally pays to take a good look at the less expensive component. Some disks, like the Titan Data disk, provide users with volume pricing based on the quantities ordered. One other feature that appears only on high-end data disks is footnote support. All too often, a device that looks ideal may be in- appropriate because of some sub- tle characteristic that isn't ob- vious by looking at the tabular Ibbii iii.tii;:iiiimii«iiii,ui;it.-iitSTOi;aii!iMia m\ Firiiwsf .mstcK Iyp« of Solulicn Erjftucs Bivict l^HCTipt jffi . . . ,&tinad US Coitii Ulf EK^ro3&9J jCN6 liBl JStt^lllfel ., Blttriil H»l I ] il ' Biin llwn- a ' hinl- t ' Htlj. 1 = Dii- StTm. S 'U\t. j FIG.3— A SAMPLE DEVICE INFORMA- TION screen from Western Digital's data disk. data itself. All data disks de- veloped by CyberSoft provide ex- tensive footnoting capabilities. Another important thing to look for in a data disk is good customer support. Some compa- nies, like Burr-Brown, Motorola, and Western Digital, are placing their data disks onto corporate Bulletin Boards so users can download their latest data disk { and/or new product updates) in minutes. Others, like Equipto, provide a dedicated customer ser- < vice number that users can call, f^ Within minutes, Equipto sends ^ FAX information on any compo- g nent covered in their data disk to ra their customers, Equipto's disk, i coupled with their dedicated sup- 5 port line, has not only dramat- c ically increased sales leads, it's also propelled Ihem into a record sales year. Who's offering data disks? Over the past four years, a number of companies have pro- vided data disks to their custom- ers. Disks are distributed at trade shows, technical colleges and universities, and through "shareware" catalogs. More and more of the 6,000+ bulletin board services across the United States have data disks waiting to be downloaded at no charge. The following list shows a sampling of the data disks that are free for the asking. • Analog Devices — This disk pro- vides pricing information and covers Analog Devices' line of op amps and data conversion cir- cuits. Disks containing SPICE emulation models for Analog De- vices op amps are under develop- ment and will soon be available. • Best Power Technology — ^This disk, available in English, French, German, or Spanish, is a "brochure-on-a-floppy" for their broad line of computer- grade un- interruptible power supplies. • Bourns — Bourns "Selectrim" data disk provides coverage for Bourns' complete line of trimmer potentiometers. • Burr-Brown — This data disk covers Burr-Brown's entire line of op amps, instrumentation amplifiers, isolation amplifiers, analog circuit functions, D/Aand A/D converters, analog circuit multiplexers, sample/hold ampli- fiers, voltage-to-frequency con- verters, and data-acquisition components. • Cuttler-Hammer — Billed by the company as an "Expert System" program, this data search disk leads specifiers through a series of pertinent questions that re- sults ultimately in the recom- mendation of the appropriate photoelectric or proximity trans- ducer for a given specified ap- plication. • Equipto — ^The Equipto disk in- corporates more graphics than most data disks. It helps users speciiy the optimal modular en- closure (including vertical racks and slope front consoles) for elec- tronic equipment. Also includes computer furniture, instrument cabinets, and EMI/RFI shielded enclosures. • Harris — Harris' first entry in the data disk arena covers their broad line of operational ampli- fiers, including devices from the recent merger of GE, RCA, and Intersil. Look for additional Har- ris product lines to be added soon. A disk containing SPICE macro models for several Harris op amps is also available. • Lambda — Lambda offers a disk covering their broad line of AC-DC switching and linear power supplies, DC-DC power supplies and converters, sup- plies for laboratory and test equipment, power semiconduc- tors and power systems. It also includes pricing information. • Motorola — Motorola offers two IBM disks containing all the se- lection guide information for both IC's and discretes. These disks operate stand-alone or in concert when copied onto a hard drive. This disk is also available on a single microfloppy for Mac- intosh PC's. It features 124 prod- uct categories, 13,000 device numbers, 27,000 competitive cross references, and half a mil- lion parameters. Motorola also of- fers SPICE models for their power MOSFET's and scatter pa- rameters for selected small signal RF devices. • Newport — The Newport Optics Catalog on a floppy features their line of optical lenses. Includes over 2.100 cross reference prod- ucts for several of Newport's ma- jor competitors products. • Philips Components — This cornpany is offering four data disks, covering diodes, FET's, hybrid amplifiers, optocouplers, power MOSFET's, small-signal transistors, and trigger devices. Competitive cross references and pricing are supported. • Precision Monolithics — The "Precision Decisions" data disk provides data for PMl's IC product line, including op amps, data conversion circuits, and sample and hold circuits. Includes prices and industry cross references. A disk containing SPICE emula- tion models is also available. • Titan Severe Environment Systems — The Titan disk fea- tures the company's full line of SECS militarized and rug- gedized board-level and system products, including microcom- puters, memory, parallel and se- rial interface, bus interface. analog, and peripheral controller modules. The data disk also in- cludes product overviews and general pricing information. • Western Digital (WD)— Pro- vides extensive coverage for WD's line of VLSI chip set solutions for XT, AT, 386 and 486 PC architec- tures, including their Micro- channel products. Prints prod- uct overviews and provides a useful "Related Solutions" sec- tion. WD also offers a two-disk set of utilities and schematics cap- tured using the ORCAD/STD III v3.22 software. This data search disk set facilitates the develop- ment of design solutions based on the AT-compatible WD286- LPM16 motherboard. • Xentek — This disk provides pricing information and major parameters for Xentek 's line of standard linear power supplies. Extreme isolation transformers and switching power supplies will be added in the near future. Gimmick or trend? Data disks have come a long way from the first ones that ap- peared in the mid 1980's. What may have begun as a marketing gimmick is now evolving into a useful engineering trend. Tbday's data disks cover virtually every discrete and IC product category. New disks are also covering power supplies, sensors, re- sistors, VLSI chip sets, plastics, and even optics and lasers. The major force driving the data disk market is that compa- nies are motivated to make it as easy as possible for customers to select and purchase their prod- ucts. The thrust and cut of com- petition has helped create a healthy win-win situation: man- ufacturers view their data disks as marketing tools; users view data disks as time-saving engi- neering tools. Since introducing their first data disk. Equipto re- ports an increase in sales leads from 12,000 per year to approxi- mately 75,000 better qualified sales leads per year! That kind of result, coupled with increasing customer demand for faster, easi- er, and better device-selection tools will continue to assure the proliferation of data disks. For more information, contact CyberSoft, Inc., at 1820 W Drake Drive, Suite 108. Tempe. AZ 85283, [602)491-0022. R-E 52 LAST MONTH WIC FINISHED BUILDING THE MOTWERBOAIiD AND THE motor-controller board. Then we covered the operating theory of the power board. So. now let's get to building whalever we haven't covered yet. including the control panel, power board, and mechanical assembly. Construction Fabricate an aluminum sheet-metal enclosure lo house the control-panel electronics: we showed you how to wii'e everything las I month. As for the manual controller, drill holes in a plastic box to accommodate the compo nents; we showed you a schematic of the controller last month. Feed the ribbon cable through a hole on the side of the plastic box and put a knot on the inside of the box so that the wire can't be pulled through. Fasten the top cover to the box and atlach the knob to the po- tentiometer (PI). Power-board construction Following Fig, 1. mount the following components on the solder side (back side) of the PC board: R42, R52, R54. D7-D9. D20-D29. and all E-ier- minals (they are basical- ly solder posts that allow you to solder heavy- gauge wire to the PC board). Those compo- nents are mounted on the solder .side in order to create more space for the other component.s. It is probably a good idea to add a '/n-lnc'h piece of sleeving insulation to the leads of those components before assembly (willi the ex- ception of the E-termlnals). That will prevent any accidental shorting of the exposed compo- nent leads. After they are installed, trim the component leads. Now In- stall the remaining parts on the com- ponent side with the exception ot the power MOSFET's. The MOSFETs require the instaUatlon of heat sinks and insulators before assembly. For each MOSFET. place an insulator on the F^C board and then cover with a heal sink. (Carefully clip off the center lead (drain) of the MOSFET as close to the device body ais passible. The lead is not usedbecause the drain connection Is also provided by die metal tab on the MOSFET. Bend the MOSFET leads at a 90^ angle and insert into the PC board so the device lies Hush with the heat sink. Secure (he device and heat sink to the PC board with 4-40 hardware. The high-current jumpers should now be installed on the solder side of the PC board; solder them to the E-terminals. Thcjumpcrs are required because the etched traces on the PC board can not handle 15—30 amperes. Thejumpers should be made of solid insulated 18-gauge wire. Figure 2 illustrates the three types of jumpers. Install the jumpers on the solder side Let's mow the lawn already— rather, let's watch the lawn get mowed! Build the Lav\rn tZanger RAYMOND RAFAELS E2a o z o cr H O LXJ o < FIG. 1— PARTS PLACEMENT DIAGRAM for the power board. Remember that several components must be mounted on the solder side of the board to leave room for the other components (see text). of the board as follows: TYPE-A JUMPERS E-23 to drain of Q8 E-18 to drain of Q9 E-20 to drain of Q 10 E-13 to drain of Q5 E'lO todrainofQ6 TYPE-B JUMPERS Drain of Q4 to Drain of Q7 Drain of Q3 to Drain of Q4 Drain of Q8 to Drain of Q14 Drain of Q7 to Drain of Q18 (mount on component side) Drain of Q13 to Drain of 914 (mount on component side) TYPE-C JUMPERS E-23 to E-21 E-18 to Jll-10 E-19 to Jn-8 E-20 to Jl 1-9 E-17to Jn-8 E-14 to E-15 E-15 to E-16 E-13to JU-7 E-10 to Jll-6 E-12 to E-11 E-11 to E-7 J21-23 to J 11-3 E-6 to E-8 E-2 to E-6 E-5 to Jll-2 E-1 to E-17 E-1 to E-9 E-3 to E-4 E-22 to JU-4 E-22 to Jll-5 Grass-sensor assembly Build the mechanical portion TYPE-B JUMPER FIG. 2— HERE ARE THETHREE TYPES OF JUMPERS. They are used to handle the high currents that exist on the power board. of the sensor assembly as shown in Fig. 3, and wire the grass sen- sors themselves as shown in Fig. 4. The length of the ribbon cable that connects the sensor assem- bly to Jl on the motor-controUer board should be approximately 3'/2 feet long. Crimp Jl onto the end of the ribbon cable using an IDC crimping tool or vise. Power-board testing Inspect all solder joints and jumper connections to ensure that everything is properly as- sembled. Place the power board on a flat surface (not plugged into the motherboard} and tem- porarily jumper Jl 1-3, Jll-8, and J21-44 with clip leads. Now con- nect the + 24-voIt input to the PC board through Jll-4 ( + ) and Jll-3 (ground). You should hear the relay "click" on. Measure the DC voltages at J21-32, J21-18, J21-30, J21-31. and J21-19. The voltage readings should match the values listed on the sche- matic diagram that we showed you last month. If all the voltages read correctly, the DC/DC con- verters are working properly. Re- move the test clip leads from the PC board. Mechanical assembly Figure 3 shows the mechanical assembly of the Lawn Ranger. Al- though it does not include all of the details, detailed mechanical drawings can be purchased from Technical Solutions. However, the chances are that you won't follow the original plans exact- ly — just as long as you follow the general layout. Also, make sure that the cutting section is safely constructed, and that the blade shield protects the cutting deck a full 360 degrees. WARNING— The cutting blades should not be con- nected until it has been proven that the Lawn Ranger has been properly constructed, is fully functional, and safe. Many of the mechanical parts are available from various man- ufacturers listed in Table 1. The rest of the mechanical compo- nents shown in Fig. 3 are not avaiiable from TBI; you must ei- ther fabricate them yourself or have a local machine shop make them for you. WHAT'S BEEN COVERED This series on the Lawn Ranger began in the June issue. In that issue, we covered the general op- eration of the unit, the software, and we discussed and built the CPU board. In the July issue, we went over the electronic control system, the motor controller board, DA con- verter circuitry, grass-sensor cir- cuitry, motherboard, and velocity- feedback loops. We gave you the parts lists for the motor-controller board and the motherboard, al- though we didn't get to build them that month. In August, we began with the construction of the motherboard and the motor-controller board. Then we covered the operation of the power board, drive motors, cutting motors, hand-held control- ler, and the Lawn Ranger's elec- tronic control panel. In this issue we have finished up the series. We hope you have found it to be an interesting and worthwhile project. R-E 54 BEctrnmcs® VOL. 1 NO. 1 Executive Offices Larry Steckler, EHF, CET, Publisher Arline Fishman, Advertising Director 500-B Bi-County Blvd. Farmingdale, NY 11735 1-516-293-3000 FAX 1-516-293-3115 NATIONAL REPRESENTATIVE Joe Shere P.O. Box 169 Idyllwild, CA 92349 1-714-659-9743 FAX 1-714-659-2469 CLOSING DATES: Reservitl«ns Final Film )ssu« In H.Y. In K.Y. Sept. 1990 June 11, 1990 June 18, 1990 Nov. Aug. 13 Aug. 20 Jan. 1991 Oct. 15 Oct. 22 Mar. Dec. 13 Dec. 20 May Feb. 13, 1 991 Feb. 20, 1 991 CERNSBACK PUBLICAMON ADVERTISERS INDEX Alfa Electronics 28 All Electronic 8 Andralech 32 B.G. Micro . , 35 Battery Tech 32 Becktron 16 The Book Source 6 Caico International 16 Command Productions 21 Computer Disk Service 30 Consumertronics 24 d b Computer Products 14 D&D 17 Datbani Corporation 13 Davilyn 7 E.T Tech, Inc 26 Electric Raintiow 23 Electrified Discountei^ 11 Electronic Goldmine 19 Electronics Parts Outlet 26 Electronics Clearing House 30 Electronics 12 3 18 Gems Computers, Inc 33 J.R Glaser ,.10 Gott Electric 4 Ttie Grapevine Group 36 Gray Matier 22 IQ Systems 2 Information Unlimited , . , 37 Jensen Tools, Inc 36 Kelvin Electronics 29 L-Com, Inc 28 l^ondo-Tronics, Inc 36 Needham's Electronics 26 OWI 20 Omnitron 27 P.C. Boards 22 Pr^C Electronics 20 Paladin Electronics 34 Periphex, Inc 30 Pfeico 25 Ramsey 3 Sescom 20 Sky Vision 40 Surplus Sales of Nebraska 16 Surplus Traders 12 Tanner Electronics 10 Tecti Ser/ices 34 Top Sales Co 18 TransWorld 32 Ucando 34 United Electronic Supply 31 Universal View ^ 39 Video Repair 24 Viejo 34 Walling Co 3fi RE-SHOPPER THE TymCard® $25,000 CHALLENGE IQ, Inc., in an attempt to improve the security of it's product, offers this challenge: IQ, Inc., is about to release an anti-fraud "smart card" called TymCard, to be used by long distance telephone companies to help eliminate calling card fraud. We believe our product to be unbeatable. To detect any possible flaws in our system. IQ, Inc., is offering a prize of $25,000 to the first person who can demonstrate that he or she has been able to access the system, at any time, by being able to generate a valid code at will. Accessing the system DOES NOT mean "breaking" one or more existing TymCards as that only allows temporary and insignificant access to the system. EXAMPLE :If you knew the numbers of one or more TELCO calling cards, you would be able to make long distance calls that woiild be charged to that card - until you were discovered -■ and that number was deactivated. If ^however, you had a ''Blue Box', you would be able to make calls at aiiy time. You were able to "break the system" without need for any calling card numbers. The only permanent solution, as fat as TELCO was concerned, was to change the system which, in effect , "deactivated" the Blue Box. A condition of this challenge is that you supply to IQ, Inc., the details on how you were able to "crack the system" and assist IQ. Inc., to correct the flaw. Each respondent to this challenge will be invited to a meeting with members of our staff. At this meeting you wiU be given much more technical information about TymCard as well as a description of the service. Please note that there is absolutely and positively no charge to you to accept this challenge. If you desire to "borrow" an ACTIVE TymCard that will allow you to test the system at any time, we ask for a $50.00 cash deposit. This deposit will be returned to you, in full, upon the Tym Card being returned to IQ,Inc., as agreed. If you are interested, please call (818) 592-0423 for information as to the time and location of the next meeting. ^''^ ''' NOTE: If jfou are not located in the Los Angeles area please call the number to arrange for complete information to be sent to you by mail. 2 RE-SHOPPER ^ ALL NEW KITS • 2 MTR & 220 BOOSTER AMP Hsres a great booster tor any 2 meter or 220 MHz liaiKl-held unit. Th&se power boosters deliver over 30 watls o( i>LJlpiil aliowingi you lo hit the repeiier5 full qutetirg whik (;he low noise preamj] remarkat}lv improves recep- lior^s. Ram$ey ElectrorJics has sold thou- sands of 2 mu amp kits but now, we offer compleiely wired amj tcsjed 2 mtr as well 22C hTHz units, Eikith have all the features of the high priced boosiers ^t s fraction of the cost PA 10 2 mi POWEFt BOOSTER (10 X power gam] Futty Wired i tested S79 W f^ZO 22Q MHz POWER BOOSTER 4e X po^er garni Fully wrred fi lested ST^.dS (^ f% 1^ • 30 w*ns OUTPUT • LOW KOtSE PHUMP • LOW COST • RUGCES CAST ALUMINUM CASE • OHEVEAKWAIIMNn SPEEOY Comi^lEJt 1 PERSONAL «on nc SPEED <89.95 RADAR N^N low tcisi nvicrDwavc dQppicr ^lOai kil 'docks' cati plir>f5 EwAti rioijw bikts thf&Eb'iiT mosjii mnntrsor virludlJr an^lliinf iJiit movts OperHtsal Zi^i wilhi Ovcf E M m lie r^ngE L E:Cf d igil^l THtT-IHit diS^^yi S.{>Hl3s i n mifES [Mr hour. kjiomdBis per tiwjEflr 1ki prr mwi>i1' Ea'phDne output pcrmils liilcji'ing Eo aduiai QDppkr shi1l tj«E:S cn'[» 1 1t cortre can) Td-r jntenni mot iiKiudcet ana mmar ^2 VtJC Eaiy lo EHjila- jii niic'iji«vcf:Lrci.i!rv is PC (iJiQEiM Kii incUiduaeihiic ABS pJasUtcau wMft speedy i;raphiQlOi«prOJ»b'OH«IIOdl: AvCryuuMUKl lutl-ol-lun Itii RADIOS 20, 40 & 80 MHERS HAM HECEIVERS S<[ivi!i>ire all riKidt J^U.CM ^SBTKeivtfslat^^— ^'D'orii'^^^MHi Clirecl cdnutmon dM»gn using Uiffl2fCii fti\hitc in QST imd ARRl Tu^ti^k; L(» mjn 1 ^v HnsiENity vjf aclar difltfe itjnfij. 250 mw audio output Runsangvrc na^RFgaincfitiiioi lr*isi(iti$v(»yfrasy(g burld lols ol lun jnj EdL-cjEion^i— ,{iEai icr the iM^irntr or 1^ q|(| p^u T!iF(ij>iiDnal tnaEciung use kil 1» lulls a ^uggcii AB£ plastic cas^E lAnit] scretnied graptiici indutlied ant macrnrved aKimanuni tnain tpr 1 iiVEll-linijhcd pr>alessii>iiil loo^ aunt «>tfTn nmn SS^ *24.95 S^ *24.95 JSISI *24.95 ^ *1^95 QRP TRANSMITTER KITS, ZOv 40 & 80 METERS l}]Kratf a min lum shiack Tiicse IctileCW rig^arc loeal matei eo our 40 an40l>T«ier rvumn Futurn ineMc sihmIA varubltluitirig {yre wait output imf ExcelknE ktyini) CFiaract'Sristici (bins an 12 VDC vvi m VSWR pralKleC ^ec ttErw Ear |«ican slrElcti youric^nal witli{>nE 0I itiErsr mini rigs Ojitiorai ABS cati at available SgiiTR 4(iyTA WUTR C»4 a^" »29.95 gg^ »29.95 ^ ^ »29.95 S^ M2.95 AIRCRAFT RECEIVER KIT Heir bxniuij airca~alE communicatiocit-pitksup f^lanesuj^lA 100 mitK 2iv2v FlHCives IIQ— tX MHi AM iiT band varactor iuicd luiwrticE design w>tn ACC. ccraKniidiller and adtuslabte 3<>Mlcn AunjiDnaVbaiiery^SSOniw audi4]'W>ipcil ^jjvsfn^tivtty Optional matcniiiQABSplKEic Uh iths ypu like H aortttvErF. tEalu^es^ittEjenei] graptiiti and macnined alcjininEjm knobs tor a fcal prolessionat look Compact-'grcat Tor airjnowi i^r tor |u ji plain tiinqing around Ihe airpixtj cttip Eor }e» man a microvoli sEnniiv- Hy, runscKn Wbittc'v This is a lascinaiing scoul. KhooEt^f oiub prDiEct. and will provide houet ol Jtjftevcn 10 int mtrit ittmiCxv Add me op^ionatcasE Kit jnn you t\Mvt a lEai mcE looking shoriwa^sei compieie kiE.Sft'l 124.95 Sf'cs"',"" *12.95 PACKET RADIO Cofn'ncd&rc C5J/ TS pacnEWMio tntirtacc Us« ramousGcrnvan t]igcMesFRE8disksCil|ware PC boartf alintctssary pjMsarxltuMjicumenialion ^jtt% AC CoTHiMUkil.PC-i *4Ii.33 FM COMMUNICATIONS/ 2 MTU 10 MTR & ^0 RECEIVERS S*ns«W( iuperhfti fu recei^r isiim any 5 MKi segraent of bind. Uittn t* ham otufatrans, liigti. bvid polite ciHi. wutlw or T«tilfi fMwH calls! Eaiy tit bui^ rbceivBr luluret varactof tiiTting. C muw itaQH, anmc IF filur^and duail ccnviFSion $«$jgii wjCn adjujuiM squckh, Uu man "l ij^ Mmflivity, ruris CK^ 9 V b«t^, wnh 50 rina iwtia wipui. Op«^ wrtii K^Hfwt gnpAin and rruchintdiKiminum kmntn pnvidi a niu prohsiCMul took. ZHm tiUTA aoiMt hwwr ^7 *2935 ^. «293S ^ t29JS ^r" *IZ95 NEW MINIKITS-NEW MINiKITS BROADBAHD PREAMP A stnsilkvt all purport pftamp xfe^L for stannen.TVMlvVHF dHF f ms, iffiunitrj Ht ftjiureiicw noise ^db M=.?0 Obtain. 100 KhU— iG^ofrirjTion Htuiso(i9-T?VDC.50 itt\fr.i. input LIGHT BEAM COMMUHKATORS Eransmils m«l(ilal(>d inlnrtd |jg|jv • 100 KHz to 999.9995 MHi ContiriiioLis frequency coverage • Transmit protecllon. up lo 100 walls • CTS tone encoder, t KH; and exlemal modiilatlon MINI KITS-EASY mMSIIflBLE-FUN TO USE Acoinpitie tonetfccMfj!' -^ ^astnglePCtKiafd Feiluie; VSi-^OK Hz aijui\s.b\t ra[>jM via ^ lu m piM . volf age Tt!gu^ati«t) $9,95 &Krmjsiccornea]ive'i3 di11( rent lights rihCkFr wilhmusio dnelighE Eaciilor. hign nudrant;^ anQFDws. taciiindividU' altjradiusEableand KriveiuplaSOaW runs OR 110V*C Mil Kit $8.^ VtKEACrmiTffl Vot^eacTivaiEdswatcn littprfiv^tlKSWilCtttd OUlpUlHrilhCUrfEirlEJ iUtKkLfUpKllfiOinA Cand'ivertlayj ligiils. LED or even a tape lEcorder molar Runson 9VDC VS-UII S&.^ TELEPMME TMlftMirTIH LowcDsl With proles ' sionaipfjformance Fu- lurrsinclude. sell phone iinepowerfid, lunabFe Irom^EionOlMlHz, polarity annsensmvE compjctsiJEt ,''xl'-'l easily insLAlisanywlHiB on me phone line or iniidfrEhtinstruirnejil lEseti Pfl-IKIT S 14.95 yiOEOMOOULArOM r TV Ig video moniHN Super uonvc'Lianv TV Ig video moniHw Super ^^^ -j^ Enable tur^AbleovE^ChJ-^flcnsonS-lW {»f£.3i] a-cccptssid video Signal Bt&tuniEArithe [JiJrktEiCflmpklekn JM.? UIMJIKYKIT AlEErhat1SF/ltashK2 jumooLEOs UielQf njmE badges buEtoni. ivainingpaiKlliQhl$ fiunspmSlolSvalti. Si^\^vi S3w95 ProvKtes the basic parti andPCEK>ardrBfluiredHk prnvHTeaS'Purceorpre- Cis>c»niiinhr4 and pulse gEsieral'ron Dies 5f6 lifPEi'iCaiKiiiKludKa range of pans igfmos'l limmqnEHJs ^^ UMKii M.9S Fmrocmit F>3^9urll inapploUoni orn^iti&yexpertmerii^a^ lion Full lt«Jgetegr4ied Circuit deteclor.Umvir audio ampliilier.^ exleTnalpoinersfhirce. operation or stu>dard FMbrv^caslbandU Will IS large portions 041 eachside, c:ofnpac:i|ie~ HfUjrei.foirbugdElec- lioitorreceptioi^ """ S14.95 KUHAtTU Produces LdUOeir shai- lertitgandalEEniiohgeE- imgsiiEniikesofjud Can supply up tots waits oE oPimiiDus audio AiMts OnC-lbVDC MB I Kit S4.^ AnmtEiesticigkil. small irnkt picks up sounds aridconvEftsthimo Itpht TlH louder tlH SDu lid. ine Siguier ttoE l^ht IhEludesmikc, cU MMS CT-ia WHt-iacHi <:iSiKvestaiituHt«rm<.»t3iuiii> ig lifi. • Hi MoA rim H ■nf.ui iva >m miae • tlDOl • Inlfi lit ISSk nrUo Ul • Oe M u u ^ la uM Mit • Kttrt ■«■ nun IM U n • HT roMMl IN 7S uln tu • n (m •n ■■»■>■ dtu • 1 pa ml tain nMiMiinMipn. PHONE ORDERS CALL 716-924-4560 FAX 716-924-4555 RAMSEY ELECTRONICS. INC. 793 Cannlns Parkway. Victor. NY 14564 GOTT ELECTRONICS COMBO PLUS by AST RESEARCH INC. $29.95 Memory Expansion & I/O Board for IBM PC, XT & Compatibles, reat- time Oock-Calendar with battery backun RS-232C Serial port, parallel printer port, SuperPak™, SuperSpool™. dock software, and the RAM CLEAR memory initialization utility program (available with 64, 128, 192, or 256 kilobytes of RAM memory $9£>0 per 64K increments. Six PACK PLUS $39.95 Same as Combo Plus but expands to 384 KB of memory SONY BAHERY PACK NP-11 $39.95 (9,6V, 1 000 MAi) for laptop computers and camcorders, nickel-cadmium battery ASYNC CLUSTER ADAPTER by AST RESEARCH INa $199.00 Multichannel Board providing four individually addressable RS-232 Serial Ports on IBM PC/XT/AT and compatibles {uses AST- FourPort/XNTM Enhanced Xenix™ Communications Version #2,0) (ASYNC CLUSTER ADAPTER Cable additional $15,00). 1/4" STREAMING TAPE CONTROLLER by ADAPTEC, $33.95 SCSI to QIC-36, Model ACB-3530A (Manual $5.00) FLOPPY DISK CONTROLLER BOARD $19.95 Dual 360K or 720K switch selectable BEZEL $2.00 For full height tiard drive, black with nedangular LED lower lefthand cor- ner, double-sided tape for mounting, 3-S8"x5-7/8" USER PLATFORM ARRAY $499.00 10 MW HeNe Laser, power supply, 2 beam splitters, 5 front surface mirrors, AO modulator, AO driver, polygon scanner, photo detectors, 3 special lenses, polarizer, over $5,000 worth of optical components plus documentation, Sdd many of these to Fortune 500 companies, universities, and research labs. Applications include research, design and engineering. An experimenter's dream. NEW! NEC 10 Mil HeNe LASER Plus Power Supply $200.00 LASER POWER SUPPLY $39.95 Semi-kit, Units removed from laser video disk players, comprised of power cable, transformer and circuit board. Will power 1 to 10 MW HeNe laser. Excellent bargain. SHARP USER DIODE $8.95 LT1022MC, 5mW at 780nm, single transverse mode. MIRRORS, PRECISION FRONT SURFACE For use with lasers, 13.7/8"x1-3/16" $7.00 19-1/2 "xl-5/8" $10.00 GREEN FLUORESCENT TUBE for scanners STAGBSTUDIO QUARTZLINE LAMP FEL(QIOOOMCL) 1000W, 120V 3200» INTEL 27128A-20 EPROM (New) INTEL 2732^3 EPROM (New) INTEL P-8031 TRIAC; Hitachi FSM16F4 400 volts 16 AMPS $2.00 $9.95 $4.00 $2.00 $3.00 $2.50 DIODES 6A 200V Motorola Part No. MR752 30 tor $10.00 RF CONNECIOR APPLIED ENGINEERING PRODUCTS $2.50 Model 2005-1551-003 GOLD WIRE WRAP SOCKETS 14 pin-10 pcs/$5 16 pin-10 pcs/$6 SOLID STATE REUY, CRYDON D1240 $19.95 input 3-32 VDC, output 120 VAC 40A BIPOUR LEDS 10 PCS/$6 MOTOR, AIRPAX $9.95 120VAC 60Hz 2-12:1 gear train, toothed pinion COMPUMOTOR:MOTOR- CRYSTAL DRIVE SYSTEMS OSCILUTORS $1.50 Model M57-83 $ 773 8 MHz, 13333 MHz, .. ^ , .XC-, ^r,-, t Q/io 14364 MHz, 15 MHz, 25 MHz Model M57-102 $ 942 36.037. ^Hz, 49,7664 MHz Model M106-178 $1696 50 MHz, 51,04 MHz, 75,6 MHz VGA RT. ANGLE PC BOARD MOUNT CONNECTOR Hi Density DB 15 10 pcs/$10.00 COMPUTER POWER CABLES BY BELDEN $2 10 AMR 18/3, 6" TOSHIBA T3100 EXPANSION INTERFACE PA7313E $99.00 EXPANSION BOX PA7310U $299.00 Interfaces Tosliiba laptops to IBM BUS to use IBM add-on boards, LCD DISPUY (MODEL LM585) BY HITACHI $199 640 X 200 Graphic and Aipttanumeric LCD DISPUY (MODEL EA-Y40025AT) BY EPSON $35 40 characters X 2 lines POWER SUPPLY 9.95 For computer related equipment, Input 120V AC, 60Hz, 30W; Output =5V 00, 1000MA. +/- 12V DC, 200MA CCD DOCUMENT SCANNER $39.95 Uses a 4096-element line imaging chip. Can use for robotics, astronomy, machine vision, high resolution slow scan TV, etc. Sup- plied with documentation, STEPPER MOTOR $29.95 By Oriental Motor, Model if PH566-A-Q5, high precision, 500 steps per revolution, O.TS^i per step, HITACHI LCD DOT MATRIX LM215B $29.00 Graphic and Alphanumeric, 480 Dot(W) x 128 Dot{H) High quali^ device easily interfaced with microprocessor. Bit map graphics and text. Other ap- plic^ions possible. Driving voltages available at microprocessor port, CMOS/TTL compatible signal level, built-in RAM for display data storage, built-in CMOS LCD driver and controller, supports full ASOl and extended character set, character size 5x7 or 7x9, dimensions 10,6" L x 43" W x 4/100" D HITACHI DIGITIZING TABLET HICOMSCAN HDG-111 Input de^ce through which graphic data is input to a computer, 11" X 10" Dimension $199.00 4-Button CURSOR for Digitizing Tablet $29.95 Manual $5.00 EDGE CARD CONNECTORS 22/44 Connector, ,156 spacing 10pcs/$7.50 25/50 Connector, for Apple 10pcs/$10.00 COAX CONNECTOR Part #CP-N1 $1.50 MONITOR BOARD WITH POWER SUPPLY/HI VOLTAGE $7.95 Video, brightness, focus, vertical, and horizontal with flyback transformer and high voltage parts. Model 99-0493-001 rev D Replacement CABLES for IBM-like keyboards $2.99 APPLE MANUAL (LaserWriter and LaserWriter Plus) $5.00 WATERTIGHT AURM BELL $19.95 By Henschel Corp., Type taBID3, size 3", 24V DC 5 LB. SOLDER $25.00 Wire, Rosin Core, Tin/Lead 60/40, Flux 2.2%, Dia. ,036 (20Ga} HARD DRIVE CONTROLLERS: Western Digital ST-506 (10-200 Mb) XT-WD1002A-WX1 $29 AT-WD1003WAH $39 HP NUMERIC DISPLAY 5082-7300 $4.95 DATA LINK CONNECTOR $7.75 (AMP Part #501 1 07-2) Fiber optic field mountabie connector used with 125 NM fiber clad OD. This connector mates with AT&T 40 MB/s and 1 MB/s data link products. AT&T F, Eq, Ref. No. 1005B, AMP OPTIMATE FIBER OPTIC CABLE ASSEMBLY $49 with Biconic Connectors (AMP Part #501450-2) 5 meters long, SYMBOL LASERSCAN 2000 VISIBLE LASER DIODE SCANNER $899 Hand- held point-of-sale bar code scanner manufactured by Symbol Technologies, Inc. ORIGINAL IBM MODEL 1130700 COMPUTER PC POWER SUPPLY $19.95 63W 115VAC. ORIGINAL IBM MODEL 154001438 COMPUTER PC-XT POWER SUPPLY $29.95 130W 115V AC. RE-SHOPPER LASERS Laser Platform Array Kit Price $499 Can be used for research, design, and engineering in the medicai, irdustriai, and educational sectors. An experimenter's dream in the fields of holography, interferometry, graphic arts, light shows, and projection. The Laser Deck Consists of: Q A /O milliwatt (maximum output) Helium-Neon laser tube (NEC Part #GLG 5261} which emits a red beam. The tube is hard seal and 15.5" long by 1.75" in diameter It is mounted by two transi/erse mounting fixtures. Q The laser power supply (NEC Part #GLS5281A) powers the laser tube and has an input voltage of 115 to 120 VAC. Output sustaining voltage is 2800 to 3300 VDC. □ This unit sits on an 18.5 lb precision cast aluminum plate. Q The acoustic-optic modulator (NEC Part #0D8813A) is a 140 Mtiz broad band amplifier and will take TIL and video signals. The A-0 driver is on the deck also and requires 24 volts to operate. Q The polygon motor unit (Mir: Japan Electronics) is a ten-sided first surface mirror mounted on an electric motor that spins at approx, 26,000 rpm. The driver for the polygon unit is on the deck and requires 24 volts to operate. Q In addition to the main items above, there are (5) special surface mirrors, (2) beam splitters and (3) special lenses all attached by optical mounts which guide the laser beam to various sensors and places to give the desired result, a reproduced copy of information. □ We have available an excellent 24 volt LAMBDA™ power suppfy at 49.95 that will power both the Acoustic-optic modulator and driver and polygon motor unit and driver. Laser Beam Modulator $398 mcUOIS tube of Z5 ss.oo (Acoustic-Optic Modulator and Driver) Tri-state switch, CMOS COMPUTffl POWER SUPPLY 130W115VAC IBM-XT Model 1501438 (■h5V, -^12V, -5V, 12V) These are brand new supplies. They make an excellent viforkbench powersupplyforexperi- menting. They can also be used in XT comput- ers and other electronic equipment. Priced to move Argon-Ion Laser (Air Cooled) $2995 These lasers emit visible blue and green lines. Power output is llOmiW, They are re- built with brand new tubes and power supplies. Manufactured by a major laser company, they are excellent for laser shews and holography. These lasers are guaranteed for one year. NIHTEHOO CAME CONNECTOR $9.95 The black connector inside game unit that game cartridge fits into. Often needs replacing when cartridge makes intennittent contact Almost impossible to get POWER SUPPLY $9.95 Btkor Corp. LBA 5-6, Input 115/230VAC, 47-440Hz, Output 5V DC at 6.0 AMPS. HALOGEN LAMP S2.8S Toshiba JH115V930WK1 A, 17" long, 120V. HP 1Q-ELEMENT BAR GRAPH ARRAY $Z.DO HDSP-4S20 (red) HITACHI DIGITIZER «99.00 Comscan HOG- 11 1 , grid board/mother board, no plastic case, you build the case. Standard serial interfac* (15" X 15-1/2"), works on a PC, IC SOCKETS ■ $1.00 40 pin, Robinson-Nugent, tufcie cf 10 MICRO-CQHTROLLER- 30148 $1.50 ROM is already pn)grammed-you find a use, we've got 40K of these! HITACHI DIGITIZER $199,00 HDG-1515BN-C, grid board/mother board, no plastic case, you build the case. Standard serial interface. Runs all versions of autocad. Cannot be used with mouse emulation. Gott Bectronies canies thousands of parts, i.e., lasers, optics, electro- medianical, electro-optk:, power supplies, computer related materials and general electronic suppliies far too numerous to llsL In order to better serve you, watch for ou highly inrcvalive twlletin board catalog ordering system. Coming soort, . .contests with prizes and giveaways. Have excess inventories to sell? Call us or FAX us your lists. Need special parts? Let t£ Know. 1 2-9 .... 10-25 .$29.95 .$25.00 .$20.00 CABL£ NAILS by the box WOW! Black or White Each box, 100 nails. #814W-AB13mmfordual RG-59 cable, f^anufactured byABERDEEW. Used to tack when running cable. They have a hardened nail and tough plastic construction. 1 2-9 ,.„ 10-25 $2.00 .$1.50 .$1.25 The REAL THING HARDTOHVD The complete IBM D0S3.3 manual in Spanish. Excellent for the bilin- gual sctiQois and trade schools. We had a hard time finding these, so let's just blow then out to you. 1-9 10-49.., 50-99... 100-up, $17.95 .$15.00 .$12.95 $11.95 EL DOS de IBM es la base para miles de programas de apllcacion. Muchas factlidades sn el manejo de datos estan a su disposiclon. ¥ usted puede desarrollar nuevas aplicaciones en una amplia gama de lenguajes da programaclon so- portados. COMPUTHl SWITCHING POWER SUPPLY 63W115VAC IBM-PC Model 1130700 (+5V,+12V, -5V, 12V) Brand New Supplies. Good for the workbeich. Can be used for external drive. Full of good parts, 1 ZVDC fan, caps, tran- sistors, etc. We hawe over 1 ,000 of these units. Priced to move. 1 2-9,..,, 10-25. $19.95 .$16.95 $14.95 POWER CABLE 157" Long, 115V 20A l't/3 grounded 3-wire, Male plug one enti, other end 3 wires. Black. Can be used on power tools, air conditioning, electrical appliances, and wherever.Thesearerealbeau- ties, difflcull to find. We have over 4,000. 1-9 $5.00 10-49 $4.50 50-99 $4.00 IK $3.00 riRnPR^S • COD, Castiier's Check UnUCnO ■ ^^ ^Q^ey Order Technical Support (213) 316-0916 FAX: (2131 31B-9189 I 24-HOim DBDB Lit: 800-544-1244 | $15,00 minimum oreer CA residents aM 675% GOTT ELECTRONICS 2227 DuFoiir Avenje, Redondo Beach, CA 90278 CIRCLE 344 OK FREE INFORMATION CARD RE-SHOPPER Amazing Pocket Reference! 480 pages of tables, formulas, & conversions and it fits In your siiirt poclcet! {Size 3.2" X 5.4" x 0.6") 7^ 0n€JA- mEW RELEASE! ^'» €very engineer, geologist, man- ager, foreman contractor, purchas- ing agent. maintenancQi person and^ ^craftsman nsedethis bo'^*' ' ; ;» A must for everv studeni, '}> The handymqff «. tiwam I iOQ% MONBV SACK QUABAN7BB ^FNOT COMPLBTBLV SArfSflBD ! * Plus shipping and handling and Colorado reside nts sales tax. See order form below. • Air Profiortlos of Air Dansity of Moist Air General Gas Laws AirToolCFMvsPSI Air Hose Friction • Automotive Antifreeze Table Spark plug Torques Battery Charging 01! Viscosity vs Temp Tire Size vs Load Rate Tire Manufacturer Codes • Carpentry and Construction Lumtsef Sizes & Grades Hardwood Grades Wood Characteristics Plywood 6 Panel Grades Floor Joist Span Limits Insulation R Values Concreted Mortar • Chemistry 8e Physics Elertjent Tables Periodic Table pH of Acids & Bases Elementary Particles Radioisotopes • Computers and Printers Computer ASCII Codes IBM® PC Error Codes IBM® Interrupls-IQ Map IBM® Memory Map 80286 Hard Disk Types Printer Control Codes Cable Wiring Modem Comrruinds • Electrical Eteclric Wire Size vs Ixiad Copper Wire Resistance £(ectric Motor Specs Wire Classes & Insulation Wire Color Codes NEMA Motor Frames Wire & St>eet Guages Elecirio HP WB Torque Resistor Color Coaes Resistor Standard Values Capacitor Color Codes Pilot L^mp Specs Fuse & Battery Specs RF Coil Winding Data Wire Size vs Turns/Inch Wire Size vs Voltage Drop Ampacity vs Temperature Decibel Tatiles Electric/Electronic Fotmutas • General Information us & state Holidays Signs of the Zodiac Flowers of the Months Anntversaiy Names Radio Alphabet Morse & TEN Radio Codes Paper Sizes (InU) Mifitary Rank & Grade State Information Climate Data of the US Time Zones of the US Time Zones of the Worid TeiephoneArea Codes World Airport Etevations Lost Credit Card Phone #'s Airiine 1-800 Phone #'s Temperature Conversion Sound Intensities Body Weight vs Height Wind Strength Scale Wind Chill Factors Firewood Comparisons Fr^uency Spectrum Sun & Planet Data • Geology Mineral Tables Crystal Systems Mohs Hardness Scale Earthquake Scales Geologic Time Scale • Glues, Solvents, Paints and Finishes • Hardware Bolt Torque Tables Wood Screw Specs Sfteet Metal Seres Specs Nail Sizes and Welahls Wire Rope Cat>le Clamps • Math Inch-Foot-MU-Drill Numt>er Math Formulas & Tabtes Rorr\an Numerals Numeric Prefixes Triangle Formulas Plana Geometry Formula Solid Geometry Fomiula • Mining & Milling Sieve Sizes & Met Tables Stock Pile Volume a Weight Dumping Angles Mining Equipment Specs • Money & Currency Cutrency Exchange Rates Interest & NPV Tables • Plumbing & Pipe • Rope, Cable, & Chain • Steel & Metals • Survey & Mapping Percent Grade to Degrees Mappirig Scales & Areas Stadia/Apparent EKp Tables Magnetic becllnation • Tools Tap-Ole-Drill Sizes DnII A Cut Lubricants Fire Extinguishers Sand Paper & Abrasives Saw Blades • Water Water Friction Losses Water Discharge Tables Weld Electrode « Sokier Water Pollution * Hardness • Weights of Materials • Welding • 3200 Conversion Factors And MUCH) iiflUCH morej this isn't even 1/2 of ti|^^ct|iiM JjJBiiM Please send me 1 to 9 books = $9.95 each 10 to 24 books = $9.00 each 25 to 54 books = $8.50 each Nanne: copies of Pocket Ref \ Plus Shipping ^ ) Total Shipping & Handling per Order 1 book =$2.00 2 books = $4.00 3 books = $4,50 4 books = $5.00 5 books = $5.50 6 books =$6.00 7 books =$6.50 8 books =$7.00 9 books =$7.50 10 books =$8.00 11 books=$8.50 12 books =$9.00 13 books =$9.50 >14book3=$10.00 Address: City/State/Zip: Payment enclosed (mark one): Check Card #: Company: Phone:^ }. Money Order Exp.Date: Visa MasterCard Signature;. Colorado Residents add 4.7% sales tax onthebool< + ship- ping total. The Book Source, Dept 954, P.O.Box 620820, Littleton, CO 80162 TOLL FREE ORDER LINE!!! • (800)873-7157 CIRCLE 342 ON FREE INFORMATION C 6 HE-SHOPPER CIRCLE 342 ON FREE INFORMATION CARD WE HAVE AVAILABLE OVER 125,000 SURPLUS PLUG-IN WALL ADAPTERS THESE ARE ALL BRAND NEW IN A WIDE RANGE OF VOLTAGES AND CURRENTS IN BOTH AC AND DC OUTPUTS. WE ALSO HAVE 22O/240VAC ADAPTERS AND DUAL OUTPUT VOLTAGE POWER SUPPLIES. PHONE OR FAX US FOR OUR LATEST ADAPTER CATALOG OR CALL FOR AVAILABILITY AND PRICE QUOTE ON YOUR NEEDS. WB ARE ALSO INTERESTED IN PURCHASING YOUR EXCESS ADAPTER INVENTORY. CONTACT US TODAY! d^-L^f'l mU A^ r' 9VDC/500ma WALL ADAPTERS 2.1nimID/5inmOD plug • \o W > >\ Ul o o o N) • • \o W Ul Ul a ^< Ui o o o o o VG610 CR610 CSA APPROVED VERSION. SURPLUS TRADERS specializes in the distribution of surplus parts and equipment to the electronic, computer and hi-tech industry- We publish a wholesale surplus catalog which is available to the trade at no charge. Please maxe your request on your company letterhead or accompanied by your business card. If you indicate your areas of interest or specialization - we will key our computer to target special offers in your field of interest. Hobbyists and those not in the trade may obtain our catalog for a handling charge of $2. SURPLUS TRADERS P.O. Boa 27C Wiatvra Ua« Albars. V«raioiit 05440 514-739-9328 (Fax 514-345-8303) 12 RE-SHOPPER SUPtR SOFTWARE ! WE WILL TRY TO BEAT ANV PRICE ON ANVTHINC FROM ANYWHERE '11 A TRULY PROFESSIONAL STAFF WITH A COMMITMENT TO SERVICE •.'.< * /JfcR COUNTR * AWESOME 80286 TURBO -1 0/1 6MHz 51 2K inilillad - Full Silt Cai* 200 Wilt Powir Supply AMnJ BIOS ■ 101 Kiybunl Up to « MB on Mcthartiaanj t VO Siotm - 90287 Sodial R«Ht tmi Turbo Button K*ylDCt( (nd 3 LEDS CloctUCiiandar - . 1 VEAH W*HB*MTV Now HMHt. .^iSfffiSSSS? .. T 80386 20 MHz Power 1 MB - Inslalled - Expands lo B MS m Boanl - Z«o Wait Stala - Nonoo Laridmarii - 28 7-51oIs - I ■ JZBn.S- 16Qit. 1 '8Bil Msni Toww Casft - 200 Wan Powef SuppV ' ^ - Dow Bays 2-5-1«--1ffiH(»2-3l(r 80387 SocKei - CkKk Galendif 101 ■ Keyt>oa/d - 1 Year Wa^anf^ Fg«)f tBM Compatible. $995 AddS400ror 38&25 MHi IJPER SYSTEM 8088-1 -1 OMghz TURBO COMPUTER SYSTEM 1 -Drive IBM Compatible System with 256K Memory Sum* System Incbcte* £5«X Jf^TALLEDSOSai ProMSMf' VHa» Height. 360K,5 1/4 Ofwe INST ALL E D ■ Ou ai Speed —< 77 Mghi ai^ 1 OMghj—T URBO ' 6 itoU - 6087 Socket *lS0W3nPDwerSupp»y'D*l"teKeytoard'FulSiraCaMlof4-1/2m Drives ' 1 Vedf PansantUborWa^rartyD^fiase Unit (E)rWflWArr3nti&s Vary) AcW*20UeDfM \9Q Ad04»hfi[>f** ?4fi Ad(]i4CbS0rH* 2» ATiTColvUCin)vAMAJ&K0 SAk. AT4T 1?* BkKl^ 1 llVtwM Mono TtLkAJnCma Uono Gnphct Card fwfpTHilar pQiT ^nil Card w f van) C>r0 Plfj^wCli/aarTM Car] ^yy » WwiwyUpgiakBiSIW Avallabl* HARD DRIVE DEALS MINISCRIBE 8450 XT 40MB Hard Drive Kits 40MB - 1/2HT - 5 1/4" Frame 3 1/2" Drive-45MS Access Speed 8-Bit RLL Controller INCLUDED NiIN!SCRlBE-3085-85MB-MFM-3 l/4"-l/2HT $499 MMSCRIDE 3675-62MD-RLU5 1/4". NEW $299 MINISCRI QE-8450 ■ 40 MB ■ RLL-3 I /2"-NE W $23 9 SEAGATE-ST-138R-32MB-RLL-31/2" S199 NONl SCRIBE-a438 F-30MD- RLL-31/2"-NEW S179 SEAGATE-ST-23a-30MB-RLL-J UA'-iam $179 1 AKDON-TM-262-20MB-MFM-3 1/2" $149 W ESTERN DIG (T AL-MFM-XT Conl. w^ Cables J 49 RLL Controllera for XV ajid ATs Available CAIX! Limited Quantiiies 1 Year Warranty {rom Mmiscribc s^ PRINTER POWER ^¥.*o* IBM 5182 COLOR PRINTER BRAND NEW • H«BVy Duty • WkJa Cirrds* (133 C«)umn) ■200 CPS On«-1IOCTSConiBandiM Ltu $I,HS Pipf f flick Avifllbl* * SUAi f^HMiO P«p« ONLY |U.U EMy CIW4^ C«ttdg« RUoM ' JWfel^b 30 0«y WUTMH Q UAWnTT FHtCIHO — CA1.H II TOSHIBA P-321SL Iamazinc;! package Brand New 24-PIN-it6CI>S-72NLO-N»riow Caniag* Parallel and Serial Inler1ace-3ZK BuHer-Tracloi 1 Year Parts and Labof Package Includes P '.-I'.i i-' 12 UlrtCk Mull.sd.kt- H.Mmi II J h Oitl <- . ifiv'K Wsrra SAVE 72% Package Price Lst $399 MINISCRIBE WarTanty-6 Monlhs-NEW DRIVES Sc^ealo & Tandon Wananly-90 Days-OEM Pulls QUANTITY PRICING AVAILABLE CALL FOR details; '•:t- tlLSI MHlMlfeH VAtUt IN ink 'J^A' MP1 — PRINTMATE — 350 300 CPS ■ 60NLQ - Wide Carriage IB Wie Tctuioiiiey - IBM;Ej»on C«l«£ ' ViiiaUe vvf - IB kAwi Uwilkbwi Wlrnnlr i»».c— i-—.™—^ °"'' S 269 <:ttoini(7CDi(ni SEIKOSHA SL'SOAl 24Ptn-135CPS-54NLQ Below Dealer Cost BRAND HEW iPfcO" RITEMAN BY C-ITOH BRWWMEWf 120CPS-6OCPS Fj(p»nd«l $-t>1Q Narrow Carnage-Pairalei Intartaoe «p I H^ BO Day Warranty - CXlanli^ Priting Availacie MONITOR MANIA S. Cilrd Dc-ijl PRINCETON GRAPHICS Ultra Sync t4 Color Monitor M-MsjUteync- Ultra Hi Res 31 Dot Pilch — eoOiSOO R«urtie/wd Ml m CofltHt Ion — Fu« 1 • Y«ar Warrareif From Prlocaon WoftHof Cardi Only |^^JlQ IBM — VGA COLOR 1 3' Viflwmo Area 640i'WO - 31 Dot Pucti iaMMcicXll«7544(Sai BRAMONEW High P^rlQrmancfl Graphi:^ /^-^s/^^A 90 Day Worrany ( . - - - \ LislSi.&OS ONLY UNBEUEVABLE VALUE <3m> AMDEK 600T — Color 14- 'FIGe-Cotar-e0Oi200, QrMrVAirlMr Swilch, Tits Swnul BRAND NgW Usi M50 ONLY $209 AMSTRAD COLOR VGA .28 Dot Pilch Ullra-Hi-Res-1 2' VGA-PC-Model 12HR Tilt & Swivel -720)! 480- „ , Anli-Glare Screen Only 1 YEAR WARRANTY -BRAND NEW NCR - IS" - GREEN - TTL wiih NCR Monitor Card - 640x400 LIST $438 ONLY BRAND NEW 90 Day Warraniy $149 AT&T CRT-327 - 12" TTL-BI»ck It WhKe Monitor & ATAT 1024HP Card Hi-Resoltttion-«OCh4gO-rill & Swivel Works On All IBM ATiXTf A Compaiibiti W Day Wamuily QvuVitT (Wr»r ON LY 6-11 H,lMH».Z4-$ [Qi, Pro I4-CiiB LiitJI390 $119 AT&T 318H with AT&T Color Card Wi.tkM.n All lUM Al XI s \ ( ..m[«lihltv 12" - Super Hi-Res — CGA — Color Monitor 600x400 — .31 Dot Pitch — Anii-Glare Screen Tilt & Swivel - 90 Day Warranty CSrr!^ wiihlhe'AT&T VDC4d0Cotor"a[3~ Botroi Tn^n E^CiA Robotulon^ TnoSeiTQGARasoiiJl'On VouCaf' Buy Quantity Pricina: 3-J269, 6-^59. 12t2J9.Z4$£390J«24-Call ONLY Brand New Condition Factory Rcbuibished List $849 * * Electrified Discounters * (800) 678-8585 HC •iu4 drCEPIEOI Clislomef Servies i Tvclinicil Support (203)287-1976 30-DAY MONEY BACK GUARANTEE! FJI lhlur«) B< Kanow*"! Pr>cr an all htSjriuvni Frodwcti OtSei ikfjincv If f ' ^ »- >; r-w" rvt-T»-*if •« / RE-SHOPPER 1 If you mail to the computer marketplace . ... MAILING LISTS TO TARGET YOUR KEY PROSPECTS 1) HEATHKIT 2) NUTS & VOLTS 3) KENSINGTON MICROWARE Over 97,000 electronic hobbyists who purchase ham radios, home computers, educational courses. 83,000 Subscribers/buyers of parts and accessories for ham radios, computer hardware and software, CB gear, cable TV. An active file of 273,000 buyers and inquirers of micro computer peripherals. Select IBM- PC, Macintosh, Apple users. 4) JDR MICRODEVICES NEW! A large list of micro computer users. For details, call or FAX: J.F. Glaser Inc. 999 Main Street/ Suite 103 Glen Ellyn, IL 60137 708-469-2075 FAX: 708-790-5244 CMOS TLCS55 to.65 THIERS U C556 $0.89 AU0IOAMP5: TDAaW^ifiW) it.ii 0*0-220 CASE) TDA2030 (14W) $1.49 AUDfO POWER DRIVER ICs: NE640H $1.40 LM3eiN-S0....$t.29 ALPHA-NUMERIC LED ARRAY 7x5LE0Matrtx. For Moving Message Signs, Etc. By lEE. #2057-o/crow8. YourChotee: # 2058 - o/a rows. *OM aa WlthHook-Up (StZE:2X1.Sin) ** "**' 8 Fof $T7.95) R ARE SURPLUS FIND! NEWl RS232 DRIVERS 1488 $0.49 1489 $0,49 HAX232 $2.40 J FETS FOR HAMSl MPF102or2N5486 $0.40 Your Choice CRYSTALS $1,25 1.043 2.0OO 2.457 3.120 3.579 3.680 4.000 4.915 5.068 8.000 10.000 11.059 14.318 20.000 ALL IK MHZ liOS POWER FETS. ALL NEW! 1HF521 (TO-220)N-CH $0.S9 IRF531 (TO-220) N-CH $0.88 IRF 8531 (TO-220) P-CH $0.98 IRF243 (TO-3) N-CH $1.19 IRF 253 (TO-3) N-CH $1,49 VN67AB (TO -5) N-CH $0.79 VN10K (TO -92) N-CH $0.49 IRFD110 (DIP) N-CH $0.69 CAPS FOR HAMS I High VoHage I Very Dangerous. 110 MFD 450V AXIAL $1.99 800 MFD 450V CAN $3.95 6100 MFD 350V CAN $6.85 ALL NEW. NAME BRANDS I HARD TO FIND. CAPS FOR POWER SUPPLES 8200 MFD 50V....RADIAL,.. $0.99 12,000 MFD 75V,...CAN $2.95 21 ,500 MFD 40V.,..CAN $2.95 41 ,000 MFD 35V.,..CAN $3.95 47,000 MFD 25V....CAN $2.95 105,000 MFD 25V....CAN $2.95 STEPPER MOTOR $3.95 IBM Surplus. 8 wire. 4 windings. 7V @ 350 mA 1.8' (200 steps per rev.) DC. les. 20 ohm ea. 25 oz. in, torque. Works great on 5vclc. W/Data FOR ROBOTICS nUAC: BT13»>S001ZAW)1 SOO PRV. TO-220 $0.99 ay»S 8032 UtCROPROCESSOfl 80C32 By Matra. 40 pin DIP 1 2 MHZ. Very low power. $3,^ PLASTIC TRANSISTORS: 6 FOR 91 2N3904 PN2222 2N4124 2N3415 2N3906 2N4401 2N4403 2N4125 BY PASS CAPS ,1 MFD 50V RADIAL (.to in. spacing) 10/$1 (.30 in. spacing) DIP BJ%t CMOS EPROMS 27C32HQ (house #).$1 .49 27C84-2 (Intel) $2.9S( 7912 $0.49 27C256(TI) $3.50 27C512{Tl) $5.50 PN2907 2N356S 2N60e6 2N5551 2N5401 2N5172 2N6517 MPSAQ6 2N3417 2N50e9 2N33g2 MPSA56 STATIC RAMS 6116LP-15 $1.95 6264P-15,.. $2,95 62256LP-10 $8.95 2114 $0.39 7193-S45P $1.08 7805.. 7812.. 7815, 7824, 7906. ..$0,49 ..$0.49 ,,$0.43 ,.$0,49 ,.$0.49 7915.. 7924.. $0,49 $0.49 VOLT. REO. IC« LM317T $0.69 LM337T $0.69 78H12 $4.95 7eH05 $3.95 723 $0.49 tU84 $1.18 TL4^ $1.18 TL497 $1 .48 TO-3 POWER TRANSISTORS MJ2855....$0.98 2N4398....$1,49 2N3773„,.$1 .49 2N6547...,$2.49 2N3055....$0.e9 2N6056.,.,$1 ,49 2N6254....$1 .49 2N3771....$1.95 2N6038„..$1.95 2N 5881 ....$0.99 2N3772...,$1.95 2N6308....$2.49 2N 6879.... $0,99 ^.! I IONICS 11301 W.Saltllne Rd. #1 05 SG3624 $1,26 SG3526 $1.25 LAS6350.,.$1.49 LM309K $0,99 LM350K $3.95 FULL WAVE BRIDGES 1.5A 400V $0,49 2A 200V $0.49 IDA 400V $0.99 35A600V $2.95 XEROX LENS 4-etement, coated. F;5.7 lOhi. F.L. $9.95 fixed aperture of 1 .75 in. MPW TRUC DRIVERS MOC3010 MOC3040 MCIC3011 MOG3041|Q,gQ LINEARS OP07 (DIP) $1.49 T1062 (house*) $0.48 TL072 (DIP) $0.69 LM324(0IP) $0,49 LM358 (DIP) $0.49 LM348 (DIP) $0,69 MC4741 (DIP) $0,69 LM318 (DIP) $0.99 LF356 (can) $0.89 5532 (DIP) $0.99 5534 (DIP) $0.99 MC3403 (DIP) $0.49 TL084 (DIP) $0.99 HC4558 (DIP) $0.49 4136 (DIP) $0.69 LM339(DIP).. $0.49 75491 (DIP) $0.69 75492 (DIP) $0.69 ULN2003 (DIP) $0.69 LM3900(DIP) $0.59 LM2900(DIP) $0.79 XR2240(DIP) $0.99 — B^FSTsTSTRP— 3N: 1204 Your Chotoe: MPF131 $0.59 214-242-8702 FAX: 214-709-5041 TERMS: Send check, or use, Visa, MC. NO COD. USA.Canada Only. Add $3.85 Camrfton, Tk 75006 (Stofe prices vary) (or UPS, Texas add 8% sales tax. 90 Day limited warranty on all Hems. $15 min. 10 RE-SHDPPER QUALITY PARTS • DISCOUNT PRICES • FAST SHIPPING LED'S Special purchase on two types of rectangular LEDs. Both styles have a face which is 5 mm X 2.1 mm. Red LED 10 mm long and 4 mm wide at the base. CAT#RLED-5 10 for $1.00 200 for $15.00 • 1 000 for $50.00 g Green LED 8 mm long ar>d 2.1 mm wide throughout. _^ CAT#RLED-6 10 for $1.00 200 for $15.00 • 1000 for $50.00 T 3/4 (3 mm dia.) RED LEDS Axial leads CAT#LED-9 10 for $1.00- 200 for $15.00 > 1000 for $50.00 Cut and bent radial leads CAT#LED-10 10 for $1.00 200 for $1 5.00 • 1 000 for $50.00 ^ OPTO-ISOLATORS =C: Clairex* ClM-6000 LED-photoconductor isolator. Off resistance: 500 ohms. On re- sistance: 500K ohms. 2000 volt isolation. Fonward voltage: 2 Vdc. CAT* CLM-6000 $2.50 each • 10 for $22,00 Sigma#301T1-12B1. Signal apiplied to the input is coupled by meansof light to isolated photo conductive cell. High reliability switching. 12 Vdc. CAT#OP-301 $1.50 each REFLECTIVE OPTO SENSOR IR emitter and sensor pair pointing in the same direction. Light from emmiter bounc- es off object to be detected by sensor. TRW/Optron# OPB5447-2 Rectangular package with 28" color coded leads, CAT#0SR-4 2 for $1.00 CALL OR WRITE FOR OUR FREE 60 PAGE CATALOG WITH OVER 4000 PARTS! OUTSIDE THE U.S.A. PLEASE SEMD S2.00 POSTAGE FOR A CATALOG ONE MINUTE TIMER Originally used as a game timer this whits box with a blue button will drive you crazy. Box measures 3 1/4" square X 2" high. When the button is pressed 4 LEDs light and a beeper pulses. Every 15 seconds one led goes out and the speed of the beeping increases. At the end of 60 sec- onds the unit gives off a long beep fol- lowed by a low squelch, all LEDs shut off and the unit stops. If at any time during the cycle you want the unit to stop, press the blue button and the beeping stops and in ten seconds the unit shuts off. Unit re- quires a 9 volt transistor battery (not in- cluded) to operate. CAT# TMR^I $2.25 each • 1 for $20.00 9 volt Alkaline battery CAT#BAT-9 $1.70 each RELAYS 6 VOLT D.C. - D.P.D.T. Sigma# 70 HE22-6DC. 2 amp contacts. 52 ohm coil. Polycarbonate cover. 1 1/B" high X 9/10" X 3/4" CAT* RLy-62PC $2.50 each 24 Vdc- D.P.D.T. -PC MOUNT Fujitsu* FRL-264 D024/02GK y^^>^ 1 amp contacts. ~ '''' 685 ohm coil 1. 354" X. 858" XI, 110". Clear plastic case, "V' CAT#RLy-229 $2.50 each 24 Vdc - D.P.D.T. - PC MOUNT Omron# MX2P-OE-UZ-006004 492 ohm coil. Contacts rated 3 amps @ 120 Vac or 5 amps at 30 Vdc, Clear polycarbonate dustcover 1 .03" X 0.875" X 0.69". UL and CSA listed. CAT* RLY-230 $1 .75 each TOLL FREE PHONE ORDERS 1-800-826-5432 ABS INSTRUMENT ENCLOSURES Molded ABS Instrument enclosures are available in ivory, i)eige, grey, blue, and black. Front and rear panels in match- ing .090" thick ABS plastic or, as an op- tbn, anodized satin finish aluminum. Inte- gral P.C, board mounting standoffs and two sets of vertical mounting slots for front and rear subpanel P.C. boards. Includes 6-32 pan head screws and anti-skid rubber feet. All enclosures are 6" wide X 6.25" deep. Front and rear panels available in 2.25", 2.625-, and 3" heights. ivory 2 1/4" MB lA $7,50 6,50 6,00 beige " MB-2A grey MB-3A blue • MB-4A black MB-SA ivory 2 5/8"MB-1B $7.75 6.75 6.25 beige MB-2B blue " MB-4B black MB-5B ivory 3" MB-1C $8.00 7.00 6.50 beige MB-2C grey " MB-3C blue MB-4C black ■ MB-5C Satin finish aluminum front or rear panels, 1-* 104* 100+ $1.00 .85 ,70 $1.20 1.10 1.00 $1.40 1.25 1.10 2 1/4" PNL-1 2 S/8" PNL-2 3" PKL-3 NEON INDICATOR 120 VOLT Good looking neon indicator RATED: 120 voHs @ 1/3 watt. Mounts in 5/16" hole. Red lens with chrome ring. CAT#1ND-100 75c each 10 for $7,00 '100 for $65.00 MAIL ORDERS TO: ALL ELECTRONICS P.O. BOX 567 VAN NUYS.CA 91408 CIRCLE 341 ON FREE INFORMATION CARD RE-SHOPPER QUALITY PARTS • DISCOUNT PRICES • FAST SHIPPING MINIATURE GEAR MOTORS Buehler series 61.13 Miniature DC gearhead motors. Reversible. Motor and gearhead enclosed in rugged die-cast housing. 1 .55" X 1 .122" X 1.475". Long-life bronze bearings. 0.1 15" diameter flatted shaft. Two types available: 18 volts dc (nominal) @ 50 ma. 10 rpm @ 14 Vde (no load) 17 rpm @ 24 Vdc (no load) CAT#M0TG-18 $5.50 each 38 volts dc (nominal) @ 70 ma. 274 rpm @ 24 Vdc (no load) 451 rpm @ 38 Vdc (no load) CAT# MOTG-38 $5,50 each 12 VDC GEARHEAD MOTOR Soho# GBL 35-DH-21 080-1 OY Powerful little gearhead motor. 40 RPM @ 12 Vdc. 0.5 amps (no load). 32 RPM with load. Operates at lower voltages with reduced speed and torque. 6.3 pound inches torque. Stall: 27 pound inches. 3.1" long X 1 .375" diameter. Shaft: 0.1 S7" dia. X 0.75" long. CAT#M0TG-14 $11.50each 10 for $100.00 -fj^ STEPPING MOTORS Airp3x#C82711-M1 17 Vdc 23.25 ohm dual coil, permanent magnet stepper motor. 7.5 degrees per step, 2.25" dia. X .91" thick. 0.25" dia. shaft is 0,6" long. Two hole mounting flange, 2.625" centers. 6 wire leads. CAT# SMT-6 $6,00 each • 1 for $50,00 Airpax* 82710 12 Vdc, 36 ohm dual coil permanent mag- net stepper motor. 7.5 degrees per step, 2.25" dia. body X 0.93" high. Mounts on 2.675" centers. 6 wire leads. CAT# SMT-7 $7.00 each.* 1 for $65.00 POWER SUPPLIES 5 VOLT, 5 AMP Lambda# LUS-9A-5 Switching power supply. Input: 85-132 Vac 47-440Hz or 110-165 Vdc 37 watts Output: 5 Vdc ± 5% @ 5 amps. Overvoltage and overcurrent protection. 120 mV ripple. 5.2" X 3.8" X 1 ,375-. Grey, vented metal case. UL and CSA listed. CAT#PS-5S $14.00 each 12 VDC 2.1 AMP Lambdas LUS-9A-1 2 Fully enclosed switching power supply with screw terminal conn act tons. Input: 120 Vac 60 Hz, Output: 1 2 Vdc ± 5% @2.1 A overvoltage and overcurrent protection. Compact venti- lated case measures 5.24" X 3.81" X 1.38" overall. Includes instruction sheet. CAT#PS-122 $23.50 each 24 VOLT DC -2,4 AMP [s^ ^ _.-^ Power-One lnc.# HC24-2.4 Input: 11 5/230 Vac (wired for llSVac) Output: 24 Vdc @ 2.4 amp. Brand new open frame power supply with line and load regulatton, remote sensing, overload and short circuit protection. 5.62" X 4.87" X 2.50". CSA rated. CAT# PS-2424 $30. 00 each 6 or 10 mhz HU-18/U STYLE CRYSTALS - SPECIAL PRICE P 6mhzCAT#CRY-618S 10mhzCAT#CRY-1018S MINIMUM ORDMR 100 PIECES 100 of either VALUE $75.00 500 of either VALUE $300.00 1000 of either VALUE $500.00 CHOKE GRAB BAG 8 pieces, 2 each of 4 different tunable chokes. Actual values unknown. CAT# GRCK $1 .00 each ELECTROLUMINESCENT STR1P(GL0W STRIP) AND INVERTER Electroluminescent Strips used for back- lighting control panels or as decorative or emergency prime lighting source. They are thin, tough and flexible and operate on kiw current. They operate on AC voltage, and the preferred power source is a miniature DC to AC inverter. We received a supply of glow strips that have a bit of an odd shape. The strips are 2.15" wide X 5.88" long and are 0.035" thick. The luminescent area is 5.3" long X 1 .72" wide and has one corner cut off, leaving a useful area of fairly good proportions. We are selling the strips and inverters as a package. Inverter operates on 6 Vdc. Glow strip, inverter and hook-up diagram CAT#GS-500 $5.00 per set EXTRA INVERTERS Input: 6 Vdc Output: 225 Vac CAT# INV-1 $2.00 each DIGITAL CLOCK AND APPLIANCE TIMER Turn on lights, radio, VCR automatically. Digital clock and appliance timer removed from automatic electrto coffee makers due to design changes. Operates on 1 20 Vac and is cape^le of turning on appliances drawing up to 10 amps. Because of the application they ware designed for they automaticalty turn off after two hours. Guaranteed to work but some have surface blemishes. 4.2" X 2.45" X 1.1 "deep. Beige or ivory with brown trim. CAT# MCT $6.50 each TOLL FREE ORDER LINES 1-800-826-5432 FAX (818) 781-2653 • INFORMATION (818) 904-0524 Minimum Order $iO.0O- All Orders Can Be Charged To Visa. Mastercard Or Discovercard • Quantities Limited • California, Add Sales Tax • Shipping And Handling $3.50 For the 48 Continental United States - All Others Including Alaska, Hawaii. P.R. And Canada Must Pay Full Shipping • No C.O.D. • Prices Subject to change without notice. 8 RE-SHOPPER 13406 Saticoy Street North Hollywood, CA 91605-3475 CORP. (Call for free catalog J m. A,C. POWER SUPPLY STACO MODEL EIOIOVA This unit has been designed and con- structed for rigorous industrial, classroom or laboratory applications. These power supplies are brand new. Current frst price $7SO.OO. Specifications: Input: 120 VAC 50/60 HZ. Output: O-120 VAC 10 amps. In- cludes manual with schematics. Features! Ammeter^ voltmeter, convenience outlets power indicator and circuit breaker Dimen- sion: 10" xlS" x 6\ WeiRhU 22 lbs. Price: $1&5 TEKTRONIX MODEL 453 OSCILLOSCOPE Vertical, 2 Channels. Bandwidth and risetime: 10 mV/d(v to 20 mV/div; DC to 50 MHz, 7 ns. 10 mV/div; DC to 45 MHz, 7.8 ris. SmV/div: DC to 40MHz, 8.75 ns. Calibrated Deflection: 5 mVlolO V/divinll calibrated steps (1-2-5 sequence). Input RC: 1 megohm * 2%, 20 pf * 3%. Modes: Channel 1, Channel 2 (.normal orinverled), added alter- nate and chopped. Has vertical delay line. Honzonlah Time Base A: O.TusMivloS5/dtv in 24 steps. Length continuously variable from 4dfvto11.0 = 0.5 div. TTme Base B: 0.1 us/div to O.S sec/div in 21 calibrated steps (1-2-5 sequence). X 10 Magnifier: Increases sweep rate to 10 n se Wt. 27*4 lbs. Includes man- ual. Price: 5400.00 (818) 787-3334 HP 333A DISTORTION ANALYZER Covers 5 Hs: to bOO kHz range, Measurej down to 0.1% fullscale distortion, ^nciude^ auto nulling feature to speed up time con- suming portion of measurements. Also in- cludes swttchable high-pass filter to attenu- ate frequencies below components. Price: $69.'; .0(1 HEWLITT PACKARD MODEL 606A SIGNAL GENERATOR Signal Generator: Freq. 50kHz to 65 mHz in 6 bands = 1%. freq. call 100kHz and 1 mHz, RF output 0.1 uV to 3,0V at 50 ohms ± IdB over freq. range, output VWXR — 3D OBC leverage 0-10V, modulation to 100% + 0.SDB over freq. range- Internal: 400 Hzn000Hz±5%. External: DC to KHz. Power iiM»V, 50 to 10O0 Hz, 135 watts. Size: 20 W" (W) X -nW (H) X 14^'^" fU Wt. 46 lbs. Price: $250.00 L.R. TANK PERISCOPE Type M-24. Rugged military construc- tion. Contains two independent In- frared image con- verter tubes plus correction lenses, prisms, and eyepieces- The binocular view- ing system is directly connected to a prism- type periscope. The image tubes have dy- namic focus provided by a built-in adjusta- ble voltage divider. This unit requires 10 to 15 KV at Jcjw current for operation. Unable to supply power supply. (Dimensions: 18" high >t 9" wide x 4W thick. Weight 17 Ibs.l Stock #OP 9001 Price: $200.00 (800) 235-6222 OUTSfDE CALIF. HP 651A TEST OSCILLATOR Frequency range is 10 t-lz to 10 MHz in sk bands. Dial calibration,! to 10. Dial accuracy is ±2%, too Hz tol MHz, ±3%, ID Hz to TO MHz, Output of 2D0 mW (3,16 V input 50 n); 16 mW (3,16 V'-P"! 600 tl); 6.52 V open cir- cuit. Output monitor voltmeter monitors level at input of attenuator In volts or dB; accuracy is ±2% at full scale; frequency response is flat within in 2%, 100 Hz to T MHz; ±3%,10Hlto100Hz; 5:4%,4MHzto 10 MHz. Attenuation range is 90 dB in 10 dB steps; overall accuracy is sO.1 dB. Price: $295.00 HEWLETT PACKARD 8640B-OPT 323 SOLID STATE SIGNAL GENERATOR (w/o synchronizer) Frequency range: 450 KHi to 512 MHz, to 1100 Mhl with external frequency doubler option (not supplied). Ten Frequency bands in octave increments from 500 KHz; band 11 for doubler use. Ac- curacy: b digit LED read out. Stability: ■= 1000 ppm. Output power; -145dBmto +10 dBm (0.013 V to 2 V) into 50 tl. Level flatness is < -I 0.5 dB from 0.5 to 512 MHz. Imped- ance is 50 il. VSWR < 2.0 on 2 V and 1 V range < 1.3 on other ranges >. Spectral Purity: Harmonics at 1 V outpt > 35 dS be- low fundamental of 0.5 to 12B Mhz; > 30 dB below fundamental of 128 to 512 MHz. Mod- ulation: Internal AM, FM and PM, external AM, FM, and PM. Pulse frequency; 0.05 to 5 KHz. General: Power Requirements; 100, 120, 220, 240 V, 48 hz to 420 hz, 2 amps. Note: OPT 323 built to military specifica- tions. Ruggedized performance for better operation under severe environment. Size: 6" (H) X 19' (W) X 13V4" (D), Wt, 60 lbs. Includes ruggedized case and manual. Price: SISSO.OO Current Hewlett Packard Price $12,050.00 FAX (818) 787-4732 RE-SHOPPER 7 PRJCES Our competitive prices have placed us at the top. We have low, low prices because we mark down each item the lowest % we can afford. SERVICE For decades, our 23,000 customers have been satisfied because we are aggressive in mak- ing sure we do all we can to help cus- tomers save and grow. QUALITY We sell high qual- ity merchandise. If it wasn't good, we wouldn't buy it ourselves. Your satisfaction is guaranteed. SHIPPING We ship anywhere in the world within 24 hours from the date of your con- firmation. We can use: *Airmail *Airlines *DHL *UPS *other means of transport ©/^Q=Q= ^©^ /k ^^ ©/kl/kL© 1 -800-325-2264 DALBANl CORPORATION * 2733 CARRIER AVE " LOS ANGELES " CALIFORNIA * USA * TEL:213-727-00S4 ' FAX:21 3-727-6032 OR 213-888-6032 RE-SHOPPER Computers, Components, Tools And Supplies Computer Products 4025 Edwards Road Cincinnati, OH 45209 1 (800) 423-4499 Weller WTCPR Professional Soldering Station $99.99 Cyrix Fasmath coprocessor Fully compatible with Intel but much faster 80387-16 $299.99 80387-20 .....$349.99 80387-25 $429.99 80387-33 $529.99 Facit B3350 Wide Carriage Printer 18 pin, includes cable $329.99 MiniScribe M8450 Hard Drive Kit 42.6 megabytes - 46 ms access with 16 bit card, cables... .$249.99 db is one of the midwest's largest suppliers of electronic and computer parts!!! ICs, resistors, capacitors. Call or write for our free catalog. db Kit Systems - All the top quality parts necessary to assemble your own custom PC, AT, 386 or 486 system. 386-33 cache main board OK memory $1,399.99 14 RE-SHOPPER Microsoft Bus Mouse The real thing ...$39.99 EasyPrint shares printers for 2 PCs....... .$79.99 SQZ Plus from Symantec The best spreadsheet file utility for Lotus $49.99 EasyLan PC to PC Network Special Full resource sharing network with hardware, software, cables The whole works $179.99 Reference File, The first really serious pop-up database management system $49.99 Twin Advanced, Spreadsheet - Graphics - Data Management - This is the one that you've heard so much about..Ai3)^^ $49.99 -m^it^ %'• ^Lk ^^#%bt M tl .» 77 1.4« Vi (MI 4k.0>. nS(4 IS- IKfr! )»• noH IIT TJOfrsi ijr ms-n ur ran !jr tM«.» 304- n»SI SD4- t4H-) 4«r i400.» 4 or 1400-!! 4llir na-i s.KT IIS m lis 114 ») ISO IH uo IIS «0 4JS 30» i<» n» ant I.H 13.911 KM nx tlM urw or* n*d 11 iitil ra^ fn^Hiqr pnfKli bfovH of tlHJr riliriH smI iht. EIU/RFI flltfn ■» IH^ V ta tkt i4riirlin4H«'> fnfiHcy rHgt. TW nffix af Hdi ceri (if. -2 ir -i] h§Mn tlit hIx. - MflRimum O rcmg*; .25'lOMHi ilx — Moxi tnumQranga 3. 30 MHz. ilx - Moxirttum Q laft^: 20^ 20D MMz. MoJtimym O fongfl; [>C- B WHl- ^^Kimum Q farigfl DC- 1 MHz PvrT3*abiljFy (^|k 1 0. HI traniFtxnwr bvbw IdOhwIBn. PwmiolHli^ iiio]- 8.5. Rf IfaniFsrnwf 1o 10 irwMr). Piirnutnlllr (|u;-4.0. Ulnrndontm Hp.VHF. Pfoiw*,!!!, iia)-7S. DC. 40 Hi afn) EWI/SFI t.lwing. P(!«nwbi!ity lsKi]-75 DC. 60 Hi and EMI/RFI fg. ' Note Tafciai op^ifQIo qt 4 1:> IQO nfrtfci Ih^ tiowtd lf*qtfcncy ra.iga wihh t*ck.H:ftd O qrtd aFlicgiK-^ "Whftre the hard to find parts are found........ ond on hand" Calalog 6 included wiJhyour order (J3 a'la carl*]. 200 pcges, over 1 0.000 olectrCFnic PARTS includ- ing aimott any capaciPorflranarrilHnglomonDlylhic), r«ii£tor^ inducltx, wireorcablfl, h?roid^f#fril*. CotEini replacemeni part, anieftnaj conneckir {rf. compvtar, fC, «lKtricol|, tfiait, coiipilng. knob, motor, Iraniisi^^r. diode. EC. switch, raloy (^jid ilate tocontoctort], pro|Kl box, rubber feet, he res- wore [stainlojs, brasi, etc.). lubing, fan or blower, lube jfecelvin^ lo ifonjmllHng) or tube socicet. Pteo» add odeqyote shtpping (t3 ruin}. We accept VEja^ MC, Amexco, checks, COD odd $3. 13>5Jon«St. •Omaha, NabKoka 6B102 • 402-34&-47J0 • fax:346-2939 Surplus Sales of Nebraska 16 RE-SHOPPER BACK-UP ALARM ■ Prevents pwssible backing accidents ' Detects utiseen objects behind a vehicle ' Gives out a warning signal to the driver ' Eliminates the guesswork vifhen parking in reverse ' Never again will heavy rain, snow, or fog be a problem Easy installation onto the bumper Available in black, silver, chrome, red, ivory to match the color of your bumper ' 30 day satisfaction guarantee; Full refund if not satisfied $49.99 + K.iO ship(iin; £ Hindlin^ Send check or money order to: Calco International 18W0 Sherman Way Suite 51 1 Reseda, CA 91335 Tel: (818) 708-2334 Fax: (818) 708-2362 PENCIL-TYPE DtAM/ LOGIC TESTER. The Voltmaster 90S from Bel Merit Corporation provides a full range of digital-multi- meter and logic -test func- tions in an easily portable package. It hias a S/s-digit LCD with function annun- ciators and automatic po- larity indication. It offers automatic and manual range selection and data hold. Its functions include logic test, diode test, audi- ble continuity check by buzzer, AC/DC current measurement to 200 mA, AC/DC voltage measure- ment to 500 volts, and ohm measurement to 20 megohms. All ranges are protected. The Voltmaster 90S comes W\lh an operat- ing manual, two 1.5V bat- teries, power leads for logic tests, and test leads. CIRCLE 320 ON FREE INTORMATION CARD The Vo/fmasfer90S pen- cil-style DMt^ and logic tester costs $49.95 .—Bel Merit Corporation, 14775 Carmenita Road, Norwalk, CA 90650; Tel. 213-802-3666. Cable TV Descrambler Article Parts We stock the exact Parts for several articles published in Radio-Electronics magazine on building your own Cable TV Descrambler. February 1984 SB-3 Type 701 Parts Pkg $19.00 Includes all originat parts. 702 PC Board 7.95 Original 3X4 etched, drilled and Silk-Screen pc board. 704 AC Adaptor 7.95 12 to 18 Volt DC @ 200ma. 701, 702 & 704 29.00 All three for special saving. February 1 987 Tri-Mode 301 Parts Pkg 29.00 Includes all original parts. 302 PC Board 7.95 Original 5X8 etched, drilled and Silk-Screen pc board. 304 AC Adaptor 7.95 12 to 18 Volt DC @ 200ma. 301, 302 & 304 39.00 All three for special savings. Tri-Mode Tutorial. .7.95 26 pages of in-depth info. May 1990 Universal 901 Parts Pkg $49.00 Includes all original parts. 902 PC Board.... ....9.95 Original 4X7 etched, drilled and Silk-Screened pc board. 904 AC Adaptor 8.95 12 Volts AC @ 3 soma. 901, 902 & 904.. ...59.00 All three for special savings. CD22402E 12.95 Video sync IC (10 -9) Snooper Stopper.. .$39.00 Prevent Descrambler detection v/ith snooper stopper/data blocker and protect your privacy. Includes free article on Cable Snooping. Macrovlsion Kit.. .$29. 00 Macrovislon now you see it, now you don't with our macro-scrubber kit. Originally Published in Radio-Eiectronics Signal Eliminator (tunable notch tnter) $29.95 ELIMINATE a channel that you had unsuitable or CLEAR UP a channel that contains severe interference by eliminating it NOTE: If picture and sound are effected, this is interference and CAN BE removed. If only the picture is effected, this usually IS NOT interference and CANNOT be removed. Works on Cable or Broadcast TV. # 23H Tunes 50-66 Mhz & 6 Meter Ham , For channels 2 or 3.. # 46FM Tunes 66-108 Mhz; or any FM station. For channels 4, 5 or 6, # 71 3 Tunes 1 74-21 6 Mhz For channels 7, 8, 9, 1 0, 11 , 1 2 or 1 3. #1417 Tunes 120-144 Mhz For channels 14 (A), 15 (B), 16 (C) or 17 (D). # 1822 Tunes 144-174 Mhz For channels 18 (E), 19 (F), 20 {G}, 21 (H), 22 (I). 58 Channel Cable TV Converter with Intra-red remote $69.95 Re-Manufactured Jerrold 400 wltii new remote. Channel 3 output. Compatible with all External Descramblers. CALL TOLL FREE 1-800-332-3557 Outside USA Call 1-508-699-6935 Visa, MasterCard and COD. Free Catalog. Add $4.00 S&H, $6.50 Outside USA. D & D Electronics, Inc. PO Box 3310, VISA IVIC N. Attleboro, Ma. 02761 CIRCLE 340 ON FREE INFORMATION CARD RE-SHOPPER 1 5 SKCOND EPROM ERASER • A REVOLUTIONARY PRODUCT. • INCREDIBLE SPEED, ONLY 5 SECONDS. ■ ONCE YOU USE IT, YOU'LL LOVE FT. * SAVE YOUR TIME & MONEY. * A MUST ITEM FOR THOSE PEOPLE HAVE EVERYTHING. * DIMENSION: 7- X 4" X 3". • ONE YEAR WARRANTY (EXCEPT UV TUBE) reE-9088 $249.99 ELECTRONICS 12 3 A DIVISION OF MING E&P, INC. 1. Bcciustve Herns at good price. S, Unique Kerns at better price. 3. Popular Items at ttie best price. 1-800-669-4406 ORDER DESK ONLY DI61TAL VOICE RECORMR • ADM RECORDING SYSTEM. • INSTANT RECORD & PLAY BACK. • 4 MEGA BIT DRAM, PROVIDE YOU 2 MINUTES OF HIGH QUALITY VOICE. • 16 SELECTABLE PHRASE CHANNELS. • PlASnC HOUSING W/ MIC & AC ADAPTER • BUILT-IN 500MW AUDIO AMP & SPEAKER. • FULLY ASSEMBLED & TESTED. DVR-120 $189.99 RF REMOTE CONTROL SYSTEM 19683 digital coding 2 tiny tiatismitters ON/OFF confirming signal Dry contact relay output FCC approved SA-432 $49.99 DEXXA MOUSE Superior tactile feedback switch 50-750 adjustable dpi Opto-mecfianical design Microsoft mouse compatible UL and FCC approved DLX-MOUSE $39.99 ■Q ROM/SRAM DISK CARD For diskle^ PC station 1 «id DOS & files instantly Battery back-up for SRAM watch-dog timer rebooting RDC-512 (512 KB, 0KB) $179.99 RDC-1024 (1024 KB, 0KB) $199.99 HRDBTECrOR Very small size (2i"Xl.rX1.4") Advanced SMT design Extra high RFI immunity Adjustable pulse count feature Security industry quality RK-3000 $49.99 BARGAIN SALE SYNTAX Proto-typing PCB COMBO-1 $9.99 SYNTAX Proto-typing PCB COMBO-2 $11,99 SYNTAX Proto-typing PCB COMBO-3 S39.99 SYNTAX Proto-typing PCB COMBOS $11.99 SYNTAX Proto-typing PCB SUPER COMBO S69.99 1. Price are subject to change without notice. 2. VISA, MASTER CARD and COD(add S3) accepted, 3. Freight charge add $S UPS Ground, $8 UPS Blue, S15 UPS Red. 977 S. Meridian Ave., Alhambra, CA 91803 TEL: (818) 281-4065 FAX: (818) 576-8748 UntocJc th« muElvrlvK of the untversa. For inrormBtion cair (508) 832-6567 KRV CIRCDITS mSTEK IELlECm®KllC& -f( (THE S A SPECIALISTS) p- C508) 832-6567 DRIEF me 5A IC Bnd ^A2D are the mti%\ soprnsttcuLefJ anil relioEiie siflnd aiDne dcscramburs ever made for 5. a. equipment. Ttiey are hlgniy tnlegrattd prcmtjin deacramblArs designed to ~5. A. specincattons^ for superior perfDrmence. They heve no 'Jitters', no v^deo level proCilBms. no etlgnment ur quBIU^ conlrot prodlems. end no svnsltlvKu or aaslc design problemi assoclatad witn tits simple videii and clocK EIrcults of the SA-3 (THIS IS tIDT AN SA-3 CLONE OF ANY KINDI) The 5A10 and SA20 neve a greet looking csblnet enclosure, the quolltg at whlcD would Tit In beeutlf ullg with a coffiponenl home sterao/entertelnmenl sgstam. Also Lhe power supply Is bum Into tha enclosure. The 5A10 end SAZO ere evalleDle fremHAITlB lUCTSIMICI (THE s. A SPECIALISTS) WHO sail only 5. A, related equipment and only tlia belt e( tnat HAina ttlCTMMICI Ix dooiceted to customer satisfaction and Is ready to offer th«tr sarvlcea at comsetitive prices. HAITia tUtratniCI end (he SA10/SAZO ASSAULT DESCRAnsLERS ere reedy to blow away the competition. • Superior Perlormance " Conforms to S. A. Specs. ' Drop Field Capable (SA20) ■ Aulo Scramble Doled ■ False Firing SwiLcli IT D • High QuBiily Control • Handsome Enclosure ' Bum in Power Supply • Power On L.ED. 3 C Jl ■ CompeLlllve Pricing 18 RE-SHOPPER [n](aitgjn](al[ai(a](al(a]ta][nl(a|(nl(n!jnl(n]tnJta](a](BJ THE ELECTRONIC GOLDMINE MINIMUM ORDER: $10.00 plus $3.00 Shipping and Handling We accept MasterCard, Visa and Money Orders Call or send for our free catalog! P.O BOX 5408, Scottsdale, AZ 85261 PHONE ORDERS: (602) 451-7454 m (0] m i $1 BLOWOUT SALE Tremendous bargains on prime component only $1 ,00 per pack n 50 1% Prea'sion Resistors* qtos Plastic Transistor PC Leads atos Capadtors-Disc & EiectrolyBc* ■••'•■ Qtot OUS C&Us n-ma Solar Sefisore 2™ Tmy 1/8W RssistofS* ^l?i 1N40CM Diodes : °"J LEDs-[5ifferent Cotofs, Sizes* aill Circuit Board wilti Bubtile Readout Q D n D D n D a D D D a D D □ 20 30 2 2 40 10 12 4 20 20 20 20 10 20 10 10 071 2 0713 m Surface Mlg. Chip Capacilcxs*. -■.'■'. q-JJI Suffac© Mlg. Chip ResistofS* Silver Mica Capacitors* Micfo Red LEDs on Strip Tantalum Capadtor* 9V Mini Zeners 3MM Liltrabright Green LEDs Small Single Turn Trim Resistocs** ■ Oi'^-niM'^'nt^onn^r^ arx) wil cortin i^t mmxt v»fy«. Q716 •0717 •0718 •Q71S 0720 0721 Small diameter unjacketed fiber optic strand, Perfecl Iw lOOO's of applicaitions. Fun to ise and experiment wilh. C722 SFt ptac* lor 49* Each COLOR BURST CRYSTAL ^ MiniMuicCra. 3£?3S«MHi GB15 $1.00 Each 10 for $9.00 oiVti E: MAGIC SOUN SWITCH Trinen wiiti dtp ot lond. tint on kw mlljgg limps, mokid W>i StMiHlic OpHjiesoii J/DC. G65S $1.00 BLUE BUTTON TIMER, Unique game timer Iratutes4 LEDs that extinguish one at a time over a ONE minute period as the unit increases its beeping . Great timer for games. Operates from W battery (not incl.). C723 $3.9S BAG OF HEAT _ SHRINK ^ .^, Hindv isscrvntnt of 2Spa ol virious smshiociV [Q 31. ind .06* 1o ^'Oli. CI 79 $1.00 POPULAR ITEMS HIGH QUALIIY! 2 mil bags witti white block to wtHe on. Sold in packages oM 00 only. 2x3- ^0663 — 100^3.30 3 X 4 — G664 ~ 100/$3J5 3x5 G665 — 100/$4.00 4X6-— G666 — 100*5.50 9VDC ADAPTER Great Barga'ml Perfect tot almost all 9V battery powered items. Has 9V snap, tilteied output. For 120VAC. G724 $1.69 Sa\^^ INVERTER TRANSFORMER Srslt 4 [Bod Inr^ofmer tar uuwHh 55S K to mmwt I2VDC to 25W rw sliDtmlluDmcst! tubes wiEh sdwnilic. N1703 $2.00 Each 1,000 for $1,500 cPENCIL SOW SOLDER IRON PsfstbrMdinoairb'l:. Oc»iaIran12IMC HI 200 $2.95 4KV TRIGGER COIL For stn3tie tubs 4I~}— ^ JtufNITOO 1 .2B Each 1 ,000 Iw tCSO 1.4SEaelt 1.O0Ofar «700 COPPER CLAD PC BOARD , Diin liciblt PC mloiil cin be cltI witi s£rssor^ Do little sided A* k S*. G591 75# SPECIAL PC SOLDER PfflecsoJderliyour VJts. low freftifnj, ctcdle^tcondLjclnrily, micii) thin sol ilec sum 031 Da nwle byKKlec MtMl — BFlCol H1M9 ILbRoll n — ft .50 HORSESHOE STROBE TUBE StinlinJl-t/4'tall A1034 $3.75 w ELECTREC ICROPHONE SensIfnIypiJFtcitilg G703 69« STROBE TUBE A TRIGGER COIL ."^ Gm tsnta of mini inigM wnanbj tie i trigger col A1039 $1.75 LASER LIKE LED aOOIUICDtJIIiibrlliinldeer juml!ocaeiiill£Ds A1012 3 for $1.00 1,000 for $220 [g (0] IS @ (g (0] m tH (s] ta! #65 DRILL BITS rung IN caiDiiie. M(si piifiulir sin for PC tait&. G725 3 for $2.00 MICRO TOGGLE .^.S WITCH ^ SJWtffnnitii mounlins hiJitirat LI 806 $1.00 FLASHING RED LED r]]s^tstttw1 6VDC is tpplioj naliiinujatiaie. G301 79« 0ial(a]Jnltn](al[§(3[a](Hl(n](H][n](alJn][a][Sj(a]jn][n](a](n| GiRGLE 346 014 FREE INFORMATION CARD RE-SHOPPER 1 f f f 9if ▼"'* I us ! 11 *»• ELECTRONIC ROULETTE Numbers 1 thai 36, plus and 00 (38 LED's). Game board for "betting" included. Automatic shut-off. As much fun to assemble as it is to play. Easy-to-follow instructions. A hands-on introduction to high technology. BT-805 A game of chance, just like at all the casinos. No ball to lose, no wheels to spin. At the push of a button electronic sounds and flashing lights go off. . .and where they stop nobody knows. GRAND PIANO BT-802 A kit that teaches ^u the basics of electronics, and a miniature piano to ptay once you're done. Instructions as simple to follow as do-re-mi. A 47-note memory allows you to replay your tunes over and over. 15 notes spanning 3 octaves. Play your own originals. Or, set up to play your choice of 15 pre-programmed melodies. A hands-on introduction to high technology. OWI Incorporated 1160 Mahato Place Comptor. CA 90220 213,638.4732 FAX; 213.638.83'*7 STILL FRAHE TM PICTURE TELEPHOMC TRANCEIUER KIT Sends Slow Scan TU pici:ures over The Phone line in Twelve Seconds UCj^HTSC Video oiiti>ut ^u{ hoU as on c o ,-;-•■. : . DRAM, D-Reg . 9Zi..99 PC Board CBARE) $18 . S5 SBRes. Cap. Diode $28.75 fc*^-. .» ^\^^ 3iiKes.uap.»»ode »^» . f3 Hoduiai:on Cabinet Cuncu^> $12.75 Use J^ Power Pack ^^^ $ 8.75 ucl 1 ^ I TV Canera ^tfR $189.58 Hod. I TV I rtonitor j^^^ $118.75 Visa and FAX Order <213>827-1852 PHP" ££ecf^o:Qic:^ «K95.Box, 8901 r I ll.r {tlaxtifta Del Rc^, Ca. 30295 ALUMINUM RACK AND CHASSIS BOXES FEATURES: D8StC\ED FOR SHALL LOT PROBUCTtON EASY TO FABRICATE (ORtLL OR PUNCH HOLES} SHtPPBD UNASSKIHRLED (FLAT) ALL MAIM PANELS ARE FLAT FOR EASY FABRICATION FRONT AND REAR PANELS ARE CLEAR BRUSH ANODIZED TOP AND BOTTOM PANELS ARE BLACK BRUSH ANODIZED END PANELS ARE BLACK ANODIZED CHASSIS BOXES MODEl# WIDTH DEPTH HEIGHT MC-IA *' 3" 2" MC-2A 6- 3" 1" MC.3A g" 3- 2' MC-4A 4- 5' 3" MC-5A 6' S" 3- MO 6 A 8" 5' 3- MC-7A 4" 7" 4" MC-SA 6" 7' 4- MC-9A 8- 7- *■ RACK BOXES RE-SHOPPER CIRCLE 346 ON FREE INFORMATION CARD ORDER DIRECT FROM THE FACTORY ON PREPAID ORDERS SHIPPED UPS GROUND, SECOND DAY AIR $10.00 NEXT DAY AIR S20.00 CALL FOa LnMI'LliH: TjlTALOK AKIl HNCINI nmw; IIHIhNISIONS. \n ALiU STU(li CHASSIS rilNUlli^ AWIJIKS1AN1 LtllliHINK. CALL HOKCArALOC. SESCOM.INC. - 2100 WARD DR. HENDERSON NV. 89015 U.S.A. MODSL RU DEPTil PRICE 1RU5 t,75" 5" S 29.40 1RU7 t.75' 7" 31.50 IRUtO t.75- !0" 33.60 2RU5 3.S0* 5" 31.50 2RU7 3.50- 7" 33.60 JRUtO 3.50" 10" 35.70 3RUS 5.25" 5" 39.90 3RU7 S.2S' 7" 42.00 3RU10 5.25" 10" 44.10 800.634.3457 (ORDERS ONLYl • 702-565-3400 (TFfHMrAl IIFI P) • FAX 701-565 4US CIRCLE 345 ON FREE INFORMATION CARD Learn at home in y»ifr spare time Be an FCC LICENSED ELECTRONIC TECHNICIAN! Earn up to *■ $30 an hour ^ and more! GUARANTEED PASS.,. Here's our famous warranty that you will get your FCC License or your money will be refunded. You can earn more money if you get an FCC License Not satisfied with your present income? Add prestige and earning power to your electronics career by get- ting your FCC Government License. No costly school. No commuting to clas. The Origi- naJ Home-Study course prepares you for the "FCC Commercial Radio-telephone License". 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RE-SHOPPER : GRAY MATTER COMPUTING XT SYSTEM: 8088-10 with 640K, 360K Floppy, 2 parallel, 2 serial, 1 game port, 1 01 keyboard, clock/ calendar, monographic carxl & monitor. $399.00 AT SYSTEM: 286-12, 1MB RAM, 1.2 Floppy, 2 ser, 2 par, 1 game, 101 keyboard, 1:1 hd/fd Controller, monographic video card & monitor. $699.00 386-25/64K Cache system includes 2MB RAM, 1 .2 Floppy, 1 :1 hd/fd Controller, 2 ser, 1 par, 1 game port, 1 01 keyboard, 1 6 bit VGA Card & monitor. $2085.00 We wiff happily configure a system to fit your needs. WHY US Customer satisfaction is our primary goal. We know that you need knowledgeabie support as weli as prompt service. Here at Gray Matter, we take pride in providing these and more at a competitive price.And we enjoy it. That's why. 1:1 AT MFM HD/FDControiier $1 19.00 1:1 AT RLL Combo Controiier $130.00 XT MFM & RLL Controiiers $51 , $59 360K & 1.2MB Floppy Drives $60, $76 720K & 1 .44MB Floppy Drives $65, $78 CMS Jumbo Tape Backup $295.00 <^^' 4357 Mt. laaxiaiB Hard Drives: 40MB MR535 MFM 28ms RLL cert 72MB Maxtor XT1 085 FH 28ms 80MB HH1090 MFM 28ms 100MB CP3104 IDE (AT) with kit 200MB CP3204 IDE (AT) with kit $350.00 $625.00 $625.00 $695.00 $1070.00 ,,CA 92117 P-C-B ARTWORK MADE EASY I Create Printed Circuit Artwork on your IBiVI or Compatible * MENU DRIVEN * HELP SCREENS * ADVANCED FEATURES * EXTREMELY USER FRIENDLY * AUTO GROUND PLANES * 1X and 2X PRINTER ARTWORK * IX HP LaserJet ARTWORK • HP.and HI PLOTTER DRIVER optional 49.00 REQUIREMENTS: IBM PC or Compatible, 3S4KRAM DOS 3,0 or later. IBM compatible printers. PCBoards - layout prcDgram 99.00 PCRoute - auto-router 99.00 SuperCAD - schematic pgm. 99.00 DEMO PKC. - 10.00 Call or write for more information PCBoards 2110 14th Ave. South, Birmingham, AL 35205 (20S) 933-1122 PORTABLE DATA LOGGERS. A line of full- featured, rugged, data- gathering products that tie directly to thermocouples or voltage- or current-out- put devices has been intro- duced by MetraByte. The DDL-400 Series data log- gers, and the variety of available hardware and software accessories, al- low the user to configure a system to meet specific application requirements in tlie lab, factory, or field. The IBM-compatible, pro- grammable, menu-driven data loggers offer 16 ana- log input channels, fourdig- itat inputs, and 16 alarm outputs. A sealed-mem- brane keyboard on the front panel controls func- tions such as data-logging interval, Hi/Lo alarm limits, channel select/skip, and time/date settings. The LCD readout shows chan- nel data, alanm limits and status, time, and date. Each data logger re- quires a TCV-W I/O pane!, a slide-in module that has 16 single-ended inputs for thermocouple, voltage, or current signals as well as 1 6 logic-level alanm outputs and four digital input chan- nels for contact closures or logic levels. Each channel is independently config- ured by a 10-position range switch. Optional Applica- tions Software allows re- mote control of one or more data loggers. CIRCLE 321 ONFRiE INFORMATION CARD Every alarm in the sys- tem is independently and continuously checked at full speed at least every four seconds. Limit values are stored in non-volatile memory. continued on page 28 22 RE-SHOPPER RAINBOW KITS I THE STRIPPER ■ADA! SIGNAL DETECrot If you mink thai a sen- alt Ive radar dal actor la a tompllcatad place of equlpmaf>t» take a look at thia new kit. Ttils simple, yat affective, datactor circuit can be bulll In less than an frour and can tM tuned to respond to signala between 50MHz to SOOGHz. It's a fun kit to build and play witti. A clgaretfa lighter plug Is Included. Size yxW oparatas on 9 to 15vDC, KIT RSD-1 J12.95 SntOBE UGHT If you need an attention getter, or warning ligfit, you need tfie strobe light kit. Use It for emarQency light for eutos, for model plifias or radio towars. Evan use It on your bicy- cle. Operates on B or 12v DC and baa a variable •trobe rets. KITST-I $8.95 ncrrAL TBBIMox, set It on your dash and it looks like the real thing, ^ch kit con- tains two LEDsthal alter- nates flashing. Operates on a 9v battery. Size .5"k.S" KIT RB-2 $3.45 CAPAOTANCe METtA ' Tfits easy to build kit wlil turn your digital volt meter into a CAPACfTOR METER. Turn that junk box of unmarked capaci- tors Into a fortune. Meaa- urea capacitors from (ZpF to 2.2uF. Operates on a 9v battery. Size t.75"xl'' Kl r GA.2 $12.95 WIRELESS ra H1I£ Smell biit mighty .8''xV' PCS, will really stomp out a signal well over 400 yds. This is a buffered wireless mike thai oper- ates on 80 to 120 MHi FM. Comes complete with a microphone, and 9V battery connector. Operates on 6 to 1 2* DC. KITWM-1 $12.95 SURK mOOffiMIG EAB Use this BIQ EAR ampli- fier to listen ihrougb walls, hear conversa- tions across the room. Beef up Ihe sensitivity with a parabolic reflector and hear blocks away. Dim to the size, the BIG EAR can be bidden at>out anywhere. Use the ear- phones from a pocket transistor radio 10 liaten. Makes an ultra-sanslflvs Intercom. Can also be used as a general pur- pose 1.5W amp. We sup- ply a minl-mlcrophone in the kit. You can also use any B to 45 ohm speaker. Operates on 6 to 1 2v DC. Size 1"x1.75" KITAA-1 $10.95 AC UN£ MmiTDR This la something every computer user, photog- rapher, or anyone that must maintain a safe usable AC line voltage should have handy. Mon- itor the voltage of your motor home's llOv AC generator Inside the motor home. Every tech- nician's bench needs this Item. The AC Una monitor wlil Indlcete, with multi-color LEDs, what voltage Is being distributed to your equipment at that par- ticular outlet. KITLM-110 $10.95 U\ RATmtY MOKfTOR Have you ever been In your car, boat, or camper — you try to stirt your motor but the battery is dead? The SATTERY MONITOR kit uses the cigarette lighter plug outlet to monitor the true bdttery voltage. Multi- color LE[>s indicate the voltage In 1v steps from 11v to 15«, green means great, yellow ia good, and red — call the tow truck or get out the oera. Size 1.2"x1.75" KITLM-12 KM PHONE HIG Small but mighty, so small It fit a anywhere. Telephone Una powered, never needs baiteriea. Transmits both sides of a phone conversation loud and clear, wireless, to eny FM radio at great distances away. Variable tunes 7DMHZ to 130MKz. It can also be used to make any phone a speak- er phone, Size .55"k1". KITTEL-B1 $10.95 XXXXX RATED X WE HAVE THE BEST UfitT YOU CAN BUY AT ANY PRICE X AH. AUTOMATIC -NO CONTflOLS fJ.T 1 CABt.£ IN - 1 CABLE OUT ■,^1. X USEOfiANYVCH X THE ONLY UNIT WITH THf ENHANCINQ SWITCH X tD(n4 MONEY BACK GUARANTEE VIDEO STABILIZER PBONE RECORDING SWnCH This telephone line powers switch is small enough to install any- where only ,9"J(.6". Every time someone picks up the phone tfie tape recorder will record both sides of the conversa- tion automatically. Use it In your office to record all phone conversetlons so you don't loaa that im- portant address you wrote on the tiack of an envelope. KITTEL-SW1 $10,95 : If you rent movies you need THE STRIPPER \ When wMChfng rentat movEes you wEH noticft aflrtcylno pictura fb^hlng from tiark Lo \ UyM, color shifts, unwantsd linfla^ & pictura jUt«r». This ]> c«usesrMnL1'1utCdlF(»lwd- l irtg^ Oonfanndog; Plv>Mk Hflbry. Plui N uHfA vlmplQ I and (hdJ l^iorw ckciMt plant Morf 1 Mnuili $^ HIGH VOLTAGE DEVICES HV DSvl-CiB ' 5/UJi Gla; f^JSiT. Frod- Canff; ym(v.ffJtf; Zjipper flf/flidaf/j^Lfdjo J*iww*r; finthti. Ss»ttat: Jactib'x LadnsT, Piavns jm? i/an tf* G/affff c^ns ; FancQ Cftariof: GtitQ*/ Counr*/,- 0/ only], VISA Of^(J*l»^«C*^d OP. lOO- Mcntp I Computer and ilACCTCinic Olftn" FREE Tacti. CtMo^ I wfln ordw. T'JWK *nbuViniiM »*Kfl ig?1 A» W*fi Cifi TV ROeOFONE AUTODIALER to dial any number lup to 10,000) or mix ol local »rKl long distance ptiono numtxrrs a and conlrdi* Ml t*»iun codas, includ>ing VOICE and R1N4:^IM(j Optional shell lo tarmmaJ profltam ijpon COMiHECT EjiiI to Menu or 60S Hot tMlcbing]. IdDal a? k "Wi.rg»mei" dialer, phone call logge-r and iel«markelmd dialer Qttk* • Manual il^. WjIR LAIl£Ul and LETTEIt$ programs t49. Oplkvul ' ' ' eriaca t29S. HARD DRIVE MANUAL HBialn 10 wr rv/tl Drive and GOrttrOIW lomptuvi on PC/XT j'AT/MCt H(ml09*bacl>ntar1«ce, inFtiaiixe, Mt up., ine tfiern i^w ki mainiain, trouble' jjTrKUBfljMirihem Hffwto pfotocl them from mtHaket, sabotagm„ prying tryea, tbcky Fingara How to racovw ilarntseiCl arvd lost 1ile« Induce tAitcf\ rfilt k>und nowtwr« atie' tit. SAVE.1SS1 DISK SERVICE MANUAL Mwntain. tro^jwesriioot. repair, ad|U9i, a»ign Floppy Drives wittioul special equipment or sofewaie • 5r29''fXi''/t: PC/XT/AT/3t£, Appiu. CofmMtOttrw, Aajrp/D, TMnt/jf, eptwt, AtMfi, fi. HP. DEC, elc DtSK DRIVE rurORIAL ruedry, practical tacit on Floppy Driwt, Diwt, rDCt^ 1 Form^nin^, :^}lware PrOleCtiOn ror Ihe ty«t«ins de- scribeo aPov« invAltiaPle ndvice and lipt on how to I COMPUTER PHREAKING TROJAH KOnSES, VlnUScS, WORMS, etc, and CoujItvrMBUUrefft - irKludM Ditk' With 2S0K* ol prif eaKing lexl Mes and dish - prolectiH» prcnnuns.. and the graal FLU8HOT+ Disk'< {lEHUv'i Chc«ce. PC IMLAOAZFMEJ' Dozant oE CompuWr CrinU and Abu«a MeViodt, ar>d CouritatMeuures. How ayrtemrs are perteirvied. 6B5 Achicv: PWfword Dtteatt: 2oa PTiraah- Term Glouirv much more. 3 Itoiuali ■* 3 Dieka* S3JL KW-HR METERS I How (Hflctrkc energy metan worf, ciitDffndfi, rnany I trror modes, ANSI Standards Demat>d Melen, Pole I Meters, Polypha-w Meiers; meter cioe-p; overload I aroott. $JtL POOR MAN S SUPER LASER nupy Hod Liter Ptant Uted m iniruiior> sysiemt, waapon« tairgating, pjvcise opiical alHgrmsnEs, saismo- graptiy. argnating and commo, strobe), hdlograptiy, acianca projecis, ate rnciudes a lisi of dojenj oi em-rces lor ruby rod? and oihar pam il4. STOPPING POWER METERS A$ REPORTED OM CftS "AD UINUTES "1 How certain ete ci rical h»d« can ilow down Pqiw Uetert ^ even atofi tlh»m ^ whtt* drawHn^ tuH teadal Also desc^nbes Pok VMtn, H«t«f Cmp and I>wl9»d thooi^ (TS. BRAIN VIRUS ANTIDOTE The PAKI^TAHt WUIH VIRUS piaSUBd ddEi universities and busineues The mildly desir original vertidxt i* hack»d into highly virulani a BRAIH VIRUS ANTIDOTE consbtts of the antn ■AurcHCtHJeand wriia-uD DWt" fHOT kitocHMl . BEYOND VAN ECK PHREAKING mvasurea tncludettHalVvnE&ku^sft. Now includes iinal VAN ECK DC&IOW3I t2S, ATM Crinwi, Abuaw, SacurHy, VukwabiNliu tOi>* melhodi deacrlb«f - from Baa E lo ciphers C»e HAvWL Law. C01Frilarme*9Ur9f^d«M6d SfajMyChadt- \\ii Frttarrul PhototV Racontfy, a crook siole i33J.O0O THE I.G MANUAL LIBERATE GAS & WATER SURVIVAL GUNS & AMMO THE ULTIMATE SURVIVAL MANUAU Oeacrlbes optimum weapons and ammo to pick, conversidns of commonly available samtautos lo bh«uI1 weaports, silencers. expl£nivB device«. improviiad. End Times scenarios, ^etrfihats. elc JT9, VOICE DISGUISER Kians tor' nea.t device^ 10 cnange vDica 'rec^uenciH Etfactjva againsl snoops using vo»c:e analysers, to DOr^cevi gender lor woman hvir^g aiorve. lor elecbonic garT>*3jor inli'inlruBton sysiems, Iqr muticaFaccdtn- paniment; for seances, as a gag; as a dcKirbell subttitule; etc t19, Modulir 199- VORTEX GENERATOR I M«at/co«l wilh Simple, amazhrtg 3-Pd<1 Devic* Uses I no n>ovrrig pans. ete^tf»ciiy. lossi4 fuel, liquid or itton I Ouaranlwl Scienttfical ly Sound Plans t14. ROCKET S RED GLARE How to dest^n and build solMl-fuel rKkeU beyai^d modflH rocketry. Special etnphaaiaon the fdrmulitiori, manufaclure ar>d irisiallBlion ol prdpeJlanls. nvtitofs and igmlers And ihe design ol leur^ch pddt and electronics 919. ABSOLUTE SECURITY Dozens of wmple. versalile. secure CompiilSi' Socunly I meihodv. UpS. Plu$ ou/ invulnaraUa Cipher Program 1 {in COM incf ils BAS Source] Plus Sl.QOOl CIPHEH COMTEftT rulai wllh Ciphertexl f CRYPTANALVSIS TECH Litfl iSPOwaitulM4HVj^Drtv«nCiyptDPro{pima(in.COMarid m BAS SoyrceJ *o Aniiyife Oecrypi -Sftcufe" aphw- lextA. £jtamp(ei. Recommanded in Sie presltg^ous THE SILKWOOD I bmaii, aimpia (2-luj, efreci I higti voltage, heavy /special bsiiariH, or special I lubes Rivdieuori i& everywi^erc' Proiwct your heeJih' I Plana $14. THE GOLDFINGER Matal doTacior trnds GOLD, SILVER, PLATINUM, COPPER, ALUMINUM, Rejecli all Icrrojnagneiio dbjBCU Simple circurl Pitins $14. ■OLD f on [OUCAlrOHAL PUiUP-OStS Q««tY- STOCKPRO unKtufi, Kowerrui. :^rawd, UnconventiPrUl Cornrrton Slock Invntmeni Strategy. C^eatad for NMSU. Basis rtf nKn*n!tJiM(^nnsijllinnsvslam Manual '^Dlak* 129. PRINTER/PLOTTER MANUAL Types-. Uascripiions. 9P4Cb. and luU''' inieriaces (ParalMI, Sarial). Detailed Plans of X-Swiichert, Buffers, and Sana] -To - Parallel and Parallal-To-Semil Davicea. Many lervtcet repai{. buy, ita* tipe. <:7B, SUPER RE-INKING METHOD Re-Ink Cloth Rkbbor^E lor about SO cents and tO minules «ach Plans tor El Cheapo Moior^Ddven ^e- Inker. Commonty used inx (5 colors] and earner descri' ' ' ' ' SOFTWARE PROTECTION UnKfue syKteflt that highly discounffB coedy » piracy whil«nDlinlar1trlrigwi4^'kigirtardiPralcopws No I krvy^nrrvfthodofdeNANDspocvlecMpmerHreefuired. I Easy, autotfultd lo iftttaH Ck\ ba uatd with any other- 1 SPECIAL PROJECTS We [>B9^n, ^Md, Repair, Mod rV. Maintain arid CoTiUR on any Devicn, SyEMem or Project ^ Computenied. EJeclroniC- Electrical. Mechanical Opteel - many invention protdtypaa Cdnlidenlhallty guaranteed Describe erv) include f?$ non- refundable fee We than pfovwla you co*l^ time astirnaies TECH RESEARCH SERVICES UrVKiue 42K (lectronrc, computer d'Tsign anhclea m database acce^swl t>y tiiie, uibject DigilBk uP. uC analog, (rybnd. nomogriph. jaftware Provide us keys. weraturnlisiprig £23npn>reiundaDies<4rcMee1t-^ keywords/ phrn^^ ^vetydu R&D$SSl *&stiwafQ luppons PCD05, MSDOS, PS/2: Mo4io, Here , CGA, EGA, VGA; S 25"', 3 S". hard (specity your floppy drive sugj REMOVE ICS FASTER with this simple invention than any other method, including $6,000 vacuum desoldering stations. Salvages hundreds of good IC's per hour from junk boards, and also speeds up repairs. Won't damage IC's or circuit board. Removes 6 thru 40 pin IC's. This is a money making labor saving tool. Order novi». We pay shipping on prepaid orders. Complete set of 8 desoldering bits ^ 07 * 7 J LEARN THE SECRETS OF HOW TO FIX ELECTRONIC EQUIPMENT FASTER ON OUR REPAIR TECHNIQUES ON VIDEOTAPE Learn our techniques and make more money repairing electronic equipment. These tapes are packed v^ith much practical information that will save enough of your valuable time to quickly pajf for the tapes. Learn from an expert what fails, why it fails, how to find it faster, and how to fix it faster. Much of this information is available nowhere else. These tapes start at the beginning for beginners, but cover each subject JO thoroughly, that even old pros will learn valuable new techniques and skills. Send payment with order and we will pay shipping. Order all 14 tapes and send payment with order and get a 10% discount. (Send SS03.37 for all 14 tapes.) Order now. How to usea Voltmeter (I hr. SI min.) Sli.K How to use 1 logic probe and logic pulser SH.K All about resistors and their failure modes (I hr.) $39.!5 All about capacitors and their failure modes (I hr, 2B min.) $39.9S All ibout Inductors and their failure modes, Part I, Includes inductors, transforniiers, flybacks, pinhall coils, solenoids iW.K All about inductors and their failure modes. Part Z. Includes magnetic clutches, relays of all types, other devices. (58 min.) Slf .9 S All about diodes and their failure modes. IrKludes rectifiers. SCR's, Zenert, triats, LED's (SS min.) SJ9,9S All about transistor failure modes (54 min.) SJ9,9S How to solder like a pro — with lots of time saving circuit board repair techniques, including some of the fastest ways to cKange tCj you ever saw (I hr, 30 min.) , S39,M All about electrical contacts, connectors, connections their failure modes, common and uncommon problems, symptom:, good cures .... S39.9S How to use the oscilkiscope (to track down digital failures] S39.9S How to read schematics and use them for troubleshooting, Part I. Covers monitors, how to find monitor problems with wiring diagrams, gives symptoms, where to look, covers both raster scan and X-Y monitors (St min.) SJ9.95 How to troubleshoot digital integrated circuits — includes micro- processors, what goes wrong & how to find It, how to use the best literature on IC's and where to get it (I hr. 45 min.) , S39.?5 How to select and hire the best electraiilc technician. It takes one to know one, and believe ut they are not all created equally excellent This tape will save management and you a lot of grief if it keep* them from hiring a dud S39,9S VIDEO REPAIR P.O. BOX 813-RE SELMER.TN 38375 SCHOOL (601)287-1594 » RE-SHOPPER CIRCLE 351 ON FREE INFORMATION CAfID PRELCO 605 CKestnut St • TEL: 201-851-8600 Union, N, FAX: 201 J. 07083 -686-4656 2NS30e 2NS«3S SNJSM 2WSS9 2SM43 236171 2SB173 2SB178 23B17S 23B1M 238187 2SB1M ZSB4M SSBSIZ Z3BS«2 Z3B710 zsBest iSC63S 2SC7oe ZSC900 Tscaaa 2SCS30 2SCMS ZSCIOOO 2SC10S3 zscioe« Z3C13M 2SC197< ZSC181S 2SC1flS3 2SC1ft41 2SC19$g 2SC1S7S zsmosB zsciizo 2SCZ271 2SC2t«2 2SC3Cm 2SC32SeA JSD77 2SD«1 MDte7 ZSD200 2St}2ei 23[>*(n 2SDM0 25Dl1» 2SD12J7M 2SD1265 fSDIgeS SSD13S4 :SD1MI7 ?SD1*27 AN217 AN23« AhtMOP ANses AN277 AN27e AN302 AK305 AN318 mxo AN3W AN3313 AN3K1K ANS01SK AMGin ANS1G1 ANS31C *M57t» ANSTSO ANETSQ ANS7U ANS7M) 0.29 e.90 «.N 0.7S a.e« OAt LBS 0.3$ 0.3S 0/iO 04S O.SO O.SS 0.«0 0.40 0>0 0.»S 0.55 0>0 0.50 0.25 O.BS 0-20 O.W O.X O.IS 0.2S OM 0.5S 050 0.S5 O.X 0.f5 o.sa 0.S5, 0.V5 i.as 0.25 0.20 0.75 0.75 0.7S 1.2S 1,10 0.75 205 0.50 2.S5 1.50 0.50 0.80 0.75 1.10 0.«5 a.«o 0.70 1.55 1.75 1J0 Z.Cfi 1/W 1.7S 2.45 1.S0 3.50 3.50 3.75 1.00 1.55 2.00 3.50 iZS 1.50 175 3.75 4,76 1.50 1.76 1.50 1.flO 1.50 1.50 M«30» ANS307 ANs3aa MM3£7 MMOW ANt337 AN«341 ANS342 AN«343 ANe34« AN«3Sa AN83Ea AMseo AN«3ei ANe3e2 AN»368 AN«W7 ANT02S AK7V10 AN71n AN7115 AN7-142 AN7-t43 AN7143 AN7t4S AN720S AN7213 AN7222 AN7224 AN7310 AN7320 AN74ia AN7420 AN7S12F AN7815F AN7818 AN7SM()6 AN78M06F Ay-385-OO AV-sas-oi SA23S BA308 BA32a BAS21 BA5SS 8A532 BA612 eA71S SA72S aA1310 BA1320 BASSOS BA3Sia aA4210 BA4e32AL BA4234L BA44a2 BA44a3 SA456S BA5101 BASim BA511S BAei5 0.85 1.76 2.36 1.75 1.TO 1.90 3.10 2,76 1.96 1.95 2J0 3^80 CA3217e CA3218E CA3224E CA3234E CA323eE CA3237E CA3238E CA7e07E CA7811E C0224a2E CX770 CX20ai7 CX2303S CXA1019 0NeS38 DTAIM 0TA1MES DTC114E8 DTC114F DTC124E8 0TC144 0TC144E8 GH3F HA1139 HA1166 HA1187 HA133S HAiaet HA13e9R HA11227 HA11423 HA11714 HA11747 HAt20a3 HA12413 hU 17455 Hoxaao HDSOMI HDei40(2 IH240a lR2(ia insEoi iR2E02 IHC5 KA33V KA1222 KA21D1 KA2102A KA2130A KA220e KA2281 KA22e3 KA22ei KA2ei2 KA3213 klA7t37 KIA7S40 16930 LAUSO LA11S5 LA1201 LA 1210 LA1222 U1231 LA1245 LAI 280 LA138S LA3115 IA31H LA3ie0 LA3a01 LA3220 LA3301 LA3310 U33S0 LA^eo LA33ei LA4031 LA4ia2 LA42S1 1,76 ZM 5.96 8.9e 1.7S 1.76 1,95 1.96 8.M 3.76 8.1D 3.«i 4.90 1.75 0.59 0.90 046 HAS 0.69 O.H a69 1.95 2.99 1,39 1.80 590 2.70 2.70 1.50 E2S 5.50 7.60 1.26 1.50 0.90 5.70 3.76 7.90 IJO 1.60 i.50 1.60 O.M 1.56 1.50 0.5S 1.80 1.46 1.76 1.46 1^ 1.20 2.50 0.86 1,10 2,75 1.66 1.80 1.50 0,95 1,86 1,86 1.6S 1.76 1.80 D.8S 1.3S 1.2S 0.80 0.95 0.80 146 0,^ 1.75 1.76 1.25 2.20 2.50 2,76 1.90 £.96 LAU12 LA6621D LA7031 LA7032 LATOSO U7210 LA7e07 UT52a U7B30 LA79S0 UTBOO unx LA7«10 LB 1403 LB1406 LB14M LC4081B LH317T LM324N LM337UT LMaurr.e LH34OT4 LM34(yr-8 LM340T'12 LM340T.1S LM360T LM377N LM38CN LU3S4N LM65aCN LM1310N LH1S19N LM182ZN Ulil1823M LM18BBM LU1$77N9 LM1S80J LM18ft5N yil2877P Ly2901N LM8361 LM8690 LU11827B US218P H627SL68 U47O20 U61307BSP M64618P U688ieP U5ee2ef UAB8481P UBaioe UB8728 uBse3(» MBFUoas UBR3045 Mciaosp MC1361P MC1367P MC1394P MC3357P Mcraoecr MC78iaCT MC7SL15Ca MC79L18CO MC7SMD5CT MC78M09CT MC79W12CT 0,20 WJimtXT 0,30 MC7eMieCT 0,20 MC7S02CT 0J3Q MC79C6,2CT 0.3S MCTgOSCT 0.30 MC7«a8CT 0.30 MC7ai2CT 0.30 HC78U12CT 0,20 lilDA970-1 1.45 M:JE200 0.60 MJE340 0.90 HJEiaooT a.«a 1.26 1.25 1.10 1.90 6.20 2.00 2.65 1.60 2.76 2.76 3.75 2.25 2M 1.10 1.10 155 2.10 0.46 0,76 0,95 0,90 0.30 0.x 0,30 0.x 0,X 1,76 2,M 1,26 1.66 0,56 1.35 2:60 5.95 5,96 2,40 2,es 2,95 2,76 1,80 1.7S 3.10 3,10 3,00 0,90 0.60 2.45 6.26 1.x 2.95 2.95 £45 4.10 1.35 245 8.76 2.15 2.15 1.26 2.95 146 140 1.7S 0.x 0.x 0.26 0.26 0.20 0.20 MU&3S8N MM5387 MU6402N HM546W MM7317BN MN12«on MM183A MW168 MN8178 MN158S3 MP19D9 MPC674J MPSA13 HPSUlO MRf421C MRFMAC MFV:841 MW=644 MHF901 MRF91t MSL218 MSL9372 MSM6S26 MUR30a5 MUftX15 PKnz RC555N SAB3038 SAe3037 SAF1039P 3109794 STA401A STK011 ST1C4S3 STK4 19211 STX5372 STKM71 STK6479 8TR380 STTOSIA STFU61 STH2013 STO3115 STB312S STR313S STn30123 STB301X TA7117P TA7137P TA7142P TA71S7P TA7160P TA7223P TA7230P TA7297P TA732SP TA7330P TA7331P TA7335P TA7342P TA7343P TA7353P TA736aP TA7378P TA7907P TATeilP TA7«13P TA7914P TA782SP TA7e30P TA7840P TA7644P TA796eP TA78e8AP TATSTOP TA7878P TATeeOP TA7887AP TA77T7N TAtllOP T1A810AS TBAnOM 3.00 1J9 046 1,60 1.W 246 3.16 3.78 240 3.76 340 1.56 0J6 0,65 13^ 8.80 12.76 7.96 1.10 1.26 2.78 3.76 2.76 1.72 1.72 0,X 0.16 3.75 2.06 1.x 0.75 2.60 445 6.20 11.60 6.x 5.10 6.10 4.76 4.7B 6.25 6.x 4.75 4.75 4.75 4.76 4.75 2.70 1.10 245 1J0 2.10 146 1.75 2.26 1.25 2.55 1.x 0.00 1^ 1.86 140 1.25 1,» 1.85 1,86 2.x 2.55 1.76 1.76 1,60 6.76 1,75 1.x 6,75 4.10 4,76 2J0 5.76 1.75 13S 0.96 2.20 1.60 1.60 1.7B 2.76 IJO 1JS X30 240 2.10 246 0,96 1.26 1.66 1.66 2.86 1.60 1.66 2Jia 9.10 4.20 TCS14EP TCAS30 TCASUSM TGMSOO TCP4e21 ■n)«2ioeP 7DA1067 TDA10«3 TDAIITO TCiAllBOZ TDA1220A TDAISTSA TDASJxraV 'rDA20O8V TDA2577 'n)A2K0M 'n)A2S22U T0A3iga TDA3664M TDA3670 TDA3963CQU 3.86 TOM505A 8.76 "n.7S3C TLP690Q TMC1073 TMS1026 T1ilS1046 TMS1071 TM31761 TUS19U TMS1962 ™S3460 TMS3461 TMS3462 TMS3496 THC2073O U419B WITB UA7S7 ULN21iaA ULN2212 ULN2218 ULN2224 ULN229 ULN22Z0 ULN2291A ULN2290e ULN38iaA ULN385e UPA53C UPASOC UPC27C UPC35eC UPC3a3C UPC654C UPC671H UPC674 UPC676C UPCM6 UPCS87C UPC592H UPC1018C UPG1029 UPCIOISM UPC1197C UPC1204C UPC1213C UPC12S3C UPC1360C UPC13S2C UPC1383C UPC1J71C UPC1S73H UPC137SH UPC13(7flC 1.36 1.50 340 4.96 6.80 4.50 245 2.M £M 2.M 24S 246 246 1.60 3.10 2.x 2.76 1,76 145 245 1.x 1.06 1.x 1,85 2.10 1.x 1.95 146 IJO 1.x 225 ^M IlK IJO 1.20 1J0 1.26 445 1.26 4,10 2.76 1.26 1.76 146 1.66 2.60 1.25 1.36 240 2«5 2J0 toa 140 1.80 UPC1382C UPC1X1 UPC 1470 UPC 1473 UPC1613 UPC16U UPC1620C upa29i UPD2az UPDftiOC UPD048 UPO1200 UP012r»C UP01704C upoiToe UP01937C UP01»43Q UPDi98ec UP01997C uptwwr uPMoera UPH091 UPD46«e8 UPO8104C upoem UP0753eC UP076109 X0137 121-I85 121.1014 121-1028 121.1035 121-1M7 14DN158 14DN197 14DN209 14DN233 15.3X59 1M7701 IMTTOe 15.37704 15JW207 15.39209 15-39208 1W1927 1541784 15430M 1543703 16-46300 221-42 221-43 221-4501 221-48 221-«i 22177 221-79 221-7»01 221-S7-01 221-02 22147 221.07,01 22147-Oe 221-10241 221-104 221-106 221-109 221-111-01 S!1-140 KM 57-02 221-16»«3 221-19001 221-194 221-175 221-177 221-178 221-179 221-190 1.70 140 1.10 1.111 1.35 1.x 2.76 2.95 2.96 3.95 5.66 8.95 2X10 2J» 6.x 2.10 2.60 1.96 1.86 046 0,36 046 0,60 2.10 846 4.96 646 3.06 045 0.x 0.70 0.70 0.75 S.X 9.M 6.76 6.10 1.25 2.05 1JS 1.76 4,95 2.2S 2.x 2.20 4.10 440 1.35 l.X 1.70 2J1S 2.x 1,76 1.99 320 2JS 1.75 2.15 0.95 1.75 1.76 1.76 2.86 1.06 2.10 2^ 0.76 3.76 1.86 1JS 2.15 2.78 6j05 1.K ^M t.96 5.96 221-192 221-193 221-213 mi -261 221-2S7 221-286-02 221-286-03 221-291 221-303 221-304 221-343 221-M7 22141S ^1419 221-493 221-619 221-628 221.646 442-58 442« 442-74 66D3-1 6809-1 690^-1 68024-1 55026 673319-10 8101424 910410-2 910442-1 810458-2 610457-2 810471-1 510651-1 812024-1 812042-2 912044-1 912090-1 912070-1 912072-1 9120794 912079-7 912094 912106 912120-1 912208-1 912306.1 812331-2 812337-3 812337-5 «1233»'3 ei 23474 912361-1 912405-1 912442-1 912446-1 912479-3 912480-1 DU32 DU5a OMSe DM109 DM112 DMie3 DS1D2 10-13 IC-27 10-32 PC00OO49 PCOOOOGO PC000061 PCOOOOOS pcoooon PC2M18 PC20919 PC20923 1^6 2.10 O.X 9.10 9.06 6.x 6.x 1.06 340 1.90 0,76 2.80 8.96 1.80 440 8.76 2.x 2.76 2.35 1.05 1.98 1.16 1.x 1,10 1.x 1.06 1.96 0.26 0.25 D.n 0J6 O.X 0.70 0.75 2.20 2.76 l.X 2.36 IJO 1.06 2JS 2.85 2,15 6.10 3J0 3.10 1 JO 5,X 4,70 4.70 6.10 1.06 1,10 225 4.9$ £95 0.75 1.65 1.10 1.20 0.75 0.18 0.76 0.76 0.19 £36 £10 240 6.M 9.20 9,20 5.86 5.x 2JS 8.00 9.x Our Policy: ■ Mininuni Oidtr 12600 ■ Al Pi/ti FidiHy Prim • W* Acoiipt HC/V)h - ALOniKi Slini^ Vl> UPS Qmvnd ■ PIhh Add tSOO^MuiAg On All Ontn • NJ. O w M tn tt PlwfMd «W3<)H Tu > No CaO.'t RE-SHOPPER 3 NEW AFFORDABLE - PRECISION TEST EQUIPMENT E.T. Tech., Inc. - Pivision of Empire Telecommunication Inc. I' ^ SIGNAL SYNTHESIZERS I SYNTHESIZER PULSE GENERATOR PGS-33 $1355 .100000 Hz, - PGS-33 ^ '*^^- Provides digital pulse train synttiesis witti six digit resolution. Cortrol of single and dual pulse delay and duration. Multi-modes in- cluding burst pulse train and variable duty cyle. Output to 20 Vp-p with 50 ohm im- pedance. D.C. offset witti TTL. SG-100 $685 .1000000 Hz. - SG-100 ^^-^^^^ ^^'- Six Digit resolution, .005% accuracy low distortion sine wave, output and adjustable to 20 Vp-p with 50 ohm output impedance and TTL. GPIB Option. SG-102 - $955 - Dual signal independent out- put or phase locked to one of 16 phases. SYNTHESIZER FUNCTION GENERATOR CLOCK SIGNAL SYNTHESIZER ; 1 SFG-33 $1275 ,100000 Hz. ■ SFG-330 32.9999 MHz. Wavelbrnns are provided with six digit resolution, ,005% crystal accuracy. Waveforms are sine, triangle, square, and rising and falling ramps, with dc offset and 20 Vp-p 50 ohm output over 80 dB range and TTL. SFG-330 - $17B9 - Keyboard and GPIB entry dBv and recall features. Options: 66 MHz. and dual Quad output. CSS-33 $1095 100000 Hi. ■ 65.9999 MHz. CSS-33 Clock signals have six digit frequency resolution, cryystal stability and .006% accu- racy. Squarewave output .002 to 20.0 Vp-p v^ith 50 ohm output impedance and TTL, DUAL SIGNAL & PHASE SYNTHESIS SG-112 $1350 99.999 KHz. Dual signal low distortion digital syn- thesis. Independent or locked signals. Locked signal phase resolution to .01 degrees. PM-100 $855 Measures test signal phase to .01 degrees as compared to reference from 10 Hz. to 2 MHz. SIGNAL DIGITIZER & SCOPE MEMORY WAVEFORM GENERATOR SD-200 $795 Signal digitizer captures signal transient for scope display. Adjustable sampling with 200 nsec. maximum, stores 8 Kilo-byte with 5% amplitude resolution. Pretrigger display enables analog scope to operate as a storage scope. SD-240 $1395 Waveform Generator captures signals and allows for signal data entry with a iigtit pen. E.T.TccK,inc To order or for more information call or write: 125 South Van Brunt Street, Englewood, N.j. 07631 Phone 201 569-3339 Fax 201 569-5838 Nffwlnl5lliflenMveragir.gAlgoriErim Pf[>DJam5&4AmtGi5ed.,?S6Jrttmin.,1 Meg(27D10rQl1}ini2m]r[.45&K, 2 Mefl (27C200i) m 5 rflifi IrttemaJ card wiih i7.\^ttM\ AO pm ZJf , RAflds, verijies, ztnct prog rams 2716. 52, 32A, 64, 64A. 128. laSA, 256, 512, 513, OTO, OH , 301 , 27C20(>t.MCM&a764,2532 AntomMtfafty ati p^fMmming voitMyt Lctfd a^d save birrter to disk Smiy, tnttl Hex, and Mslorofca S Normals Up§rwtl*bt9 to 22 Htg £PflOM$ He pafsoitality modules rat^ulnd 1 year wzrr^nty < 1 day money Dack {FuaranTeiC Adaplftns available (or 8743. 49, 51 . 761 , 52. 55, TMS 7742, 27210, 57C;02.4, iJid memory Urds MadeinU.SA 2 ft. Cabl« 40plnZlF NEEDHAM'S ELECTRONICS 4535 Orange Gn>ve Ave. * SiCf ameiiio. CA 9584 1 ^^ ^ Mon. -Fri 8am'5pmPST C.O.D. Call for more inform ation (916)924-8037 ■ F=AX 1916) 97Z-996Q 26 RE-SHOPPER CIRCLE 339 ON FREE INFORMATION CARD NUDE! ▼ NUDE! V NUDE1 "NAKED" WORKSTATION CASE & POWER SUPPLY At the scandalously low price of only $59.95 for both! •S* It's brand new... it just isn't wearing a plastic front panel, bezel, key switch or LEDs. Featuring: ■ 230 watt 110/120 power supply (AT style, back switch)! ■ Eight (8) V^-hcight slots for drives (6 front, 2 back) ■ Accepts eight (8)-s!ot mother board (full or baby) ■ Extra 12-volt cooling fan ■ Speaker for mother board ■ SL\ (6) rail sets included ...With ait this, it's worth twice the price! And more bargains... SWITCHING POWER SUPPLY Only $9.95! Fully enclosed with switch and D.I.N, power connector. ■ 5v at 4,5 amps ■ -12v at .3 amps ■ 12v at 1.4 amps ■ +12v at 1.2 amps Electronic Parts Outlet • 2815 Fondren • Houston, TX. 77063 (713) 784-0140 • FAX: (713) 784-9740 Wee locations in Texas..,.Come visit our retail stores! ELENCO ELENCO HITACHI OSCILLOSCOPES B+K PRECISION HITACHI Model V-212 20MHz Dual Trace IM $399 other Models Model MO-1251 20 MHz Dual Trace Compontent Tester Model 2120 20MHz Dual Trace V-522 - SOMHI. DT V-S23 - SOUhz, DT, Delayed Sweep V-S2S - SOMHi. DT ] V-660 - eoHz, DT $355 $389 V-6S5 - 60MHJ, DT, w/cursor V-1060 - 100MHz, DT I V-1065 - 1O0MH/, DT, w/cursor V-1085 - 100MHz, QT. w/cjrsor V-110dA- 100MHz, QT V-11 SO - 1 SOMHI. QT MO-1252 ■ 35-50MHZ, Dual Trace, Oslaysd Trigger _$475 Digital Storage Scopes P-1 Scope Prob« - 65MHz, XI XI $13.95 p.2 Scope Probe ■ lOOMHz. XI XI $22.95 212S - 20MHz, DT, Delayed Swasp, Compon- tent Tester ^$479 1541 -40MHz, DT $650 2160 -60MHz,DT,D8layed Sweep $899 VC-6023 ■ VC-6024 ■ VC-602S ■ VC-B045 ■ VC-6145 ■ 20MHz, 20MS/S 50MHz, 20MS/S __ SOMHz, 20MS/3 100MHz, 40MS/S_ 100MHz, 100MS/S _$84S _S930 _S975 _S 1,050 _S 1,290 $1,370 $1.6S0 51,950 $2,200 _$2,67S _$ 1,695 $1,950 $2,195 S2,885 $4,595 All scQpes Include probes, schematics, operators manual, and 3 yearwanranty on parts & labor. Many accessories available for all scopes. Call or write for coniplete sp«cJfica!ions on these and many other fine oscillosoopes. ELENCO TEST EQUIPMENT Digital Triple Power Supply XP-765 $245 Fully regulated. Short circuit protsctsd *fth 2 cuirenl limit controls, 3 sajiafalB supplies XP-660 With Analog Meters $175 GF- 8016 Fun ction Generator ^wttt) Freq. Counter $245 Sine, S<)uara, Triangle Pulse, Ramp, .210 2MKz Freq Countif .1 - lOMHi S^ J GF-801S wlltiout Freq. Meter $179 flSBH Multimeter wift\ Copacrtance and T(onji$tor Tester $49 CM-1500A Reads Volts. Ohms Current, Capacitor, Transistors and Diodas / with case Digital Copocrlance .^ . Meter CM-1550 $55 9 Ranges .1pf-20,l»(Iufd .5% basic accy Zero dr w/ case Quad Power Supply $55 2-20V @ 2A 12V @1A 5V@3A -5V @ .EA Fuity regulated and slwrl circuit prelected Wide Band Signal Generators jSG-9000 $125 RF FrKi 100K-<50MHz AM Modulation of 1 KHz Variable RF output SG-9S00 wllti Digital Display ind 1 SOMHz tjullt-ln Freq Cir $24S Digital LCR Meter LC-1801 $120 Measurfls: Coil* 1UH.200H Caps .1pt-20Dut __ Res .01-20H eaee Digital Multimeter ^^ M-IDOO $24.95 19 Ranges DCV-tOOO ACV-750 DCA-10A Res-2Ma Diode chedi Triple Power Supply XP-620 Assembled $60 Kit $40 2t0tSV91A, -2to-15V@1A (or 4 to 30V @t A] and 5V @ 3A Contains all the desired leatures tor doing eiperimsnts. Features slion circuit pfotedlon, all supplies Four- Function Frequency Counters F-IOO 120MH $175 F-1000 1.ZGH $255 Frequency, Period, Totalize, SeK Ctieck witli High Stabilized CryslaJ Oven Osoillator. 8 digK lED display 10 Function Multimeter CM-365 $59.95 AC + 0C Voltage 1 Amps Resistant^ to 2000Mn Diode, Logic, i Trans lest Capadtanca to 200uF Frequency Counter AM/FM Radio Kit AM/FM 108 $24.95 Manual teaches AM i FM Theory In easy to unde island language Many more kits available OMNITRON .dAve. BIDR 7-?A . NJ 07642 . ' UPS Shipping: Continental USA 5% (MAX FRT S20> Money Otder, Ctiecks Accepted Sctiool Puictiose Orders NET 30 Sorry no CODs Aad 5% !or credit card too Poge ColQlog S3 CFRSE wiMi ordf " 201-703-9800 201-703-9804 (FAX) DIGITAL METERS NEW DMM 2360 129.95 DSIM + LCR Meter Most Versatile DMM • Inductance: 1nH-40H • Capacitance: 1 pF - 40 nF • Temperature: 40 ■ 302°F • Frequency: 1 Hz • 4MHz • Logic test: 20MKz • Diode test • Continuity beeper • Vott, current, ohm • 3999 count display • Peak hoid • Auto power off DMM 135 $79.95 MEASUEE T^SPEXATOHE • 0<'.1400°F -ac-Tsox .r.l" resolu- tion • C:1pF-20nF • ,in-2oooMn • Voil, current, continuity '* Diode, hFE tests • Type K ther- mocopuc>(i«teH9iiMH tiJLtn ZJSOK HmdHidlJDMtEHMHI tUD ZiZ)M HndtaMlJOgltaMMWiM Ssio tnw MnUnJvanilCaudtir Kloa jn?A Fl»g.RV,Pt»niSi«jlf teilW Vi» TiJFdiOutxJtDC&ffily t»iU ltt7 DKKliRwliinetBn 49J0 3)20 SamiomduckirCliKiw MJO CtUA L«erT(airw,Wr*l XSM «a>K Itmliiiai.n ■ \iiJ10 «9S DuWTrK«»HH[OKiladLcn:PUMt aO.CC M7A HmM Pukird CtirMTrica 37e(C 54«A HwMPadiatdlogisC^ 192.CO w:ZA AI4inC«rrCia> tlfcCO SP100 Satid-PaiM CawM*. 1 10VAC fS.OO "Esm WBIZ Ni]t*:T>wvn44Mtcfwnp0Mnlpar1tusu4fy9U{:i^«d wih nvBw^ H* net aviMUa ■ ^ ' 314aA E4S(yi ECItOt EE10M Ecesoi EElOt eEio2 EE103 EE104 EEioe EE110 EEJJOtA EEBoea CoKcpto o{ Bvctonk* Covi* Flw l^ica Uarmg Count Piws Cirail DHi^i Con* DbU OicuI Mgn CocmZud. LjO EnHrriHnk D9U Tvdrquaa HSCfM Mnn Ac^FltnCant X.nmiitCaalt f^itt* Lddud Lopa Count OpteEltctai(c(C«int UHT TK^Mlogtit Cewat Digiy T«c4nqMa Count, 2 vd. Alft^d WqCpfOOtt M * COLHtv 2 w< 50^ EglKATrOWAtflOOIfS 2U0 K.SO 2U0 t»^ 2gio «£0 ThlH boete IT* bnnd rwv & r^tMnla invui DW pub- Edwthtoieta. Altwdbowdaxo^itflf rwbd. LabEip«ftrMnliD>^TMh(«e| PUR TnCooJiaaek.[jneialir(io<(|,Sim« IlK AaHcnfcfylirMiuaaaPioviniffoia.lnM PtJR ElKMty 1 -7,1iHf, Hiyiln tHK) D«HnllMli>gUMvUi6 to En oo—Vio Ectnmiea IZiO ln*i«IMVM«UnlSr*Rii,BMr«SliE(l.|KlO «.» QUUB««cnE«,TelMni2n)Ei|>o(t MS AHihnn»GuidttoPTielc^8Klrtiiic«{io^ 3.75 nUtd Bk***ini:C«uti,Sunltii.2iid 11J0 PlnoiplttolElK*sy(l.3rdEd ^X DigUFlnlnwit^RivdjRJEd. 14.50 LcDm Tech 1755 Osgood St.. North Andover. MA 01845 CALL: 508/682-4936 FAX: 508/689-9484 ORDER roa FREE: S0Q/343-14S5 ec NEW PRODUCTS continued from page 22 Expansion from stand- alone data logger to com- plete data-logging system is simple and easy. As many as five data loggers (for a total of 80 channels) can be networked togetfier using the RS-422 ports at the rear of each unit. By wiring a network into a PC, up to 800 channels can be monitored. No programming experi- ence is reqiiired for set up. Once data is taken it can be sent to a printer, logged to a PC, or sent to one of the DB-2000 Series data buff- ers. Suggested applica- tions are in temperature monitoring and control, field-environment experi- ments,' benchtop data gathering, industrial-equip- ment monitoring, and re- mote data gathering. Prices for the expansion data logger range from $995.00 to $1295.00; the DDL SW applications soft- ware and LTN-03 Labtech Notebook software cost $495.00 and $995.00, respectively; and the JCV'W I/O module costs $345.00, A complete line of accessories, including cables, adapters, data buff- ers, battery-backup sys- tems, rack-mount kits, and driver relays, is also avail- able. — MetraByte Corp., 440 Myles Stand- ish Blvd., Taunton, MA 02780; Tel. 508-880-3000. PRESERVATION PLAN ON IT Wrile: Natioiuil Trust foi Historic Pieservation Department PA 178S Massachusetts Ave, N.W Washington, D.C. 20036 » RE-SHOPPER fg ^-UKELVlfl Electronics INDUSTRI AT DISCO AL QUALITY UNT PRICES BREADBOARDS FOR LESS! Durable - Made of the highest QUALrrY pmSTiC - DESIGNED TO WITHSTAND THOUSANDS OF INSERTION CYCLES P rail I Kill Rg, Slock No A 680093 B 680097 C S8009S D 680099 Contact Points 500 840 1380 1580 YOUR COST $ 4.25 ea $ 5.95 ea $11.75 ea $15.75 ea lililsSliU The Professionals ' Choice with ZOMHl FREQUENCY COUNTER excellent tor COMPUTER TV, VCR REPAIR and ENGItiEEmNG. YOU CAN'T '^O^'E'^ BACK GUARANTEE! GO WRONG! D LOGIC TEST ■ DIODE CHECK D CONTINUFTY TESTER ■ S FREQUENCY RANGES D TRANSISTOR hFE TEST ■ 5 CAPACITANCE RANGES D LED TEST VERIFY QOOOfflAD M 20 MHz FHEO couwTEH n AC / DC VOLTAGE MUSES ■ AC / DC CURRENT UHOES CASE - Yalkiw. Durable. BackSmrvd WIRE JUMPER KIT Stock No. Description Polnis YOUR COST 330290 350PieceSQ! S 7.75 63 130 DAY MONEY BACK GUARANTEE! rroi e ->^ PROTECTIVE CARRYING CASE Stock No. 990094 $9.95 ea '69 95 StKKNS. 090092 K.LS. SYSTEMS Kelvin Interface Systems NEW HARDWARfi NEW SOFTWARE USEP FRIENDLY 199 EDOCATBHAL AlCTrVITY GET 5 COMPLETE CLASSflOOM SETUPS FOB UNDER $1000 robotic control system AVAILABLE tor IBM or APPLE SYSTEM mCLUDES: m RoboUc Ann ■ K.I.S. lnwrf*e« ■ iJoyslicks ■ Power Supply ■ Sotlwate Defflonttratlon VMeo UPGRADABLE - adds the ABiurTTO cwhthoi. AN ADOmOfUL 4 OC MOTORS UP TO 1 AMP EACH FOR PROBLEM SOL VINO *CnvmtS SUCH AS CONVETOBS, ELEVATORS. PLOTTERS i ROBOTIC CARS. KELVIN 100 95 23 stock No. 990087 AC/OC VOLTAGE OC CUBHENT RESISTANCE DIODE TEST BATTtRV TEST LOW BATTERY Warning ACCURACY 4l-aiV. KELVIN 150 $ 29 stock No. 990090 ACIDC VOLTAGE DC CURRENT RES)ST*NCE DIODE 4 BATTERY TEST LOW BATTERY Wtmltig ACCURACY t/ 0.5% COf/TINUITY TEST TRANSISTOR CHECK 95 INDUSTRIAL QUALITY nnm YOU CANT KELVIN 200 IGO WRONG! 39 95 stock No. 990091 ACJOC VOLTAOE AC'OC CUHREHT RESISTANCE DIODE TEST LOW BATTERY Wimlng ACCURACY v- 5% COKTINUITY TESTIBUZZEH TTtAliSJSTOH CHECKER CAPACITANCE CHECKEU 30 DAY MONEY BACK GUARANTEE! CARRYING CASE Sladi No. 990093 M.95 «e TIMER - LM55S Stock No. 600021 20 Qf ea. (in too* Q^) ffl] L.E.D. RED (inlOO+Qty) stock No. 260020 6g Transistors {inioo+ oiw 2N2222 ISgea. PN2222 .OSpTea. "^ Project BUZZER 6-9V DC, 80 dB Stock No. 680069 $1.59 ea $1 .39/lOt ea. 11 9V Battery Snap & Holder Snap .15 ea. .10ea/ioo+ Holder .20 ea .IOea/1004 LAPEL MICROPHONE Stock No. 850306 YOUR COST $2.95 ea CADMIUM SELENIDE PHOTOCELL 4$0 Ohms e* 2 IL, C rmfiimutri iiart<. rasrstincfl 225 uhms Maa: votoofl 1 70V peak. P^aks al 69M angstroms. ^^ No. 26001 7 YOUR COST $ .99 ea. SULPHIDE PHOTOCELL 1,SK Ohrni © 2 ft., C minimum daifc restslsncs 75 ohm| M«x voltia* 17CiV aeak. Poaks at 5500 origslrcirns. No. 26001 8 YOUR COST $ .99 ea SUB-MINIATURE MOMENTARY PUSH SWITCH S4l«nl ^aion red piroh button molded J>{3u5Kig. ReouKW IM" panftl h&te. Ovftfall Jpnolh incl^jding solder luns « 1" RltKl tISVAC, 1 AMF>, Stsc*No. Color TOUR COST ItJOt 990002 Red DC MOTOR 1 .5 to 6VDC S»IK» No, YOUR COST Mt. 85221 1 $ .50 ea $ .45 ea $.35ea $ .28 ea ,-iB- T QUIPMENT SOLDE WELLER MARKSMAN SOLDERING GUN Model SP23 Fealtiorweighl 1-3/4 OJ,. S5 watts (or PC vrertt. Ideal for reaching Inio those hard to get spots. ReplaceatHe tip. Stock No. YOUR COST 6+ ^ 810002 $8.55 ea S7.95ea SOLDERING IRON HOLDER Model PH60 SDldering stand with ba$B. sponoe. For WidP, WPZ5P. WP40P, and ironi wilh Blrrol diam»t»tj up to 1V32'. Slock No. Deacrlptlon 810041 PH60Stand 810042 Replacemenl Sponge YOUR COST $13,78 ea 6+ $13.09 ea $ 1.89 ea $ 1.80 ea KESTER SOLDER RESIN CORE SOLDERS 1 LB. ROLL Mon-Corro5,vo Flux Heain Core Slock No. Inch Ola, QA. 580010 1/S4" .025 £3 5B0005 1/32" .031 21 580001 1/16" .062 16 580011 3/32- .093 13 64/37 60/40 60/40 60/60 YOUR COST $11.96 ea $9.35 ea $8.95 ea J11.75B8 VtfE STOCK A COMPLETE LINE OF FUSES FAST ACTING - SLO-BLO TYPE - PIGTAIL 3AG FUSE BLOCK phmolK. 1/2* 1 71V tong. ForlM" X t 1/4" leng hd«L SoUtr lua conn«ctionB Stock No. YOUR COST 380030 $ .45 ea FUSE MOUNTING BLOCK Dual hjH blocks 1^4'x1' long. Slack tfik*lilB base, Fery4'x1 IM'tuw Mounting centers S/S' MS.Etnun]. Stock No. YOUR CC«T 380010 $ .62 ea FUSE POST TYPE HKP BaywetMe. 2n5T.lor1M"nri«' fuses, 1 S Ampere 2SCV, Panel nol« slJ9 IJS- (12.7mni). CcimBl»to witn mourtling nut Slock No. YOUR COST 380001 $ .90 ea KELVIN BRAND HI-SPEED, HI-QUALITY PRINTED CIRCUIT ETCHANT fteady-to-use MJuPon of feme cfiloride prinred ojcurl elcnant In ptaifSc aywajrtfrr. Stock No. SPECIAL BUY 440017 4 6.25 l>«'>^'°" KELVIN BRAND HI-SPEED DRY PRINTED CIRCUIT ETCHANT Cioaji, Birffl. •commica]. iixMi^ni99 St>vH iAo, 4 lb*, wtd mtkit a otilora of focorrwiemiod stock No. YOUR COST NEW PRICE 440026 $8.40 ea $ 7.00/ 41b bag KELVIN BRAND COPPER CLAD BOARD NEMA orade FR-2 IrIG* mick. unpunched dad wi ons txl*. StodllMo. SiM YOUR COST 440002 4 1/2" X 6" $1 .55 ea 440003 5" X 7* $2.40 ea 440015 8 1/2x12 1/2" $4.908a ETCH RESIST INK PENS BlddiL leh| kip pgn lor rmfong racitl drcuJla tSitfCiiy on PC bovtlS- Cbd t» rsrnqved wrth PC Boaro Sti1fMiri[j Sotuttor. Stock No. Mod*l Description Y0URC03T 440115 22-220 Draws 1/32" wide $1,48ea 440 11 6 22-222 Draws 1 /64'' wide $ 1 , 85 ea ■s: KEZ. WAL Electronics 7 rairchtid Ave. Plainvlaw, NY 1180:1 Call: 1 (800)645-9212 1 (516) 349-7620 (cirIl^e'^r'^I^'^s^e FAX: 1 (516)349-7830 ^*''° RE-SHOPPER itrs ELECTRONIC CLEARING HOUSE, INC. P.O. BOX 2006 • OLDSMAR, FLORIDA 34677 813-855-4740 • FAX 813-855-6326 WEATHERPROOF 8 OHM SPEAKER Sze 3"x3"x2'' can be rnounted Hardware irxduded 4.5' Cord 3.5mrji Plug #SPK305 •^~- $9.95 NEW riEM - VOLT PEN Determines pmsenoe oF AC vcrftage through insul- ated wires. Contact with bare wire not required. t.ocates live wires in junc- tion boxes, blown fuses, br^ks in insulated wire & cable, defective circuit bteakers, defective in-line circtiita, elc. ♦TKS10 1-4 $17.95 5+ $15.95 IC'S MEMORY CHIP/D'RAM • SOCKET PULLS 64K X 1 — 1 50 NS #IC64 $1.75 256K X 1 - 1 50 NS #IC25 $2.50 AXUU. EUCTROLYTTC KFT 50 PIECES 5 each of tlie followir>g values: 1 UF 1 SOV 3UF 1 SOV 2UF 350V 2,2UF 250V 33ilF 260V #AE50 6LIF 150V 10UF 100V 20UF 100V 1 50UF 1 SOV 220UF 100V $9.50 ZENER DIODE KIT 100 PIECES 5 each of the following values 3.6V 6-8V 18V 36V 35V 4.7V 5.6V, 6.2V #W2D20 a2V a IV 12V 16V 20V 39V 27V 43V 30V 47V 33V S6V ALL1 WATT $15,00 LED'S T t 3/4 Clear Lens; Light as Red #l£D25 Bag of 25 $2.50 ZENER DIODE KIT 1 50 PIECES 5 each of the fottcwing values 2.4V s.av a.Tv tev asv 2.7V e.OV 9.1V 17V 2TV 3.OT 6.ZV 10V 18V asv asv B^v 12V tav aov 3.9V 7.5V 13V 20V 33V 4.7V 8.2V 15V 22V 56V ALL 500 MW *MZD30 $22.50 MONOLYTHIC KFT lOOPiECES 5 each of the following ^lues 10PF 470PF .0O47UF 0.47UF 33PF 680PF .0068UF .1UF 68PF 1000PF .01 UF .Z2UF 100PF 0OZ2UF .016UF .33UF eeOPF .0O33UF .OZ^UF .47UF ALL MINIMUM 50V RANGES 5-10-20* #MK20 $10.00 3 AMP RECTIHER KIT 24 PIECES 3 each of Ibe fottowing values: 5400 5401 5402 5403 5404 5405 5406 5407 #FIFIK24 $2.50 CERAMK: DISC KIT 105 PIECES 15 each of the foUowlpig most popular values: (All 1 KV| (Some Short Leads) 5PF 26PF 350PF 910PF -OOtSPF ,oaj9PF .01PF #CD105 $5.00 RESISTOR Knr 200 PIECES 1 S 2 WATT 5 & 10^ 10 each of 20 assorted v^ues #REK200 $2.00 CAPACITOR KIT 100 PIECES Radial Mytar - All 100V 10% 1 each of the follcwfng values: .0015 .0058 033 .068 .15 .0022 .01 .047 .1 .47 #CPK15 $12.00 TRANSISTOR KTT PNP NPN 5 each of the following values: 2N4400 2N440a 2rvH401 2NS401 #TflK20 $2.50 DEALER INQUIRIES WELCOME. CALL OR WRITE FOR A COPY OF OUR FREE FLYER. PRICES DO NOT INCLUDE SHIPPING- FLORIDA RESIDENTS ADD B<¥o SALES TAX. MINIMUM ORDER S10.00 ~ COD {CASH ONLY) SHIPPING AND HANDUNG ADD S3. 7 S CAMCORDER REPUCEMENT BAHERIES FROM THE BAHERY STORE • Low Cost AllQWt Extra Spare Battsrlet • Buy Dlrict From Th« Bittiry Manuftcturar • Ellmlnata "M>iinry" Problim • Extanded Run Tims MixMi AvailaUa • 6 Month Warranty • Other Battery Types Available • Overnight Shipment by UPS 8mm NP-22 Sony (27.00 NP-55/77 Sony $31.00 E-77X Canon $46.00 VP-BP81 Olympus/Nikon $41,00 BP80 Panasonic $34.00 CB-120 RCA/Hitachi $49.00 NP-009 RCA/Pentax $49,00 BP-96FL RCA/Hitachi $49.00 VHS-C BN-V6GU JVC/Zenith $31.00 VMP-51 RCA/Hitachi $49,00 'Add $4.00 shipping & handling per batteiy BittBrIsc an our only butlnoss, The triie vatue o1 any battery system is determined by service, performance and dependaWlity. Make your choice Periphex. Nobody has a better battery or offers a better vatue. itHIH?RlPI10Xlnc. 149 Palmer Road . Southbury, CT 064^8 {BOq 8344132 . ftl CT (21^ Z64-3S85 ^^ FAX: [203 2e2-aiK3 VHS COMPUTER DISK SERVICE SPECIALIZED DRIVE REPAIR EAGATe5'- ST 238 ST 225 W>N1SCB>BE6;;'_ 3435,3^38 3A25. SA^--^. - M,N>SCR>B£3v. a425. 8438 $120° SEAGATE ST 251 Special Low PHces! FOR SALE NEWn 380mb SCSI r 6ms M'NISCR,BE9380S * 1.000.00 CALL FOR PRICE • Class 100 clean room • Servowriting capabilities (Call for prices] • Volume discount • 1 20 day warranty on all repairs • 7-10 day turn around time • 24 hour turn around - ADD 30% • Ask about our data recovery (Call for quote) COMPUTER DISK SERVICE 3537 OLD CONEJO ROAD, Suite #115 NEWBURY PARK. CA 91320 PH (806)499-6356 FAX (806) 499-0346 \0 HE-SHOPPER SPECIALS LIMITED QUANTITIES CABLE CONVERTERS SIGMA SIGMA 550-86 CHANNEL *99.95 EACH TOP CHANNEL ROLLOVER, LAST CHANNEL MEMORY, PARENTAL LOCKOUT, FAVORTTE CHANNEL, SURGE PROTECTION, 4 db AMP, DECODER COMPATIBLE, 1 YEAR WARRANTY. y7y*y5 each slot $75.00 EACH 10 LOT $67 .SO EACH 20 LOT $05.0U EACH 50 LOT COMING SOON 'NORTH COAST' CONVERTERS TOP OF THE LINE SAN JOSE SPECIAL! SCIENTIFIC ATLANTA 6700 A/B *99.95 $7" ."5 EACH SLOT $75*00 EACH 10IX)T EACH $69 .95 EACH 20 LOT $65 .00 EACH 50 LOT 54 CHANNEL A/B TWINLESfE, 10 CHANNEL RECALL, CHANNEL 3 OUTPUT, ZENITH COMPATIBLE UNITED ELECTRONIC SUPPLY P.O. BOX 1206, ELGIN, IL 60121 (708) 697-0600 RE-SHOPPER i BATTERIES Replacements (All New — Made in the U.S.A.) CAMCORDER (batteries) JVC GR-C series 8i95 PANASONIC PVBP80 (12V @ 2.3anips) mM LCS2012-VBNC 135^5 LCS2012.BVBN ..mM RCAfHtTACKI FuiisteVHS mss VH&C ....mM SONY NP22 J32.95 NP55 $32.95 COMMUNICATIONS (complete battery packs and Inserts) ICOM PB.2 (SOOmah i, 7,2V)- (33. PB-5 ISOOmah ,,■ 7.2V) ,S44. '7(S)(I2M(nah .n3.2Vl .163. '8(S)(1200riah< 9,6V| S59. 'base charge only, one Inch longer KENWOOD KNB-1 ISMmati -s 10.8V) S39. KNB.4 (2!00fflah ft ?.2V| 165, P8.1 jllMmahiS 12V) S61. YAESU FNB.2l50Qniah,s11V) S20. "FNB-10(eOOmah'&7,2V) . S30. "FNBKHSIIlOOOmah t7,ZV) .. S45. FNB-12(500rrahei2V) 144 ■*FNB-12|S|(600niahJl2V) S49. "same size case as FN B'12 SPECIALS!!! CELLULAR BATTERIES AMD ELIMINATORS MOTOROLA PANASONIC MITSUBISHI OKI NEC N OVATE L NOKIA-MOBIRA DIAMDNDTEL TECHMQPHONE MOTOROLA-FLIP PHONE SERIES AOUIOUOX CORDLESS PHONE (batterjesi ATT 4110,4310,5210,5310 ,.*9.00 Freedom 400 (8.00 Nomad 200,250, 400 (8,00 COBRA CP-100, 200, 300, 400, series $8.80 CP-454S lo CP475S series 19.00 PANASONIC KX-T3805, PQP-25F30tt $11.00 KX'Series most models. $ 8.00 SONY SSP-flO $9.00 UNIDEN EX-series most models .$ $,00 XE-series $9.00 MasterCfird and Vtsa cards accepted NYS residentB addS' i^'c ^iiiles tak Add S3 50 lof postag^handljng. (800) 442-4275 Prices subject Iq chiing'e vyilhout nohcG | DEALERS WANTED (QUANTITY DISCOUNTS) BA TTER Y-TECH mC. 28-25 215thi PLACE, BAYSIDE, NEW YORK 11360 IN NEW YORK (718)631-4275 ■ FAX: (718) 461-1978 CIRCLE 347 ON FREE INFORMATION CARD * 11 voy don E 4n " '%* 'or il - Cuk^ambJllfiv pji£h,k • Hiqh cjipaciEf p^ckt > NiCk«l CadmiLfin Ctlll - Ltlhium TELEX; 510G0 16795 MS-DOS EPROM PROGRAMMING SYSTEM NEEDS NO INTERNAL CARD EPROMS 270S(5«upply) 275S.2716 27016,2516 2532*, 2564" 68764* ,6 876S* 2732, 2732 A 27C32, 2764 2764 A, 27C64 27128, 271 28 A 27C123, 27236 27C256. 27512 27C512,27C010* 2701 0',27C1 001' 2e64A, 2825S* 8748', 8748H* 8749*, 8749H* 87S1',e7C51* 8752*, 8744H' 'Socket Adapter Required (OtagnuTis InclixM^) CONNECTS TO YOUR SYSTEM'S PARALLEL PRINTER INTERFACE -A FUU- FEATUflED, EASV-TO-USE SYSTEM WORKS WitH AMY DESKTOP OS LAPTOP MACHtNE ' ADAPTIVE, HCOH^EPEED ALGORITMU MIHIIWZE3 PROGRAMMJHG TMJE^ AND IMSUHES VALID DATA • SYSTEM PROGRAMS ALL STANDARD 0€ViC£S OR EOUrVALEHTS FROM AHY MANUFACTUnEn < ALL SVSTEU COUPCHEKT9 FIT NEATLY INTO CASE FOR TRAVEL OR STORAGE SYSTEM SOFTWARE COMMANDS . PROGRAM EPROM(S) FROM DISK FILE . READ DISK FILE INTO BUFFER . READ EPROM(S) INTO BUFFER SAVE EPFIOM(S) OH BUFFER TO DISK PROGRAM EPROMfS} FROM BUFFER COMPARE EPROM(S) WITH BUFFER . COPY EPROM(S) . VERIFY EPROM ERASED . BUFFER EDITOR . SELECT DEVICE TYPE .DEVICE CHECKSUM BUFFER EDITOR HAS IB BYTE LEVEL COMMANPS FOfl DETAILED OPERATIONS SYSTEM INCLUDES: PROGRAMMING UNIT POWER PACK, CONNECTING CABLE, OPERATION MANUAL L SOFTWARE SOFTWARE AVAILABLE ON 3 1 12" OH 5 1J4' DISK~ TO ORDER SEND CHECK, MONEY ORQEft, Vtf^iTE Ofl CALL: $239 ANDRATECH P.O. BOX 222 M1LFORD,OHIO 45150 (513)831-9708 CALL OR WRITE FOR UORE INFO. - ADD $5,0D FOR SHIPPING - $4,00 COD VISA MASTER CARD 32 RE-SHOPPER CABLE TV "BOXES" Converters— Descramblers Remote Controls Accessories • Guaranteed Best Prices • • 1 Year Warranty— CO. D.'s * • Immediate Shipping • * FREE CATALOG • Call or Write TRANS-WORLD CABLE CO. 12062 Southwest 117th Court Suite 126 Miami, Florida 33186 ■■■■ 1-800-442-9333 /C2S^ MasterCard)! Call £or Outstanding Pricing on Tailored Computer Systems ^^ f. (iLWfiYS fiT B DISCOUNT MOTHERIOAROS • XT ■ 2ee ■ MS • 4U n Smhf iBcbo H 6i0 kill. 8 slflts. WBIOS i CPU IT lOnWi! lurto a MOt Uti 1 tlOls » BEOS i CPU OUR lEST SELUMI VUI 1ZMU HOtlKIKWHD t^fflhi; ?S6. (b3 14 Jmb. $ sJdis AMI BIDS BiE^ sin n9 M tm-U. eatry ^. «M. & tn ITKD *I»T CHIP, EEMS. Snu E39 »T ?»5-1!, Baby ST, OK a 10 Id* NMt CHIP, EEMS. awl Ui AT. 3»t Su. Bjtfr Sir. Ihs. 0: le Bmil, NEAT CHIP EEMS. Stud X& AT, 3$$-25.'^ , aiZh Clcfte , BiEry S,f.eiK.101SniEl,SSlDI£,AMI8IQS.1139'l37S CONTROLLERS FOC-I. 360H.720K. XT OWJ » LOHSSHIME RK + 3KK7JIBC1 Jmb.1 WItlll.n.'AI 31 SIVER FDC, ClHltllll 4 InlcmU DIMS, XTiAI All Drwe Typw 39 CWinCTICAflD II. t aiKB. BSOKT^OK 1 ^mbl Mnrll 94 CBUPHCTICIWD II, CO-taH. ClflS S Dr, Nl Typej .75 tONFWrnURD IV. i Dr, All TylKS Co-CiiEI fH Slind Alont BiKll Fros Any Drive, turf Injljiiution 112 LONGSHINE 6310 HO. Clll! i HiO. MFW, ITT Only 41 WESTERN DIGITAI. >[T-GEN. CMS I HO. MfM. XT .S3 WESTERN DlGITll ?n. lltrB ? HO BU. XT 61 WESTERN DIGITAL 1(»3-MM?. 2f0 ?MD. ! 1. u™. AT IK WESTtRK DIGITAL 1006-MM? IFD7HD. I 1. MFM. AT tIC WEETEF!N DIGITAL H»3-SH?.2F0?HD. M. All, AT 1» weSTfRNOIGITAi 10C6-SB!, JF07HD, I I. Rli, AT Ul LDNGSHINE KM. ZFI-'IHD, XT OnF( 75 mNGSHINE mS}. !FO-JHD. 1 1, MEM, AT 73 WA.3. ;fO:3HO ? 1. MfU, AI iS WA-tVF!, !FDr2HD. t:t. BLl. AI ... . 8S WA-6. !fD'7M0. 1.1, MfH,AT „.. 77 DTC 7?B0. 2fD.'!HD 1 1. MFM. At „ 99 EFTC 7J87. ZfO.aHO. 11. FILL. AT ....^..^, 131 POWER SUPPUES 150*XT. SandirdSat fflfPC.XTSystBms ...^....l-., 38 15011 XT. UL AwilWKl 4S 2D0* XT. Stanrlard PItysmL Size lor PC XT .... 4i 200* XT. UL ApprovBl S! ^76ti AI SUAdin! F^u^ Srn Im ISM AT . S4 JJOnAT UL Aconwti M FLOPPT DtSK DRIVES TEAC3H1K. 5-1-1. FDSSBFl. BuaBiMc. (Besll . K'M TEAC 1 2lll6. 5-M. ED5SGR. B«st.Bllrt. (Bsaj TUMI TfAC720i;, 3-1-3. FOJSSSF, wlft 5-1'< HI, Biegt Onl^ ... M TEK 1 MtHb. 3-1,'2. fD335HF, Wlin 5-1. i Kil Biege 74 FUJITSU BBOK. 5-1.4. M.;ut A aiir:k'BHiCS SOCtiBOO SUPER VGA 1024l7ea I8BII .. VI f ATI. K»i560 BS™ 256 ATI OEM. 10241761 ISEil. 25SK. (VIEW PERFECt) . . ATI WA. OEM. KI2-11768. 18811. 2S6i;. w.'Mbim. IVP) VGA BOOlBOO (Oik), 15Blt FMBS z:*^, MOBILE BABY SITTER 'MVi^f- PorubiB WIrslBU .JSm.^ii: J> MohltDring Sytt«iTt 35 14 . 112 .. n 112 179 205 sad 39 Quality & Service to the Smart Mai) Order Shopper for over 4 Years 7S .. 79 112 110 130 229 tu 349 379 349 539 . 495 MONITORS Ail. OEM MONITORS MANUFACTURED BY SAMSUNG MONOCHROME 12" yonda 12O0. JJtlK348.Am6T.-S 12' MM OEM 1252, 7201350, AM3.. Tilt X Swml 14- MM OEM 1457, 7!0j35O, AMB .-mi, FHI Scr. liS 14 VOLTBON GM-1489. 720l350. AMB -WW. FrS. T-S 14- EVERVJSION. 7^)j3S0, Amb , Fill Scrmi. T'S ... 14 MMM OEM HM14641:. 64[(iJl». S! 001. T.S 14 MM OEM MMMI4E4W. 341^200 41 Dot. T, 5 14 MM OEM 1153M. 64tM«l. .31 Ool, IM i Swrwl 14' RELYSIS AE'5154, 3401350. 31 Dot, IBcst ValucI 14- NEC 3D, W?4i7M. .28 Do!, Aiuli>|!,-nL,T-S 14-yiEWPERFECTVP3.tD24x76339D(n,S0l(Y Tul>>,Sllirp 14- REWSIS BE-SISS, «««<10, 31 Ool. ATTL.T^ 14- VIEW PERFECTVP-Z. 6401480, ,29 Anjloj. TjS 349 14- RELYSIS HE-9S13, 720s4M. 31 BoL Arilog. TS 379 14- MM OEM 1463172011400, 31 Oot, Al«ll«j, T,S 379 M' NEC 2A, CUneni, 31 OoL Analog, Tin S Swml 54S INPUT/OUTPUT ■ MULJIFUNniDN CARDS SERlALCirfl, 2 F^rB, 2nd F*rlOpl.COM 1 * 2(ForXT] 13 SERIAL Care, ; F^ns. !nO PoH Opl , COM 1-4 (XT) Ilr?l SERIAL Cird. 4 F^rte. 3rd I 4lh l^irl 0;!. COM 1-3 |Xr,'AT) ... St^ 2nd SERIAL f^ri Dpi.— Catilt 4 Chrp Sfft— Pin Conneaor Conflg. rtqirired for proper cablfl XT.-AT .. lU'lB f»FWLLEL PfllWTER Card. LPTt Dnty.LfT- 1-2-3 (XT.'AT) SilS GAME CARD, 2 Puts, Allows AlUdimenlolSJOySOiis . , 11 GtaXCard, Ciknui t Clock On^, fiis inffi A Slol(j;ninir)^ XT} U AT|iO»1, 1 Sir, 1 far, 1 Gimc, COM 1-4, LPT1-2 !S2 AT I'D »3. 2 Sh, 1 Par. 1 Game. COM 1-4. PI.T1-2 ,. 27 At l.-O *4 ! Sti«L f EaraW. COM 1-2. LPT1-3 35 1-0 PLUS. Osdi. C^tndir, Parilil. Sinal. Gamt (lnrXT) 37 334(i WUIT1 1.0. ftTo 3841:. Cal. Clk. Sar. Pii. Gim« (XT1 39 MUITI ID. w Floppy CUr. Cil. Sir. Rir. Game (XT) 33 SUPER MULTI 1-0. w.'fkjpE* Cllr— Conlnils. 36C'720K, 1-2 and 1 44ir)b FDD. Ca. Clk. Etr, EHr. Came Pari! (XI) 59 BARE BONES XT lOmhi Onklop Banbon Sys. . XTAT LiU Ciu. 101 ICB. 150W PiS. Fkippr^ Cllr. 360 Floppy Dnvt. 2S6k M(mory 279 AT2e« 12mbz 266 Desktop Barebone System, to 4mb WB. 0. hjl Sin AT Cau. 220w P.'S. 101 EnhaiKM tteyboard. Fkipfy/KvQ Onvt Cootolier. 1 2mb Floppy Disk Onvt 493 MODEMS 12D0 EVi:, Iniemil, wrthPCTALKinSoltwlrt 45 1200 EVEREX. InlMnal. wnh BlTCOM Soltwan 74 12t)0 (jVC. Ekltmal. odhPCTAlKllSoltmre 5a 12D0 GVC Eitimal FtKiel Modem „ _ 7B 2400 OEM !0OM. Inlemil «i!h PC TALK III SolMVI 91 2400 EVEREX. Innmal mill BFTCOM Sollwaie _ , 13S 2400 OEM ZOOM. EMsrnal *ilh PROCOMM SofMnm , 105 Z400GVC. Eilerral, *nb PC TAtk l« Software 109 2400 GVC. EMtriul, mill PC TALK lU MNP Class 5 ISS 2400 EVEREX. EilemaJ, «n BITCOH Soltwan 199 SOmVAKE MS DOS 3 3 W.OW BliiC. MM Wfsnjii 5i MS DOS 3 3, Actual MICRDSOn , . 84 MS DDS 4 01 W'-GW Saslc. OEM \«!r Slim— No Bllic MlfflOl 33 MS DOS 4 01 W,'Anual MICFlSOFTSIim-No Basic Manual U MOUSE ■ TRACKBALL - SCANNEBS OMOUSE X-3cket. Store idur Mouse Wlwt Not in Use 3 00 MoiiC* PaC. Son or KiKt 3.0O Motise Slape. lidded Stage Placed o^tf ICB lor Mouu 9.5Q PS2 Mouse Adapter 4.0O J^slits Maaii; OKI IBM I CsmpsiltU'Mloic 909A ISM'Ak*! I5;1T Dealers Wanted ALl.FURFOSE dust CLLAlhTER ■LOWlAWji^Y DUST PARTICLES fHOM VCflS-COMPVTtBS- CAUUAS Ha.lL} A^ KEYBOlAnDS MAJCI -SWITCH »4 By (Tin Sest) MAKI-Sl*nCH 101 my fflit Besll KEYTKIKICS Kn Kv (Esalllin) 4Z 50 48 NIC SPECIAL 101 KEVBWflO TarttefOiai H functari Ktys on un SkM Omtr Stippilers AD Piia S99 Keyboani! Ow Pilci M (4 KEY KfTBOARO. fen-tW* ,. »4itfycHifflMv.Taci)i.-a«* _. 101 KEY Moo-Clitk CapaclUM lacDIj U FuKtion Keyt .^-.. 101 KEY KEYBOARD TattilBCIIi*. 12 Einvdlonkiys _ 45 40 43 KT-JO 101.-102 KEY «nh Mtisoll Comeal (Senal or Bus) Tracktaii Mouse. 20 DP I-B4O0 iiriaHi RKOIimon 95 I«W«.-OMNINEY.PLUS KEYBOARD ticm NOflTTHGATE-Tod mjl^ lianjres lo list, call or wnn lor Feature listtno 99 29 33 CASB DESKTOP CASES XT SLIDE. Sruidvd PC/XT. 4 Eiqnsict Qnvg &ir^ ., 3fT/W liks. ? Cxp Of. J ifiE Dr. LED-'lteset'>;ByiTiirbo . XT/ATLike. flpp-TOpCaalSamt K Aboviij 44 BAfflf AI 3 Exp T>r. 2 ln( Or LEOfFtEKT^KEY/Tufbo. XT si. fVS , 50 i*.'Olgflal Dsptiy „ , 5s KTSTD Disktop, 3 Exp'^lm Df, LEtk'ftBK'TftV'Tutto ^...,„.... 52 AT DELUXE DT. Satne u Nkhi. Hbivw Duty. BitUf Qui .,..,,„ £4 w DigrtJl Display , ,. ,. K MINI AT DT, Artracil«, w/SDOw P^S, axS-TM A IKS-T/Z BCp Df Biysplirel lnt3-l.'2HaDf Bxy. FHsAT«CTSrW/e 109 #jDt3(Ul DisptiyjLes5ln!3-^?Hd Bjyl 119 FLOOfi STAND VERTICAL CASES VEFT »'22&*P.'S S«S-li4Eip DrivH, NonDtptil 2lO ■hVijeOw UL Appovifl ftiwir S^ifiply ?39 VEFTT. w^DOw P;S. 3i5- 1.'4. 2x3-1 iZ EXP Or. 23i5-1 ^4 Inl H^D Bi^^. DIfl- DisO-l W VEFT. w,220w P.'S, 3)t5'V4 Exp Dr, 4*5-1^ V7 Hi ilrtDl, Dtsilat.[>ispl^ . 215 wi^flSwP/S , 259 MIO SiA V£RT, w2Kw P^. 3k5-1j2 « £k3-1^ Exp Of. Zi^m ID e«. FrixXTAATSmMDth«ftri»rd. Di9*til - 149 Ml«|| VERT. *i'20Ciw P^ 2x5- 1 z+lxG -1 .■2 Exp , 2k3-1 ■■2 ht, Rts XT M/S 0(11^.125 QAfiL£55 KT HiRj Drifrt Dau CiWe. 20Pin Dju CiWt Only . 3-00 XT Floppy Driva dbk, For? Ftoppy DfnM ConnetiwriS 3 95 AT Cahl* Set, 3 CihlB. i tof f DO. 2 For Hani Dfiw 5.M ftrjiiBl PnnUf Catjta 6 : 3.95 PinJW Priniw CabM $; WokJeil 4.95 F^r^lel PrTnlwCablfl tO; MoWsd _ „„ S,95 i^raJW PnnnrCabta, C«ii«miic l& CWlrcw*;, 6 : , S.9S SptJl MwlMn CiWe, &. Male to Ftmih ^ 4.M Strlai Modnn DiUt. 10: htaie to Fimalf &.95 ACPOW£RC0nO. Fof njwer S^IJ^pty ttj AC DuHrt 3.00 Y Cabli, Adaptor [Q Expand Ho pl ft>wr OulJIUtS Of P^ 3.00 KiytoartE-KtwtjDfl CiDtj, 6^30 " .2.g&3 95 MOAitor Ejpanswn Cable S-'IO -' 3,9&'$,96 Seruj PDnAi]ap[D^9 Pin Fffisueto 25 Piflttad 5,00 GloiHr Ctungcf . Female to Femala , , 3-50 tiHtder ChauflH, Mala to Make ,.., 5.00 UGACibte. 9 Pin 10 15 Pin to 2S Pin , .. ...„.^.^.^,.^.^ lO.OO MiA Expansion l^aMa. Univrrul torSony, NEC ^ 9.00 5ii(fle Pnjttttor. 6 OyHji Ptwuf Sbip, UL Approwd ......^^^ ..._. 5-95 Power Cenitr vritti Suiga Prai«tiQn. SitJ Under Monllar tS Ba[tBi> Pack Fui AT Comdmtjr. .How 4 AA Sia BattBiiii 100 Sselfct^ 2-1/2 3,00 ^xaJar hicilttar -, ..-, .,,,, 2.O0 At Powfrr Cord CofliMcl? BrtwEWi P'S and AC OvM ...„ .., 300 AT Fbikm Far MounUng F)(>ppyiHanS Dnv«. Sfllof 2 ,.., „... 3.00 KT Face Piatt* l.&lKl£>. Cwtr^ Empty Driw 9tf ?-00 AB SiWiti:ti Bon. Spcnly '^pc oJ Connvction , , 14.00 Disk DfMS Cfeininfl KiE lor 5-t/4 Dnves 6-O0 DiSkDnviiCkamivoKitlQra-li^DTtvd) 6,50 Pnnlar. iCayboarfl. fc^joM. Otjning Kit „. .- 6-50 PnriSer stand, Unrvenal, Fits All Prinurs 6,00 Pnriar Staml nWih P*|Mf Trjy, H«2vy Duty Wrt Oomt ......_.. 11 DO Pnmer Stand WKh Enckiad P^rTny „ 17.iXl CPU AdJ Stafld. Set Dsskiop Sys on Ftoonn *r1 ftal ..... „.„ 9.D0 Efl'37S A ? ttatifln. RF (fequtncy moniEorinif sysiam Ttan^mitiir unii: plugs inlo any AC ouOel. m«jnl$ tisH eavv dirty higEi temp vk^nt wut lei;dS- firu line facing partt bviit to ^h landanis 19.BD' Pomt^i »lld stale amplrtar FulurK incFvtfe'burlE-m jwtttTi- ipHKfjibie alarm airen. whtstlQ. Iigtit. jHstpE gnp press la taFk switch wi control. aiKE^i^ider Strap-SCMll bHttries-jnotsuppt DELUDE WECAPHOHE 129.35 WITH SIREI*. WHimt * LKtHT '^'Hllh U-t >- BiilDia- 9-i,i6" Wgi,3'/^-|bi w.-o Ban Wtflag* 20WW» Elfw Rtv» l200Ft (J:? 2115 Old Oakland Road San Jose, CA 95131 One yea* wairanly uoless otherwise indicated- • '30 day warranty- XT* AT* i Jewr" Are Regrsl.ird Trat**m»r* . 01 rnlfrm.t,on*i eusinest laaciiinM. - Piic»4 ari? suhtKi lo chanffff wirtiout natic*. $1 Rebate per $100 on all phone orders (ex., $5.00 rebate for $yOO order) 408-432-7380 TECH SUPPORT 408-432-7557 FAX 408-432-8622 Call Of nrile lof shipping details A S3.00 handling charge is applied W all orders plus a nwimurn ol S4 00 Ireigh! 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Box 280298 DllUs, Tims 7$228_ 7400 7¥M .17 7474 .30 741 S2 .50 7«01 .17 7475 .35 74163 .50 7*oa .17 74S2 .30 741 H .70 T4W .17 74»3 .45 74185 .70 7*0* .17 74M .30 74150 .90 7405 .17 74«5 .55 74173 .75 7«« .23 74M .30 74174 .70 7«07 .13 74«a .30 74175 .80 74M .23 7490 .37 74170 .50 740B .17 74W .30 T4177 .50 H\0 .17 7493 .30 741 M .50 7*13 .33 74M .30 741 ei .35 7<14 .25 7497 .30 741 N .SO 741 S .20 741 K .35 741 M .25 7417 .20 74107 .20 74105 .00 74ZC .17 74111 .35 74187 .25 74JS .2$ 74120 .30 74199 1.00 74H .17 74125 .40 74221 .M 7437 .25 74120 ,1B 74251 .25 7421 .a, 7413B .19 74258 ,78 74afl .15 74130 .18 742(5 .50 7432 .27 74144 .20 742J3 1.75 7433 .25 74145 .40 74278 .50 7437 .17 7414« .«0 74278 .50 743a .23 74150 .25 74203 .50 7440 .19 74151 .50 T430S .M 7442 .35 74153 .35 74355 .50 74Sa .17 74154 1.1» 74307 .90 74S1 .1« 741 SS .M 743U .30 T453 .22 74157 .30 74370 .30 7454 .22 74110 .iO 74390 1.40 7473 .2S T4151 mi .50 ^ ■ 1 LSM ■ .14 LS1Z2 m .35 LSJ41 .M 1 LB02 .14 LS123 .45 LS24: .65 1 LS03 ,14 L5125 .30 LS243 SO 1 UM .14 L312« .»5 LS244 .5S ■ LSOS .14 LSI 32 M LS245 SS LS09 LS10 1511 LS12 LS13 LS14 LS15 L$20 LS21 LS2S LS2T LS2S LSJO LS32 LS33 LS37 LS3« LS42 LS51 LS54 LS55 LS74 U75 1.SS3 LM5 LSM L3W LS92 L595 LS107 U109 L£1t2 US113 LS1 14 .14 IS133 .14 LS138 .14 t.S139 .14 LSI 45 .20 LSI 45 .25 LS151 .30 LSI 53 .£0 LSI 54 .14 LSI 55 .15 LSlse .14 1,5157 .20 LS15S .15 LSI 60 .14 LS161 .10 LSI 62 ■iS LS163 LSI 54 LS1E5 .35 LSI 65 .15 LS1E9 LSI 73 LSI 74 .22 LSI 75 .25 L£1S1 .30 LSI 01 .45 LSI 82 .20 LSI 93 .35 LS194 ,30 LS195 .30 LS1«e ,2« L5197 .20 LS221 .25 LS240 .25 ,25 .24 .24 .20 .20 .25 L52S1 .45 .35 LS253 .40 .36 L5257 .39 .75 LS256 .45 .35 LS25S 1.00 .35 LS2BD .40 .35 LS2S0 .59 LS273 .50 LS270 .42 LS2S0 .30 LS2a3 .29 LS2W .25 LS29S .39 LS323 2.35 .45 LSm3 1.00 .36 LS357 .45 LS3«3 .50 LS35S .75 LS367 .90 L5366 .80 LS373 .39 LS374 .35 L5379 1,JS LS377 .45 LS37a LS3S0 LS393 WE ALSO CARRY POWER SUPPLIES 74S 74ALS 74F 74 HC 74HCT CMOS LINEAR UART zeo PflOMS CRYSTALS DIP SWITCHES DSC1LLATQRS DRIVES VOLTAGE REGULATORS F.D. CONTROLLERS CLOCK CIRCUITS DRIVERS RECEIVERS CRT CONTROLLERS MUCH, MUCH MORE! CALL OR WRITE FOR FREE CATALOG. 9502 2.00 5920 1.25 5532 ,.., 2.70 5530 3.00 5532 4.25 9S45 1.10 6551 2.40 .05 .65 .40 .52 LS541 .95 L3545 .75 LS«40 .50 LS570 .50 26LS32 .79 35LS2569 1.50 .00 .75 .30 .35 .30 .50 .45 .35 .75 .80 .60 .75 1.00 i.a) .75 .75 .60 500O 5S02 5603 5005 5609EP S509P 6610 5B45P 6645S 5850 1.40 2.50 3.0O 2.99 2.75 2.90 1.35 2.M 2.20 1,75 5552 6558 3.90 3.99 60«0 3,80 MAOt£P 1.25 50A40 4,80 50*54 3.00 C5S09 4.0O 50B1D 2.00 66B49 4.»5 B6B54 4.00 THREE CHIP SET 1486, 1489, 16450 B.G. SPECIAL SG.SO VOLTAGE REGULATORS NETWORK $25. K) (LAN) NETWORK THAT REALLY WORKS! CAUL OR WRITE FOR DETAILS, LM317K LM317T LM337T T605T 7eM09T 7e05T 7I00T 7S10T 751 2T 7S12CK 7»W12T 781 ST 1.40 .50 .90 .35 ,25 .26 it) .20 T615K 781 SK 7824T 7875T 7M5K 7905T 79M05T 7I12T 7912K 7>t9K LM350K 7tM09K .50 .60 ,39 .30 .75 .40 .29 .35 ,9« .30 3.35 3.76 DYNAMIC RAM 3108-4 BKX1 1.» 2115-4 1 6KX1-SVolt 70 4027.4KJ(1,250 n.l. ,M 4116-16KX1-250 n.l 40 4116-16KX1.200 n.> 75 4116 ieKX1-150n.t .....90 41E4-B4K 200 lU. )0 4164 150 n.l 1.25 41E4 120 n.l 1.50 4164-100 1.75 TMS4416-1E«X4-1S0 n.l. ... 2.75 4464-150 2.25 4444-120 2.59 4464-100 3.05 4125* 150 n.t 1.79 41255 110 n.l 2.05 41295 100 n.l 2.39 41255-80 2.M 41255-60 4.D0 1 M>g- 100 nj. 8.00 1 M»9-60n.i 8.35 41429e-S0 n.l. 296 I 4 9.00 SIPPS « SIMMS AVAILABLE STATIC RAM 2016-2KX8 200 n.l 1.O0 3101-1 - 2S«X4 SCO I1.1 75 21L02-1 390 n.l 65 2103AL-4 LP. 450 nj 49 2111-1 296X4 900 n.l 1.00 2113A-2 3.50 2114L-3 1KX4 300 n.l 49 2125A-2 mXI 70 n.t 1.70 2147 4KX1 1,95 5116P-4 1.20 6117 1.20 6164-15 1.40 62355 33KX6 6,90 EPROM SPECIAL t bou^t ■ IK^ quanllly d 3706i, 37164, 35331, 37321, 27641, 27118 ■ nd 17256 from m compulii' muiu1tc1ur«r wtio ridMlgnid Ihilr boardt. W« nmovid thim fnyn locktl*. iriM^ and vaHflad m«m. and ncnv «1 oftar tha savinga to you. Complata Hllilftdlofi ^uarantaad. Your Chotc* 2705 1.20 2715 1.79 2932 2.00 .2732 2.00 2764 2.39 27126 3.30 27396 389 10/6.00 10/19.00 10/17.50 W17.50 tO/lODO 10/27.50 10/32J0 W( Alto Htm Ht» EPflOMS 8000/80000 6031 0035 6039 60«5 6056 6067 6087-1 6057-2 8066 60Ce6 8155 8156 6202A 8211 8214 5216 5224 8228 5237-5 5143 5150 1.95 1.00 1.00 1.99 1.55 67.50 167.50 127,50 2.70 .40 2.29 2J5 6.00 1.25 2.08 1.25 1.25 1.75 3.60 1.75 1.8* (16450) (16990) 6251 6253-5 6254 5255 5295-5 8157 8299A 6159C-5 8275 6179 tlM 6285 6367 8280 6530 8741 8746 8749 (755 6.50 12.00 1.10 1.75 1.80 1.50 1.75 1.50 1.65 2.10 10.95 2J5 1.49 3.50 2.49 3.50 3,00 7.00 7.00 7.00 7.0O 60266-6 PLCC 6.50 80267-8 191,90 60167-10 227.50 V-20-10MHZ 6.50 TEXT TO SPEECH BOARD PC/XT COMPATIBLE. MAKE YOUR COMPUTER TALK! ASSEMBLED a TESTED ADD $3.50 SHIPPINO a HANDLIKQ $69 95 A VEHY POWERFUL ANO AMAZING SPEECH CARD. USES THE NEW GENERAL INSTRUMEKTS SPCI25S-AL2 SPEECH CHIP AND THE CTS256A-AL2 TEXT TO SPEECH COMVERTEfi. THIS BOARD USES ONE SLOT ON THE MOTHERBOARD AND REQUIRES A COM SERIAL PORT. BOARD MAY ALSO B£ USED IN A STAND ALONE ENVIRONMENT (EXTERNAL POWER SUPPLY) WITH ALMOST ANY COMPUTER THAT HAS A HS232 SERIAL PORT. TC USE THE BOARD IT IS ONLY NECESSAdY TO SEND ENGLISH TEXT TO THE RS231 INPUT ON THE BOARD. THE BOARD INCLUDES A 1500 BYTE TEXT BUFFER AND HANDSHAKE LINE TO ALLOW YOU TO SEND DATA TO THE BOARD: THE SAME AS YOU WOULD SEND DATA TO AN RS333 SERtAL PRINTER. YOU CAN SET UP BATCH FILES THAT WILL MAKE YOUR COMPUTER GREET YOU WITH ■QOOD MORNING MASTER," ETC. EVERY TIME YOU TURN IT ON. DEMONSTRATION SOFTVKARE AND A LIBRARY BUILDING PROORAM ARE INCLUDED ON A 5Vi INCH PC/XT DISKETTE. FULL DOCUMENTATION AND SCHEMATICS ARE ALSO INCLUDED. FOR INFORMATION ON A LOW COST SPEECH SYNTHESIZER SYSTEM FOR THE VISUALLY IMPAIRED. PLEASE SEND FOR FREE PACKET T.M.1. STAND ALONE POWER SUPPLY FOR ABOVE ADD $2.90 SHIPPING 8 HANDLING $19 99 IBM PC, XT COMPATIBLE KEYBOARD IBM, PC, XT COMPATIBLE KEYBOARD CHEAP PRICE EXCELLENT QUALITY COMPUTER MANUFACTURERS EXCESS. BRAND NEW UNITS MANUFACTURED BY HONEYWELL. COfLED CONNECTING CABLE. HAS SAME MAKE AND BREAK CODES AS STANDARD PC, XT KEYBOARD. WORKS FINE WITH CLONES ANC COMPATIBLES. ADJUSTABLE REAR ELEVATION CONTROL (3 LEVEL). ORIGINAL COST IN EXCESS OF 565.00 EACH. *1955 o,3/t475o Add S3,00 Bidi Tor ihlpplng SOCKETS Low PnilD* SOLDER TAIL 6 Pin 14('1.00 BAUD RATE aENERATOR t Pin 14 Rn 16 Pin 16 Pin 20 Pin Z2 Pin 24 Pin 28 Pin 40 Pin 13'l,e0 13/1 .00 13/1 .00 13/1.00 13/1,00 13/1.00 6/1.00 7/1.00 7/1.00 BUY 510 GET 61.00 - FREE CHOICE N516450 16550 ... BH1941 .. 12.00 . 3.0O 1949(WDn3«M-00} 2.D0 COM6115 2.00 INS6250 2,86 MC 14411 S,99 TERMS: (Unless specllieij elsewhere) Add S2.50 postage, we pay balance Orders ovei S50 OD add 85c (of insurance. No CO D. Texas Res. add 8 V c Tax. 90 Day Money Back Guarantee on all items. All items subject to prior sale. Prices sub|ecl to ctiange wittiout notice. Foreign order - US lunds only. We cannot ship to Menico. Countries ottier ttian Canada, add S4.50 shipping and handling. 6/90 RE-SHOPPER a ft AMIGA-Commodore/^MieA^ ^ Chips... Parts... Upgrades 6526 $12.25 6567 $14.95 6581 $11.25 PLA (82S100) $12.95 All 901 Roms $10.95 41256/120 $2.95 A501-512K Ram $99.50 *FatterySuper Agnus $99.50 8362 Denise $39.95 8364 Paula $49.94 8520A $17.95 1.3 Kickstart Rom $27.95 256 X 4/100 $9.50 1 MEG X 1/120 $9.40 ^Includes Chip Puller (many others in stock) Commodore Diagnostician S6.95 prepaid • NEW, POWERFUL • REPAIRABLE C-64 POWER SUPPLY • 13-month warranty • Complete schematic included $23.95 • External fuse — runs cool PLUS • UL Approved UPS • Heavy duty — perfect for "packet radio" • Conservatively rated (cc 1.8 amps • Made by Commodore sub-contractor Amiga Upgrade.New 1 Megabyte 'Fatter AGNUS' Chip 8372 S99.50 with simple step step 10 min. Instructions and chip puller SEND FOR CATALOG ON EXCLUSIVE NEW PRODUCTS THE GRAPEVINE GROUP, INC. 35 Charlotte Drive, Wesley Hills, N.Y. 10977 1-800-292-7445 • (914) 354-4448 FAX (914) 354-6698 Dealer Prices Available Prices Sublect To Change Motorless Motion! Robotics I Engines! Inventions.' Thin Shape Memory Alloy wires, contract like living muscle when electrically activated. Space Wings - Sleek silver wings flap silently using only 5 cm of SMA wire. Assemble this futuristic kit in under an hour. Stands 15 cm high. Perches on your PC or desk lamp. Annoys cats. With printed circuit board, parts, info on SMAs, and complete instructions. Runs on two AA batteries (not included), 3-001 Space Wings Kit $19.95 Send a business size Sitf-Addressed Stamped Envelope for latest catalog. Order Today - Send check or money order (sorry no credit cards). CA orders add 7.25% tax. All orders add $4 P&H ($8 to Canada). MondO'tronics • 2476 Verna Ct. San Leandro, CA 94577 • USA CIRCLE 337 ON FREE INFORMATION CARD 4-Piece Electronics Pliers Kit * U.S. Made -A- Lifetime Guarantee Finest quality alloy steel pliers with color-coded cushion grip handles. Includes 4-1/2" miniature diagonal cjtter, 5-1/2" diagonal cutter, 6-3/4" chain nose viHh cutter, 4-3/4" miniature chain nose and vinyl roll pouch. Charge Visa, MasterCard. American Express or send check or money order. RES>e2 Pliers Kit ... $39.00 We pay the stitpplng charges. JENSeMTODLS INC. 7815 S. 46th St. Phoenix, AZ 85044 < Phone (602) 9684231 • FAX (602) 438-1690 CIRCLE 338 ON FREE INFORMATION CARD Annerican Heart Association ^ THE ULTIMATE PERSONAL DUac 95 UV ERASER 39 Add 3!£ Shipping i Hauling Also Avaiiat)(fl DH.CT 49^ AC wtUi intftrinal 2 - 8 minut* tim«r snd tim« out b««p4r. D1[B 3!;^49*^ Bftfl^ry powsrsHd for IQC cvclofr. IniflmaJ 2-B min. tirn«r, » Optional AC adaptor 7 W^LLinC CO. 4401 S. Juniper • Tempe, AZ 85282 Molded Ptastlc Case • Shirt Pocket Size - Auto Stan - Erases inost EPBOM's/EPLD's in 3 minutes KaiKlles all sizes up to tour at a time • Regulated lamp output for unifaiin erase time Dealer Inquiries welcome. 6 month unconditional guarantee. Order direct or call for dealer near you. (602)838-1277 1-800-338-9813 r Are vou in D EFA U LT On a Student Loan? If you're in default on a guaranteed student loan (FISL, GSL, Stafford, SLS, or PLUS loan), you may be eligible for a special program that lets you pay it back without penalty or collection charges. You must pay your loan in full by August 31, 1990 to take advantage of this special program. For information, call the guarantee agency that holds your loan, or call the U.S. Ctepartment of Education's toll-free number; (800) 333-INFO 36 RE-SHOPPER ALL^^ PLASMA ^•^ Become the Lord of your Galaxy or the Hit of the Party! Length of visible fiasmk fire Add is controlled by your touch. Creates a bizzare and spectacular effect. Available in Star Fire Red, Photon Blue, Nova Purple, and Phasor Green. Please specify color. PFS20 FIRE SABRE (battery not tnduded) $89.50 PFS2K EASY TO BUILD KIT EwwffentSosncs Pmjectl $59.50 Quantity Dsmuflts 10-24 $i5.00 £5-99 $40.00 100+ $35.00 1,000+ Price on Req \pumm wm. yumr Experience the mystifying beauty of PLASMA STIK UGHTING™ Highly Efficient Cold Cathode design uses UL lo volt adapter. fMunns Available in: • Garden Green •Pool Blue •Walkway White Warning Red nv-H3i • Safe, Easy to Install - simply push into ground • Weatherproof, durable construction • Economical to operate - less than 2 watts Basic system includes one STIK LITE and a pwwer adapter capable of driving up to 3 extra "AD-ON's". Buy extra STIK LITE as needed. Specify color(s). STIK Basic System, l Stik Ute with power adapter (or 3 AD-ON's $49.50 EKTRA STIK LITE ADON's, Each $29.50 PRODUCTS IMIMI(SM»S®®M ^m, IM Brightly lit columns of colorful plasma move up and down with the intensity of sounds and music picked up by the • Mounts Anywhere "^^^^ built-in microphone. • 26 Inches Long! • 12VDC/U5VAC Operation • Adjustable Sensitivity • Available in Star Fire Red, Photon Blue, Nova Puiple and Phaser Green (please specify) DPL20 DANCING PLASMA ^.50 DPL2K EASY TO BUILD m $69.50 Discounts 10-24 152.00 25-99 $47.00 10O+ $40,00 1,000+ Pries on Raq 'Decor W mi Mi» Brightly lit columns of colorful neon for enhancing, lighting or decorating. Available in- • Star Fire Red • Photon Blue • Nova Purple • Phasor Green iTM • Mounts Anywhere ■ Lightweight, Durable Actual 26 inches in Length • Special Effects - Strobing • Low Voltage Operation • Simple, Safe DNE10 DECOR NEON $79.50 DNE1K EASY TO BUILD KIT $59.50 Ouantitr Discounts 10-24 $39.00 25-99 $35.00 100+ $30.00 1,000+ Price on Req Most products on this sheet are matte possible through a recently obtained patent for single ended energizing of neon display signs and lighting systems. Ref U.S. Patent #4,742,278. All requests for quantity or dealer discounts are welcome. You may fax us at 603-672-5406. PtTone orders BOO-221-1705 or 603-673-4730 for 24 hour senrice. Call 603-673-6493 for information. FAX ORDERS: 1 '603-672-5406 I PHONE ORDERS: 1-800-221-1705 INFORMATION UNUNITED P.O. Box 716 Amherst, New Hampshire 03031 603-6734730 ORDERS; BOO-221-1705 RE-SHOPPER USE R-E SHOPPER CLASSIFIEDS READ BY MORE THAN 100,000 ELECTRONICS BUYERS AND SELLERS AND TRADERS INSTRUCTION FOR PLACING YOUR AD! HOW TO WRITE YOUR AD TYPE or PRINT your classified ad copy CLEARLY (not in all capitals) using the form below. If you wish to place more than one ad, use a separate sheet for the additional ads (a photocopy of this form works well). Choose a category from the list below and write that category number into the space at the top of the order form. !f you do not specify a category, we will place your ad under Miscellaneous or whatever section we deem most appropriate. We cannot bill for classified ads. Payment in full must accompany your order. We do permit repeat ad or multiple ads in the same issue, but in all cases, full payment must accompany your order. WHAT WE DO The first two words of each ad are set in bold caps at no extra charge. No special positioning, centering, dots, extra space, etc. can be accommodated. RATES Our classified ad rate is 40* per word. Minimum charge is $6.00 per ad per insertion (15 words). Any words that you want set in tiold or caps are 10c each extra. Bold caps are 20C each extra. Indicate bold words by underlining. Words normally written in all caps and accepted abbreviations are not charged as all-caps words. State abbreviations must be Post Office 2- letter abbrevia- tions. A phone number is one word. CONTENT All classified advertising in the R-E Shopper is limited to elec- tronics items only. All ads are subject to the publisher's approval. We reserve the right to reject or edit all ads. DEADLINES Ads received by our closing date will mn in the next issue. For example, ads received by June 11 will appear in the September, 1990 Issue that is mailed on July 10. No cancellations permitted after the closing date. No copy changes can be made after vie have typeset your ad. NO REFUNDS, advertising credit only. No phone orders. AD RATES: 40c per word. AAinimum S6.00. Send your ads with payment to: Radio-Electronics SHOPPER, 500-B Bl-County Blvd. Farmingdale, NY 11735 CATEGORIES too — Antique Electronics 270 — Computer Equipment Wanted ■(30 — Audio- Video- Lasers 300 — Computer Hardware 160 — Business Opportunities 330 — Computer Software 190 — Cable TV 360 — Education 210 — CB-Scanners MO — FAX 240 — Components 420 — Ham Gear For Sale 450 — Ham Gear Wanted 480 — Miscellaneous Electronics For Sale 660 — Satellite Equipment 510 — Miscellaneous Electronics Wanted 690 — Security 540 — Music & Accessories 570 — Plans-Kits-Schematics 600 — Publications 630 — Repairs- Services 710 — Telephone 720 — Test Equipment CLASSIFIED AD COPY ORDER FORM Ad No. 1 — Place this ad in Category # 1- $6,00 5 $6.00 9- $6.00 13 -$6.00 17 -$6.80 21 -$e.40 2S -$10.00 2 -$6.00 3 - $6.00 4 - $6.00 6 - $6.00 7 - $6.00 8 -$6.00 10 - $6.00 11 - $6.00 12 - $6.00 14 - $6.00 15 - $6.00 16 - $6.40 18 - $7.20 19 - $7.60 20 - $B.0O 22 - se.eo 23 - $9.20 24 - $9.60 26 - $10.40 1 Payment $ _ 27 - $10,80 nndnsBrf 28 -$11.20 [ ] Check [ ] MasterCharge [ j Visa ($15.00 minimum credit card order) Name 29 - $11,60 30 - $12.00 31 - $12.40 32 - $12.80 33 -$12.00 34 -$13.60 35 -$14.00 36 -$14.40 37 -$14.80 36 -$15.20 39 - $15.60 40 -$16.00 Ad No 1 — Total words All Caps words . Bold words Bold Cap words . -x.40perword = $, -X .10 per word = $ . .X .lOper word = $ , .x.20perword=$ . TOTAL COST OF AD No. 1 $ Card #. Expiration Date / . Signature . Phone , Address , , City State Zip , i RE-SHOPPER CABLE TV BLOWOUT Jerrold 450 Combo DRZ 3 QIC With new remote, 68 channel original equipment automatic fine tuning WE WILL MEET OR BEAT ANY ADVERTISED PRICE IN THIS MAGAZINEl PLEASE PRIMT: J Ciahlaf»Cli»ek J Money Qrdtr -ICOD Quantity Hem Name: Address: City/Stalefflp: Price B8. Total OROeRSONLY: 1-800-622-9022 FREE CATALOG* INFO' (203) 975-7543 10 AM 5:30 PM EASTERN TtME »*0e0hhiECTiCuT5>'LES II n nirtitiB ^IwH el UNIVgR^Al. VIEW IQ OB'i'Ajd in^ a»t W*ri%Ai^ C^nW wnd It MnH nD[ BI143 AAf rjOTfurff V liV'v'du'Ai fi dang aa WAIVER. 1. the undersigned, am a cons«ntiirig sdun of al l^ast 2t year? ol ag#, and lu!ly uncfsr^tand (hal cwnershtp of a caWe decoder does not grve Ihe owner ol !he decode [he nghv lo decode or view o'emFum cable channels w»thou! proper authwiratioft 1roim iheir local cable company, and hereby declare uride:! penally a\ perjury that a>ll pnixFucTs purchased, at any time, will only b* used Ofi cable TV syiterns with proper autlwrizalion tfom ^ocal olficiais or cable cornpany officers m accordance with all appticable feda^al and slate laws Federal and vanous &late laws pjcvide far sub^laniial cnmtnal ^nd C^vil p«na1|ies Ioit Linaulhonzed use. Signature Date RE-SHOPPER FREE CATALOG Loaded With Satellite TV Products At Discount Prices • Complete Systems • Upgrades • 2ft to 24ft Dishes • Parts • Accessories • IUIa|or Brands • Factory Fresh • USA Warranty • Fast Delivery Satellite WORLD SATELLITE TV AND SCRAMBLING METHODS "The Technicians' Handbook' This thorough text is a must-buy [or technicians, satellite professionals and curious do-it-yourselfers. The design, operatitxi and repair of sateilile anten- nas, feeds, LNBs, receivers and modulators are ex- examined in detail. An in-depth study of scrarnbllng methods and broadcast formats induding the VideoOpher II, Oak Orion, FilmNet, Sky Channel, EuroCypher, D2 MAC, BSB and Teledub Payview III. Circuit aind bbck diagrams of all corriponents are presented and dearly exa/nined throughout the handbook. This informatiofi is a prelude to the chapters on troubleshooting and setting up a test bench. This expert guidance on testing, servidng and timing is complimented by a wealth of detailed illustrations. J44) pi^ti, 8 111 1 1B M av*r zoo photos, dlagrtms, wiring uhttnttics and 16 tiblis t *pp*ndici> / iiid*x Ofdtr #211 S&K 14 (U.S.) $39,9S THE SKYVISION DO-IT-YOURSELF INSTALLATION VIDEO "Now You Can Watch It Being Done' installing or Tuning up" your satellite system made simple. From start to finish, the Sky vision Do-Il-Vourseif Installation Video is a step-by-step video ^at will help you set-up your systems in no time flat. Ifs tike having our trained technicians right at your site helping you wilh every step. Ord*r iSKIO VHS ...^H 13 (U.S) t33.9S Ord*rfSK11 B«ta S&N$3(U.S) t33.9S TV Anywhere TUNE YOUR DISH TO ITS MAXIMUM! 'With The Pico Signal Meter" A must for ^e serious dealer or satellite system owner. Saves time, frustration and money. Use when instailine a new system, moving your dish, re-alignment of a dish that has been moved by wind, frost fwaves etc., gets you right on the satellite belt for ihe best possible picturesi The PP-1450 Pico PeaKer is a super sensitive signal meter used for antenna aiming, focusing, peaking and polarity alignment. The multi-purpose Peaker can t>e used on any receiver system with block down-convened frequences between 70 and 1 500 MHz. [Does not work with older single conversion receivers - Ask foe Bulz-I-Meter) The Peaker comes in an attractive case with r>eck strap. Ordtr IPP-14S0 . SiH U (U.S.) ....-»9.95 Cptional jurrp cabb kit. Conroos Peaker to LN8 (Kit irx:ludes 2ei, 12' coax cables w/ spiles r). OrtJer IC212 SIH U $7,95 IRDs / RECEIVERS / SYSTEMS "Save $$$ on Pach:ages" System package Includes: ORBITRON lO toot mesh dish, BOde^jree LNB. IB' Jack Arm, Feed- horn and Becesver/tRD olyour choice, plus a FREE detailed irrslallation Video. IflCWBCeiver System (Receiver) $219 (ReceivaiJ (IHD) (IRD) (slave recv.) tlHD) um (IRDj (IHD) (ReceivBr) (fiecoiveO tIRD) (IRD) (IRD) (Slave recv.) UNIDEN UST2200 UWIDEN UST9000 UNIDEN UST7700 UNII3EN UST9900 UNIDEN UST4200 UNIDEN UST4400 UNIDEN UST4800 HTSV HTS VIII Plus J-TTS X DRAKE ESR324b DRAKE ESR924i DRAKE ESR1024 DRAKE ESR1224 DRAKE ESR1424 ECHOSTAR 3000 ECHOSTAR 4000 $449 $899 $1019 $679 $909 $1539 $1049 $1229 $1419 $239 $599 $909 $1039 $1209 $729 $999 $1449 $1569 $1459 $2069 $1599 $1779 $1969 $1149 $1459 $1589 $1759 $1399 (IRD) $949 Just a partial listing of hundreds of products listed in the Skyvison catalog. Ask for your's today! 2048 College Way Fergus Fslle, MN S6537 - Toll Free 800-334-6455 Mail in coupon or call Toll FREE today lor the SKYVISION Satellite TV Product Catatag. Delivered free to your mail box in U.S. and its holdings. * International requests add $8.00 to cover shipping and handling. Send Sicyvislon Satellite TV Products Catalog Phon e ( ) D! Name. State 2ip_ Install A System, Upgrade or Repair Yourself And Save $$$$ 40 RE-SHOPPER CIRCl-E 350 ON FREE IMFORMATION CARD FIG. 3— THE MECHANICAL ASSEMBLY of the Lawn Ranger. f nee I u^aw^lA^fi h-^ JM7 J1-1B '"xr* SI -a S2-a S3-a S4-a SS-a S&a S7-a ""I <^ ^M^ <^ ffch ^ f fcPi f^ S15-a S14-aS13-s S12-a S11-a SlO-a S9-a (:[) Se-a J1-19 TJ^^V^V ^^V V- sib S2-b S3-ti S4-b SS-ti S&-b S7-b S8-b J1-1 J1-2 J1-3 J1-4 J1-S ^\|/ \[/ \1/ \|/ \|/ \J/ \i/\[^ij J1-6 J1-7 J1-S J1-15 JM4 J1-13 J1-12 J1-11 J1-10 J1-9 ^V^J I ^ .SEWSORS, P 1-15 ^ ) o w // r-| ( d FIG. 4— WIRE THE GRASS SENSORS as shown here. Chassis wiring Wire the chassis as shown in Fig. 5. Use 18-gauge stranded wire for the high-current cut- ting- and drive-motor connec- tions. Secure the cable harness with tie wraps and secure the ca- ble harness to the Lawn Ranger's chassis. Make sure all external cables from the motors, elec- tronic control panel, bumper switch, and grass sensors are connected properly. Control-system test Remove all input power and in- sert the power board into J21 on the motherboard. Repeat the test procedure that was Just de- scribed, except measure the DC supply voltages at edge connector J23 and J22 on the mother- board. The supply voltages should agree with the values in- dicated on the CPU and motor- controller board schematics (re- fer to Radio -Electronics. June and July 1990). If the values are correct, remove the input power and plug the CPU board in edge- connector J23, Reapply the +24- volt input power and recheck the voltage levels. If all is well, per- form the digital-board check-out procedure outlined in the June CO o z o EC lU _1 Ui g < DC PARTS LIST— POWER BOARD All resistors are Vs-wati, 5%, un- less otherwise indicated. R1-R10, R13-R15, R17, R18, R20-R28, R45~-R49— not used R11, R44. R50— 3300 ohms R1 2— 680,000 Ohms, 6-pln, V'j-watt, SIP resistor network R16, R19, R32, R43— 0.01 ohm, 5 watts R29— 150.000 ohms R30, R31, R34, R35— 270,000 ohms R33, R36— 1 megohm R3 7— 147,000 Ohms, V4-watt. 1% R38— 10,000 ohms, potentiometer R39— 82,000 ohms R40— 100,000 ohms R41— 27,000 ohms R42— 22,000 ohms R51~R54— 560,000 ohms Capacitors C1-C5, C7-C13, 016, 017— not used C6— 1000 |iR 35 volts, axial electrolytic 014, 015, 023-026—0.1 \i.F. 50 volts CI 8, 021—100 jjlR 50 volts, radial electroiyttc 019, 020—100 |xR 16 volts, radial electrolytic 022— 220 V.F, 16 volts, radial electrolytic Semiconductors 101, 102— not used 103— LF412N op amp D1, D2, D11-D13, D30. D31— not used D3, D4, D16, D17, D20-D24, D33-D38— 1N4001 diode D5, D14, D18, Dt9, D32— 1N4148 diode D6, D15— 1N5402 diode D7-D10— 1N5256B 30-vo!t Zener diode D25-D29— 1N4740 10-volt Zener diode Q1,Q2. Q12— notused Q3-Q10, Q13, Q14— IRFZ42 MOSFET Q11, Q15, Q16— 293904 NPN transistor Other components J11 — terminal strip RY1— T90N1D12-24 relay (Potter Brumfield) RY2— 68P-111P-US-DC24 relay (Omron) F1— SAG 30-amp fast-blow fuse F2— 2AG 0.5-amp fast-blow fuse MODI— Model DC2-2-24/12, ± 12- volt DO converter (Power General) M0D2— Model DC2-2-24/15, ± 15- volt DC converter (Power General) MODI— Model 710, 5-volt DO con- verter (Power General) Miscellaneous: 3AG fuse holder, 2AG fuse holder, solder posts for the "E" terminals, 18-gauge solid insulated wire, 18-gauge stranded insulated wire, solder, etc, Note: The following equipment can be purchased from Tech- nical Solutions, Inc., P.O. Box 284. Damascus. MD 20872 (301-253-4933): etched and drilled PC boards for CPU Board, Motor Controller Board, Power Board, and Motherboard, S39 each: programmed EPROM, $39: grass sensors, $8.99 each; hand-held manual controller kit, $39; full kit for CPU Board. $129 (PC board, EPROM, all parts); full kit for Motor Controller Board, $169 (PC board and all parts); full kit for Motherboard, $69 (PC board and all parts); Power Board kit (PC board, and all parts except DC/DC convert- ers), $149; Detailed drawing package, $79; Lawn Ranger demo videotape and information package, $19; complete elec- tronic kit with everything men- tioned above, $777. Please add $8.00 for S/H for all orders. Mary- land residents add sales tax. 56 issue while the boards are plugged into the motherboard. Now plug the motor-controller board into J22 on the mother- board. Also, plug the grass-sen- sor connector (Jl) into the motor- controller board. Reapply the -l-24-volt input power to the power board. If you have an oscilloscope, ver- ify that a 5-volt 10-kHz square wave is found at the following points; J22-34, Jl-1 through Jl-15, and J22-2 through J22-16. The square wave is a gat- ing pulse created by the CPU board which is used to turn the grass sensors on and off. The gat- ing technique is used in order to conserve battery power and ex- tend the life of the grass sensors. If you don't have a scope. Use an AC voltmeter to read the voltage levels at those points. The square wave should create a reading of approximately 4.5-volts AC. If the square wave is not there, you should read volts on the AC volt- meter Now it is time to check the Pulse Width Modulator (PWM) circuitry. Plug the hand-held con- troller into J4 on the motor-con- troller board. Temporarily Jumper J22-40 to ground. Tlirn the steering control knob ( the po- tentiometer on the hand-held controller) counterclockwise un- til you see a 30-volt square wave at J22-26 (l, rev), JlI-7 (i, motor - ), J22-27 ronze or red plex- iglass, mounting hardware, hookup wire 62 . + 12V SENQERq TD 2-DIGIT DlSPLftY FIG. 12— OIL-PRESSURE GAUGE parts- placement. OIL-PRESSURE GAUGE All resistors are V4-watt, 5%, un- less otherwise indicated. R1^70 Ohms R2-R8, RIO, R12-R16— not used R9— 100,000 ohms R11— 10,000 ohms, PC-mounted trimmer potentiometer R1 7— 50.000 ohms, PC-mounted trimmer potentiometer Capacitors CI— 47 |xF, 25 volts, electrolytic C2, C3, C4— 10 ^F, 35 volts, elec- trolytic 05 — not used C6-^.33 liF, 50 volts, stacked film Semiconductors IC1— LM340T-5, 5-volt regulator 102— CA3136E, A'D converter D1, D2—1N4002 diode Miscellaneous: 43B21 main PC board, 15G5 oil-pressure sender, 2- digit display board, in-line luse holder, 1-amp fuse, four 6-32 x 0.625" standoffs, eight Vis-inch #6 screws, bronze or red plexiglass, mounting hardwfare, hookup v/ire The main boards are now ready to be connected to the display boards. The first step is to place the four standoffs tietween the boards and secure them with eight Yie-inch #6 screws. Assem- ble the boards with the foil side of the display board facing the com- ponent side of the main board. The holes for the board-to-board connecting wire should line up on the same edge. After the two boards are secured to each other, lay the assembly face down and begin inserting pieces of bare wire or scraps of component leads through the holes in the main board and down into the respective holes in the display board. After a few wires have been inserted, solder the connec- tions. Continue until all nine wires have been installed. The temperature probe for the miscellaneous temperature gauge is constructed from the 1N4148 diode, a lO-foot length of coax cable, and a male and female crimp-on connector On one end SENDER, 4, i- TO 3-DIGIT OlSPLAV FIG. 13— WATER-TEMPERATURE gauge parts placement. WATER-TEMPERATURE GAUGE All resistors are Vi-watt, 5%, un- less otherwise indicated. R1— 100 ohms, '/2-watt R2^t30,000 ohms R3, R7— 10,000 Ohms, PO-mounted trimmer potentiometer R4, R8— 22,000 ohms R5, R9. R11-R16— not used R6— 470,000 Ohms RIO— 2200 Ohms R17— 50,000 ohms, PC-mounted trimmer potentiometer Capacitors C1— 47 (J.F, 25 volts, electroiytic C2, C5— 10 iiF, 35 volts, electroiytic C3, 04— not used 06-^.33 jxF, 50 volts, stacked film Semiconductors D1. D2—1N4002 diode 101— LM340T-5, 5-volt regulator 102— OA3136E, AD converter Miscellaneous: 43B21 main PC board, 14G11 water-temperature sender, 3-digit display board, in- line fuse holder, 1-amp fuse, four 6-32 X 0.625" standoffs, eight Vw- inch #6 screws, bronze or red plex- iglass, mounting hardware, hookup wire. in 3-DlBlT DISPLAV FIG. 14— MISCELLANEOUS temperature gauge parts placement. MISCELLANEOUS TEMPERATURE GAUGE All resistors are Vo-watt, 5%, un- less otherwise indicated. R1-R4, R9, RIO, R15, R16— not used R5— 2200 ohms R6--6800 Ohms R7 — 1000 ohms, PC -mounted trim- mer potentiometer R8— 470 ohms R11— 10,000 ohms, PC-mounted trimmer potentiometer R1 2— 10,000 ohms R13— 1000 ohms R14— 220 ohms R17— 50,000 ohms, PC-mounted trimmer potentiometer Capacitors C1^7 fxF, 25 volts, electrolytic C2, C5— 10 11.F, 35 volts, electrolytic 03, C4— not used 06—0.33 jaF, 50 volts, stacked film Semiconductors !C1— LM340T-5, 5-volt regulator IC2— CA3162E, A/D converter D1, D2—1N4002 diode Miscellaneous: 43B21 main PC board, 1N4148 diode for tempera- ture probe, 3-digit display board, coax cable, in-line fuse holder, 1- amp fuse, four 6-32 x 0.625" standoffs, eight yis-inch #6 screws, bronze or red plexiglass, mounting hardware, hookup wire. of the coax cable, strip off about %-inch of the outer insulation, unbraid the outer conductor, and twist toward one side. Next, strip about '/i-lnch of the cables inner insulation. Position the 1N4148 diode so that the band, or cathode, is touching the outer conductor of CO m S U3 m -.1 c 6S the coax cable. The diode will lay right against the inner-conduc- tor insulation. Very carefully sol- der both sides of the diode, the cathode side to the outer conduc- tor and the anode side to the in- ner conductor. After clipping the excess lead length, coat the diode and exposed wires with a good quality epoxy or sealer. Apply sev- eral coats to ensure a good seal. Only the end of the cable with the diode is coated. On the other end of the cable, strip and separate the inner and outer conductors. Crimp the male terminal to the center conductor and the female terminal to the shield. The solid-state vacuum sensor is mounted to the vacuum gauge by first removing the two screws near 1C3 that hold the main board to the standoffs. Place the sensor bracket on the back side of the main board and align the holes on the two tabs with the board mounting holes and rein- sert the two screws (see Fig. 17). Next, insert the sensor leads into the main board with the lettering on the sensor body facing away from the bracket. Insert the re- maining hardware and tighten the sensor to the bracket. Do not overtighten the mounting screws as you damage the sensor It is a good idea to only hand tighten the screws and apply a small drop of glue to keep them from coming loose. Very carefully solder the leads of the sensor to the board, working from the back side of the board. Be careful not to melt the case of the sensor with the solder- ing iron. Calibration After the gauges are completely assembled, turn all the calibra- tion potentiometers to the center of their rotation. Next, connect each gauge to a 12-volt DC power supply or battery. At this point. all the display digits should light as should the LED light bar. The cEilibration process for all of the digital gauges begins with zeroing the AT) converter. To do g that, pins 10 and 11 of the z CA3162E A/D converter must be § shorted together. Use a small Q screwdriver or jumper wire. Once y connected, the display should ^ now read zero or very close to it. Q Adjust the zero calibration poten- g tiometer (see each schematic for + 12V SENDER I CI D1 d;>»* qpp cfp y fll^ I 1 t 1 — ■ — ■ 1 ' « (PI ' il , R16 ma HM 4m V ^ ij ^ ■ & TO 2-DIGIT DISPLAY FIG. 15— PARTS-PLACEMENT DIAGRAM for the fuel gauge. FUEL GAUGE All resistors are yj-watt, 5%, un- less otherwise indicated. RI— 470 ohms R2, R5. RIO, R12, R14, R15, R16— 100,000 Ohms R3— 33,000 ohms R4— 47,000 Ohms R6 — 1 .8 megohms R7, R19— 100.000 ohms, PC- mounted trimmer potentiometer R8— 10,000 ohms, PC-mounled trimmer potentiometer R9— 200.000 ohms, PC-mounted trimmer potentiometer R11— 2700 ohms R13— 8200 Ohms R17— 22,000 ohms R18— 1000 ohms R20— 470,000 ohms R21— 50,000 ohms, PC-mounted trimmer potentiometer R22— -2200 ohms Capacitors CI — 47 ^l.F, 25 volts, electrolytic C2, C3— 10 ^xF. 35 volts, electrolytic C4— 0.33 (j,F, 50 volts. Stacked film Semiconductors IC1— LM340T5, 5-vott regulator IC2 — LM324, quad op-amp IC3— CA3162E, AJD converter D1,D2—1N4002 diode Miscellaneous: 43B20 main PC board, 2-digit display board, 0.1" 3- conductor header, 2-conductor jumper, in-line fuse holder, i-amp fuse, four 6-32 x 0.625" standoffs, eight yt6-inch #6 screws, bronze or red plexiglass, mounting hardware, hookup wire. exact potentiometer number) so that the display reads "000" or "00," Then remove the jumper. The voltage gauge is calibrated by connecting a good quality bench voltmeter across the power supply that is used to power the gauge. Carefully adjust Rll, the gain adjust potentiometer, so the reading is the same as the read- ing on your bench voltmeter. The calibration process for the oil- pressure gauge requires con- necting a precision 47-ohm re- sistor to the sensor lead and + 1ZV O 1C3 •m^ D2 CI + n t * c'l L-jEr;] RI , , ^ r rb] [rb r IC2 rSro "b"'' r izT 1 7 d" Hi u NK Sf^ ^^^ n1^ Nl/' Sk\t^^ TO 2-DIGtT DISPLAY FIG. 16— PARTS-PLACEMENT DIAGRAM FOR THE vacuum gauge. VACUUM GAUGE All resistors are y4-watt, 5%, un- less otherwise indicated. RI, R2— 10,000 ohms R3, R8— 100,000 ohms R4— 22,000 ohms R5— 1000 ohms R6~-680,000 ohms R7, RIO— 200,000 ohms PC mounted trimmer potentiometer R9— 82,000 ohms R11— 50,000 ohms PC mounted trimmer potentiometer R12— 2200 ohms Capacitors CI —47 M-F, 25 volts, electrolytic C2, C3— 10 fiF 35 volts, electrolytic C4— 0.33 jjlF 50 volts, stacked film Semiconductors IC1— Sensym SX30DN vacuum sen- sor (Dakota Digital #69G18 in- cludes mounting bracket) IC2— LIVI324, quad op-amp IC3— LI^340T-5, 5-volt regulator IC4— CA3162E, A'D converter D1, D2—1N4002 diode Miscellaneous: 43B17 main PC board. 2-digit display board, in-line fuse holder, 1-amp fuse, four 6-32 X 0.625" standoffs, eight Vie-lnch #6 screws, bronze or red plex- iglass, mounting hardware, hookup wire. 64 carefully adjusting Rll so the reading is at "47," Actually, any resistor between 33 and 91 ohms can be used to calibrate the unit. Just set the display to coincide with the value of the resistor. The water- temperature gauge is calibrated by connecting the sending unit and adjusting for freezing and boiling tempera- tures. First, prepare a bowl of water with several ice cubes in it, and a pot of boiling water. Place the sending unit in the boiling water with its base submerged in the water and the terminal above the water line. After waiting about a minute for the sending unit to stabilize, adjust the "high adjust" potentiometer (R7) for a reading of "212" on the display. Next, place the sending unit in the ice water using the same pre- cautions not to let the center ter- minal come in contact with the water. Wait a minute for the send- ing unit to stabilize and adjust the "low adjust" potentiometer (R3) for a reading of "032" on the display. Repeat the high- and low- adjustment procedures until a good balance has been reached. To calibrate the fuel gauge, you must determine the empty and full resistance of your vehicle's sender For most Fords, its 73 ohms empty to 10 ohms full. GM vehicles run from ohms empty to 90 ohms full, and AMC, ma- rine, and most aftermarkel send- ers use the scale of 244 ohms full to 33 ohms empty. The calibra- tion range of our fuel gauge will easily accept the input from vir- tually any brand of sending unit. Obtain two resistor values that are very close to the empty and full resistances of the sending unit that will be used. If your sys- tem requires you to use the "A" circuit, you will begin calibrating the fuel gauge by first turning R9 fully counterclockwise. Be sure the jumper is in the "A" position. With the "empty" resistance con- nected to the lead wire , adjust R7 for a reading between "00" and "05." Because the gauge has a large RC circuit for averaging, al- low plenty of time for the reading to settle. Next, connect the "full" resistance and adjust R9 for a reading between "95" and "99." It is usually better to have some headroom to avoid over-range and under-range conditions due to sending-unit tolerance. After P0RT2(P2[ BRACKET n SCREW 6-32 X .2ft" j^PORTKPll SENSOP LETTERING SCREW 6-32 X .625 "tCl (SENSOR) MAIN BOARD t ^V COMPONENT SIDE lb DISPUV BOARD .^ FIG. 17— PLACE THE SENSOR BRACKET on the back side ol the main board and align the holes on the two tabs with the board mounting holes. the empty and full settings are adjusted, repeat the two steps until a good balance has been reached. If the "B" circuit is being used, begin the procedure by turning R19 fully clockwise. Connect the "empty" resistance and adjust R8 for a reading of "00" to "05" on the display. Reconnect to the "full" resistance and adjust R19 for a reading between "95" and "99." Repeat the two steps until a good balance has be obtained. The calibration procedures for the miscellaneous temperature gauge are almost identical to the water-temperature gauge. Pre- pare a bow! of water wi th several ice cubes and a pot of boiling water. Place the temperature pro- be in the boiling water, wait 30 seconds for it to stabilize, and ad- just Rll for a reading of "212" on the display. Next, place the send- ing unit in the ice water Wait an- other 30 seconds for the sending unit to stabilize, and adjust the "low adjust" potentiometer (R7) for a reading of "032" on the dis- play. Repeat the high- and low- adjustment procedures until a good balance has been reached. The calibration process for the vacuum gauge begins by turning RIO fully clockwise and adjusting R7 for a reading of "00" on the display. That zeros the offset of the pressure/ vacuum sending unit. Next, connect a piece of %4- inch vacuum line to P2 (port 2) on the sending unit. The other end must go to an accurate vac- uum source that you will use as a standard for full-scale calibration of the vacuum gauge. The vac- uum source can be a hand-held 3-DIGIT DISPLAY BOARD Ail resistors are y4-watt, 5%, un< less otherwise indicated. R1, R2— 220 ohms R3— 220 ohms (voltmeter only) Semiconductors 1C1— CA3161E, Display driver D1SP1-DISP3— 0.43" 7-segment C.A. LED display {Panasonic LN514RA) Q1-Q3~-2N3906 PNP transistor LED1— 5- X 15-mm LED, {Pan- asonic LN0202RP) 2-DIGIT DJSPLAY BOARD All resistors are V^t-watt, 5%, un- less otherwise indicated. R1, R2— 220 Ohms Semiconductors ICI— CA3161E, display driver DiSPI, DISP2— 0.43" 7-segment C.A, LED display (Panasonic LN514RA) Q1, Q2— 2N3906 PNP transistor LED1— 5- X 15-mm LED, (Pan- asonic LN0202RP) Note: The following items are available from Dakota Digital, 11301 Kuhle Drive, Sioux Falls, SO 57107 (605) 332-6513: a PC- board set for each gauge (in- cludes main PC board and dis- play board) is $6.95. A parts kit for each gauge (includes PC boards, components, and man- ual) Is $29.95. Each gauge as- sembled and tested is $39.95. Stock numbers are as follows: voltage-gauge kit #2005-KIT, as- sembled and tested #3005- UNtT; oil-pressure gauge kit #2006-KIT, assembled and test- ed #3006-UNIT (order oil-pres- sure sender separately); water- temperature gauge kit #2007- KIT, assembled and tested #3007-UNIT (order water-tem- perature sender separately); miscellaneous temperature gauge kit #2008-KIT, assembled and tested #3008-UN1T; fuel- gauge kit #2Q09-KIT, assembled and tested #3009-UNIT; vac- uum-gauge kit #2010-KIT, as- sembled and tested #3010-UNIT (order vacuum sensor sepa- rately). Oil-pressure sender (#15G5), $15.50; water-tempera- ture sender (#14G11), $5.50; vac- uum sensor (#69G18), $19.95; RCA CA3161E driver (#69016), $1.95; RCA CA3162 A/D convert- er {#69015), $7.95, All orders add 4% shipping and handling {$1.50 minimum). Visa and Mas- tercard accepted. I .• ir. rr ■c n S a rr 6! w o z o □: H O LU _l Lit 6 D < vacuum pump that has an accu- rate dial gauge, or you can con- nect the vacuum gauge and an automotive tune-up vacuum gauge to a running engine and use Its reading as your standard. Once a known amount of vac- uum is connected to the vacuum gauge, adjust RIO for a full-scale reading. Installation A good enclosure will protect the units from shock, dirt, and shorting. The enclosure must also have a front panel that will enhance the viewing of the dis- plays. That is especially impor- tant for bright days, where bare LED displays can be very difficult to read. The digital gauges can be mounted by the same bolts that hold the two boards together. That allows the point of mount- ing to be from the front or back of the unit. For rear mounting, the screws that hold the main board to the spacers are removed. From here, additional spacers are used to mount the unit to a panel lo- cated behind the digital gauge. The length of the spacers will de- pend on how far the mounting panel is from the front panel. The unit can also be mounted directly to the front panel by removing the screws holding the display board to the spacers. Here again, additional spacers will be used to keep the unit away from the front panel and provide a secure mounting. If mounted from the front panel, use an attractive screw that will enhance the look of the front panel. Hex-head screws, Allen screws, or Torx screws can be used. As with any type of enclosure, you will also need to drill or cut vent holes to allow heat to escape. For the front panel, bronze or smoked plexiglass is recom- mended. That material is not only durable, but it will also keep outside light from shining into the display area and allow the LED's to shine through, thus creating a more visible and reada- ble display. Red filter plexiglass will also work well as long as only red LED's are used. The front panel should be masked to allow only the LEDs and annunciator to show, thus hiding the rest of the display board. Masking can be done by taping over the area j S^^tf f* 1 '3/16 INCHES »-| VOLTS, OIL, WATER, AND MISC. TEMP. H ^fU^^H* -1"/ibINCHES- 2-DIGIT DISPLAY SOLDER SIDE. t^^»^ SIDE o e J e e [* 1 1 1 Mt • • • • ^B -1"/i6 INCHES - VACUUM GAUGE FOIL PATTERN. |_ — 43B16 |-* 1"/is INCHES —^ 2-DIGIT DISPLAY COMPONENT SIDE. \* 1'3/i6 INCHES ^ SOLDER SIDE OF THE FUEL GAUGE. 4-3B20 ^^9 COMP f Oi SIDE ol ooe^-o »>j» ^0 a o o tt a a e •••««oato ' 3-DIGIT DISPLAY SOLDER SIDE. r _ _ n -1"/i6 INCHES J 43B:5 -l^/ia 1NCHES- I COMPONENT SIDE OF THE FUEL GAUGE. 3-DIGIT DISPLAY COMPONENT SIDE. 66 where the displays will be located and painting the uncovered area black on the back side. Both the oil-pressure gauge and the water-temperature gauge require sending units to be mounted to the engine. The oil- pressure sending unit mounts directly to the block of the en- gine. Its '/s-inch pipe thread fits GM motors directly while Ford motors, along with some other manufacturers using '/j-inch thread, will require a 'A- to Vs- inch adapter. The water- tempera- ture sending unit is made to mount directly to the block or water pump of a Ford motor using standard %-inch pipe thread. GM motors will require a 1/2- to %-inch adapter. Should your application be somewhat different, adapters and fittings can be obtained from your local hardware or automotive store. You may also wish to keep your original gauge or idiot light Ihat came factory with your car. That can be done in one of two ways. A "T" fitting can be used to mount both the original sender and the new sender. Otherwise you have to find another location that is occupied by a plug that can be replaced with the sending unit. That lets you keep the factory dashboard functions Intact. When connecting the fuel gauge to the fuel sender, the easi- est method is to find the factory wiring harness connection that iTjns back to the fuel tank. A sec- ond option is to run a new wire. The original fuel gauge cannot be connected to the same sender that the new digital fuel gauge is using. The two will interfere with each others readings. When connecting any of the gauges to the motor or fuel tank, be sure that the sender has a good connection to chassis ground. Failure to properly ground the gauge or the sender will result in erratic or incorrect readings. The temperature probe for the miscellaneous temperature gauge can be mounted in one of several ways. When monitoring air temperature, inside or out. the probe should be placed in an area where a good average tem- perature exists. Inside, that may be under the dash, away from any heating or coohng vents and out of any sunlight. Outside, un- der the front grill area of the car win provide the most accurate point as it is out of the sun and not affected too much by engine heat. If the goal Is to measure the temperature of the transmission fiuid, engine oil, differential, or coolant, mount the sensor in a manner that maintains good thermal contact to the outer plate of the item being monitored. Heat sink compound should also be used to ensure good thermal contact. For example, when monitoring oil temperature, mount the sensor to the bottom, back side of the oil pan, where there will be very little air move- ment to cool the sensor. Remove one of the ol! pan bolts and manufacture a bracket that will hold the probe to the oil pan. This can be a simple piece of alu- minum or thin steel cut in such a way so when the oil pan bolt is inserted through the bracket and into the block, the sensor will be lightly compressed between the bracket and the oil pan. Do not make it too tight, as excessive pressure on the 1N4148 diode will break its glass housing. You may want to hold the sensor by the cable near the diode to be safe. Apply heat sink compound to the sensor and the oil pan where con- tact Is to be made. Be sure the oil pan is free of dirt. Then route the coax cable up through the fire- wall to the location of the gauge. The vacuum gauge is con- nected to the intake manifold via y64-inch vacuum hose. Run the hose through a location in the firewall and to the intake man- ifold, or vacuum "T" usually lo- cated near the rear of the engine compartment. Connect the vac- uum hose to P2 (port 2) on the sending unit. Once a suitable panel or en- closure has been constructed, and the gauges mounted to It. In- stall the assembly into the vehicle and connect the power to a source that is on only when the ignition key is in the "on" posi- tion. Be sure to secure any hook- up wires so Uiey will not present a hazard to you or your vehicle. 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Assembte, Test and Repair 'Efeclroncs' TO ORDER, CALL 1 800 482-44401 In MA (617) 821-1870 Prices gcad unljl Odober 3t , 1 990. IJ HUB Material Company 33 Sprfngdate Avenue Canton, MA D2021 CIRCLE 188 ON FREE INFORMATION CARD jf UCTION TO CROWAVE CH^OLOGY LAST MpNTil. WE EXAMINEDn! basic concepts of the electromaj netic spectrum, some basic pk- rametfrs of electromagnetic V waves (such as amphtude, fre- quency, period, and wavelength), and same early methods of RF generation, including the spark- gap generator, and the Barkliausen-Kurz Oscillator or BKO. This month, well examine some early m icrowave RF sources in greater depth, totiyand appre- ciate the problems faced by early designers. p In the early days of radio, the term "microwave" meant any- thing above about 100 MHz. The region above modern CB was usually called "UHF." which an early textbook referred tojokingly as "unbeUevably high frequen- Learn about early RF oscillators in our continuing series on microwave circuits ciesv'" Man< ■ecent European re- ceivers mark the FM band J. (88-108 MHz) with a "U," after >; the German "ultra kurz welle • (ultra-short waves). Such earl, '''■tlesignations were indicative of "the problems of generating R?" V,power at such frequencies be- ^cause of device lin-^tations. One of the earliest problems in- hibiting full use of the RF spec- trum was the inability to gener- ate enough RF power at I'requen- cies of value. For many years generating RF signals at useful power levels, was limited to the Medium-Firequeucy (MF) band. Various problems limited devices then in common use. But from 1920—45. advantage was taken of inherent limitations of vacuum tubes to enable the generation of RF power at higher fre- quencies. The definition of what constitutes high frequen- cies has varied according to the difficulty of gener- ating RF power at those ranges. Until the ear- ly- 19208. when hams opened the HF shortwave region (3-30 MHz), com- mercial radio used the MF range with: X<200 m/cyc, or; /"««•• AM radio is seeing hard times. MOLLY WOULD CRY OUT. "NO, NO. McGee — -not the front closet!" But Fibber McGee would open the door anyway, and there 'd fol- low several seconds of crashes, bangs, thuimps, and thuds as Fibber's famous overstuffed clos- et emptied out. The radio au- dience loved that, as well as the show and its characters. Fibber McGee and Molly were part of the "Golden Age" of radio in the 1930s. 1940s, and early 1950's. when amplitude modula- tion (AM) was king, and Jack Armstrong, Gangbusters, Gab real Heater, the Lux Radio Theater, Edward R, Murrow, and hundreds of other shows and per- sonalities ruled the airways. It was even bigger then than TV is now, because there was really no competition except movies and newspapers. Now, those days are gone and AM is seeing hard times. The present AM is a far ciy from a decade ago. The trouble with AM Surprisingly, AM's problems are only partially due to TV. When TV skyrocketed in the 1950s, AM radio actually prospered, despite a period when it took some blows. Once the Top 40 arose, with repetitive song cycles, ener- getic disc jockeys, time, tempera- ture, and contests, AM found its fortLmes again. Actually, most of AM's troubles come from fre- quency modulation (FM) compe- tition. AM and FM may both be radio, but there are some impor- tant differences in the way infor- mation is transmitted. Both AM and FM transmitters radiate "carrier" wave RF, modu- lated to contain transmitted in- formation. In AM. the carrier wave amplitude is proportional to the audio amplitude, but the carrier fvGquency is constant. Figure 1 shows the components of an amplitude modulated wave- form; (a) is the carrier RF signal, [b] is the audio-modulation sig- nal and (c) shows the amplitude- modulated carrier signal. In FM, the carrier amplitude is con- stant, while the carrier frequency varies in proportion to the audio signal rate. Figure 2-a shows an FM audio signal, and Fig. 2-b is the frequency-modulated carrier. The AM band is much lower in the RF spectrum than FM; AM spans 535-1605 kHz. while FM spans 88—108 MHz. AM channels are 10 kHz wide and FM channels are 200 kHz wide, so you would be able to squeeze only about 5.5 FM channels onto the entire AM band. There are 107 AM channels presently available, and 100 on FM, FM signals normally don't propagate beyond 75 miles, which is considered the line-of- sight limit and is within the Very- High Frequency (VHF) range. The VHF range used by broad- casters is subject to signal scat- tering from obstructions such as building edges or hills and is prone to fading in and out under certain conditions. In contrast, AM signals often travel veiy great distances. The difference be- tween AM and FM signal propa- gation is due to the great difference in their carrier fre- quencies, not their modulation differences. FIG. 1— AM SIGNAL COMPONENTS; {a) is the carrier signal, (ft) is the modulating signal, and (c) is the amplitude modulated signal at a constant frequency. TWo characteristics of FM oper- ation are responsible for its high fidehty response: wide band- width transmission and con- stant carrier amplitude. The wide bandwidth allows a wider range of audio frequencies to be processed, up to 15 kHz for FM, compared to only 5 kHz for AM. The source of most noise in AM transmission and reception is from atmospheric or static noise resulting from lightning, fluores- cent device radiation, and elec- tronic machinery, especially dur- ing hot weather. AM transmis- sion is, therefore, amplitude- sensitive. By maintaining a con- stant carrier amplitude in FM, static noise can virtually be elimi- nated. FM was originally used for stereo because of its high fidelity. m o z o cc I- o liJ _l w 6 Q < a: 72 FIG. 2— HERE IS AN FM SIGNAL; {a} is the audio modulating signal and (b) is the fre- quency modulated carrier signal at a con- stant amplitude. FM poptilailtjr After World War 11, AM stations began adding FM. There weren't many FM stations back then, so FM programming consisted pri- marily of classical music to take advantage of the high fidelity; otherwise they just duplicated AM programming. FM grew slow- ly, because consumer-electronics manufacturers and the public were mesmerized by TV. Some AM stations gave up on FM. relin- quishing their FCC FM station licenses. They regretted it later, when FM became prominent but, by then, most FM frequency al- locations were gone. Several factors contributed to the prominence of FM. Stereo ar- rived in the early 1960's, becom- ing the foundation of further success. The availability of FM stereo receivers, component sys- tems, AM/FM portables, and AM/ FM car stereos followed. The FCC eventually ruled that most com- bined AM/FM stations had to pro- gram AM and FM broadcasts separately, forcing broadcasters to create competitive FM pro- gramming. There then arose a couple of generations of listeners who used radio mainly for music, not comedy, drama, or news. The growth of FM over AM in the last 16 years has been dra- matic. In 1972, AM had 75% of the radio audience; that was re- versed by 1988. FM is considered the stereo music inedium, which is what most listeners want. However, not all AM is in trouble; large markets capable of develop- ing major audience shares com- mand sale prices of tens of millions of dollars. However, the average AM station is far less glamorous. AM's battie against FM Most mid-size markets have a couple of AM stations at the bot- tom of the ratings. The top two or three in a market get by on com- munity service, creative pro- gramming, good management, and poor competition. Most AM stations that are considered to be on shaky-grounds are those that broadcast daytime-only stations, especially those that have no FM companion station, and aren't part of a broadcasting group un- der one owner. They sink or swim on their own and most drown; about 65% lose money. FIG. 3— AM RADIO TRANSMITTING TOW- ERS aren't the beacons of comedy and drama they were in the good old days. The FCC helped by giving most daytime stations post-sunset broadcast authorizations, but the rules often dictate transmit- ter powers as low as 1-50 watts! Even for a small-town station, that's not enough power to pro- vide the needed coverage, es- pecially if there's competition. AM's crowded frequencies are an- other problem, especially for night listening when signals propagate farther Interference obviously turns listeners away. Many AM channels are a jumble of noise at night, with half a doz- en stations fighting to be heard and none succeeding. In the 1960 s and most of the 1970's, AM rode high, and many broadcasters and investors want- ed part of the market. Hundreds of new stations began during that period, crowding the AM dial. Many towns of 20,000 peo- ple have two or three AM stations competing for large FM au- diences. The economic down- turn of the late 1970's and early 80s hurt many AM stations, es- pecially those in rust and farm belts, which suffered most from the sluggish economy. AM radio generally gets a small slice of local advertising, with the larger chunk going to FM. TV, ca- ble, newspaper shopping, and billboard competition is very heavy. Falling revenues mean less money for promotional or inno- vative program changes, or high- quaiity air personalities that might hold an audience, [n 1988, AM and FM each had about 5,000 commercial stations; AM sta- tions did $1.7-$1.9 billion of business, while FM stations did $4.8-$5 billion. FMs early lack of commercial success helped draw listeners because of fewer com- mercials. And, while FM stations do air more commercials today, they still air about half as many as AM stations — they just charge more. AM solutions AM station managers know the problems, and try to find solu- tions. They know audiences don't see AM as a music medium, A National Association of Broad- casters survey on public at- titudes toward AM found that 75% of respondents want good programming with good tech- nical sound. The survey showed both a strong preference for news-talk-information on AM, and an older audience. Some sta- tions try drastic cures. "Nar- rowcasting" or "niche program- ming" describes programming aimed at very specific audiences: • In New York, WFAN (once WNBC, flagship station of the NBC network) runs an all-sports format; play-by-play, sports talk, and news. • In Los Angeles, with 100 com- peting stations, KMNY devotes it- self to money, and how to have more of it, syndicating some pro- grams to other stations. • All-kiddie radio by KPAL, Little Rock, Arkansas, includes chil- dren's music, stories, and school news reported by children. • In Florida. WWNN broadcasts self-help and positive-thinking radio programs, • Several stations now use sin- gle-theme approaches to music. There are all-Elvis stations, and at least one playing only Beatles music. Whether these formats will last is yet to be seen. For example, all- weather and traffic formats have been tried and abandoned in Los Angeles and Minneapolis. AM stations can also inexpensively subscribe to satellite program services. Services with a "big city" feel have proven successful for smaller stations, especially when such services can mean BETTER RECEIVERS FOR BETTER SOUND One of the main reasons why AM has taken a back seat to FM is because of AM's inherently poor fidelity. The National Association of Broadcasters (NAB) is try- ing to do something atxiut that. Specifical- ly, the NAB is trying to convince electronic manufacturers to incorporate three design improvements into their A(^ receivers. Those improvements, which are in accor- dance with the National Radio Systems Committee (NRSC) suggested guidelines are: the ability to receive frequencies with- in the expanded band. AM stereo com- patibility and, de-emphasis circuitry. Manufacturers will be able to make units that receive transmitted signals in the expanded bandwidth fairly easily and inexpensiveiy. However, they are much more reluctant to jump into mass produc- tion of AM stereo receivers — adsipting cur- rent product designs to incorporate stereo reception can be an expensive proposi- tion. Another stumbling bloct< that manufac- turers face is that there are two mutually incompatible systems on the market. Motorola's C-Quam and Kahn Communi- cations are two AM stereo systems that are currently in use by broadcasters today C-Quam is used by approximately 500 broadcasters, while only about 100 broad- casters use the Kahn System. The only commercially available AM stereo re- ceivers on the market are compatible with Motorola's C-Quam transmitter design. Sony, Sanyo and Sansui previously made 10 stereo detectors that were compatible with both the C-Quam and Kahn transmis- sion systems, and about 20 such receiver models were once produced by those companies. However, those chips and re- ceivers are no longer in production be- cause of various legal battles between Kahn and Motorola. We may again see some Kahn-compatible receivers after the legal dispute is over There ate still many varied opinions in the broadcasting field about which system is better Broadcast engineers profess the advantages of each system, and may choose one system over another because of their specific transmission needs, or personal preferences. When AM stereo was first introduced years ago, FCCls "let the marketplace decide" attitude sealed the fate of AM stereo by causing a re- lentless battle tjetween various competing systems. Now, more than eight years after the introduction of AM stereo, the two sur- vivors, Kahn and Motorola, are stilt bat- tling it out. The FCC's lack of direction during the early stages has hindered the acceptance of AM stereo, and has hurt not only electronic manufacturers, but con- sumers, too. savings through staff cutbacks, or when staff can be freed to de- velop more local and major news programming. It's easy to insert local news, sports, weather, and other features. Frequency boosting, or pre-emphasis is a design modification that the NRSC is recommending to reduce noise transmis- sion for higher fideiffy. Within the time in- terval that an AM signal carrier is transmitted and received, the can-ier sig- nal may tie affected by noise. The greatest impact that noise has on the carrier is changing the amplitude. FM is much less subject to that type of noise distortion be- cause it is transmitted at a constant ampli- tude. The sound volume of an AM detector is proportional to deviation of the carrier amplitude. If the audio signals cause a much larger amplitude change than the unwanted noise amplitude devia- tions, during transmission and reception, then the noise will not be very noticeable. That relationship is called the signat-to- notse ratio— the higher the value, the bet- ter the sound quality. PRE-EMPHASIS CHARACTERISTIC suggested by the NRSC for AM trans- mission. In a pre-emph3sis circuit, a portion of the transmitted signal is bioosted, or p re- emphasized, causing a larger carrier am- plitude deviation. The receiver conversely de-emphasizes, or attenuates that signal. The overall effect is to increase the sign al- to noise-ratio. The accompanying figure shows the 75 pjs pne-emphasis charac- teristic suggested for use. The NAB is woriting closely with the electronic industry to develop a certifica- tion for improved AM receiver designs which follow NRSC guidelines. One idea is to authorize the use of a quality mark that will identify receivers that comply with NRSC standards. Broadcasters are also receptive to the idea of promoting the new design standards in AM receivers. Clearly, AM stereo compatibility and the efforts to improve AM sound quality are compli- cated issues which are still being worked out Perhaps with the cooperation of the electronic industry, broadcasters, and the FCC, AM will continue as a viable commu- nications medium. m Not long ago, AM operators ;^ thought the answer was AM ster- m eo, but it's been a disappointing m panacea. Most broadcast experts 3 feel that the FCC ruined things s by refusing to pick a specific AM o 73 FIG. 4— TALK SHOWS, OFTEN WfTH LIVE GUESTS, are a programming staple of stations of all sizes. FIG. 5— WELL-RUN SMALL-TOWN STATIONS witti a solid history are likely to continue a successful tradition. g z o tr I- o LU _l LU Q < stereo approach from the half- dozen stations competing for FCC approval. Instead, the FCC let the market decide, and so far it hasn't. In the last seven years, AM stereo has barely affected the minds of broadcasters or the public, TWo AM stereo systems are still competing: Motorola's C-Quam, and the system developed by Kahn Communications, Broad- casters haven't reached a con- sensus on which should be standard. Only 10% of AM sta- tions now have stereo. The au- dience percentage that use AM stereo gear is still low, and there's no real impetus to switch, which can cost up to $100.000— half a year's income or more for some small stations, AM's expanded band An important change affecting AM broadcasters as well as radio receiver manufacturers is that of AM frequency band expansion, or 'AM improvement." In 1988. the World Administrative Radio Conference agreed to expand the AM radio upper bound from 1600 kHz to 1700 kHz, effective July 1, 1990. Ten additional channel slots will be available as a result of the expansion. With 20 to 30 stations per channel, a total of approximately 200 to 300 new AM stations in the U.S. could conceivably occupy the expanded band. The primary objective of the FCC in authorizing transmission in the upper range is to unclutter the existing band and reduce the overall levels of broadcast inter- ference. Stations who are consid- ered as causing the most inter- ference will be given highest priority by the FCC for transmis- sion in the upper band. Some night-time broadcasters are con- sidered to be the "worst offend- ers," and the FCC is hoping that most of those stations will volun- tarily migrate into the upper band. The advantage of changing into the upper band is that the adjacent stations will experience less interference, and the listener will receive a much clearer broad- cast. After a transition period, the FCC will make new AM stations available for new licensees, so that broadcasters can make full use of the entire expanded band. Stations who are licensed to broadcast within the new upper range will be able to transmit full- time, with power restrictions of minimum 1 kilowatts after sun- set and 10 kilowatts during daylight hours. Many problems, however, still need to be solved. Existing ser- vices, such as the TVaveler's Infor- mation Stations [TISj will need to move or — because the TIS are considered by the FCC to be sec- ondary broadcasters — may have to relinquish their transmitting rights. So, can we see the future of AM? Clearly, it'll hardly vanish from your dial. Most stations will likely solve problems by new pro- gramming, promotion, manage- ment, and technology. Some may not have their prior success, hav- ing to live with less. But those with bleak futures may die out due to survival of the fittest. That sort of periodic adjustment be- falls most industries, when change creates a new operating climate, killing off and weeding out the weak, leaving what's left leaner and meaner. Meanwhile, those who live and work in the world of AM radio today can only echo Molly's long ago words: "Tkint funny McGee!" R-E 74 IZMnMnXZHHIIHi Perpetual motion, independent research, the magnetocaloric effect, and audio voltmeters. □DN LANCASTER It's not at all obvious to me why we need all of the foot dragging, in- fighting, and squabbling going on today over HDTV high-quaiity video- display standards. It seems that sev- eral government agencies are now battling each other to win the coveted role of chief obstructionist. To me. it is entirely obvious that HDTV wilt use square pixels, will not have intedace, will use fully program- mable, rather than hard-wired (single standard) receivers and displays, wili be totally digital, will use a real-time JPEG compression, and wilt follow Japanese set standards. It is also totally obvious to me that terrestrial broadcasting will sen/e a negligible to totally vanishing role in HDTV, while the computing, satellite, VCR, and cable uses will over- whelmingly dominate. And any inter- mediate or interim "transition" steps will prove to be a monumental waste of time and money, done by the wrong people for the wrong reasons. So, let's just ban the networks and the feds from any HDTV input what- soever and then get on with it. They are the enemy, not Japan. Our topics this month seem to range from the ridiculous to the sublime... Perpetual motion It may be the New Age nineties, or just a sunspot cycle peak, but a sur- prisingly large number of all you hard- ware hackers are busy at work building your own perpetual motion machines. I simply cannot believe the number of helpline calls and visitor drop-ins I am getting on this. Since perpetual motion is definitely real as far as its history and its ongo- ing activities are concerned, maybe we should take a brief look hens. I guess I was in the seventh grade when I built my first perpetual motion machine. Figure 1 shows the details. 1 took a gyroscope and hung several magnets on it so that like poles faced each other. The magnets were at an angle so that the repulsion would have a tangential component. As the poles repelled each other, the gyro- scope would accelerate. Or so I thought at the time. Very strangely the gyroscope locked up instead of spinning. Seems it latched itself into a minimum reluctance field position and just sat there. These days, I guess 1 don't really understand why perpetual motion is desirable. Since unlimited free ener- gy would hasten the entropic heat death of the planet, perpetual motion is both environmentally unconsciona- ble and socially reprehensible. The first thing we should do to a suc- cessful perpetual motion machine designer is to just stake him to an anthill, and then leave him out there until the next meeting of the steering committee. Nonetheless, perpetual motion is a fascinating topic. Some very good books on this subject are available from Lindsay Publications, while a few of the more opportune ongoing perpetual-motion scams are available to you through HSA Industries or the Teste Book Company. After working with a bunch of them, the perpetual-motion buildees these days all appear to share several common traits. None of them have ever attended an introductory college physics course, or else they seem to have slept through it. While all of them claim they "just can't find anything at all" on their idea, they studiously go out of their way to avoid doing any real or honest library research. As we've found out NEED HELP? Phone or write your Hardware Hacker questions directly to; Don Lancaster Synergetics Box 809 Thatcher, AZ 85552 (602) 428-4073 several times in the past, any hard- ware hacker anywhere can instantly get the very latest scoop on anything by way of the Dialog Information Ser- vice. More on this shortly A disproportionate number of the perpetual-motion buildees seem to belong to one particular religion that happens to be very big on faith and on self-reliance. There's often a very heavy dose of paranoia, usually aimed at the patent office, a local university, those oil companies, Detroit (who could not possibly suppress anything except quality or profits), an ex-boss, or else "them" in general. Almost always, the buildees think linearly instead of cyclically. Thus, while a power stroke of the repelling magnets or their freezing milk bottle makes a lot of sense to them, they usually ignore the inevitable repetitive and cyclic energy supplying steps as needed to get to that stage. There's also the Cosmic cupcake syndrome, the Few chips shy of a full jboard affliction , and the Boy a whole flock of them flew over that time con- cept. But we need not get into any of these here. Finally, there is the magic bullet. Their idea almost but not quite works. So, all we need to fix it is better gears, stronger magnets, a larger milk bottle, or a different rear axle ratio. Or more bucks for research. Several of us folks around here at Radio-Electronics editorial have now somehow gotten some silly ideas into our collective heads. For some unbeknownst reason, many of us presently feel that: CA) Neither matter nor energy can be created or destroyed, except by an atomic process. CB) Available energy always seems to convert itself from higher quality forms into lower and less useful ones. Not once have the dishes ever washed themselves. Nor have those pool balls ever re-racked themselves. (C) Nearly all physical and elec- FIG. 1— MY VERY FIRST PERPETUAL MO- TtON MACHINE. As the like poles of the magnets repel each other, they accelerate ttie rotor on a gyroscope. Sadly, it latched, rather than speeding up. But maybe if I used stronger magnets... tronic processes end up producing unrecoverable low-grade heat ener- gy, usually through friction or elec- trical resistance. (D3 Despite a House-Senate com- promise committee, Congress is not expected to repeal the three laws of thermodynamics this session. Para- 1 ^ NEW FROM ~1 DON LANCASTER HANDS-ON BOOKS Hardware Hacker Reprints 11 24.50 Ask The Guru Reprints 1 or II 24.50 CMOS Cookbook 18.S0 TTL Cookbook 16.50 Active Filter Cookbook 15,50 Micro Cookbook vol 1 or II 16.50 Enhancing your Apple 1 or II 17.50 Apple Writer Cookbook 19.50 Apple Assembly Cookbook 21,50 Incredible Secret Money Machine 10.50 LaserWriter Reference-[Apple) 19.50 PostScript Cookbook (Adobe) 16,50 PostScript Ret. Man. (Adobe) 22.50 PostScript Prog. Design (Adobe) 22.50 Type 1 Font Format (Adobe) 15.50 Reat World Postscript (Roth) 22.50 UNLOCKED SOFTWARE LaserWriter Secrets (lie/Mac/PC) 29.50 PostScript Show & Tell 39.50 Intro to PostScript VHS Video 39.50 PostScript Beginner Stuff 39.50 PostScript Perspective Draw 39.50 PostScript Technical Illustrations 39.50 PostScript BBS stuff 19.50 Absolute Reset lie & lie 19.50 App le Writer' Lase rwrl te r UtI 1 !tl es 49.50 Enhance 1 or II Companion Disk 19.50 Apple Writer CB or Assy CB Disk 24.50 ^FREE VOICE HELPLINE VISA/McJ SYNERGETICS Box 809-RE Thatcher, AZ 85552 (602) 428-4073 A CIRCLE 83 ON FREE INFORMATION CARD phrased, these three laws are (1) You can't win; (2J You can't break even; and (3) Yes, the dice are crooked, but its the only game in town, I guess one of the reasons some of us around here feel this way is that not once in the entire history of hard- vrare hacking has even one reproduci- ble counter example to these silly ideas of ours ever been successfully and unarguably demonstrated. Naturally, you are free to agree or disagree with us as you wish. But if you disagree, we do make only one simple request: Provide us with an experiment that can be independent- ly duplicated by disinterested out- siders which causes your effect to show up at least reasonably well. Then we will all believe. Doing serious researcli So, what is the best way to re- search any topic? I don't know how many calls and letters I have gotten from people who live in such a "re- mote" area and will claim that "abso- lutely nothing" is available locally. Believe it or not, one of these letters was from Cambridge, MA and yet an- other was from F^lo Alto, CA. Well, I've been sitting right here watching Gila Monsters on this sand dune smack dab in the middle of the Upper Sonoran desert for nearly two decades now. While almost every- thing I do is local Cand much of it done underground or in mountaintop wil- derness areas), I've had no problems whatsoever handling top-quality re- search on all kinds of very rewarding and well-paying topics. So don't give me any "remote" bull. Admittedly, my tiny and isolated town of 2400 does have its own sym- phony orchestra, but that's another story. Figure 2 lists a few of my key se- crets to doing independent hacker research. The overwhelming reason you cannot find something is be- cause you are not looking. You are instead going through some inept motions and keeping yourself busy, rather than by taking obvious steps and handling all of them in a logical manner Research is not an activity that you turn on or off. Instead, you put your- self in a continuous research mode in which you gather and collect everything, needed or not, or ex- pected or not. Never mind the topic. The subject does not matter in the least, since chance favors the pre- pared mind. Thus, your own personal resource file is far and away the most important place to look, should any specific need come up. Set a minimum goal of eight cubic yards for your personal resource files. At least for a bare bones start- up. Then let it grow From there. Your foremost outside resource should be all of the trade journals. I subscribe to over 400 of them. As we have seen in the past, any and all fields have all their own private tech- nical magazines which are intended for a select group of insiders. Most of these are free, provided you tell them what they want to hear on their qualification cards. Many do Include bingo cards, annual directories, and tech info. Naturally, you'll circle everything even remotely usable on the bingo cards. If in doubt, circle it. If you do not personally rent the largest box in your local post office, you've missed the point here completely. Electronic trade journal examples include E.E. Times. Electronics, EDN, Electronic Products, Electronic De- RARE EARTH RESOURCES ABS3r Box 8247 Ward Hill Haverhill, MA 01835 (800) 343-1990 CIRCLE 259 ON FREE INFORMATION CARD Atfa Products PO Box 8247 Ward Hill, MA 01835 (800) 343-0660 CIRCLE 2«0 ON FREE INFORMATION CARD Cerac PO Box 1178 Milwaukee, Wl 53201 (414) 289-9800 CIRCLE 261 ON FREE INFORMATION CARD ESPI 5310 Derry Agoura, CA 91301 (800) 638-2581 CIRCLE 262 ON FREE INFORMATION CARD Fisher Scientific 711 Forbes Avenue Pittsburgh, PA 15219 (412) 562-8300 CIRCLE 263 ON FREE INFORMATION CARD Goodfellow 301 Lindenwood Drive Ste 1 Malvern, PA 19355 (800) 821-2870 CIRCLE 264 ON FREE INFORMATION CARD 76 I (2) (3} r (6)- k' (9)- K (10) If you can't find it. you ain't lookin. Research is a continuous activity done on a total tifestyte basis. You cannot turn it on and off at will. Anticipate what you are going to research in the future and get started on it long ahead of any actual or possible need. Your own personal resource file should be your first and foremost starting piace. Your begining file should fill at least eight cubic yards, and should expand from there. The (fee trade journais are far and away your most important external resource. A complete (isting appears in Uhlricht's Periodicals Dictionary. Use those bingo cards! The Dialog Information Service at your local library can instantly find anything for you from anywhere at anytime. Other important library resources are the Science Citations Index, the Thomas Registn' of Manufacturers, Interlidrary loan, the UMI reprint service, and the Encyclopedia of Associations. Form an extensive network of contacts outside of your circle of family, friends, or work associates. Clubs, helplines, and BBS systems are ideal for this sort of thing. Let your subconscious be your guide, starting from fundamental principles and guidelines. Go with the vibes Quest tinajas. FIG. 2— SEVERAL OF MY INSIDER secrets on independent research sign, and dozens more. We'll look at these names and numbers in some future sidebar. For now, you go to the library and view the Hacker's Holy Grail, tfiat is otherwise known as the Utilricht's Periodicals Dictionary. This one hard- ware hacking resource is far and away more important than all of the rest put together Use and enjoy. The second most important out- side Hardware Hacking research re- source is the Dialog Information Service. It's also at your local library. For a small fee. Dialog will instantly research anything, anywhere, any- time. As an example, we'll shortly be looking at magnetic refrigeration. To get From knowing virtually nothing on the topic to having eighteen of the most recent worldwide key abstracts in hand took me a total of seven min- utes and cost me a total of $27.57. There's lots of other goodies in the library, should you snoop around in enough nooks and crannies. In gener- al, the least valuable things in any library are its takeout books. There's that free Interlibrary Loan Sen/ice which lets you get anything from any- where, and the faster UMI service which can get you any reprint of any- thing provided you know the exact title, journal, and pages. For much less than Dialog, as long as you don't mind waiting a few days. There's also a Thonias Registry of Manufacturers that lists who makes everything, but I've found this to be of limited utility. Also, check into the Encyclopedia of Associations, and, if you can't locate Uhlricht's, then the International Standard Periodicals Dictionary is almost as good. Another library favorite of mine is the virtually unknown Science Cita- tions Index. Unlike all the others, this one lets you move forward through time, rather than back into older and older material. It works by listing who put whom into their bibliographies. For instance, any competent new technical paper on active filters must reference Sallen and Key. Anything new on cold fusion absolutely must list Pons and Heischman. Anything new on unfocused solar collectors simply must cite Winston, and so on. If they don't, then they aren't worth reading anyhow Simply shove any of these names through the index, and you'll generate all of the newer papers In the field. After a while, new author names will start cropping up and repeating. You then use the avalanche effect to find the latest and the best, just by start- ing with one or two ancient authors. And do not ignore the library's kid- die, young adult, or popular press books. Excellent, understandable, and readable backgrounds are easily picked up in the Doubleday Science Series, or the Life Science Library. Beyond the library, you'll want to collect the specialty direct-mail books catalogs. We've covered this resource in depth in a previous col- umn and contest. More details ap- pear in my Hardware Hacker II reprints. Let's see. What else is there? You'll definitely want to set up some sort of extensive personal network that involves people strictly outside of any friends, family, or work associ- ates. Obviously, my help line works like a champ here. Electronic bulletin board systems are another great route to networking. So are clubs. Your own personal experiments can very much clarify any topic, as can teaching a class on it. The pur- pose of research is to get the effect you are after to show up reasonably well in as simple and as cheap a way as possible. But stay in school forever While there's lots of possibilities here, the best I've found are local community college courses, and that self-study material from Heath. Finally, simply let things gel. Take Bowseretta up the mountain. Quest a tinaja. Map that terminal crawlway. Any field has an order and a flow to it. Often in directions that "they" don't care to admit. Start with a few funda- mentals, think about it for a while, and a pretty fair picture of the rest may fall in place without much in the way of conscious inten/ention. Remember that sincerity is every- thing. Once you've got that faked, all else follows. This month's contest Tel lya what. I am about to reveal here for the first time a stunning new technological breakthrough, one that is eminently hackable, besides being a sure fire winner for a research topic, school paper or science-fair entry. Only instead of me doing all the work, let's try doing it together See how much you can improve your re- search skills along the way. Just show me an easily done and Radio-Electronics-compatlble method to demo the magnetocaloric c effect described below, at room or lower temperatures. Or else add in [ any way Cpatents, papers, articles, I data sheets, etc.) to our ongoing : magnetic refrigeration dialog below. ; There'll be all the usual Incredible < IT CO O z o cr \3 ill 6 Q < FIG. 3 — THE MAGNETOCALORIC EFFECT, very greatly oversimplified. Gadolinium and other rare earth alloys can absorb heat energy in the presence of a magnetic field and release it otherwise. The efficiency can be as much as 40:1 better than mechanical cooling. Magnetic refrigeration is usable over an absolute zero to above room temperature range. Important first uses will be in cryogenics, superconductivity, liquefied gases, and hydrogen fuels, Secref Mon&/ Machine book prizes, along with an all-expense-paid (FOB Thatcher, AZ) tinaja quest going to the very best of all. As usual, send your written entries directly to me here at Synergetics, rather than di- rectly over to Radio-Electronics editorial. Magnetic refrigeration There's apparently a brand new way to cool things that is just turning the corner from laboratory to pre- liminary product development. If what has happened so far is to be believed, it shoulcf completely blow away many traditional cooling schemes, par- ticularly at very low temperatures. This genuine breakthrough is called the magnetocaloric effect, and I have grossly oversimplified it in Fig. 3. The latest key papers appear in the listings of Fig. 4. Basically, if you take critical rane earth elements or their alloys, they will absorb heat when magnetized and release heat otherwise, acting as a heat pump. At least over certain temperature ranges and over spec- ified magnetic field strengths. Gadolinium is one popular material. Heat transfer operations take place in and around the Curie Point. Most magnetic materials lose many of their properties when they exceed their Curie Point temperature. The magnetocaloric effect can bg tuned over a range of absolute zero to above room temperature. Efficien- cies as much as 40:1 better than me- Magnetocaloric Effect in Strong Magnetic Fields A.M. Tishin, Cyrogenics (UK). Febrjary 1990, v30 #2, pp 127-13$. Magnetocaloric Effects In Rare Earth Magnetic Materials A.S, Andreenko. et. al.. Soviet Physics (USA), August 1989, v32 #8, pp 649-664, Magnetocaloric Effect in Thulium C.B. Zimm, el al,. Cyrogenics (UK), Saptember 1989, v29 #9, pp 937-938. Magnetic Refrigeration Superconductivity Industries, Spring 1989, v2 #1 , pp 32-41 . Magnetocaloric Effect and Refrigerant Capacity of Tt>-Dy Alloys S,A. Nitkin, et,al, Physics Status Sotidi (East Germany). May 1989, pp 117-121, Magnetic Refrigerator for Superconducting Magnets at 1,8K V.A. Allov, etal.. tCEC 12 (UK). 1988, pp 635-640, Magneto-thermal Properties of Sliitered Gadolinium E. Gmelln, et al., ICEC 12 (UK). 1988, pp 432-436, Deter mination of Ihe Cooling Capacity of Magnetic Refrigerants S. Nikilin, et. al., Soviet Tecfinical Ptiysics Letters, April 1988. v14 #4, pp 327-328. Magnetic Refrigerator T. Hashimoto, Relrigeratiort (Japan), 1908. v63 #733, pp 1 189-1201. Magnetic Field Changes In the Entropy of Europium Sulphide P. Bredy, et,al, Cyrogentic (UK), Sept 88, v28 #9, pp 605-606. Mag netot hernial Conductivity of Er-AI for Cyrogentc Applications C,B, Zimm, et,a!,, Jourrtat of Applied Physics, 15 April 1985, V57 #6, p4294-4296, Adiabatic Temperature Changes in Ferromagnetic Intermetalllc Compounds C.B. Zimm, etal., Joumat of Applied Physics. 15 April 1985. v57 #8, p3829. Magnetic Relrigeratton T. Hashimoto, et. al.. Solid State Physics (Japan). March 198S. v£0 #3, pi 61-175, Characteristics of Magnetocaloric Refrigerants below 20K T. Hashimoto, et.al., ICEC 9 (Japan). May 1989, pp 26-29, A Composite Material for Magnetic Refrigeration Usmg Internal Heat Transfer. B. Daudfn, et.al. Cyrogenics (Great Britian). September 1982, v22 #9, pp 439-440, Magnetic Refrigeration from 10K to Room Temperature T. Hashimoto, et.al., Cyrogenics (Great Britian), November 1981 , v21 #1 1 , pp 647-653 T-S Diagram tor Gadolinium Near the Curie Temperature S. Benlord. el. a!,. Journal ol Applied Physics, f/arch 1 981 , «52 #3, pp 21 10-21 1 2: The Magnetocaloric Effect in Dysprosium S. Benlord, et,al. Journal o( Applied Physics. March 1979, v50 #3, pp 1868-1870. 1 FIG. 4— A FEW OF THE RECENT PAPERS on magnetic refrigeration and the new magne- tocaloric effect. 0.0 IS nF lOnF I DC OUT ■t^6V0C FIG. 5— AN AUDIO VOLTMETER having a range of to - 80 dBm. Use ttiis one to calibrate microptiones and speakers, or as a receiver "S" meter. Output is 0.5 volts at - 80 dBm and 5 volts at dBm. Sensitivity is 10 microvolts. chanical refrigeration have been bandied about. Yes, the effect can be done using no moving parts. Obvious applications for magnetic refrigeration include cryogenics and superconductivity, the production of liquid gases (especially hydrogen as a fuel), and as Freon replacements for traditional room air conditioners. A few sources of gadolinium and its re- lated rare earths are shown in our continued on page 90 78 all the sensors are blocked. You should notice that the left wheel will slowly change from a coun- ter-clockwise to a clockwise direc- tion and the right wheel will change from a clockwise to a counter-clockwise rotation. If the Lawn Ranger has passed all tests so far, it is ready for outdoor test- ing. If it did not pass one or more of the tests, double check the opera- tion of the CPU board as de- scribed in the June issue. Outdoor guidance testing Now it is time to have some real fun! Make sure your neighbors or friends are out because they wiU love to see the capabilities of your new creation. Cut a six-foot thick square border around a small grassy lest area with a conven- tional lawn mower (don't use the Lawn Ranger yet). Connect the manual controller, squeeze the CO m m m 7S Put Professionol Knowledge ond a COLLEGE DEGREE in your Technical Career through HOME STUDY Add prestige and earning power to your technical career by earning your Associate or Bachelor degree through directed home study, Grantham College of Engineering awards accredited degrees in electronics and computers. An important part of being pre- pared to move up is holding the right college degree, and the abso- lutely necessary part is knowing your field. Grantham can help you both ways — to learn more and to earn your degree in the process. Grantham offers two degree pro- grams—one with major emphasis in electronics, the other with major emphasis in computers. Associate and bachelor degrees are awarded in each program, and both pro- grams are available completely by correspondence. No commuting to class. Study at your own pace, while continuing on your present job. Learn from easy-to-understand lessons, with help from your Grantham instruc- tors when you need it. Write for our free catalog (see address below), or phone us at toll-free U800-955-2527 (for catalog requests only) and ask tor our "degree catalog." w o z g I- u LU _l LU 6 Q < Accredited by the Accrediting Commission of the National Home Study Council GRANTHAM College of Engineering 250 Frontage Road Slidell, LA 70460 POWER BOARD COMPONENT SIDE AT HALF SIZE. POWER BOARD SOLDER SIDE AT HALF SIZE. hand switch and turn the Lawn Ranger on. "Walk" the unit to the cutting area and place it on the edge of the grass border with the tall grass positioned to the left — see Fig. 1 of the June issue. Adjust the height of the grass sensors so their tips lie approxi- mately one inch above the cut grass. The uncut grass should be around two inches higher than the cut grass for your first test. Remove the manual controller and push the run button. The mower will begin to track along the border you previously cut. It should continue tracking this border until you stop it. If it pass- es this test, you are ready to con- nect the cutting blades and really show off. Final test Now you are ready to connect the blades as shown in Fig. 3 (make sure the batteries are dis- connected before attaching blades). Double check the shields that surround the cutting blades; they should be able to withstand a force as high as 60 pounds upon impact to allow for safe operation. After the blades are attached, grab yourself a cold drink and "walk" the Lawn Ranger with the manual controller to the test area. Set up the mower as de- scribed above and connect the cutting-motor wire to Jll-2, Re- move the manual controller and turn the Lawn Ranger on. Push the CUT and run button. Now, watch in amazement as the mower automatically cuts the grass contained within the test area. You will love the way it "turns on a dime" when it reaches the end of a row. When it is finished with the job, it will steer in a tight circle searching for tall grass and then turn off R-E 80 AUDIO UPDATE The Sound of Audio: An AES conference report LARRY KLEIN Last month I wrote about an au- diophile High End Hi-Fi Show. This column is about an al- together different kind of "show" sponsored by the Audio Engineering Society (AES). Properly billed as a conference, rather than a show, "The Sound of Audio" was a wide-ranging exploration of the latest findings on the perception, measurement, re- cording, and reproduction of sound. A variety of papers were presented along with a special session on the reviewing of audio products featuring reviewers from both "slick" and "un- derground" publications. Given my 20 years in charge of product review- ing for Steneo Review, I heard nothing new — although the session gave me a chance to say hello to a lot of old friends. However, the pertinent and intelligent questions from the au- dience led me to make a mental note to discuss the somewhat controver- sial topic of equipment reviews in a future /Aud/o Update column. Now, on with the conference. Pyschoacoustics Because of my ongoing interest in psychoacoustics, 1 found the several sessions devoted to audio percep- tion both interesting and enlighten- ing. As you may know, psycho- acoustics deals with subjective sonic perceptions, as contrasted to objec- tive sonic measurements. A simple example; For a sound to be heard subjectively as twice as loud, its ob- jective increase in sound-pressure level must be approximately 10 dB. The three presenters were all uni- versity researchers, and their talks included some of their own original research in addition to the very latest findings in the field. Rather than at- tempting to synthesize three lengthy, and sometimes complex, papers, I'll extract (and paraphrase when neces- sary) some of the opinions and find- ings that caught my ear • Despite hundreds of years of in- vestigation into human hearing, many mysteries and confusions remain. One author discussing the difficulties of operating in the area of qualitative judgments (Is it twice as loud or V/2 times as loud?) urged that because we are trying to measure the behavior of a very complex biological system that we be skeptical of the derived numbers — -they might not mean what we think they do. I got a strong feeling that there is an enormous amount of research that remains to be done, and that digital manipulation of the testing signals is an important new facilitating tool. • There is more to hearing loss than a simple reduction of sensitivity to WHO IS AES? The AES is an international organi- zation whose membership includes more than 10,000 persons involved on a professional, semiprofessional. and amateur level in all aspects of audio. For further information on The Sound of Audio conference, on how to become a member of the AES, '■ and'or a catalog of avaiiabie publica- ' tions and technical papers, write to: Audio Engineering Society, 60 East 42nd Street, New Yorl<, NY 10165-0075. various frequency areas. Unfor- tunately, at the frequencies where there is a hearing loss there are also additional changes that affect per- ception. Thus, we generally cannot restore normal perception tDy simply restoring normal sensitivity with a hearing aid or by using equalizers or tone controls in a hi-fi system. The study of the perceptual con- sequences of hearing loss is an im- portant and very active research area of psychoacoustics and audiology. • The ear has an incredible absolute sensitivity; At 3 kHz. where the ear is most sensitive, a sound at the thresh- old of hearing produces a displace- ment of the eardrum that is about Vioo of the diameter of a hydrogen mole- cule! The threshold of pain (ranging from 140 dB at 20 Hz to about 1 20 dB at 2 kHz) is generally given as the upper intensity limit of hearing. Unlike the eye, whose iris visibly adjusts it- self to the ambient illumination, the ear maintains its approximately 120- dB dynamic range by dividing dif- ferent intensity levels among sepa- rate groups of nerve fibers. Each of the fiber gnDups can handle a range of only 30-^0 dB. At levels about 40 dB or so. only about 15— 20% of the ear's 30,000 nerve fibers are handling the incoming sounds. • It is almost always incorrect to refer to the loudness of a sound as, say, 90 dB SPL. Sound pressure level is a physical measurement and only indirectly related to loudness, which is a subjective evaluation. A sound measuring 90 dB could be, depend- ing on its frequency spectrum, loud or quite soft. • There's a new interest in sound- localization research. Some recent findings include: Complex, broad- band sounds are localized best, high frequencies must be present for accurate judgment of a sound source's apparent height, and lo- calization is most precise for signals in front and at ear level. It has been generally accepted that our brain localizes sound sources by using the intensity and timing dif- ference between the sounds reach- ing each of our ears. Although research has shown that the specific convolutions of our external ears Cpinnae) cause reflective cancella- tions and reinforcements of signals before they reach our ear canals, only recently has it been understood that this direction-dependent spectral fil- tering plays an important role in our ability to localize sound sources. Another recent experiment on di- cc rectional perception sought to deter- t mine the relative importance of g interaural arrival-time versus sound- a intensity differences in determining j localization. By digitally manipulating „ the signal, the experimenters were = 8 ELECTRONICS PAPERBACKS n BPHT— PRACTICAL ELECTROmC BUILDING BLOCKS. BK-1 S5.75. Circuits for a number of useful bgetding blocks are presented. Combine these circuits to build Ihe devices you need. D BP192— MORE AD- | VANCED POWER SUP- PLY PROJECTS $5.95. 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Provides Ihe casual lis- tened, amateur radio OXer and Itie professionat radio monitor with ah essential reference work designed lo guide him or her around ihah ener more complex ra- dio bands. MAIL TO: Elei;tTanic TechnoJogy Today, Inc. RO. Sox 240 Massapequa Park, NY 11762-0240 SHIPPING CHARGES IN USA AND CANADA SO.OItoSS.OC S1.25 $5 01 io 10.00 S2.00 $10.01 to $20.00 $3.00 $20 01 10 S30.00 54.00 SORRY, No orders accepted outside of USA and Canada S30.01 lo $40.00 S5.00 S40.01 to S50.00 16.00 $50.01 and above $7.50 Total price of merchandise Shipping (see chart) , . Subiotal Sales Tax (NYS only) , . . , Total Enciosad Name. Address . City ^ I . State . -Zip. able to feed the test subjects conflict- ing intensity and timing information. The expectation was that the sub- jects would "split the difference," but instead it turns out that the difference in interaural arrival time was the domi- nant localizing factor — as long as fre- quencies below 2 kHz were part of the signal. The authors concluded that this newly discovered time-difference dominance means that "modification of the intensity ratio between the right and left channels of a stereo recording cannot be expected to have any influence on the apparent position of the resultant sound im- age." I think I missed the author's point, because as far as I can tell my preamplifier's balance control (which operates by adjusting the relative gain levels of the right and left chan- nels) works as well as ever The final paper on the localization of sound sources related a series of complex experiments that set up "unnatural" acoustic conditions (such as having one reflecting wall in an otherwise anechoic environment) and used highly controlled, and equally unnatural, special acoustic test signals. It turns out that the sub- jects unconsciously evaluated the plausibility of the test signals against their real-word experience and ig- nored or re-weighted sounds that made no sense. An example of a non- sensical signal would be one in which the arrival-time differences between the ears exceed the maximum possi- ble (about 765 microseconds) for the human head, or one in which the de- layed reflected sound was louder than the direct sound. The paper didn't cover another re- lated phenomena — the ear/brain's ability to localize sounds where they "should" be rather than at their actu- al source. For example, when listen- ing to a performer on stage from anywhere in the audience, most peo- ple hear the sound coming from the performer rather than from the au- ditorium's speakers — assuming the sound system isn't grossly mis- balanced. And, on a cozier level. most people have no problem when viewing the TV while wearing head- phones in placing the dialogue at the actors' mouths rather than at the real source — directly over their own ears. Next month we will look at some of the other papers dealing mostly with the hardv\7are of audio. R-E TELEPHONE LINE continued from page 46 PC type bracket, and cut open- ings for Jl and J2. Installation With the modified bracket in- stalled on the card, it is very sim- ple to install in an IBM PC or clone. All you have to do is locate an unused slot in your comput- er's expansion bus. Make sure the computer is off during the in- stallation. Remove the blank mounting bracket from the back of the computer (if one exists), and insert the new card into the slot. Install the mounting screw, and then plug in the phone line and the AC adapter and battery backup if used, and you're ready to roll. Software The software is menu driven and, in most cases, a single key stroke is all It takes to change mode or to perform an operation. Screen colors are used for high- lights, and for separation of fields. The only thing you have to remember is to type TLC and hit return (from the DOS prompt). All programming, functions, and mode selections thereafter are done using menus. (See sources box for custom software.) The software consists of two programs: the operating pro- gram and the resident program (which are available on the RE- BBS— 516-293-2283). The oper- ating program runs on the host computer and provides the inter- face with the controller's hard- ware. The resident program is what the operating program loads into the on-board SRAM. The resident program is the actu- al program that determines what the controller will perform. But it is the operating program that is used to select, configure, and load the resident program. User registration cards Although the software is not copy protected, we strongly rec- ommend users to register their ■ copies; doing so will automat- ically put you on AC&C's mailing list. AC&C will inform users of new applications software, func- tions, and updates. R-E 82 l=M'''^t-^H=l-M=< This month begins our discussion on control circuitry. n^jUMiMimij Designing and building elec- tronic controllers used to be a really difficult job if you wanted tfie circuit to have enough intelligence to do even fairly complex jobs. The reason for that was that there weren't any single-component solutions to electronic intelligence. But when IC's were developed, and affordable microprocessors ap- peared on the market, things began to change dramatically. The major change in controllers was the home computer in general and the marketing of cheap mother- boards. That's because all the intel- ligence you'd ever need could be handled by an eighty dollar clone and a bit of software... almost. The reason for the "almost" is that, even though a cheap PC clone has all the brains and memory needed to control your home's security system or the environmental control system of the space shuttle, there's no con- venient way to let the computer talk to the outside world. All home computers have the ca- pability of talking to an external de- vice since they have to deal with video, keyboards, printers, and so on. How they do that depends on the particular computer since different microprocessors handle I/O in their own unique and often strangely won- derful way Fortunately for all of us, just about all of the popular clone computers are built around the 80XXX family — ^from the original 8080, the Z-80, to the 8088 and its more powerful kin, the 80286, 80386, and whatever other surprises Intel comes up with in the future. All those microprocessors deal with I/O in the same way; through the use of only two instructions IN and OUT The chip understands that it can be told to address two completely different kinds of locations: memory and ports. If you think of the comput- er as being an active controller, the former kinds of locations are for thinking and the latter are for doing. It's really that basic. If you look at the pinouts of any of the 80XXX family you'll see that there's one pin labelled lO/MEM. On the 8088, for example, you can see that in Fig. 1 on pin 28. That's the control pin that lets external circuitry know whether the microprocessor is doing a memory operation or an I/O (port) operation. In ordinary use, most people are liP y /o u /3 /¥ /s- /6 ni /s A/o A-, Aa AOj AD^ ADs- AD4 AD^ AOj2 ADi APo A/ Ml ///TA CJ,M. GNO r^ •^cc W [ ^/^ "W AS/i/£3 30 M,t/-^¥ 57 /I/S/^S 3& Al/f/Ss 5S\ ^ sa 3^ aw/ma 33 80 88 32. \ 3/ ///J>A 30 /T/Q ^9\ /a/MEAA Z3 £>T/R 27 £>£:N 3.& Al^E. 2€ ///TA Z¥ r£.sr ZZ /Q/=AOy Z2.\ 1 ^£^eT 3.f FIG. 1— LOOKING AT THE PINOUTS of the 8088, pin 28 (JO/MEM) is the control pin that lets external circuitry know whether the microprocessor is doing a memory operation or an I/O (port) operation. happily unaware of what kind of in- struction is being executed even though both kinds happen all the time. Remember that printers, mod- ems, mice, joysticks, and so on are all treated by the 8088 as I/O devices. Interestingly enough, even though chips like the 8088 make it easy to deal with I/O, designing the circuitry to be controlled is always a pain in the neck, since even the lowly 8088 can handle more than 64,000 different port addresses. That means that any- thing designed to be driven by the 8088 has to be able to recognize when a particular address shows up on the bus — and that means design- ing the circuitry necessary to keep an eye on as many as sixteen different address lines to decode the few that you're interested in. Some months ago I published the details of the Port-A-Matic CRadio- Electronics, January and February 1990) which would decode some of the address lines and indicate when the 8088 was talking to particular ports. If you glance thnDugh the text of the article, you'll get an idea of just how tedious address decoding can really be. When you're going to use a store- bought computer as the basis for a controller it makes a lot of sense to see if you can possibly get away with not having to do address decoding. You need circuitry to create a work- ing port. This usually takes the form of address decoders, latches, and a wad of logical glue to hold the whole thing together. If the port you're de- signing has any special needs, that means even more silicon. An exam- ple of that would be something like a port aimed specihcally at serial stuff where you had to have UART's, tine drivers, and so on. w. There are several standard port lo- t cations in the magical kingdom of g cloneland, and I've listed the most a popularones in Table 1. Notice, as we i just discussed, that most of the ports u actually use several sequential port c 8: R-E Engineering Admart B Hates: Ads are 2'/*" x 2%". One insertion $950. Six insertions S925. eacli.TWelve ■ rtions S895.e3ctT. Closing date same as regular rate card. Send order with ittance to Engineering Admart, Radio Electronics Magazine, 500-B Bi-County Farmingdale. NY 11735. Direct telephone inquiries to Arline Fishman, area code-516-293'3000. Only 100% Engiaeering ads are accepted far this Admart. . INCREASE YOUR EARNING POWER! LEARN TO DESIGN WITH SINGLE CHIP MICROCOMPUTERS i SINGLE CHIP MICROCOMPUTER PRIMER FOR MOTOROLA GBDS * Pro'Hs^nal Ou&htp' MS-DOS Sd^v* -Eotor - *.iMrrib!*T ' S^^qIei i^t\p hu^tozwrtpnAtf Pnmtf Lesscun. boat. Price , . . , S195 I HCPM-1 Progt^irvivitr lor MOlonto HCU7t)5P3,P5,i;].U5,R3,HS 1 PUrtt lijl w/drnter prO^HW ...,.„.. 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'jwW*: BP182 — MIDI irterfacing enables any so equipped instruments, regardless of the manufacturer, to be easily connected to- gether and used as a system with easy com- puter control of these music systems. Combine a computer and some MIDI instru- ments and you can have what is virtually a programmable orchestra. To get your copy send S6.95 plus $1.25 for shipping in the U.S. to Electronic Technology Today Inc., P.O. Box 240, Massapequa Parle, NY 11762-0240. .CIRCLE tS5 ON FREE INFORMATION CARD CIRCLE 179 ON FREE INFORMATION CARD J o O QC \- O LU < addresses to handle data, control, and status. That is important to keep in mind because one of the major drawbacks of designing around someone else's hardware is that things aren't set up the way you'd like them to be. There are actually two problems: The first is that not all the data bits may be used, and the second is that some of the bits may be designed to be either read only or write only. The best way to see that is to look at the port that's available on most clone systems- — LPT1, the main printer port. Just about every clone board I've seen (including the more well-known name brands) that provide an LPT1 port uses the same I/O address space. The three I/O ports that go into making the printer port are 03BCh (the data port), 03BDh (the status port), and 03BE (the control port). The computer uses the data bits at those locations as sum- marized in Table 2, The control port at 03BEh is de- signed to be both written to and read from, although bits 5, 6, and 7 are unused. Bit 4 is used by the port but is designed as a hardware flag to en- able the interrupt that the computer uses to find out whether or not the printer can accept data. The bottom line is that bit 4 is only used internally and doesn't show up on the porl con- nector. Keep that in mind because TTiBLEi' COMMOM POUT ASSf6MMMItTS ^OA.T SFSh COMMENT ^/AT^ PORT - OSSCA ~ M'jf/rS O/VLy &rrs O -7 - £>/^7l4 STA TUS fiOMT - OSMDM -AEAi> O^/LV S/TS o-z - uNusca 3/T -/ - S£^^JCT S.TATLIS 3/T £" - P^f'SR OUT 3/T £ - ACM 3/r 7 - SUSY 3/T — ST^