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HOW TO SERVICE a1IOi CD PLAYERS lectron 1 NOVEMBER 1939 s TECHNOLOGY - VIDEO - STEREO - COMP! TF ue § BUILD R -Es V1DF^ SCENE SWP.* Add professional effects 4.4 eye. home video movies

BUILD DIGI-COMPAS Interface an electronk compass to your compute' CIRCUIT COOKBOOK How you can put CMOS bilateral switches to work ALL ABOUT RELAYS How to choose the right relay for your application

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COM 1 BOMA TRUE RMS MULTIMETER Great Choice. More professionals in more industries The popular 70 Series-simply put, the Your choice. For the name of your make Fluke their first choice in most requested DMM in the world, with nearest Fluke distributor, call toll -free multimeters. nearly 2 million units in service since 1 -800 -44 -FLUKE, ext. 33. And make a 1984. And the Fluke 21 and 23-70 Series great choice. Fluke DMMs. Reliable. Accurate. Powerful. simplicity in high -visibility yellow. Tough. Versatile. Easy to use and simple to John Fluke Mfg. Co., Inc. P.O. Box C9090 MIS 250C Everett, operate. Backed by the longest, most The Fluke 25 and 27-the most rugged WA 98206. U.S.: (206)3565400. Canada: (416) 8907600. Other Countries: (206) 356-5500. ®1989 John Fluke Mtg. Co., in meters ever built, totally sealed against comprehensive warranty the business. Inc. All rights reserved. Ad No. 0491-F70 Made in the U.S.A In short, Fluke makes water, dust and other contaminants. reputation on. meters you can bet your And the precise 8060 Series-with the More choice. No matter what the job, versatility of a test lab, the accuracy of a there's a Fluke to handle it. bench instrument, and the convenience FROM THE WORLD LEADER of a handheld. There's the new 80 Series-the most IN DIGITAL MULTIMETERS powerful, most complete test and Smart choice. Compare Fluke DMMs measurement system available in a with any other handheld. No one else gives handheld package. you as much meter for your money. And no other meter costs less to own. FLUKE CIRCLE 121 ON FREE INFORMATION CARD www.americanradiohistory.com November 1989 1iàtronics.. Vol. 60 No. 11

COMPUTERDIGEST BUILD THIS , , 33 VIDEO SCENE SWITCHER Make your home videos look like professional productions. William Sheets and Rudolf F. Graf

39 R -C- DECADE BOX Find the right substitute resistors and capacitors. Michael A. Lashansky 43 DIGI-COMPASS Modern technology meets a tried-and-true navigational device. Thomas E. Black

PAGE 83 52 HOW TO REPAIR CD PLAYERS The basics of CD operation, and handy troubleshooting tips. Brian Phelps

Lfill) I lit_` 83 THOROUGHLY MODERN MODEMS How to pick the right modem for your needs. TJ Byers

f11-111W 54 BILATERAL SWITCHES switches. Learn how and when to use these electronic -, Ray Marston 59 ALL ABOUT RELAYS PAGE 39 How you can put them to work for your applications. Harry L. Trietley

DEP ,o AND MORE 6 VIDEO NEWS 74 AUDIO UPDATE 106 Advertising and Sales What's new in this fast - The sound of CD: Part changing field. Larry Klein Offices David Lachenbruch 106 Advertising Index 24 EQUIPMENT REPORTS 12 Ask R -E ACE Communications ÁR2515 78 DRAWING BOARD 107 Free Information Card scanning receiver and PC Photography AVCOM PSA-65A portable Robert Grossblatt 16 Letters spectrum analyzer. 90 Market Center 64 HARDWARE HACKER 83 EDITOR'S WORKBENCH 26 New Products More on cold fusion. Software and book reviews. Don Lancaster Jeff Holtzman 4 What's New

www.americanradiohistory.com ON THE COVER Radio

While video camcorders have Electronics surged in popularity over the last

How TO SERVICE couple of years, home video movies CD PLAYERS have become a hard sell. Camcor- ders make it so easy to record Hugo Gernsback 11884-1967) founder M. Harvey Gernsback, events that most people end up editor -in -chief, emeritus BUILD R -E's VIDEO SCENE SWITCHER shooting much more tape than any- Larry Steckler, EHF. CET. one is willing to watch. Only careful editor -in -chief and publisher BUILD DIGICOMPASS editing can bring those boring vid- EDITORIAL DEPARTMENT CIRCUIT 00006000 eos to life. Brian C. Fenton, editor Our Video Scene Marc Spiwak, associate editor Af.. ABOUº RELAYS Switcher helps the editing process providing a wide Daniel Goodman, technical editor variety of wipes and fades that Teri Scaduto, assistant editor Jeffrey K. Holtzman BUILD AN R.o O CAn( 110x gracefully hide the glitches that computer editor arise as you switch from one scene Robert Grossblatt, circuits editor re Hacker News to another. To find out more about Larry Klein, audio editor AuQ. Las More. how you can make your home videos David Lachenbruch look like professional productions, contributing editor Don Lancaster turn to page 33. contributing editor Richard D. Fitch contributing editor COMING HEXT Kathy Campbell, editorial assistant ART DEPARTMENT Andre Duzant, art director THE DECEMBER ISSUE Injae Lee, illustrator Russell C. Truelson, illustrator GOES ON SALE PRODUCTION DEPARTMENT NOVEMBER 2. Ruby M. Yee, production director Robert A. W. Lowndes, editorial production BUILD A PROGRAMMABLE PHASOR PROPERTY GUARD Karen S. Tucker advertising production This high-tech deterrent creates a field of high sound pressure acoustical Marcella Amoroso ultrasonic energy that will send any burglar running! production assistant BUILD A PC BOARD CIRCULATION DEPARTMENT ETCHING SYSTEM Jacqueline P. Cheeseboro A must for making your own boards at home. circulation director Wendy Alanko BUILD THE VIDEO SCENE SWITCHER: Part II circulation analyst Theresa Lombardo We finish up the circuit details and get on to construction. circulation assistant Michele Torrillo, reprint bookstore

CIRCUIT COOKBOOK Typography by Mates Graphics We de -mystify phase -locked loop circuits with plenty of practical Cover photo by Diversified Photo examples. Services Radio -Electronics is indexed in WORKING WITH RELAYS Applied Science & Technology Index How to select solid-state relays and how to design your own. and Readers Guide to Periodical Liter- ature. Microfilm & As a service to readers. RADIO -ELECTRONICS publishes available plans or information relating to newsworthy products, Microfiche editions are techniques and scientific and technological developments. Because of possible variances in the quality and condition of available. Contact circulation depart- materials and workmanship used by readers. RADIO -ELECTRONICS disclaims any responsibility for the safe and proper ment for details. functioning of reader -built projects based upon or from plans or information published in this magazine.

Since some of the equipment and circuitry described in RADIO-ELECTRONICS may relate to or be covered by U.S. patents. Advertising Sales Offices listed RADIO-ELECTRONICS disclaims any liability for the infringement of such patents by the making. using, or selling of any such on page 106. equipment or circuitry, and suggests that anyone interested in such projects consult a patent attorney.

RADIO-ELECTRONICS. (ISSN 0033-7862) October 1989. Published monthly by Gernsback Publications. Inc., 500-B Bi -County Boulevard. Farmingdale, NY 11735 Second -Class Postage paid at Farmingdale, NY and additional mailing offices. Second -Class mail registration No. 9242 authorized at Toronto. Canada. One-year subscription rate U.S.A. and possessions $17.97, Canada $23.97, all other countries $26.97. All subscription orders payable in U.S.A. funds only, via international postal money order or check drawn on a U.S.A. bank. Single copies $2.25. c 1989 by Gernsback Publications, Inc. All rights reserved. Printed in U.S.A. Audit POSTMASTER: Please send address changes to RADIO -ELECTRONICS, Subscription Dept.. Box 55115. Boulder. CO 80321-5115. ,1PA1 ,TheBureau fof Circulation A stamped 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 or photographs while in our possession or otherwise.

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sentially, SMCS will allow any orig- Analytical software inal prerecorded work to be copied indefinitely onto different Analytical software that elimi- blank DAT cassettes, but limits the nates much of the time- and number of digital -to-digital copies money -consuming guesswork in that can be made from the first - designing molds for forming plas- generation copies. The circuitry tic parts is reported by engineers that controls the DAT deck's func- at the GE Research and Develop- tions will be programmed to deter- ment Center at Schenectady, NY. mine whether the music to be The advanced software packages recorded is entering via the re- are used in developing parts made corder's digital or analog inputs by blow -molding and thermo- and to read certain codes con- forming. Containers for milk, tained in the material's subcodes. soda, and other liquids are among All digital recordings and broad- the familiar products made by casts have digital subcode chan- blow -molding. Liners for re- nels that contain their "category frigerators and instrument panels codes" as well as a "copyright for cars are among the products flag." The DAT machine uses a made by thermoforming. combination of the two to tell if The new software was designed GE ENGINEERS, Dr. Horst G. DeLorenzi copying is permitted. If the source primarily for predicting wall thick- and Dr. Herman F. Nied examine test parts and material are identified as ness. "The plastic gets very thin made with the help of the new advanced being protected, an "identification software that makes it possible to simu- where it has a code" of "1,0" is written onto the to stretch lot, and late the molding of a plastic component, there was no way of predicting just using a mold that exists only in the com- copy as it is being recorded; the how thin it would get," says one of puter's "mind." The computer simulation "1,0" code prevents direct digital the engineers. "You'd have to of the part (shown on the screen in the copying from that copy. If the background) shows variations in its wall make a mold and produce a part to source is identified and the mate- thickness, and points up any too -thin find out." parts. rial is not copy-protected, a "0,0" The analysis is made after a decode will be assigned and future signer has generated a computer being used, and the computer per- copying will not be limited. Be- model of a proposed mold. The forms its "thinning" analysis. Spe- cause the technology does not ex- user inputs data that describes the cial algorithms had to be de- ist at this time for the DAT deck to elevated -temperature "stress vs veloped to solve the equations determine if music entering strain" behavior of the plastic used. through the analog inputs is copy - protected, any material recorded via the analog inputs would generate a "1,1" code that would indicate DAT update America (RIAA) in suporting legis- that only one additional digital Last month we reported that lation for a new consumer DAT re- copy could be made from the first- digital audio tape (DAT) decks corder system that allows copying, generation copy. were likely to hit the consumer but limits subsequent reproduc- Besides the EIA-RIAA support, market in the near future, after tion of those copies. That same SMCS is expected meet the ap- gaining recording -industry ap- day, in London, leaders of the in- proval of important consumer and proval thanks to the addition of a ternational recording and con- retailer groups, including the built-in copy -protection device sumer -electronics industries an- Home Recording Rights Coalition, called Solocopy. A few days after nounced a joint recommendation the Consumers Union, and the that issue went to press, two sepa- to governments calling for the im- National Association of Retail rate DAT announcements proved plemention of that system-not Dealers of America (NARDA). The us right-and wrong. Solocopy, but the Serial Copy international group was made up On July 28th, the Electronic Management System, or SCMS. of leading Japanese and European Industries Association's As its name implies, the system electronics manufacturers the Consumer Electronics Group (EIN is a method for controlling "serial" RIAA, and the International CEG) said that they would join the digital copying, which high-speed Federation of the Phonographic Recording Industry Association of pirating operations would use. Es- Industry (IFPI). R -E

4 www.americanradiohistory.com WITH CIE, THE WORLD OF ELECTRONICS CAN BE YOUR WORLD, TOO.

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CIRCLE 60 ON FREE INFORMATION CARD www.americanradiohistory.com VIDEO NEWS DAVID LACHENBRUCH, CONTRIBUTING EDITOR

Ghostbuster. Fifty years after the start of that when the two fields are displayed at the same regular electronic television transmission, time as they are in IDTV-there could be some broadcasters and TV-set manufacturers are about problems. TV stations transmit odd lines (1, 3, 5, to tackle the single most troublesome reception and so forth) and then go back to the even lines problem-multipath, or "ghosts." The National (2, 4, 6, etc.). Progressive -scan IDTV sets Association of Broadcasters (NAB) has proposed rearrange the order of that presentation, deriving to the Advanced Television System Committee additional lines and presenting the lines in (ATSC) a crash program to develop a ghost - numerical sequence. They all use various means elimination system, an idea that has been of compensating for motion that results from enthusiastically seconded by the television - rearranging the timing of the picture elements. receiver industry. Most of the proposed high - Because of the rearrangement of lines, the NAB definition TV systems included ghost complains that in some cases IDTV sets might cancellation, accomplished by various means. The cause distortion-particularly in cases where first anti -ghosting system to go into effect is graphics are superimposed on the picture or in being implemented this fall in Japan with cases of rapid motion, as in ice hockey. In other Clearvision extended -definition TV (EDTV) cases, IDTV might present too good a picture; its broadcasts, but there is no reason why anti - redundant lines appear to show up poor -quality ghosting can't be accomplished on the standard broadcast equipment. Set makers insist that NTSC signal without EDTV or HDTV. there's nothing wrong with their IDTV sets-but The Japanese system uses an invisible the broadcasters want to talk it over. "training pulse" that is broadcast in the vertical blanking interval. It is very inexpensive for Dwindling monochrome. Black -and -white broadcasters to implement, although there are television is nearing the end of the line. In the other anti -ghosting systems that act alone in the first five months of 1989, sales were down 38.1% receiver without a broadcast pilot signal. The from the same period in 1988. For January ATSC will examine all the proposed systems with through May, sales to dealers totaled only 619,000 a view to starting tests as soon as possible-and sets, according to the EIA. That's below the total perhaps instituting an anti -ghosting program for any good single sales month in the 1960's. within the year. Although the system obviously Dealers are quick to say that the slump isn't due would aid broadcasters, the cable system isn't to any lack of customers but to the shortage of immune to ghosts either. Many cable systems sets. With color prices declining and have difficulty in picking up clear signals off the monochrome prices rising due to the scarcity of air. In addition, there's the problem of ghosts picture tubes, the black -and -white TV set now generated internally within cable systems-not certainly appears to be a vanishing breed. to mention direct -pickup ghosts in cities, where the signal reaches the antenna terminals directly 2 -headed VCR. Go -Video, the Arizona from the station as well as from the cable system. company that filed suit against most Japanese Whatever, the ghostbuster will be welcome VCR manufacturers, says it will market a double - nationwide. Let's have it soon! deck VCR by Christmas. (The lawsuits charged that the VCR manufacturers were refusing to sell IDTV problems. While the NAB loves the finished products or parts for the dual decks.) ghostbuster, it's not so sure it likes improved - The double -deck unit, made for Go -Video by definition TV (IDTV) sets. The latest hot products Korea's Samsung, will list at $995 and contain on the TV market, those sets convert interlaced two VHS decks for dubbing and editing. The deck scan to progressive scan, in effect doubling the will have special circuitry to prevent the copying number of lines in the picture. It's very obvious of Macrovision-encoded cassettes. R E 6 www.americanradiohistory.com No matter where you go, Tek's new 222 is a perfect fit.

Introducing Tek's new 222 Digital Oscilloscope. Weighing Plus, the 222 lets you pre -define front-panel setups, and call in at under 4.5 pounds, the new Tek 222 is an ultra -portable, them up with a single button in the field. You can also save 10 -MHz digital storage scope that's perfect for service applications. waveforms in the scope's memory, then transfer them to a PC for So tough, rugged, and totally self-contained, it can go just analysis and hard -copy output when you get back to the shop. about anywhere. And it's incredibly easy to use-even in Best of all, the 222 is yours for only $2350. And that includes extreme conditions. Tek's remarkable three-year warranty Extraordinary capability and reliability at on parts, labor, and CRT a great price. The 222 is a dual -channel Get one to go! Pack a handful of scope that can measure a wide variety power with you wherever you go. To of electronic instrumentation and order your 222, or for a free bro- circuitry. It has rechargeable on- chure, contact your local Tek rep- board batteries with a floating resentative or authorized ground to 400 volts, and distributor. meets tough environmental In a hurry? Call standards. 1-800-426-2200. Téktronix COMMITTED TO E%I:EL LEN,

Copyright .e1988. Tektronix Inc. All rights reserved iHH-9"t Prices subject to change without notice. CIRCLE 92 ON FREE INFORMATION CARD www.americanradiohistory.com Learn to troubleshoot and service today's computer nTstems as you build a fully XT- compatible micro, complete with 640K RAM and powerful 20 meg hard drive Train the NRI Way- and Earn Good Money Servicing Any Brand of Computer

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ASK R -E AsK Radio R -E -Electronics 500-B Bi -County Blvd. Farmingdale, NY 11735

FLASH POWER job done by spending a couple of I spend a good deal of my work bucks on a small photoflash and an time in front of a computer terminal AC adapter. and, because of the way my office is laid out, I can't see the front door AUTOMATIC SEPTIC PUMP while I'm working. Since I'm deaf, Our town sewer drains to the have no way of knowing when some- south, and my home is on a north one is knocking on the door or has slope. I have a septic tank and each entered my office. I'd like to rig up a day I have to manually turn on a strobe light that will flash to alert me switch to pump the liquid up the to the visitor. I've purchased a Xenon hill to the sewer. Is it possible to use Flash Tube, but I don't have any idea some sort of sensor to turn the how to power it. Can you provide me I. CHaosE AN SC,e 1:7/734/ TE pump on automatically every time P,PpPE,Q POIf/ER with a circuit to power and trigger a ,e,477/V6.5- the tank is full? I'd like to have strobe from a 120 -VAC source?-S 2,55 CAREFUL S/NGE indicators to show whether the Anthony, Tulsa, Oklahoma /iOLTi46E 5 4,2E PeESENT tank is full or empty, when the AT T//E .FLA..S// 72/.9E Although there are several ways pump is operating, and so on. I

to trigger a flash tube, all involve FIG. 1 can't use relays because the tank generating high voltages. Com- produces explosive gas.-M. mercial flash units either step up If you do build your own circuit Craghead, .letmore, Kansas the AC line voltage to whatever to power the tube, be very careful There are several commercial voltage the tube needs or use a putting it together. Not only are systems available that will more switching supply to get the re- you playing around with the line or less do the job you're describ- quired AC voltage from a low - voltage but you're also stepping it ing. The problem with most of powered DC supply. The latter is up to over 200 VAC. Make sure ev- them, however, is that they use a the basis of most of the battery - erything is properly insulated, and float system with a mechanical powered flash units used in pho- be sure to put a fuse on the line. switch. That means that there's tography. While you're free to get the job the possibility of a spark near the While it's certainly possible to done any way you want, re- tank on the one hand, and, on build a circuit to drive the tube, it's member that the original idea was the other, having to do the worst not really worth it since commer- to let you know when someone is job in the world if (or, more cor- cial photographic flash units are entering the room, not learning to rectly, when) the float sinks. available for less than the total build a power supply for the You said that you already have price of the parts needed to build strobe. It's a lot easier to get the an SCR-triac setup to control the one. If you're really into building your own stuff, you can use the NON-LATCH/N& L,RTCH/N6 circuit shown in Fig. 1 as a starting V fV point. The 200-300 VAC can be gotten from a standard step-up transformer. If you can't find one of them, you can try a transformer - based voltage converter that lets 2 you use 120 -VAC appliances in º countries that have 220 VAC. Make sure you get a converter that's built around a transformer f V CAN BE GYHATEVER Vc7L7--.4GE /5 and not one that uses diodes. Just E4u/2EO TO E1VS.f'G>/zE T,yE ,2EL,4Y <.Z4 V MAX). CHOc7.SE 76 /t74TCH vef747-.46_ use it backwards as a step-up ó oc transformer. FIG. 2

12 www.americanradiohistory.com COAX ADAPTER MT Create any adapter in seconds Make all combinations of BNC, TNC, SMA, N, UHF, Mini -UHF, F and RCA The TPI 3000A kit contains male and female connectors of all 8 types, and 6 universal interfaces. Simply screw any combination of 24 connectors to one of the interfaces to create the desired adapter. $150. TEST PROBES INC. 9178 Brown Deer, San Diego, California 92121. Call toll -free for catalog: 1-800-368-5719.

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www.americanradiohistory.com pump, so the only piece you're in the septic tank, you should cuit in a weatherproof enclosure, missing is a circuit to trigger the choose a metal that won't be af- along with a transformer and rec- system. What you're looking for fected by any of the corrosive liq- tifier, and bury it in the ground is a liquid -level detector that uids found there. The cheapest next to the power leads for the meets the requirements of low alternative is to make the probes pump itself. The transformer - voltage and minimal current from stainless steel, but any rectifier circuit can tap power draw. other conductive material that from those leads, so that you can Figure 2 contains two simple isn't affected by corrosive liquids power the circuit locally. detector circuits that should can be used. The circuits will drive SCR's or work perfectly for you. Believe it Try to locate the detector cir- relays. And while I do under- or not, the most critical part of cuit fairly close to the septic tank stand your concern about ex- the whole thing are the probes. to keep the probe length as short plosive gas, the circuitry doesn't Since you're burying them down as possible. You can put the cir- have to be in the tank itself, so there's no reason why you can't use relays. Whatever you use to control the motor, make sure that it can handle the amount of OPTOELECTRON/CS power needed by the pump. R-E RE -WIRING I've recently bought a house in the country, and I plan on rewiring it because the original wire is quite old. Since the wiring is buried in the walls, I need some way of locating them. I'd like to be able to do that without knocking lots of holes in the walls. Is there some easy, inexpensive, way to do that?-B. MacDon- nell, New York, NY If you hunt through lots of magazines and catalogs, you'll probably find some expensive piece of equipment that can locate wires buried in the walls. But there's another way to do the job that's just You Have Counted on Us for 15 Years as accurate, costs nothing, and uses equipment that you probably You have counted on OPTOELECTRONICS id more and more of you are counting on Hand Held Frequency Counters to be the us, technicians, engineers, law enforcement have around the house anyway. best quality, to be affordable and reliable. officers, private investigators, two-way radio All you need to find the wires is We have been there for you with Frequency operators, scanner hobbyists, and amateur Counters that are compact and ultra sensitive radio operators, just to name a few. an old, noisy, electric appliance and a small transistor radio. The Hand Held Series Frequency Counters and Instruments appliance can be any motor -driven MODEL ,,,1; . CCB_.. device such as a hair dryer, drill, FH r, -t RANGE: 10 Hz 1 MHz 10 MHz 10 MHz 10 MHz TO 2.2 GHz 1.3 GHz 2.4 GHz 550 MHz 1.8 GHz food processor, and so on. The APPLICATIONS General Purpose RF Microwave Security Security only requirement is that it have a Audio -Microwave motor with brushes, PRICE $219 $169 $189 $299 $99 and the more SENSITIVITY it arcs and spits, the better it is. 1 KHz < 5 my NA NA NA NA The reason you want a noisy 100 MHz < 3 my < 1 mv < 3 my < .5mv < 5 my 450 MHz < 3 my < 5 my < 3 my < 1 mv < 5 my motor is that it generates inter- 850 MHz < 3 my < 20 my < 5 my NA < 5 my ference that can be a 1.3 GHz < 7 mv < 100 mv < 7 mv NA < 10my picked up on 2.2 GHz 30 mv NA < 30 mv NA < 30 my portable radio (or any other radio ACCURACY ALL HAVE +1- 1 PPM TCXO TIME BASE. or TV for that matter). Turn on the Ail counters have 8 dig t red 28" LED displays. Aluminum cabinet is 3.9" H o 3.5" x 1". Internal Ni -Cad batteries provide 2-5 hour portable operation with continuous operation from AC line charger/power supply supplied. Model appliance and run the radio across CCB uses a 9 volt alkal ne battery. One year parts and labor guarantee. A full line of probes, antennas, and accessories the area of the wall where you is available. Orders to U.S. and Canada add 5% to total ($2 min. $10 max). Florida residents, add 6% sales tax. ex- COD fee $3. Foreign o ders add 15%. MasterCard and VISA accepted. pect to find wiring. The louder the Orders to U.S. and Canada add 5% to total ($2 min. $10 max). Florida residents, add 6% sales tax. COD fee $3. noise Foreign orders add 15%. MasterCard and VISA accepted. from the radio, the closer you are to the wires. Don't be under the impression OPTOELECTRONICS INC. that this is just a juryrigged way to 5821 N.E. 14th Avenue Fort Lauderdale, Florida 33334 1-800-327-5912 FL (305) 771-2050 FAX (305) 771-2052 get the job done. Most of the dedicated equipment that's designed to find buried wiring works on ex- CIRCLE 185 ON FREE INFORMATION CARD actly the same principle. R-E

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NUCLEAR -WASTE MANAGEMENT generated would have to be super- goes back to 1945, when I de- I have been working in the elec- vised for a period of time that will signed and built my own 10 -inch

tronics field for over 50 years, and be much longer than any govern- receiver. I also designed and built have been a reader and subscriber ment has held power-indeed, my own color receiver in 1954. I am of Radio -Electronics for many longer than recorded history-we probably more aware than most years. I've never written to any shudder-Editor people of the shortcomings of the publication before, but now I feel NTSC system. I am also aware of compelled to do so. SELLING SOLAR POWER SHORT what a wonderful achievement it In the August 1989 issue, Don I found Don Lancaster's "Hard- was, more than 35 years ago, to Lancaster seems to have been car- ware Hacker" column concerning come up with something that ried away by the more radical ecol- cold fusion (Radio -Electronics, Au- good. ogy nuts. His diatribe against gust 1989) to be interesting, but I As far as HDTV is concerned,

nuclear power is a very short- take exception to his view on solar unfortunately, I have a pessimistic sighted condemnation of one of cells. viewpoint, which is not helped by

the cleanest sources of power His analysis of the hidden costs the many competing systems. I am available today. His idea for a is wrong, since he is basing it on completely able to accept that ex- waste -disposal site is too face- the premise that it would be too cellent HDTV systems can be de-

tious. Some people feel that solar costly for a utility or a small power signed and built. I can even power would be a better source of supplier. Photovoltaics are ap- believe that it will be possible to power, but he condemns that out plicable to homeowners, not util- agree upon one system, as was of hand. ities, so costs for real estate and done with NTSC. I do not believe, I feel that what is needed to major support structures do not however, that it can be sold to a make nuclear power really prac- enter into the picture. (And the mass market. tical is very careful monitoring of financing is considerably lower for If one goes into any appliance all plant construction-no short those free cells he mentioned.) store that has operating TV sets on cuts to save money. Then, for The efficiency of modern cells is display, one is amazed by the waste storage, the federal govern- more like 14%, with stacked cells dreadful quality of the pictures on ment could locate an isolated bowl yielding 28-30%. I understand that many of those receivers. That is in the western mountains and there is a photovoltaic that uses a usually the result of incompetent maintain well -supervised facili- unique approach that can obtain adjustment by the sales person- ties. One day, some bright scien- efficiencies between 40-60% nel, and is often made worse by tist will figure out a way to make P.S. Do you need my full address poor incoming signals. Since the good use of the waste. Then, all for my truckload of "free" solar appliance store is in business to too soon, there will be a shortage cells? sell TV sets, one must conclude of such material! It has happened JOE ZUIS that the poor picture quality does before. Consider what happened Brockton, MA not bother prospective customers. to the left -over sludge from early (If it did, the store would take oil refineries: Someone processed HDTV: A PESSIMIST VIEWPOINT steps to improve it, to avoid loss of it and got paraffin. Today, very little I have been very interested in sales.) waste is left to throw away. That is your recent articles (Radio -Elec- One can observe the same thing the way to go-instead of con- tronics, January and February 1989) in many people's homes. The pic- demning things out of hand, think concerning High Definition and ture will often have grossly wrong constructively! Improved Definition TV (HDTV color, or other major defects, EWALD HANSEN and IDTV). which could be greatly improved White Plains, NY I recently retired after a lifetime by simple adjustment. However, spent as a professional engineer in most people do not notice, or care Perhaps you're correct. But electronics, mostly military and about, the poor picture quality. when we consider that the waste space related. My interest in TV A minority of people, myself in -

16 www.americanradiohistory.com Now Testing Is Seven Times Easier.

1. End Blown Fuses. bleed -off is heard loud and clear with and Audible Readout allow you to spend less time fiddling with your The new 200 Series multimeter is the 200 Series' Audible Readout. protected from excess voltage or surges meter. 5. Find Logic Stuck-Ats. with a self-resetting fuse. FEATURES 222 22 Using standard leads, a fast Logic Audible Readout 2. Keep Your Eyes On Your Work. Pulse Detector lets you easily detect Logic Pulse Detector Quickly probe a circuit board listening pulses down to 5Ons. Fast Auto -Ranging for audible tone changes that pinpoint Self -Resetting Fuse the problem without glancing at 6. Adjust Voltage Levels. Auto -off Battery Saver DC Voltage Accuracy 0.5% 0.25% the LCD. When adjusting audio or video response, an audible tone that changes Warranty 2 years 2 years Price $129.00 $149.00 3. Detect Intermittents. pitch as measured signals increase or Hear a distinctive crackling sound decrease permits faster and easier The 200 Series. Multimeters that when an intermittent occurs. adjustments. take the work out of work. Call or write for complete information. 4. Find Dead Capacitors. 7 Stop Third Hand Problem. 1-800-227-9781 Inside California. Capacitor voltage build-up or Tilt stand and Skyhook;"auto-ranging, 1-800-854-2708 Outside California. 63t, Bckman Industrial - An Affiliate of Emerson Electric Co. Instrumentation Products Division 3883 Ruffin Road, San Diego, CA 92123-1898 © 1989 Beckman Industrial Corporation (619) 495-3200 FAX (619) 268-0172 TLX 249031 Specifications subject to change without notice. 17 CIRCLE 98 ON FREE INFORMATION CARD www.americanradiohistory.com ACE TROUE Find trouble fast with the new 100 MHz

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21 www.americanradiohistory.com Be an FCC cluded, do care about picture which HDTV will provide. Don't quality. When I watch TV, I often worry. It will sell.-Editor LICENSED find myself paying a lot more at- ELECTRONIC TECHNICIAN! tention to the picture quality than DE -MYSTIFYING MIDI to the programming. (Perhaps that I enjoyed reading your articles is just as well, given the content of on MIDI. I've been interested in many of the programs!) However, knowing more about the subject, ` ;:s'`.-`- HDTV will only be economically but I always found the explana- Earn up to $30 an hour feasible if it can appeal to a truly tions to be too complicated. The and more! o mass market. I do not believe that article, "Musical Instrument Digi- oo mass market exists. People will tal Interface," (Radio -Electronics, Learn at home in spare time. buy gimmicks and convenience August1989) has been a great help, Fri\ No previous experience needed! <,l ! features-remote controls, VCR's, as it was both informative and- No costly School. No commuting to class. simultaneous viewing of more The Original Home -Study course pre- two or important-it was also very pares you for the "FCC Commercial Radio- more pictures, etc.-but most easy to comprehend. telephone License". This valuable license people do not really care about MATTHEW KREVAT is your "ticket" to thousands of exciting quality. Brooklyn, NY jobs in Communications, RadioTV, Micro- That is wave, Computers, Radar, Avionics and also evident if one re- more!- You don't need a college degree to members the failure of the so- ALTERED AUDIO AMP qualify, but you do need an FCC License. called 1,000 -line high -definition The March 1989 issue was up to No Need to Quit Your Job or Go To School system that was broadcast in the Radio -Electronics' usual very high This proven course is easy, fast low and Paris, France region for several standards. I especially enjoyed the cost! GUARANTEED PASS - You get your years. TV article FCC License or money refunded. Send for sets that use the VIRS entitled "High -Powered Hi- FREE facts now. MAIL COUPON TODAY! signals broadcast by major net- Fi Audio Amp for Your Home or works to adjust the receiver con- Car." commanD PRODUCTIONS What FCC LICENSE TRAINING, Dept. 90 tinuously, largely overcoming caught my eye was the P.O. Box 2824, San Francisco, CA 94126 many propagation defects, have power converter used to step up Please rush FREE details immediately! not caught on. That is despite the the voltage from 12 volts to 75 volts NAME fact that they can and do often for the final stage (page 53). Wind- ADDRESS CITY STATE ZIP considerably. improve quality at a ing that transformer may prove dif- very low cost. Stereo TV sound has ficult. (Of course, you can always been much less than a great com- break down and buy one, but that mercial success; many receivers isn't as much fun.) If You Fix VCR's, that do use it employ dreadful My alternative method, shown loudspeakers. in Fig. 1, borrows a page from the Ask Yourself Improved definition, using pres- old-time radio power supplies ent-day NTSC signals, has some used in cars in the 1920's and '30's. These Questions very severe limitations; but it has The heart of the supply is two Q Are Most VCR Problems Mechanical? the overwhelming virtue of being DPDT relays that are rated at 5 A Yes, most agree more than 3 out of 4 possible without a truly mass mar- volts. You might have to fool with VCR problems are due to a mechanical ket. A market of a few hundred some of the values to get it to work malfunction. thousand IDTV receivers per year properly, but the design is very for- Q Are There Universal Test Tools Available would make it commercially via- giving, and if you know your P's Or Do You Have To Buy All The Different Tools Shown In Service Manuals? ble. HDTV needs a market of at and Q's with a VOM you might not A TENTEL provides easier to use, universal, least 10 million receivers per year, need a scope. more powerful gauges than all factory in addition to a single agreed - Each relay is wired as a free -run- tools combined. upon system and a very large in- ning astable oscillator, and be- Q What Mechanical Measurements Should vestment by broadcasters. cause you can just about pick the Be Made To Properly Check Out A VCR? I'm sorry to have to take this pes- coil resistance you like best, get- A Hold back tape tension, tension servo simistic viewpoint, but I fear it is a ting the right value for the com- check, reel table heights, carriage align- very valid one. mutating capacitor is not a real ment tape guide height take up torque, restoring torque, brake torques, FF/REW L.D. THOMAS problem. torques & video head wear. Georgetown, DE Note that this commutating capacitor is made from 100 Just released 68 minute the two NEW- IDTV is already a limited com- µF electrolytic capacitors with the Video Training Tape covering over mercial success. North American IN4001 diodes across them. This 28 mechanical VCR tests and Philips, for one, has measurements been selling combination simulates a non - $2495INTRODUCTORY more IDTV sets than they can man- polarized (NP) capacitor. Note that PRICE Shipping Included ufacture. Roughly 40 percent of all the cathodes of the diodes, and TV's being sold today are stereo the positive (+) ends of the capac- Neel ' TENTEL Corporation equipped. That's not unsuc- itors face one another. aCe55. 4475 Golden Foothills Pkwy cessful. Wait until sports fanatics The frequency of oscillation is Pa El Dorado Hills, CA 95630 see the Super Bowl on a wide usually about 1 kHz, (800) 538-6894 / (916) 939-4005 which causes rcdaonal screen with high -quality audio, the relays to hum faintly. That CIRCLE 189 ON FREE INFORMATION CARD 22 www.americanradiohistory.com SD .C1 3 50n,. Woen performance t price really count.. //rv /A1440 / rx z ) /GV Rvz }41- OP/>T RYSTEK RYSTALS -1 /00/cc.F 25v z5V The pulse al dependable c-omm.nttabon%

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SO fi. SO 12 sw f"- sw So V /OOO, . r ^-712V SO V /N54L00 QUARTZ CX3) CRYSTALS/OSCILLATORS FOR /OOC{µ..= ELECTRONIC - INDUSTRIAL ,5-O V a Micro -Processor Control Computers/Modems Test/Measurement Medical FIG. 1 COMMUNICATIONS - REPLACEMENT Mobile/2-way/Channel Elements humming is usually not very loud, A series of articles titled "Annals Pagers Marine and if the circuit is used in a car, it of Radiation" recently appeared in Aircraft 12, 19, and June 26 Telemetry can be placed under the hood or the June June Monitors/kanners in the trunk. issues of the New Yorker maga- PARSONS zine. Please look that series of arti- AMATEURS JIM CB Rapid City, SD cles over and, if you think it is Hobbes! warranted, recommend it to all Experimenter RESPONSE FROM THE RIGHT your readers. I feel that everyone and who is planning a career in the COST EFFECTIVE Please stick to pure science MODERATE PRICING technology in your "Letters" col- electrical field, those already in FAST DELIVERY umn. Please don't print letters the the field, and every young person like of Paul Schick's on HDTV (Ra- who is planning to start up a home dio -Electronics, July 1989). and a family should be aware of the We get enough sour grapes extremely valuable information is in those articles. from the liberal air -heads in the that presented Replacement crystals Catalog editorial pages of our newspapers. I was exposed to heavy doses of Those kinds of statements have RADAR microwave radiation dur- custom Made Crystals Catalog passed off as ing my many years in the Navy, and their hidden agenda The Pulse of Dependable Communications tongue-in-cheek humor. I recently had a brain tumor re- Crystek Crystals otters their new e poye FREE catalog of urygals and oscillators. Offering statrol-the-art crystal components That kind of garbage is out of moved. Reading those articles manufactured by the latest automated technology. Custom designed or "off the shelf,"Crystek meets the need, worldwide. place in a prestigious magazine made me wonder. Write or call today! such as Radio -Electronics. ROY A. NORMAN DONALD C. ROSS LCDR USN, Retired San Jose, CA Brunswick, GA CRYSTEK CORPORATION DIVISION OF WHITEHALL CORPORATION

2351/2371 Crystal Dr. Ft. Myers, FL 33907 RECOMMENDED READING P.O. Box 06135 Ft. Myers, FL 33906-6135 TOLL FREE 1-800-237-3061 I have been a subscriber to Ra- We have read those articles and (813) 936-2109 - TWX 510-951-7448 dio -Electronics for a long time. I are very concerned about some of av®-x served in the U.S. Navy for 30 the issues they raised. We feel that years, both as an enlisted man and they should be required reading sEavvFcx as an officer, but always in some for not just some people, but for field of electronics. everyone.-Editor CIRCLE 69 ON FREE INFORMATION CARD 23 www.americanradiohistory.com EQUIPMENT REPORTS

do point out the versatility of the AR -2515. ACE Communications Alternatively, in search mode, the scanner can be used as a con- AOR AR -2515 ventional receiver. Tuning can be Communications accomplished by direct -frequency keypad entry, turning the rotary Receiver tuning knob, or pushing up or down tuning buttons. Each click of the tuning knob, or each push of One radio for scanner buffs the tuning buttons, changes the and SWL's! receive frequency by a user -selected increment of 5, 10, 12.5, or CIRCLE 42 ON FREE INFORMATION CARD 25 kHz. The receiver is built into a compact gray case that measures about SHORTWAVE LISTENERS AND SCANNER (WFM) and Narrow -band FM 7 x 5-1/2 x 2-1/2 inches (although enthusiasts have always been di- (NFM). it's not really rectangular). The vided into two camps. One is in- The memory capabilities of the front panel, which measures terested in DX-ing and in getting receiver are impressive. Sixty-two about 3 x 5 inches, tilts upward news and views from around the banks of 32 frequencies each pro- and is crowded with 23 pushbut- world. The other is looking for the vide a total of 1984 scannable fre- tons, three rotary knobs, an LCD faster -paced excitement that quencies. Any number of banks frequency display, and an LED sig- comes from hearing real-time ac- can be linked for scanning. So, for nal -strength meter. Despite the tion on the local police, fire, and example, you can scan one band crowded appearance, the controls other public-service bands. But a of 32 frequencies, or you can link are surprisingly easy to use. new piece of equipment may bring all 62 banks and scan through the the two camps closer together: almost 2000 frequencies in memo- Computer interface the AOR AR-2515 communications ry. An additional 18 banks are pro- One of our favorite features of receiver from ACE Communica- vided for search pairs; banks 63 the AR -2515 is its computer inter- tions (10707 East 106 St., Indi- through 79 can contain the upper face. The receiver can communi- anapolis, IN 48256). It is one of the and lower frequency limit for cate with any personal computer few receivers that gives the short- searching out new and unknown that offers an RS -232 interface. wave listener the frequency frequencies that are in use in your Rates of 300,1200, or 9600 baud are coverage and performance he de- area. supported. While ACE does have a sires, while delivering speed, The scanning speed of the re- communications package avail- coverage, and memory capability ceiver is, at best, about 36 chan- able, any general communications to the scanner buff. nels per second. That decreases if software is adequate. The AR-2515 boasts a frequency the frequencies in a scanning bank The interface allows you to con- coverage from 5 MHz to 1500 MHz, are widely separated, or if mode trol all of the functions of the re- which includes international changes are required, etc. If ceiver from your computer key- shortwave broadcasts, amateur you're willing to ignore the de- board, except for volume and bands, TV audio, FM broadcasts, crease in scanning speeds, you squelch. You can upload complete VHF aircraft, various government can create some interesting and banks of frequencies, change op- communications, NOAA weather useful banks. For example, we erating modes, switch scanning broadcasts, VHF aircraft, cellular filled one bank with some fre- banks, and even turn on the LCD telephone, and more. (We should quencies in which we were often light. point out that reception of various interested. It included the local Perhaps the most useful at- frequencies covered by the re- National Weather Service broad- tribute of the communications ca- ceiver, including cellular frequen- casts, WWV shortwave broad- pability is that it allows the receiver cies, is forbidden by the Electronic casts, and a couple of local FM to send important information to Communications Privacy Act of broadcast stations. While those the computer. Our favorite com- 1986.) Three operating modes are might be considered to be un- mand puts the receiver in an auto - supported: AM, Wide -band FM, usual scanner frequencies, they continued on page 32 24

www.americanradiohistory.com In NORM mode, the PSA-65A displays a frequency spectrum, being AVCOM PSA-65A calibrated when the VAR SPAN knob is in the CAL position. As it's rotated Spectrum Analyzer toward ZERO SPAN, the observed spectrum segment on the CRT expands horizontally about the cen- An inexpensive, quality ter frequency, narrowing in band- spectrum analyzer from 2 width. The ZERO SPAN+XSC SETTING MHz -1 GHz. OF THE VAR SPAN knob is an ideal, because the time waveform on the CIRCLE 43 ON FREE INFORMATION CARD CRT is never a pure sinusoid, since the horizontal SPAN control has a finite nonzero bandwidth filter for VERY LIKELY, MANY OF YOU HAVE AL - That would require having two each setting (more below). ways wanted a professional spec- separate tuners, one to be swept The AUDIO mode automatically trum analyzer, whether for trou- through the observable spectrum, gives a ZERO SPAN display. The bleshooting, or experimentation. and the other tuned to the center MOMEN mode momentarily does However, every time you've frequency. so, to let the user alter the center looked at a catalog and seen prices An earphone jack is provided TUNING frequency easily. In NORM that start in the $10-20K range, (AUDIO OUT), and an AUX jack is for mode, there's a 0.5 second lag be- your jaw drops. Unless you're in a present and future optional ac- tween moving the TUNING knob, large corporate firm with mega- cessories. The SWEEP RATE control and the corresponding update of buck budgets, you've probably varies the speed of the sweep -rate the LCD. had no chance of getting one until generator. For maximum accuracy In the AUDIO and MOMEN modes, now. in vertical amplitude measure- no such lag exists, and any TUNING With the Model PSA-65A 2 ments, the sweep is set as slow as knob rotation is instantly reflected MHz -1 GHz Spectrum Analyzer possible. A BNC jack is used for RF on the LCD. The center frequency from AVCOM Corp. (500 South - INPUT from 2 MHz -1 GHz range, is controlled by two potentiome- lake Blvd., Richmond, VA 23236), and a maximum power of 15 dBm, ters, one a 10 -turn version for main that problem is over. The basic or 31.6 mW. TUNING, and a single -turn FINE TUNE cost is $2,675, and many reason- control. The FINE TUNE appears to ably priced accessories, like an FM Vertical amplitude controls have a range of about 7 MHz, but is demodulator ($185), high-perfor- The CRT is located in the upper asymmetric and nonlinear in mance attachable log -periodic an- left of the front panel, and the grat- effect. tennas (about $239), and carrying icule is calibrated vertically in dBm For each horizontal SPAN setting, case ($89.95) are available. At 11.5- and dBmV, and horizontally in there's a nonzero filter bandwidth x 5.5- x 13.5 inches and a weight dBmV. Those two units are dB rela- resolution, which gives rise to the of 18 pounds, it's as portable as a tive to a milliwatt (mW) and a milli- time effects observed at ZERO SPAN standard portable oscilloscope. volt (mV), respectively. The (discussed shortly). The resolution PSA-65A has VERTICAL POSITION and is 3 MHz at 100 MHz/div, 1 MHz at General controls and jacks REFERENCE LEVEL knobs, and a 50 MHz/div, 300 kHz at 10 MHz/div, The PSA-65A has numerous, VERTICAL SENSITIVITY Switch to select 150 kHz at 5 MHz/div, and normally convenient, and well -labeled con- between 10 dB/div or 2 dB/div (for 75 kHz at either 1 MHz/div or 200 trols. They're all on the front pan- both dBm and dBmV). The kHz/div. The user can also opt for el, and grouped according to reference level allows vertical ex- an additional 10 kHz filter for the function in a color-coded gray - pansion by vertically moving the 200 kHz/div setting, if desired. and -white format. The PSA-65A is signal -noise floor, and is calibrated One good way to observe the powered by 120- volt, 60 -Hz AC, with the vertical sensitivity set to 10 effects of those filters is by observ- but can run using an internal gel - dB/div, but not 2 dB/div. ing a TV station spectrum. The AM cell battery with recharger. The video is always 4.5 MHz below the POWER switch has BAT, STANDBY, and Horizontal and tuning controls FM audio. If you center the video LINE positions. The battery charger The main function switch on the on the CRT with the VAR SPAN con- (BAT CHG) can operate in any POWER PSA-65A is ZERO SPAN, which deter- trol set to CAL, and then rotate it to SWITCH position, and needs about mines whether the instrument is ZERO SPAN, you'd see the actual three hours to charge sufficiently operating in AUDIO, NORM, or time waveform, just as if you were for prolonged use. MOMEN mode. In AUDIO mode, the using an oscilloscope. The AUDIO DEMOD pot- PSA-65A displays an AM or FM That waveform would be com- entiometer is the volume control broadcast by quadrature detec- pletely visible as the VAR SPAN is for listening to AM or FM broad- tion, at the frequency indicated on rotated toward ZERO SPAN. In the casts, and has a built-in SPST ON/ the 4 -digit CENTER FREQUENCY MHZ CAL position, you'd see the spec- OFF switch. However, the PSA-65A LCD. The quadrature detector is trum, but possibly also see a spu- won't let you observe a spectrum mainly for FM, but also demodu- rious representation of the time and listen to audio simultaneously. lates AM intelligibly. continued on page 32

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The model 408 video test signal generator costs ANALOG/DIGITAL STOR- $3,395.00.-Leader Instru- AGE SCOPE. With the help ments Corporation, 380 Oser of custom IC's, the Avenue, Hauppauge, NY Tektronix' 2232 portable 11788. analog/Digital Storage Os- cilloscope (DSO) delivers a 16 -BIT CONVERTER 100-MS/s sample rate and a BOARDS. Designed to pro- 100 -MHz bandwidth. Its vide a full -featured, low- proprietary peak -detection cost alternative to custom or capability allows for glitch microcomputer -based sys- capture as narrow as 10 ns at tems, MetraByte's MBC- all sweep speeds, including GAD and MBC-DAC plug-in dual -channel operation. daughter boards for Macin- The scope has several fea- tosh II's and SE's offer high - tures designed to make it resolution data sampling easy to use, including on- and conversion. screen readout of scale fac- The MBC-GAD performs tors and cursor measure- a 16 -bit A/D conversion at a ments of voltage and time. rate of 16,000 samples per Bezel buttons provide quick second, with a resolution of access to saved reference CIRCLE 10 ON FREE INFORMATION CARD 1 part in 65,536 and 0.003% waveforms and the full measurement accuracy. The range of menu selections. sampling, the DSO is a ver- library of saved waveforms. differential analog input. Trigger-level readout allows satile general-purpose in- Known -good waveforms may be configured for volt- the user to set the voltage strument. Its analog opera- can be stored for reference, age ranges of ±2.5, ±5, or level for the trigger point tion allows the display of and unknown waveforms ±10 volts; 0 to 5 volts; or 0 and read it directly on complex waveforms such as can be captured in the field to 10 volts. The analog input screen, which can save a lot video signals and realtime and stored for later analysis. is accessible via a standard of time in single -shot wave- update of changing signals. An RS -232-C interface op- RCA phono connector or a form -capture and "babysit- Digital capabilities include tion lets such waveforms be 10 -pin ribbon -cable con- ting" (unattended monitor- waveform storage, peak de- transferred by modem. nector. Two MBC-GAD'S ing) applications. For added tection, and pretriggering. The 2232 portable digital can be installed on one triggering flexibility, both When troubleshooting digi- storage oscilloscope has a motherboard to create mul- low- and high -frequency re- tal devices, the sampling list price of $5,495.00. The tichannel subsystems. ject capabilities assure a sta- rate allows the capture of RS -232-C and GPIB interface ble, usable trigger even on single -shot events up to 10 options cost $300.00 noisy or complex signals. MHz. With the DSO's ability each.-Tektronix, P.O. Box With both analog and digi- to store as many as 29 wave- 1700, Beaverton, OR 97075; -1 1'4'1' tal capabilities, and 100-MS/s form sets, users can build a 1-800-426-2200. - 4- 9. 4a

VIDEO TEST GENERATOR. with an LCD readout is used The model 408 gen -lockable to set up channel frequen- NTSC video test signal gen- cies and video -signal -driven erator from Leader Instru- specifications. Control of ments provides over 80 test key video -signal levels- in S - patterns composite; such as sync, burst, lumi- CIRCLE 12 ON FREE VHS; RGB; and Y, R -Y, and CIRCLE 11 ON FREE nance, chrominance, and INFORMATION CARD B -Y output formats with RF INFORMATION CARD setup-is provided, along channel coverage of all with RF -frequency selec- The MBC-DAC provides broadcast and cable chan- crosshatch are just a sam- tion. As many as 100 sets of two independent, 16 -bit nels. Multiburst, video pling of the available test video -level specifications analog -output channels, sweep, SMPTE color bars, patterns. and channels can be stored which are capable of pro- modulated and unmodu- A menu -driven, multipur- in memory and instantly re- cessing data at 100,000 sam- lated staircase, raster, and pose data -control board called as needed. ples per second to voltage 26

www.americanradiohistory.com I II

accuracies of 0.006%. The input -selection capability of tion to as many as five dif- 0 -dB or 20 -dB output. The voltage range of each out- stereo amplifiers. ferent input sources. It is instrument features 1 -kHz put channel is fixed at ±10 packaged in a fully - internal modulation, and in- volts, and the channels are shielded, black ABS -plastic put voltage is less than 50 accessible via a 10 -pin rib- housing, and features silver- mV. bon -cable connector. plated switch contacts, dual Both daughter boards can tape outputs, and a tape - be driven from programs monitor switch to allow written in high-level lan- monitoring of either record- guages, such as BASIC, PAS- er. Stereo cable is included. CAL, C, or FORTRAN. When The AX 101 CD phono -in- used with MetraByte's CIRCLE 13 ON FREE put adapter and the AX 100 MBC-625 motherboard, INFORMATION CARD auxiliary selector cost they provide high-speed, $89.95 and $29.95, respec- high -resolution data -ac- The phono -input adapter tively.-Johnson Electronics CIRCLE 14 ON FREE quisition capabilities for allows amplifiers that do not Labs, Inc., 409 Angus Blvd. INFORMATION CARD Macintosh users. have a CD or auxiliary input #29N, Warner Robins, GA The MBC-GAD 16 -kHz A/ to accept a CD player-or 31088. The SG -9500 signal gener- D converter and the MBC- any other auxiliary device- ator with built-in frequency DAC 100 -kHz D/A converter through the magnetic pho- SIGNAL GENERATOR/ counter costs $349.00.-Ele- cost $550.00 and $475.00, re- no input. Its passive -circuit COUNTER. Combining a nco Electronics Inc., 150 spectively. The MBC-625 design minimizes noise and signal generator and a fre- West Carpenter Avenue, motherboard costs distortion. The AX 101 CD quency counter in one unit, Wheeling, IL 60090. $1,290.00.-MetraByte Cor- features a selector switch Elenco's SG -9500 can gener- poration, 440 Myles Stand- for CD or phono operation, ate RF frequencies from 100 PC THUMBSCREWS. A vari- ish Boulevard, Taunton, MA RIAA response accuracy to kHz to 150 MHz and can ety of thumbscrews from PC 02780. within 1 dB, and chrome - measure external frequen- Pro are custom -sized to fit plated housing with re- cies up to 150 MHz. Ac- XT's and AT's and make it AUDIO EXPANDERS. The AX movable mounting tabs for curacy is ± count/±1 digit, easier for PC users to get in- 101 CD phono -input adapter easy mounting. and the RF output is 100 -MV side their computers. and the AX 100 auxiliary se- The AX 100 enhances am- RMS, up to 35 MHz. A Thumbytes, Thumbits, and lector from Johnson Elec- plifiers with limited input switch with fine -adjustment Thumbles eliminate the tronics Labs expand the capability, increasing selec- control lets the user select need for the usual assort -

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There are other digital readout oscilloscopes, but none of Other time -saving features include exclusive ECL sync circuits them completely eliminate graticule counting and calculations that allow you to lock quickly onto waveforms up to 100 MHz. Plus, like the SC61 Waveform Analyzer. The innovative, time -saving with 3000 volts of input protection, you never have to worry about an AUTO-TRACKINGTM digital readout automatically gives you every expensive front end repair job. waveform parameter you need for fast troubleshooting. Call 1-800-SENCOR E to find out more about what the SC61 The SC61 Waveform Analyzer is a triple patented high can do for your service business. In Canada call 1-800-851-8866. performance scope that provides you with a digital LCD read-out of all key waveform parameters (DC volts, peak -to -peak volts, and NCOR frequency) at the push of a button, and all with one probe connection. 3200 Sencore Drive, Sioux Falls, SD 57107 100% American Made CIRCLE 181 ON FREE INFORMATION CARD 27 www.americanradiohistory.com ment of nutdrivers, slot - easier to remove cards. chairs the Society of Motion the videodisc player. and Philips -head screw- They are also sold in sets of Picture and Television The disc's test features in- drivers, and nuts and five. Knurled grips make it Engineers (SMPTE) Working clude instructions far ana- screws used to service per- harder to lose screws inside Group on Monitor Calibra- lyzing viewing -device quali- sonal computers. Color -co- the computer. No tools are tion, which is responsible ty along with specific test ded plastic caps are mated needed in order to access for setting NTSC standards signals for the individual to screws, resulting in dura- switches or jumpers after for picture quality. The vid- display parameters that ble thumbscrews that are installation. eodisc was produced in D1, combine to form a good pic- available in an array of sizes Thumbytes and Thumbits the 4:2:2 component digi- ture. Comprehensive cal- and lengths for convenient each cost $5.00 per set of tal -video format that is the ibration instructions are replacement of slide -top five; Thumbles cost $10.00 most advanced recording provided, along with the and adapter -card hold- per set of five. -PC Pro system available for the cur- necessary test signals and down screws. Company, P.O. Box 358, Al- rent 525 -line video system. video -system calibration Thumbytes and Thumbits len, TX 75002. For the highest possible ac- signals. For audio tests, provide flip -top ease for curacy, most of the audio there are digitally -gener- non -flip -top PC's. They are "TEST" VIDEODISC. test tones were computer ated audio tones and sweep sold in sets of five, and fit Reference Recording's "A generated by Dolby Labora- signals, specific test signals virtually any slide -top case. Video Standard," is a disc tories, and converted to for digital -to -analog con- Thumbles hold I/O cards for the set up and alignment analog for the first time at verters; a dynamic -range tightly in place, and make it of home -entertainment sys- tone -level check; frequen- tems. Containing com- cy information from 15 Hz to prehensive audio and video 21 kHz; and instructions on test signals and a wide vari- how to use the test tones. ety of audio and video dem- The videodisc also pro- onstration material, the vides demonstration fea- laser videodisc is intended tures concerning the trans- to help consumers optimize fer of film to video, analog their home -viewing experi- and digital video graphics, ence, and retrieve from vid- electronic video effects and eo programs exactly what animation, and reference the producers put in. pictures for skin -tone and CIRCLE 15 ON FREE CIRCLE 16 ON FREE The videodisc was pro- color fidelity. Audio demon - INFORMATION CARD INFORMATION CARD duced by Joe Kane, who continued on page 95

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www.americanradiohistory.com turned on and/or the HORIZ Post- SCANNING RECEIVER SPECTRUM ANALYZER TION is moved, which can be continued from page 24 continued from page 25 somewhat tricky if not done carefully. The user tunes a signal peak frequency mode. In that mode, waveform superposed on it, for onto the center of the graticule, whenever the scanner stops at a certain settings of the horizontal with the VAR SPAN knob set to the new station, the frequency and SPAN. That is because of the tech- CAL position. The user then rotates signal strength of the station are niques used to design the instru- the VAR SPAN knob counterclock- output to the computer. We found ment, not because of modulation. wise, watching that peak. It'll ex- this novel way of searching for new Thus, VAR SPAN doesn't really pand in width, but should, ideally, scanner frequencies to be quite produce a 0 Hz span, since that remain centered, and not deflect efficient. would be a pure monochromatic to either side. The AR -2515 comes equipped tone. The TV waveform containing If it does deflect, then as the VAR with a telescopic antenna, DC the sync pulses is really a time - SPAN is rotated, the user alternates power cord, AC adapter, and an dependent voltage, whereas the between the VAR SPAN and HORIZ owner's manual that, while ade- video spectral peak is a true fre- POSITION knobs, to recenter the quate, could be much more infor- quency -dependent amplitude now -expanding peak. The reason mative. ACE Communications of- (voltage or power). If you repeat for alternating between them is fers several accessories, including for the audio, you'll see the time - that as the peak expands, it's max- a wide -band amplifier and an ex- dependent audio waveform, and imum becomes more difficult to ternal BFO (Beat -Frequency Os- it'll change amplitude and fre- locate, since the display appears cillator) for making SSB (Single quency as the sound varies. How- to be flatter. Thus, rotating each SideBand) transmissions intelligi- ever, the presentation, while that knob in turn gives greater accuracy ble. of an oscilloscope, not a spectrum and control, and an opportunity to The suggested price of the analyzer, is untriggered and drifts maintain a visual reference on the AR -2515 scanning communications across the screen. maximum as the peak changes receiver is $695. While we certainly shape. cannot call that inexpensive, we Horizontal calibration Once completed, with the VAR do feel confident calling it a bar- The horizontal needs to be cali- VAR SPAN set to ZERO SPAN and the gain. R -E brated each time the instrument is continued on page 81

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CIRCLE 86 ON FREE INFORMATION CARD CIRCLE 58 ON FREE INFORMATION CARD

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IF YOU'RE LIKE MOST VIDEO -CAMERA owners, you've built up an inventory of hours and hours of home video VIDEO movies. If you like to show your movies to others, you've undoubtedly found that even your best friends won't sit through an hour-long video SCENE SWITCHER of your son's first birthday. The solution is to edit your tapes into groups of short scenes. The trick is to do it with Make your next transition a smooth oneo professional results. The problem that arises is how to WILLIAM SHEETS and RUDOLF F. GRAF make the transitions between scenes or sources as smoothly as possible, without visually or a esthetically disturbing transitions. Our Video chronization source to control the "amateur" look to a program, and Scene Switcher is the key to smooth sync phase of other sources. Some should be eliminated. transitions. video equipment has genlock inputs A common way to deal with the In order to switch between video but, most of the time, the availability problem is to fade to balek, or some channels with a minimum of distur- of two genlocked sources cannot be other level. During this interval, bance, several technical requirements relied on. switching takes place, and since the must be met: When the signal source to a video screen is black, no transient effects monitor, TV receiver, or VCR is sud- are noticed. After a predetermined Sources must be identical in polar- denly switched, the synchronizing time, the new video is switched in and ity and type (for example, both NTSC circuits of the video device experi- then the fade from black to program is with negative sync) ence a discontinuity of input, in fre- performed. quency, phase, or both, depending on There are other methods that can be Sources must have the same levels. That requirement can be met using gain adjustments.

Color-burst phase must match in order to reduce color shifts between scenes.

Terminations and impedance matching must be considered in order to reduce reflections and "ghosting."

The time phases of the sources must be constant and have a fixed relationship. The sync pulses must co- incide both in time of occurrence and frequency, both vertical and horizontal. Most of the time there is no prob- the moment of switch- lem in meeting the first four require- ing in most instances. If, by chance, ments, as they are under direct control the vertical and horizontal sync pulses used. A black - of the system operator. However, the of both sources are coincident in time over can be "keyed" in the picture; last requirement, that the video (in phase) at the moment of switch- for example, a black over can be sources have sync pulses in phase, ing, there will be no noticeable distur- wiped across the picture, much like a does present a problem. That's be- bance. If, however, they are not (the curtain, either horizontally or ver- cause, when using two separate usual case), a momentary loss of syn- tically, or both (diagonal'.y). A black - VCR's, a VCR and a camera, or a chronization will occur. Depending over can also be broken up like a VCR and an over-the -air source, there on the characteristics of the sync sys- series of vertical or horizontal strips is generally no relationship between tem in the video device in use. a mo- that gradually enlarge, covering the sync phases. mentary flicker, jump, tear, or roll will picture with the effect of a Venetian The term "genlock" is used to de- occur in the picture-fit's objectiona- blind. By doing that vertically and scribe the act of using a master syn- ble, esthetically unpleasant, gives an horizontally at the same time, black

www.americanradiohistory.com FIG. 1-WARIOUS FADES, WIPES, AND EFFECTS can be keyed into the picture. You dcn't have to stick to simple horizontal or vertical fades, as complex fades are also possible; see how Danny disappears in a, b, and c. A diagonal wipe from regular video to effects video is shown in d, expanding vertical bars 'consume" the picture in e, expanding diamond -like patterns in f, and g, h, and i show three additional wipe patterns. dots appear in the picture that expand some form of synchronizing storage two are identical. Each channel has in size to first overlap and then com- system. However, that shouldn't be two switch -selected inputs. main or pletely obscure the picture. Figure 1 considered a serious limitation, since auxiliary, and each channel is fed to a shows those patterns. many fade -to -black techniques have á splitter circuit that separates the video The act of "keying" is actually vid- pleasing effect, and they provide a and sync components. That way, the eo switching using waveforms that are more defined differentiation between video can be processed separately tied to the sync pulses or other picture scenes. from the sync. The sync is not pro- elements, such as the luminance level cessed in any way. (luminance keying) or chroma level Basic operation The video from CHI first passes (chrominance keying). By producing The Scene Switcher basically con- through an analog switch (NORMAL/ such waveforms, a great variety of sists of two parts, as shown in the EFFECTS) that either passes it or selects switching and special effects can be block diagram in Fig. 2. A video CHI video that has been altered by an produced. Note that the effects are switching system is used to switch in external special -effects unit (for ex- performed steadily on the video, and various video effects, fade levels, and ample, the Video Palette described in that the sync pulses must remain un- to select channel I (CHI) or channel 2 the September and October 1987 is- altered during the switching process. (CH2), and a waveform generator is sues of Radio -Electronics). Since For wipes, keying, or other switch- used to generate keying waveforms to the video from the special -effects unit ing between two sources without an drive the analog switches at precisely is inherently synchronous with the intermediate fade, the two sources timed intervals. CHI video, direct switching is possi- must be genlocked or synchronous. There are two video channels (CHI ble, and you can wipe the altered There is no easy way around that, save and CH2), but we will describe the scene over the original one. for a large video buffer memory. or operation of only CHI, because the Next, the video is fed to another

www.americanradiohistory.com II be

analog switch, the FADESEI.LcroR. The sionnling amplifier, and mixed with vertical, or both sweeps, varying the output of that switch is either un- appropriate sync. The system output trip level causes the comparator to altered video or a DC background is composite video. switch at varying points in either the level from the fade level generator, The keying generator consists of a horizontal or vertical scan. Therefore, which is variable between black set of sawtooth-wave generators. since the comparator output is the the (about zero volts) and white (1 to 1.5 Sync from CHI or CH2 is fed to a keying waveform, we can control volts). That is determined by the set- phase -locked loop, where constant position of the switching at any desir- ting of the FADE LEVEL control, which outputs of 15.74 kHz and 60 Hz are ed point in either the horizontal or gets its switch signals from the con- generated, phase locked to the video vertical scan cycle. trol panel and the keying generator. input waveform. Those outputs are The switching waveform is fed to During a line -scan internal, several fed to the horizontal and vertical the control panel and then to the cor- switching actions may take place, sawtooth generators. rect analog switches in the video causing various pattern configura- The generators each produce two channels. Several switching patterns tions to be generated on the monitor waveforms; a sawtooth at eight times can be generated, using the x 1 or x 8 screen. the input frequency and a sawtooth at vertical, the x I or X 8 horizontal, or Next, the video goes to a switch the input frequency. The sawtooth various combinations. network that routes it to either side of waveforms are fed to a comparator, The circuit features external access the FADER control, or selects CHI or whose "trip" level is adjustable. The capability to the switch signals and CH2. Both analog switches are driven sawtooth is compared to the trip level sync outputs via emitter followers. by the keying waveform from the key- from the keying control, which may That permits using an external coming generator and control panel; be manual, or automatic. puter or microprocessor to generate switching may take place several When the sawtooth exceeds the trip other switching patterns than we have times during a line scan, depending level, the comparator switches. Since here, if desired. That is left as a proj- on the effects desired. The output the sawtooth level varies syn- ect for the experimenter or computer from the FADER control is led to a chronously with the horizontal, or hobbyist.

CH1 EFFECTS INPUT

CH1 COMPOSITE STRIPPED VIDEO OUTPUT VIDEO VIDEO = SPLITTER J9 CH1 VIDEO CIRCUIT FADE SELECTOR SYNC INPUT CH1 NORMAL/EFFECTS UMMING AMP AND CHI SYNC 2 BUFFER VIDEO SPLITTER CH2 VIDEO CIRCUIT SYNC 0 TO ANALOG INPUT CH2 SWITCHES

CH2 SYNC FADE LEVEL FADE t ttt tt CH2 GENERATOR LEVEL STRIPPED CONTROL VIDEO PANEL

CH2 EFFECTS INPUT KEYING SYNC TO OUTPUT AMP SYNC WAVEFORM SWITCH & LOGIC 8H HORIZONTAL SAWTOOTH GENERATOR COMBINER & FADER VERT. & 15.74k COMPARATOR - HORIZ. SYNC PLL

V VERTICAL MODE SELECTOR 60Hz SAWTOOTH 8V GENERATOR 1V *eth s AUTOMATIC MANUAL KEYING KEYING KEYING - GENERATOR SPEED RAMP FADE/KEY GENERATOR CUE

FIG. 2-THE SCENE SWITCHER BASICALLY CONSISTS OF TWO PARTS, as shown in this block diagram. A video switching system is used to switch in various video effects, fade levels, and to select channel 1 (CH1) or channel 2 (CH2). A waveform generator is used to generate keying waveforms to drive the analog switches at precisely timed intervals.

35 www.americanradiohistory.com Circuitry zontal-delay multivibrator, in which function on the vertical sync pulses Due to the large amount of circuit- R5, R6 and C6 determine the period. from pin 3 of ICI; IC3-a is the delay ry, very detailed descriptions of every The multivibrator produces an 8 - and IC3-b generates a 16 -microse- circuit will not be given. Only a single microsecond pulse triggered by the cond pulse which is active during in- example of each essential block will leading edge of the sync pulse. The 8 - dividual fields of the TV signal. Dur- be described in detail, since much of microsecond pulse is used to initiate ing vertical -retrace intervals, it is the circuitry is repetitive. another pulse generated by IC2-b, desirable not to gate on the composite Referring to Fig. 3, video is fed which is active only during the line - video, so horizontal multivibrator through Cl and filter R1 -C2 (to re- scan portion (the video) of the video IC2-b is locked out during the ver- move excess noise) to sync -separator waveform. The IC2-b pulse is used to tical -blanking interval, when pin 10 is IC1, an LM1881N; it separates the gate the video -only component from low. horizontal and vertical sync from the the composite video waveform (R7, Figure 4 shows the sync selector video. Composite horizontal sync R8, and C7 set the width of the pulse and PLL block. When SYNC SELECT

(negative -going pulses) appears at pin at 53 microseconds). (pin 2) of IC4 is high SYNC I selected, 1, and is then fed to IC2-a, the hori- IC3-a and IC3-b perform a similar and when it's low SYNC 2 is selected.

1M 5V R3 R7 10f2 33K BURST GATE OUT R8 R5 136 o R2 S C3 C5 25K R13 331( 25K 100 } 10µF 01 33K - C6 330pF C7 0022 5 8 4 4 8 16 3 14 Cl 15 11

2 IC1 IC2-a 12 IC2-b HORIZ LM1881N Y, CD4528 ir CD4528 BLANKING pF, 13 ur r68002I C10 R9 - R11 212 C4 4.7K iviver .01 4.7K R4 25EK VIDEO 01 680K T INPUT R10 Co - I C9 CHI OR CH2 25K T.11 2.2µF 5 3 16 14 15 11

IC3 d I C3 -b VERT CD4528 %, CD4528 BLANKING 10

FIG. 3-SHOWN HERE IS A SYNC SPLITTER. Video is fed to pin 1 of sync -separator ICI. Composite horizontal sync appears at pin 1. and composite vertical sync appears at pin 3.

S10) (FROM 5V SYNC SELECT R16 2.2K (SYNC 3.9K C10I .L C15 (FROM IC2 PIN9) .047 R26 R27 TO VIDEO .01 33062 Z SYNC 1 MIXER BOARD) 110 33011

12 V. FREQ. 60Hz O (TO R55) 13 O H. FREQ. 15.74Hz IC5 (TO C26) 2 LM1880 11 PLL R18 R24 R19 2:c16.047 15K (TO PIN 9 IC17 C14 3.3K: 100K 3 AND IC19) C13 C 1µF -h- 'M +12 SYNC SELECT 01 \1 4 + R25 C17 C18 10052 Wti .01 10µF R21 SYNC 2 C21 C20 T Lt R20 2.2K (FROM IC15 PIN 9) C22 T 120pF l 47012 3-40pF 22p ¡ç 2 2mH HORIZONTAL VM WS- LOCK C24 C19 R23 R22 ADJUST .001 .1 T 2.2K 47Oí2

FIG. 4-SYNC SELECTOR AND PLL BLOCK. When pin 2 (SYNC SELECT) of IC4 is high, SYNC 1 selected, and when it's low SYNC 2 is selected.

36 www.americanradiohistory.com PARTS LIST

All resistors are 1/4 -watt, 10%, un- CLO, C101, C208-0.1 µF, Mylar IC13, 1021, IC22-LM318N op -amp less otherwise indicated C2, C12, C202-470 pF, ceramic IC17-1C20-CD4053B analog multi- R1, R201-680 ohms disc plexer demultiplexer R2, R3, R29, R62-R64, R134, R135, C3, 318, C27, C30, C35, C36, C37, 10301-LM7812 12 -volt regulator R127, R128, R140, R141, C:,8, 041, C47, C50, C203, C307, IC302-LM7805 5 -volt regulator R143 -R150, R202, R203-10 0309, 0311-10 µF, 16 volts, elec- IC303-LM7905 -5 -volt regulator ohms trc lytic D1, D100-1N914B diode R4, R204-680,000 ohms C4, C5, C13, 015, C17, C32, D301 -D303 -1N4007 rectifier diode R5, R7, R205, R207-33,000 ohms 043-045, C48, C49, 0101, C102, Q1-03, Q5, Q6, 0101, 0103a -f, R6, R8, R10, R12, R42, R45, R47, C-05, C106, C109-0116, C204, Q105 -2N3904 NPN transistor R49, R206, R208, R210, R212- C205, C302, C303, C305, C306, 04, Q102, 0104a -f-2N3906 PNP 25,000 ohms, potentiometer C308, C310-0.01 µF, ceramic transistor R9, R11, R32, R33, R36-R40, R52, disc Other components R53, R58, R59, R130, R209- C6, 0206-330 pF, NPO L1-2.2 mH coil 4700 ohms C7, C207-0.0022 µF, Mylar T1-120VAC 24VAC, 500 mA trans- R15, R17, R21, R23, R28, R30, R31, C9, C209-2.2 µF, tantalum former R34, R41, R54 -R56, R61, R100, 010 C16, C26, 028-0.047 µF, My- J1 -J10 -RCA jack R101, R104, R105, R112, R114, la S1-S3-SPDT switch R118, R123, R124, R138a-R138f- 014 042-1 µF, 35 volts, electrolytic S4, S10, S11-SPST switch 2200 ohms 021-120 pF, ±5%, NPO S5-S9-SPDT with center off R16-3900 ohms 022-3-40 pF, trimmer Miscellaneous: project case, wire, R13, R18, R213-3300 ohms 023-22 pF, NPO line cord, solder, etc. R19, R102, R103, R106, R111, C24, C25, C29, 039-0.001 µF, My- R120 -R122, R136-100,000 ohms la - R20, R22-470 ohms 031 -470 pF, NPO R25-100 ohms C103-5 pF, NPO Note: A partial kit consisting of the R26, R27, R139a-R139f-330 ohms C104, C107-2-18 pF, trimmer two PC boards and only the R35, R57-5000 ohms, potentiome- C3C1-4700 µF, 25 volts, electrolytic parts that mount on them is ter C3C4-2200 µF, 25 volts, electrolytic available from North Country R43, R50, R51-1000 ohms Seniconductors Radio, PO Box 53, Wykagyl Sta- R44-1 megohm Cl.I IC14-LM1881N video sync sep- tion, New Rochelle, NY 10804, for R46, R48, R113, R116, R119, R126, arator $137.50. The kit does not contain R129, R131. R142-10,000 ohms IC2 IC3, IC15, IC16-CD4528B dual any of the parts that mount off R60-47,000 ohms rronostable multivibrator the board, such as the switches, R132-68 ohms IC4-7400N quad 2 -input NAND gate control potentiometers, RCA R108, R133-82 ohms IC5-LM1800N PLL FM stereo de- jacks, power supply compo- R115, R125-2000 ohms, potentiom- n- odulator nents, project case, etc. A set of eter IC6, IC9-LM565N PLL IC two PC boards is available sepa- R110, R117, R137-22,000 ohms IC7, 1010-74093 4 -bit binary coun- rately for $27.50. Add $2.50 to R24-15,000 ohms tE r either order for postage and Capacitors IC8, IC11, IC12-TLO81 wide -band- handling. New York residents Cl, C8, C11, C19, C20, C33. C34, width JFET-input op -amp must include sales tax.

Sync from pin 4 of IC4 is fed to a filter Fig. 5. There are four circuits-two VERTICAL PATTERN SELECT switch. network (R16, R17, CIO, C11, C12) for horizontal and two for vertical. The triangle waves needed to pro- and then to IC5, an LM1880 PLL. Horizontal square -wave pulses at the duce keying waveforms are obtained Components C13, C14, R18, and R19 junction of C25 and C26 are differen- from PLL circuits IC6, IC7, and IC8 help determine loop parameters; R20, tiated by C25 and R28. Therefore, Ql for horizontal, and IC9, ICIO. and R21, C22 -C24, and LI are for the is momentarily forward biased during ICII for vertical. Only the horizontal internal oscillator of IC5 operating at sync intervals, and C33 is thus dis- circuitry will be discussed, as the two 503 kHz; and C19, C20, R22, and charged through R29. When Q1 is cut are similar except for component Val- R23 are feedback components. off, C33 charges toward + 5 volts ues, and their operation is identical. R24 and C16 are vertical -timing through R30 until discharging again Horizontal sync is fed through C26 components necessary for correct op- at the next sync pulse. Q2 and R31 to an LM565 PLL, which is biased by eration of IC5, and R25, C17, and form an emitter follower to interface R32 and R33, and supply bypassed C18 are supply decoupling compo- the waveform, which is a sawtooth of by C27 and C30 for the ± 5V lines. nents. A signal at the horizontal fre- about 1-2 volts at the horizontal fre- C28 is a loop filter capacitor and C29 quency appears across R26. Capaci- quency, to HORIZONTAL PATTERN SELECT suppresses spurious responses. The tor C22 is adjusted for lockup with the switch, SI. VCO frequency at pin 8 is nominally

SYNC I or SYNC 2 input. The outputs Vertical sync pulses (very short and 126 kHz (480 Hz for the vertical cir- (pins 12 and 13) are fed to sawtooth negative -going) are directly inte- cuit). It is set by R34, R35, and C31. generator circuits for vertical and grated by R60 and C42, and DI pro- The VCO output at pin 4 of IC6 is fed horizontal frequencies, respectively. vides a discharge path. Emitter - to the pin -8 input of IC7, a 74C93 The keying circuits are shown in follower Q6 and R61 feed S2, the four -stage counter. Only three stages

www.americanradiohistory.com . +5V + R34 i-. C27 C29 2.2K 10µF C28 HORIZ. SYNC .047 .1.001 FROM IC5 TR35

10 6 1 7 PIN 13 C26 5K R63 .047 101! Znu' 2 IC6 9 - + 5V o-IE 3 LM565 4 C25 "" "Oh - 1 C31 er,.011 C44 R32 R33 470pF 001 1 5 4.7K 4.7K + + 5V + 5V C30 R28 = R62 i 10µF 2.2K 1013 IC8 TL081 6 + 5V - 5V 44444 = C50 C49 = = C45 4 HORIZ 8 x HORIZ 10µF .01 .01 +5V PATTERN FRED 8H SELECT R54 SAWTOOTHO R30 02 2.2K C S1 R50 R54 x 1H Q1 2.2K 2N3904 .01 -i- C43 - 1K KEYER Q5 4 12 2.2K R49 2N3904 = .01 7 2N3904 KEYING - 5V 25K SIGNAL IC7 IC13 6 R29 KEY R51 WAVEFORM 74C93 1M318N 1K 3 R52 TO 1012 8 MIX C33 R31 'WV 4.7K R53 CONTROL .1 2.2K 2 11 _L 4.7K SWITCHES C48 HORIZ. -5V -5V SAWTOOTH 01 5V GENERATOR 836 R39 FROM 4.7K 4.7K RAMP GENERATOR S4 o 04 RAMP 2N3906 1 + 5V RANGE AUTOMATIC R37 R40 C34 7 FADE/KEY 4.7K 4.7K 1 F-=- R45 25K 03 R42 IC12 AAA, 2N3904 25K TL081CP 841 1 SPEED R44 3 2.2K 4 + 5V 1MEG R43 R38 1 1K 5V R46 4.7K -5V 10K AUTO R56 0 + 5V MANUAL 2.2K R47 O S3 -4.1. FADE/KEY 25K MAN

R57 KEYING C38 848 AUTO/MAN C39 5K 10µF - C36 001 10K VERT R55 SYNC 10 + 5V 2.;F 5V + 839 l IC9 9 7 ,r 480Hz U 4--- R38 4.7K C35 - LM565 4 log 4.7K IC11 C40 TL081

.1 -5V 4 C41 J_ lOµF = vw- 5V 12 iE VERT R63 PATTERN IC10 1011 +5V-4 74C93 SELECT 8 X8V O

2 11 06 XiV v S2 R60 VERT SAWTOOTH 2N3904 60Hz 47K GEN 5V /V1. + or C42 R61 lµF 2 2K Dl 1M 5V 1N914B FIG. 5 -THERE ARE FOUR KEYING CIRCUITS; two for horizontal and two for vertical.

are used to get a divide -by -8. The out of the four available waveforms feeds Q5 via R52 and R53. The out- divide -by -8 output (IC7 pin 12) is fed (V, 8V, H, and 8H). The resultant pro- put Q5 is a square wave whose duty back to IC6 pin 5, the phase detector portion can be varied to achieve vari- cycle depends on the signals for S3 input. Therefore, under lock condi- ous key patterns. The resulting and R49. It is used to drive the keying tions, the VCO frequency at pin 9 will waveforms are fed to comparator IC13 switches in the video mixer circuit. be 126 kHz (8 x 15.74) and willbea via R50. We'll continue next month with triangle wave. IC8 is a buffer ampli- IC13 is biased to a threshold by a further descriptions of the keying cir- fier and delivers the triangle wave to DC voltage from S3 and voltage di- cuits. Then we'll move on to con- SI. vider R46-RR48, or by a slowly vary- struction details and present printed - Potentiometer R49 is a mixer con- ing DC voltage from pin 6 of IC12, as circuit patterns, troubleshooting in- trol that taps any combination of two selected by S3. The output of 1C13 formation, and more. R -E

38 www.americanradiohistory.com L -1.1--

Tweak your circuits to perfection using our RC decade box.

MICHAEL A. LASHANSKY

increasing power of 10, hence the switches S7-S12 decrease in order of IF YOU DESIGN YOUR OWN PROJECTS, term "decade box". So, S1-S6 cover magnitude by a factor of 10, as the you've probably waded through a sea 100 ohms (ten 10 -ohm resistors), 1K switch number increases; the total of resistors and capacitors, looking (ten 100 -ohm resistors), 10K, 100K, 1 range is 100 µF-10 pE An open termi- for one that makes a circuit work; if Megohms, and 10 Megohms; a total nal on each switch (position 0) pro- not, you're lucky. Many professionals of 11.1111 Megohms. vides a way to eliminate the capacitor use resistor or capacitor decade boxes Any value can be selected from 10 for that switch from the parallel com- instead. Suppose the problem is an ohms to 11.1111 Megohms, with a bination, so that a parallel combina- op -amp feedback resistor, but you're minimum step of 10 ohms. If you'd tion of up to six capacitors can be

not sure. You can substitute the de- like to have 1 -ohm steps, use 1 -ohm selected. cade box into the circuit. By setting resistors for SI, 10 -ohm resistors for Suppose that an LC tank oscillator different values, you can monitor per- S2, 100 -ohm resistors for S3, etc., up has a known resonant frequency with formance for the right value. Most to 100K resistors for S6, for a total of a 0.022 µF capacitor in place. Since

resistor versions cost about $100, and 1.11111 Megohms in 1 -ohm incre- the resonant frequency of an LC tank capacitive versions about $200. Ours ments. All resistors must be 1% toler- is: f = l/27r VLC, then f is inversely costs a fraction of that, and can either ance, and fuse Fl provides current proportional to the square root of both replace resistors or capacitors, or let protection. The worst case in terms of L and C. If you set S9 to 0.022 µF and you create a series or parallel RC net- power dissipation occurs with a single turn S 10 to 0.0015 µF, the total capac- work. 1/4 -watt 10 -ohm resistor, shown in Fig. itance is 0.0235 µF, which isn't a 2. If more than one resistor is used, sufficient difference to cause a change Resistor substitution power -handling capability increases in frequency. Turning S10 to 0.0022

Figure 1 shows the decade box by 250 mW times the number of se- µF gives a total capacitance of 0.0242 schematic. Note that rotary switches ries resistors, so five 1/4 -watt versions ;IF, which is sufficient to decreases SI-S6 are in series, with the pole of will handle 1.25 watts. the oscillator frequency. each connected to the first position of Thus, the upper capacitance value the next. As they're rotated over posi- Capacitor substitution the oscillator can tolerate and which tions 0-10, an additional resistor goes The capacitor section of the RC is within the resolution of the decade in series. At position 10, the total is decade box connects all selected ca- box to provide is 0.0235 µF, 5% the sum of all resistors connected, and pacitors in parallel, since capacitors above 0.022 µft To find the lower zero at position 0. Each switch is an in parallel add in value. The ranges of capacitance limit, set S9 to the 0.015

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www.americanradiohistory.com I,mA find them, make your own from polarized versions; Fig. 3 shows how. The diodes you use depend on the power you want the decade box to be able to handle; for small -signal, you should use something like a 1N4148; for 125 higher power, you should use a 1N4001. Electrolytics have poor toler-

100 ances, 50% variation being common, so be careful. Those used in the prototype were within 10%. 75 Filter networks In addition to variable resistance or 50 capacitance values, our decade box

R 10!1 can configure RC networks using

P 250mW

D1 Cl a E,V 2b 7.5 10 12.5 15 17.5 20 22 5 25 N )1,

FIG. VS VOLTAGE CURVE for 1/4 -watt resistor dissipating 250 mW. 2-CURRENT C2 D2

µF, and decrease S10 now, instead of guarantee that one terminal on the increasing it as before. Individual ca- decade box will always be positive FIG. 3-CREATE A NONPOLARIZED capacitor tolerances determine the ac- and the other always negative, you pacitor from two polarized types, using curacy of the capacitive section, just need to use them in order to prevent 1N4148 diodes for small -signal purposes, like for the resistive section. The pro- the possibility of damage. If you can't and 1N4001 rectifiers for higher power. totype capacitors were selected using a capacitance meter; use only 5-10% tolerance or better. If you can't find a specific value, combine two or three capacitors in parallel until you get close enough to the right value. You should stay away from ceramic disks. Many catalogs list ceramic disks at 10% tolerance, which isn't really bad, or even 20% or + 80%- - 20% of rated value. If you don't use a capacitance meter, you'll never be sure you're using the right values. The best are silver mica, poly- propelyne, metallized polyester, or military ceramic; all have 5% tolerance, and some 2% or better. FIG. 4-THE VARIOUS CONFIGURATIONS are set using S13: (a) resistor only and (b) Finding 2.2-100 µF nonpolarized capacitor only (both in position Ric); (c) series RC (position SER); (d) parallel RC (position electrolytics can be somewhat diffi- PAR); (e) Low -Pass filter (position LPF); and (f) High -Pass Filter (position HPF). The terminal cult. Since you may not be able to numbers listed are those of binding -posts BP1-BP6.

S13, as in shown Fig. 4. The listing of TABLE 1-DECABOX TERMINAL CONNECTIONS which terminals correspond to what function appears in Table 1. The dif- Configuration S13 Position IN/GND OUT/GND ferent filter functions are as follows: Resistance R/C IN: BP1 OUT: BP2 Position R/C (Fig. 4-a) is pure resistance or capacitance mode. The resis- Capacitance R/C IN: BP5 OUT: BP6 tance is between binding -posts BPI Series RC SER IN: BP1 OUT: BP6 and BP2, the capacitance between Parallel RC PAR IN: BP1 OUT: BP6 binding -posts 5 and 6. Low Pass Filter LPF IN: BP1 OUT: BP6 Position SER (Fig. 4-b) selects a se- (Integrator) GND: BP3 GND: BP4 ries RC network between BPI and BP6. High Pass Filter HPF IN: BP6 OUT: BP1 (Differentiator) GND: BP3 GND: BP4 Position PAR (Fig. 4-c) selects a parallel RC network between BPI and BP6.

41 www.americanradiohistory.com PARTS LIST

All resistors are 1/4 -watt, 1%. C17-0.22 µF 043-330 pF R1 -R10-10 ohm C18-0.15 µF C44-220 pF R11 -R20-100 ohm C19 0.1 µF 045-150 pF R21 -R30 1000 ohm C20 0.082 µF C46-100 pF R31 -R40-10,000 ohm C21-0.068 µF C47-82 pF R41 -R50-100,000 ohm C22-0.056 1iF C48-68 pF R51 -R60-1 megohms C23-0.047 µF C49-56 pF Capacitors, nonpolarized C24-0.039 µF 050-47 pF electrolytics, 10%. C25-0.033 µF C51-39 pF C1-100 µF C26 0.022 µF 052-33 pF C2-47 µF 027-0.015 µF C53-22 pF C3-33 µF 028-0.01 µF C54-15 pF C4-22 µF 029-0.0082 µF 055-10 pF 05-10 µF C30-0.0068 µF Other components: C6-6.8 µF 031-0.0056 µF S1-S12-SP12P rotary switch, Radio C7-4.7 µF 032-0.0047 µF Shack 275-1385 C8-3.3 µF 033-0.0039 µF S13-2P6P rotary switch, Radio C9-2.2 p.F 034-0.0033 µF Shack 275-1386 Capacitors; military ceramic, 5% 035-0.0022 µF BP1-BP6-nylon binding posts, Ra-

. 010-1 p.F C36 0.0015 µF dio Shack 274-662 011-0.82 µF 037-1000 pF F1-125 mA fuse C12-0.68 µF C38-820 pF Miscellaneous: Panel -mount fuse C13-0.56 µF C39-680 pF holder (Radio Shack 270-362), un - C14-0.47 µF 040-560 pF drilled case (GC Electronics C15-0.39 µF C41-470 pF B-00210BG-BR), knobs (Radio C16 0.33 µF 042-390 pF Shack 274-416), 20 -22 -gauge solid hookup wire. Notes: A complete kit of parts with all resistors, capacitors, switch- . -.11 l ' - es, binding posts, fuse holder, I hookup wire, case, and knobs is available from Tristat Elec- tronics, 66A Brockington Cres, Nepean, Ontario Canada, K2C 5L1. Please specify the range of resistors and the wattage rating 4" 11. desired, whether Y-, 1/2-, or 1 - watt versions. Kits are $110.00 with 1/4 -watt resistors, $120.00 with 1/2 -watt resistors, and ALL HOLES ".32- INCH $130.00 with 1 -watt resistors, with an additional $7.00 sor shipping/handling. US funds, please.

Position LPF (Fig. 4-d) selects an RC Low-Pass Filter (LPF) or integrator, with input between BP1 (signal) and BP3 (ground), and output between BP6 (signal) and BP4 (ground). Position HPF (Fig. 4-e) creates an RC High -Pass Filter (HPF) or dit ferentiator, with input between BP6 (signal) and BP3 (ground), and output between BPI (signal) and BP4 (ground).

-2 2 Construction

a Keep wiring and component leads FIG. 5 ' as short as possible. Long wires only -WHEN YOU DRILL THESE HOLES, make sure the drill bit dosen't wander or the hopes won't perfectly line up. continued on page 79

42 www.americanradiohistory.com L - --J5)

THERE IS NOTHING MORE FRUSTRATING periment from our grammar school ed for automobile use, with added than not knowing where you are go- days. circuitry that provides it with an out- ing. Consider ancient mariners, ner- Of course modern technology has put that can be fed directly into a vously navigating mysterious waters, overshadowed our first experience personal computer. That makes it unsure of what lay ahead in their. with the compass. The compass de- suitable for applications such as a travels. They soon learned to read the sign met a major milestone when the computer-controlled model airplane, heavens and were eventually assisted gyro -stabilized remote -indicating an automobile navigation assistant, or by the mysterious powers of the navi- compass was introduced during a video camera that intelligently films gational compass. Now consider the World War II. Suddenly, navigation your journey. modern mobile robot, unsure of was automated, freeing the pilot from where it is going, anxiously prodding routine maneuvering. But modern Magnetohydrodynamics with tactile sensors and acoustic rang- technology has further improved on The iron -nickel core of our planet ing equipment. It, too, is a little re- that massive electro -mechanical de- generates a weak magnetic field. The lieved by the information contained in vice, and now there are new, afford- phenomenon is due to a large moving its compass system. All of us have able alternatives for your next robotic and highly conductive liquid mass in probably experienced the utility of a project. Earth's core. The study of magne- delicately balanced magnetic needle, We introduce our Digi-Compass tohyd'odynamics (MHD) suggests carefully suspended on a cork floating project. Actually it's a Radio Shack that by applying an electrical current in water-a most typical compass ex- electronic flux -gate compass, intend- under those conditions, a magnetic

DIGI COMPASS m Is your house rotati -ig... what about your computer? JJ THOMAS E. BLACK

www.americanradiohistory.com field is produced (conversely, apply- "square" saturation curve. The coming a magnetic field will produce an bination of materials and winding di- electrical current). The magnetic field rection prevent the drive current that is what causes compasses to point is induced into the saturation -control North. winding from being picked up by the COSINE It should be noted that magnetic OUTPUT sense windings. External circuitry North is somewhat different than true also protects against that condition, North (due to what's called magnetic which would cause measurement er- declination), and it may even wander rors. Extra windings and circuitry can over time. It is also dependent on your be added to minimize magnetic in- CONTROL geographical location. You can deter- INPUT clination-bulky gyro mechanisms mine the difference between magnetic SINE contain a similar feature. North and true North by consulting a OUTPUT The two quadrature signals pick up US Geological Survey (USGS) to- magnetic pulses that are related to the FIG. 1-A TYPICAL FLUX -GATE magne- pographical map. True declination is tometer is constructed by wrapping con- sine and cosine of the surrounding computed as: trol, sine, and cosine windings on a magnetic fields. External circuitry (Map -indicated declination + (an- toroidial core. switches the control winding on and nual drift rate x (current date - off at a low frequency, and the result- mappublish date))) Unsaturated magnetic material will ing ratios of the integrated sine and There is also a magnetic inclina- pull in magnetic flux lines, whereas cosine output voltages provide the tion, which is the vertical component saturated material will not (it com- data necessary to interpret direction. of Earth's magnetic field. Compass pletely ignores magnetic fields). So, Inside the flux -gate compass, the accuracy can be severely affected by if you gate Earth's magnetic fields sine and cosine voltage outputs are its horizontal position, so it is impor- into and out of saturation, they will used to steer an air-core resolver (see tant to keep your compass as level as alternately be concentrated and ig- Fig. 2). The resolver consists of a possible. nored. If you place a sense winding pointer and magnet, both attached to a near your magnetic material, you can freely rotating axle. Surrounding the Flux -gate magnetometer measure the strength of Earth's fields magnet are two coils oriented at right There are a number of different entering or leaving the material. The angles with one another. The magnet methods used in modern solid-state magnitude of the signal is propor- will align itself with the vector sum of compasses, but one of the most prac- tional to the Earth's field strength the two magnetic fields generated by tical is the flux -gate magnetometer. along the axis that has been sensed. the coils, which is a direct product of Although the difficulties in building As shown in Fig. 1, a typical flux - the currents applied to them. There- such a device have eliminated by inte- gate magnetometer is constructed by fore, by varying both the polarity and grating an off-the -shelf flux -gate au- carefully wrapping control, sine, and magnitude of the coil voltages, the tomotive compass into the Digi- cosine windings on a toroidial core (a axle assembly can be made to rotate a Compass, we will discuss the theory donut -shaped core made of iron parti- full 360 degrees. behind the device. cles). The sine and cosine windings The compass was intended to be Many magnetic materials exhibit give us quadrature outputs, which are mounted in a environment with some linear magnetization up to a certain analog outputs that are separated by vibration (car, boat, etc.) to aid the flux level. At that point they saturate 90 degrees. The toroidial core must be movement, as it tends to stick. While and lose their magnetic properties. carefully chosen for the proper sitting on your workbench, the compass may have to be tapped occasionally while moving the sensor. 1 FRONT COMPASS PCB Fortunately, our digital interface ig- SIN SIG > TO SINE R9 Vcc nores the position of the electro -me- INTEGRATOR 5.1K 3 WIRE ADDED TO 8 R25 COMPASS PCB chanical movement, so it does not 1012 R21 suffer from that mechanical problem. 10K L1 -a R22 C9 AIR -CORE Digi-compass interface 10K 22µF - RESOLVER Because the Digi-Compass must have as universal a computer interface TO COSINE IC2-b C10 Lt -b INTEGRATOR JRC3415 22µF - AIR -CORE as possible, it is designed to be used RESOLVER with an IBM PC or compatible, and communication to the compass oc- WIR ADDED TO curs through the standard LPT1, Vcc COMPASS PCB REAR LPT2, or LPT3 printer ports. The COMPASS L software is provided as a learning VACS PCB Vcc+8VDC tool, and it would not be difficult to `ND A-GNDJ+4VDC adapt the Digi-Compass to any computer that has four available I/O lines. The two programs available for the FIG. 2-INSIDE THE FLUX -GATE COMPASS, the sine and cosine voltage outputs are used Digi-Compass provide both a graphic to steer an air -core resolver. display of compass direction as well

44 www.americanradiohistory.com 13 al 920 ve., 25 %2N2222 1K 921 H1h 12 97 15052 o 911 ,,GJ 910 Vac R19 24 1K 1K -L- 1K o 12 S yM.--1,-4N4- Vcc VN -L R17; o 10K' C2 IC2-d 14 o VDD MAX LIMIT 4 LM324 Vcc 3 ICI a 10µF o R14' IC6 R4 4066 Vcc 6 13 13 o 1K 22K' M CT2 E LM324 Vcc 1 1 o 2 5 1 o REF 3 3 8 o Vcc INP 93 Vcc o 6 1500 ICI c 6 1C3 DATA 916 o A 4066 TLC548 Vcc 10K o REF - CS D o GNP CLK D R8 Vcc R9 o 22K i 11( GAIN o R15 913 10K o 1K 4 COS/SIN 10 0-- -191r- 1318 16 10K Cl MIN 10µF o 9 LIMIT o R12 o 1K o 14

Vcc COS SIG VDD +5.0V +6.5V Ji SIN SIG R22 D2 0825 01 l C5 0 MICRONTA 27052 COMPASS 6:2V 1N4001 10µF + 12V C3 tOµF GND + 12V Fi 3AG 3/4.A,

FIG. 3-SCHEMATIC OF THE DIGITAL -COMPASS INTERFACE. Two signals taken from the compass (cos and SIN) are use to generate direction -related data, which is then fed into a computer. The LM324 op -amp's output can swing only to VDD -1.5 -volts DC, so as a simple text -only display of direc- The COS/SIN control line is used to as long as Vflt) remains at or below tional degrees (from 0 to 360). switch between the sine (Y) and the 6.8 volts, no trouble will arise. The The interface circuitry used to cosine (X) compass output voltages. LM324 output can also go as low as 0 monitor the compass's output is rather When the control line is high, the volts, a must for extending the dy- simple. All that is required is an Ana- cosine voltages are available to the namic range of the input. Be fore- log -to-Digital Converter (ADC) for ADC, and when it is low the sine warned; other op -amps will behave each compass output. To keep the voltages are available. differently, so be sure to observe that cost down, only one eight -bit ADC is With COS/SIN high (cosine mode), requirement. used, and it is multiplexed between the analog switch ICI -c is on and ICI - As mentioned before, the ADC is a the two outputs. The eight -bit resolu- a is off. Op -amp IC2-a is a used as an serial device. That means that the tion of the ADC is adequate for the inverter-a somewhat abstract use for data, which is in single -bit form, is chosen off-the -shelf compass, and it the device. The cosine voltage from presented to the host computer over a provides more than two degrees of the compass is attenuated by R8 and series of host -provided clock cycles. resolution. In order to use a standard RIO before being passed by ICI -a. It It is up to the host to repack the data IBM-compatible printer port with its is important to limit the compass volt- bits into byte form, a process that is limited I/O lines, a serial ADC that ages to less than 5 -volts DC, or lin- performed in software. There are con- needs only four I/O lines was used earity will suffer. When COS/SIN is low siderable hardware advantages to (twice as many would be required on a (sine mode), ICI -c is off and ICl-a is using that type of device, but such typical eight -bit ADC). on, and attenuation is provided by ADC's are not useful in high-speed As shown by the interface sche- R12 and R13. applications due to the overhead in matic in Fig. 3, the printer port is Gain control over the switched sig- handling their data output. connected to the Digi-Compass internal is provided by IC2-b before it is The ADC (IC3) requires two refer- face circuitry by four opto -couplers. passed to IC3 (the TLC548 ADC), ence voltages, a clock, and a select They provide some isolation between and it sets the minimum voltage ap- line. The two reference -voltage inputs the computer and the compass but, plied to IC3. However, IC3 could be set the analog input thresholds that most significantly, provide a high de- damaged if the analog input voltage result in minimum and maximum dig- gree of noise immunity on long cable exceeds Vcc + 0.3 volts DC, but by ital outputs (0 to 255 decimal). As we distances, which can typically exceed using 6.8 -volts DC to power the op - will see during calibration, R17 and 25 feet. amp we have avoided the condition. R18 are adjusted to set those limits. 45

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www.americanradiohistory.com le own once you take the compass apart. Once inside the compass, find the 12VDC 8 -pin DIP IC (IC2 in Fig. 2) on the WALL DB -25 ADAPTER MALE bezel -mounted circuit board marked CUT NOTCH IN HOOD CONNECTOR "JRC3415" FOR POWER WIRES r or "NJM3415" (R23 is r J I right next to it on the PC board). Pin 7 of that IC is the cos SIG output and pin PIN 18 - 1 is the sIN SIG output. Solder a labeled 10 -inch 26AWG wire to each pin, and YEL C6 trim as necessary. 470µF GRN Find the 3 -pin power connector at 6 -CONDUCTOR PHONE CORD BLU PIN 2 the rear of the horizontal PC board. z 6 -PIN ( PHONE WHT PIN 3 Solder a 22AWG wire for + 12 -volts JACK RED PIN 4 DC and one for ground directly to the

BLK pins-+ 12 is the middle pin and GRN PIN 15 +12 0 ground is the one toward the center of YEL

1 IT I the circuit board (ignore the outer un- BLU BLK DATA SEL O used pin). You can double check for WHT RED + 12 and ground, as well as continuity CLK O o DIGICOMPASS RS -232 COS/SIN INTERFACE MODULAR in the newly installed power wires by JACK ADAPTER temporarily plugging in the compass's factory cigarette -lighter plug and ver- FIG. 4-THE RS -232 MODULAR JACK ADAPTER is wired as shown here. The capacitor ifying proper voltages. Now you can will fit inside of the adapter. remove the cigarette -lighter plug and throw it in your junkbox. The host then scales the digital num- Construction Pass the four new wires out of the bers into meaningful units such as The Digi-Compass interface is suit- compass cabinet through one of the "volts," but that doesn't involve the able for perfboard construction using vents on the bottom. Re -assemble the Digi-Compass. point-to-point wiring techniques. The compass, being careful not to crush Conversion of the input voltage is prototype is mounted in a plastic en- any wires. Temporarily connect + 12 initiated when the ADC's active -low closure (metal could affect the flux - volts to the new power wires, and ver- cs line (chip select) goes low. The gate sensor), which is attached to the ADC then waits for two rising edges bottom of the compass and serves as a PARTS LIST and then one falling edge of the CLK base. If you mount the interface sepa- line before recognizing the cs rately from the compass, use shielded All resistors are 1/4 -watt, 5%, un- condition (the delay debounces the cs wiring and keep the cable as short as less otherwise specified. input). possible. R1-R3, R21-150 ohms The most -significant bit (D7) then If you intend to operate the inter- R4-R8, R10-R13, R20-1000 ohms appears on the ADC's DATA OUTPUT face board more than ten feet from R9, R14-22,000 ohms line. The next seven clock pulses shift your computer, you should mount IC5 R15, R19-10,000 ohms out the remaining bits, highest to and R20 at the computer end, perhaps R22-270 ohms, 1/2 watt, 10% lowest. The computer controls the inside of the DB -25's housing. That R16-R18-10,000 ohms, 15 -turn clock and select line through one of may not be necessary, depending on trimmer potentiometer Capacitors the LPT printer ports, as we men- the environment the cable will be in. C1-C3, C5 -10µF,16 volts, Tantalum tioned previously. Be sure to use sockets on the IC's C4 -100µF, 35 volts, electrolytic It is important to note that the data just in case you need to replace one C6 -470µF shifted out represents the voltage that later. The voltage regulator does not Semiconductors was latched during the previous con- need a heatsink, and a 6.8 -volt Zener IC1-CD4066 quad switch version. On the fourth falling edge of diode can be used instead of the 6.2 - IC2-LM324 quad op -amp the clock the ADC samples the input volt Zener (D2) and 1N4001 diode IC3-TLC548 serial ADC voltage, which is not available until (D1) combination shown. Just make IC4-LM7805 5-volt regulator the next acquisition. That is not a sure that you use a 12 -volt DC power IC5-1C8-MCT2E opto coupler Q1 -2N2222 NPN transistor problem if you continuously access supply that can deliver at least 750 the ADC, but in an input multiplexing D1 -1N4001 1 -amp, 50 -volt diode mA. (see text) mode such as that used in the Digi- Connecting the interface involves D2 -6.2 -volt, 1 -watt Zener diode (see Compass, you must always read the dismantling the compass. Inserting a text) ADC twice, throwing out the first coin or a masking -taped screwdriver Other components measurement. blade into the left and right sides of J1-DB25 modular -jack adapter In ideal applications, the TLC548 the bezel's groove and carefully twist- F1 -3/4 -amp fuse can provide conversions in less than ing will allow the bezel to pop off. Of Miscellaneous: Plastic cabinet (pro- 25 microseconds. However, in this course you have just violated the com- totype used 4 x 2'/,s x 1'/,s inches), project, acquisition is deliberately pass's warranty, so be sure that it 12 VDC lA power supply, Micronta much longer due to limited band- works correctly before you dismantle high -accuracy auto compass, wire, sockets, perfboard, etc. width of the opto -couplers. it. Remember that you are on your

www.americanradiohistory.com ify that both the sine and cosine outputs vary from about 1.5-7.5 volts as you move the sensor in different directions. Do not allow the two outputs to touch each other, power, or ground, and don't be concerned if your com- iass doesn't quite reach the men- ioned voltages; they may be within a olt or two. The DB -25 connector used for the Tototype is actually an RS -232 mod - lar jack adapter; its a male DB -25 onnector on one side, and a 6 -pin hone jack on the other. The DB -25 ide plugs into your computer, and a -pin phone cord plugs into the jack de; the other end of the phone cord wired to the interface circuitry. The green wire is used for + 12, the yellow wire is ground, and the other four are for COS/SIN, CLK, DATA, and SEL. The prototype's color coding is shown in F G. 6-THIS IS WHAT YOUR COMPUTER'S SCREEN will look like when operating the Fig. 4, but it doesn't matter as long as d'gital compass. you connect the proper points in the interface circuitry to the proper pins "LPT3" as the only argument to the the compass needle using geometry of the DB -25 connector. A pho- program. Be sure to input a port name based on the X and Y values. It shows tograph of the finished adapter is that is installed in your computer, or compass direction in the form of a shown in Fig. 5. Don't forget to install the program will not execute (appro- pivoting compass needle. The analog the 474F capacitor (C6) inside the priate error messages are echoed). mode is capable of displaying both adapter. Standard command -line syntax is: direction and magnitude of Earth's COMPASS LPTn, where "n" is the magnetic fields. While in the analog Software printer port desired (1, 2, or 3). mode, if you rotate the flux -gate sen- Software is supplied in both com- The data display in COMPASS.EXE sor off the horizontal plane you will piled and ASCII text source code provides current acquisition informa- see the compass needle length shrink forms, and it is available for free as an tion. The X and Y values indicate the and grow. The longer the needle archive file (coMPAss.ARc) on the RE- digitized cosine and sine values from length, the greater the magnetic field. BBS (516) 293-2283. The source the compass interface. The "angle" There is considerable loss in ac- code should provide sufficient exam- value is the number of degrees from curacy while in the analog mode due ples as to the methods used to access North in the clockwise direction. It is to the software method in plotting the and convert the Digi-Compass data. interesting to note that North is both 0 needle. The analog mode converts the Because of the graphics code in and 360 compass degrees, depending X and Y values to Cartesian coordi- COMPASS.C, you may find the simpler on your heading. nates based on fixed center. The ac- TEXTCOMP.0 source much easier to The "mode" value shows when curacy of the analog mode is only fair read. The two programs are meant to you are in the Digital, Analog or Both at best, but could be improved by get you started in developing your mode; it can be changed by pushing optimizing the code. The angle value own applications. the "D," "A," or "B" keys. The and the digital mode's compass nee- There is a graphics -based program digital mode is the default and it plots dle are displayed with accuracy that and one that relies strictly on text out- exceeds the compass's electro -me- put. As shown in Fig. 6, COMPASS.EXE chanical movement. You can display produces a likeness of a handheld both the digital and analog needles at compass. The program requires an the same time while in the Both EGA graphics adapter and monitor, mode. or a CGA adapter that can display the The number of data acquisition CGA high -resolution monochrome averages can be changed by pushing mode. the "" keys. When the average is at There are some clever features in- the minimum value of zero, the X, Y, cluded in COMPASS.EXE. On startup, und angle values will be somewhat the program will attempt to automat- unsteady. The values become in- ically choose the printer port by exer- creasingly more stable as you move to cising all of the BIOS configured LPT the maximum of thirty-one, but ac- ports. If a properly operating compass quisition time will be very slow. The is found, the respective printer port is default of four is fine for most of the selected. You can skip that feature by FIG. 5-HERE'S WHAT THE INSIDE of the applications. including "LPT1," "LPT2," or adapter looks like. continued on page 82

www.americanradiohistory.com L _I Zy7 air

BRIAN PHELPS* c PLEÎYERS When servicing CD players, you need a good understanding of CD operation and basic troubleshooting ability.

THE CONTEST BETWEEN COMPACT DISK (CCD) players and phonographs is headed in the same direction as cassettes and 8 -tracks. The quality, versatility, and simplicity of CD's make them ideal for audio. First introduced in 1983, CD growth has been comparable to that for VCR's, and all market indicators point to continued success. Lower prices and availability of disks has sparked a sales boom since 1985. With the large number in use, service shops need repair techniques. This article will examine CD basics, key stages to analyze, and test 'Ne instruments.

CD basics Discs are single -sided, store about 70 minutes of stereo audio, are played from the underside, and are read using laser pickups. Tracks begin near the disc center, and move out- ward as a program plays. The information is recorded as microscopic surface variations (pits and flats) rep- resenting Pulse Code Modulation (PCM) audio, sync, and ID information. Audio is sampled at 44.1 kHz. Each sample undergoes 16 -bit A/D conversion, giving a theoretical 98 dB dynamic range (most manufacturers claim 90-95 dB). A CD player's laser pickup is never in physical contact with the disc, giving extreme accuracy, and no deterio- ration or mechanical noise as with records. The CD player carries separate stereo channels, but interlaced on a single track changing at fixed time intervals. The CD keeps step with those changes, and maintains high in - *Brian Phelps is a technical writer for Sencore Electronics.

52 www.americanradiohistory.com TABLE 1-SENCORE RECOMMENDED CD TEST EQUIPMENT

Type Requirements Sencore Gear Tests Dual Trace Scope Bandwidth: DC -60 MHz SC61 Waveform Clocks, Counters, D/A Sensitivity: 50 mV Analyzer Converters, Audio, Power Supplies, Laser Diode, PLL's

Frequency Counter Range: 250 MHz FC71 Frequency Clocks, PLL's, Oscillators Sensitivity: 20 mV Counter SC61 Waveform Analyzer Audio Tester Frequency: 0-15 kHz. variable SG80 Stereo Generator For audio injection Amplitude: 0-3 V VA62A Video Analyzer

Digital Voltmeter Amplitude: 100 mV -1 kV DC DVM37, DVM65A Power Supplies, Sled Drive, Sensitivity: 1 mV Voltmeters Resistance, Signal Amplitude Accuracy: .5% AC Leakage Tester 500 uA capability PR578 "Powerite" To test for AC line leakage to Isolation Transformer metal case

Audio Tester Line level PA81 Stereo Analyzer To monitor quality and level of line outputs, and test audio stages

Variac Isolation type, 0-140 V AC, PA57 "Powerite" Power supply troubleshooting variable with line monitor Isolation Transformer and providing isolation

pits, high for flats) passes through the optics into infrared photodiodes. The D/A photodiode signal is what is then used S/H soNsem-F.eigeox,».. to reproduce the original audio.

1 RIGHT AUDIO Tracking \1 Two error -signal sub -beams are produced by routing the laser through PREAMPS a glass diffraction grating ahead of SIGNAL and behind the main beam. After re- PROCESSOR flection from the disc, each is routed through the to LASER optics photodetector POWER The signal from the two PICKUP diodes. error SUPPLY SYSTEM SERVOS sub -beams is converted into an elec- CONTROL MICROPROCESSOR trical signal and fed to an error-signal amplifier. If the disc tracking is pre- \I cise, the error-signal amplifier output FRONT is zero. The slightest radial tracking LASER MOTOR PANEL error causes the input differential be- CONTROL SERVO CONTROLS tween the right and left error signals to produce an output, fed to the radial - FIG.1-USE A UNIVERSAL BLOCK DIAGRAM whenever troubleshooting, whether you're tracking servo. That moves the object working on a CD player, VCR, or TV. lens in order to correct the main -beam position. terchannel isolation above 90 dB. The mounted at the end of a rotating arm optical pickup is focused on the disc that moves from the center of the disc Signal processing surface by an objective lens, which is to the edge. In the other, a motor - Figure I shows a typical CD -player part of the pickup assembly. driven slide or sled assembly is used. block diagram. The laser is applied to As a disc is played, the beam fol- The output from the low -power laser the disc optically, and reflected into lows the track by a servo -operated diode is focused on the disc surface by photodiode detectors to produce au- pickup motor. There are two basic the objective lens. Reflected light dio, tracking, and focus signals. The pickup types; in one, the optics are from the surface variations (low for continued on page 82 53

www.americanradiohistory.com INDUCED N -CHANNEL GATE METAL ELECTRODE SOURCE DRAIN INSULATION LIMY! SILICON DIOXIDE)

It looks like an IC, DRAIN it's made GATE CONTROL out of ON=1=Vo0 semiconductor, but it OFF=O=Vss works like a

SOURCE mechanical switch! b

FIG. 1-IN a, AN N -CHANNEL E-MOSFET RAY MARSTON is shown. The channel must be enhanced with N -type charge carriers to turn the transistor on. The symbol for the E- MOSFET (b) shows broken lines between OFF=O=Vss IN/OUT ON=1=Vos the source and drain, indicating that the 01 transistor is normally off. CONTROL (N)

IN/OUT CONTROL RoN OUT/IN 03 CMOS BILATERAL SWITCHES CAN BE RE- -- -o ON=1 30052 TO (P) garded as Single Pole Single Throw OFF=O 150052 (SPST) electronic switches. The b OUT/IN toughest thing about bilateral switch- =1G. 2-CMOS BILATERAL SWITCH (a) im - dates a mechanical on/off switch. When 02 es is learning how and when to use 05 closed, the bilateral switch (b) has a series (P) them. And that's exactly what we're (N) resistance of 300- to 1500 -ohms. V ss going to show you. Because, even though they function like mechanical Bilateral switches can be as simple switches, the differences between the as the 4016B and 4066B, which house two are many. four SPST switches, and as complex IN/OUTo- OUT/IN Conventional toggle switches have as the 4097B, which houses two sin- CONTROL obvious limitations when it comes to gle -pole eight -position switches L---0 ON=1 Oft high-speed switching. For example, (similar to an electronic SP8P rotary OFF=O b the metal contacts within a switch switch). FIG. 3-IMPROVED CMOS BILATERAL tend bounce a to for millisecond or switch (a) has a 90 -ohm series resistance two before making a solid electrical Enhancement MOSFET (b). connection, introducing glitches into Bilateral switches are integrated digital circuits and pops into audio using Complementary Metal -Oxide is called the drain. Here's how it circuits. But don't throw out your me- Semiconductor (CMOS) technology. works. chanical switches just yet. That's be- Figure l -a shows an enhancement E-MOSFET's are normally off de- cause, even with all their problems, MOSFET (E-MOSFET), which is the vices. Electrons can not travel from they're easy to use, readily available, type of transistor used in both CMOS the source to the drain because or- and cheap. digital IC's and bilateral switches. dinarily there's no conducting chan- On the other h id, a bilateral In the N -channel Enhancement nel between the wells. However, when switch can be turned on and off sev- Metal -Oxide Semiconductor a positive voltage is applied to the eral million times per second, they Field -Effect Transistor (E gate (with respect to the source), then can pass both an, and digital sig- MOSFET), the substrate is made of P- a negative electrostatic field is induc- nals in either dir. on, they can be type semiconductor with two N -type ed into the channel (P substrate). controlled by digital -logic [C's, and semiconductor wells; between the That's because the metal gate and they introduce no digital glitches or wells is the channel, and on top of the semiconductor act as a tiny capacitor CO audio pops. When turned on, the channel is a layer of glass (Si0z sil- with the silicon dioxide acting as a CMOS switch behaves almost like a icon dioxide) and a metal electrode; dielectric. The induced negative field short-circuit (about 90-300 ohms); that's where the term "metal -oxide increases the number of N -type mi- ó when turned off, it behaves almost semiconductor" comes from. The nority -charge carriers in the P-sub- E like an open circuit (near -infinite im- metal electrode is called the gate, one strate; essentially, turning a P -type pedance). well is called the source, and the other semiconductor into an N -type semi -

www.americanradiohistory.com rated, signal currents can flow in ei- O IN/OUT IN/OUT ther direction, provided that the signal voltages are within the Vss-to-VDD ON limits. The FET's source and drain CONTROL CONTROL as or out- OFF OFF can be used either an input put-thus the term bilateral (both di-

OV rections) switch. In practical circuits, Ql and Q2 exhibit a finite resistance FIG. 4-TO CONTROL A BILATERAL SWITCH, use a single -polarity supply for digital (RON) when saturated, and the equiv- signals (a), and a split -polarity supply for analog signals (b). alent circuit in Fig. 2-b shows an RON that varies from 300 to as much as two P -type semiconductor wells. 1500 ohms; that resistance depends

VOD IN/OUT When a negative voltage is applied to on the magnitude of the Vss-to-VDD the gate (with respect to the source), a voltage, and on the magnitude and positive channel is induced between polarity of the actual input signal. LOGIC . LEVEL the source and drain, so the transistor Figure 3-a shows an improved ver- CONTROL INPUT CONVERTER turns on. sion of the CMOS bilateral switch. (0V OR VDD) An additional two FET's (Q3 -Q4), OV_Vss When P-channel and N -channel E- OUT/IN VED MOSFET transistors are connected which also act as a bilateral switch, back-to-back, they are said to be are added in series with Q5, with QI's FIG. 5-SOME IC's FEATURE INTERNAL source tied to Q5's drain. When the logic -level converters, so an analog wired in inverse parallel or comple- switch is controllable via a single -ended mentary pairs; hence the name control input goes low, Ql's source input. CMOS. sees Vss, the Q3 -Q4 bilateral switch is off, and the Ql-Q2 bilateral switch is also off. When the control input goes high, Q5 turns off, both bilateral switches Q3 -Q4 and Ql-Q2 are en- SYNC SIGNAL AUD 0 SIGNAL 1 hanced (turned on) and, because they are in parallel, the RON resistance is AUDIO SIGNAL 1 AUDIO SIGNAL 2 reduced to about 90 ohms. That elimi- AUDIO SIGNAL 2 AUDIO SIGNAL 3 nates the variations in RON, as shown

AUDIO SIGNAL 3 SYNC SIGNAL in the equivalent circuit of Fig. 3-b. The only disadvantage of Fig. 3 is that it has a slightly lower leakage resis-

SYNCHRONIZED tance than Fig. 2. MULTIPLEX DRIVER E Switch bias Correctly biasing CMOS bilateral FIG. 6-A 4 -POSITION MULTIPLEXER FEEDS three audio signals through a single data switches requires that you know two line. At the other end, a demultiplexer re -assigns the audio back into separate lines.

Bilateral switches IN/OUTOyi 1 1fi; VDD Figure 2-a shows the inside of a r I 15 ' IN/OUT 2x 40 bilateral switch where an N -channel IN/OUT 2y 2 OR ,l\ 'r 14 VDD and P-channel MOSFET are wired in IN/OUT A I`1,~ 40668 I 14' IN/OUT 1x Y COMMON 3,' I A inverse parallel (drain -to-source and A 1,2 13; CONTROL A 13 X COMMON OUT/IN source -to -drain), and have their gates IN/OUT 3y 4 3 i ,L - 12) CONTROL D biased in anti -phase via a pair of in- OUT/IN B'3,-2) IN/OUT 1y'\ 5, 9-`i12) IN/OUT Ox B I verters. When the control signal is at I 'r O --x 11 IN/OUT D IN/OUT B I 4 `' 11I IN/OUT 3x I logic -level 0, the gate of Q2 is driven INH 6,' to VDD and the gate of Q1 is driven to I CONTROL B' 5 10; OUT/IN D VEE 17 I 10 A r Vss; under those conditions both I` r 9 I I CONTROL C I 6 OUT/IN C MOSFET's are cut off, and an open Vsg'\ 8 ' i 9 B I ,r, t circuit exists because the FET chan- r 'T' VssI\7 i 8 I IN/OUT C T r' nels are not enhanced. When, on the other hand, the control signal is at FIG. 7-THE 4016B AND 4066B each have INPUT STATES logic level 1, the gate Q2 is ON CHANNEL four independent "SPST" switches. of driven INH B A X Y to Vss and the gate of Q1 is driven to ó o 12 conductor. Now electrons flow from VDD; under those conditions both 2 3 3 the source to the drain through the MOSFET's are driven into saturation, NONE induced channel. and a near short-circuit exists because X - DON T CARE the FET are by the D In P -channel Enhancement channels enhanced FIG. 8-THE 4052B HAS TWO SP4T bilat- MOSFET's, the substrate is made of gate's electrostatic field. eral rotary switches (a); its truth table is N -type semiconductor material with Note that when Q1 and Q2 are satu- shown in b.

www.americanradiohistory.com things: The voltage polarity of the control logic, and the voltage polarity vo, of the signal to be switched. For example, if the signal is analog, does it swing above and below ground, and if it's a digital signal, does it just go between ground and Vcc? Figure 4 vss shows two ways of biasing the bilateral switch. a b To turn on (close) a bilateral FIG. 9-UNUSED SECTIONS OF THE 4066B must be disabled using any one of connec- switch, you must connect the control tions a through c. terminal to VDD. To turn off (open) the same switch, connect the control IC1-a IC1-a IC1-b terminal to Vss. For switching digital B signals, use them with a single -ended A o supply. Also, must be a positive C -A VDD ON - CONTROL voltage that's equal to or greater than o- C -B the digital signal voltage, with a max- OFF imum of + 18 volts. For switching Ao oB SPDT SWITCH analog signals, a split power supply O o\- SPST SWITCH must be used, so that the signal is held A 9 Co a at half the supply voltage, which al- b lows the signal to swing above and below ground. The positive supply IC1-b IC1-a IC1-b rail goes to VDD, and the negative rail A o o b goes to Vss; both rails must be greater C -A than the peak value of the input sig- F -D nal. Generally, the supply values used C -B CONTROL F -E for bilateral switches are limited to ON_ ± 9 volts. D Note that if a split power supply is OFF - IC1-c F IC1-d used, the control logic must swing to Ao oB Aq Bq OD 9E the positive rail to turn the bilateral DPST SWITCH DPDT SWITCH Co oD switch on, and to the negative rail to o c turn the switch off. That arrangement d is inconvenient in many practical ap- FIG. 10-IMPLEMENTATION OF THE FOUR BASIC SWITCHING FUNCTIONS (a through d) plications so, as shown in Fig. 5, using the 4066B. some IC's (notably the 4051B to 4053B) have built-in logic -level converters. o They allow a digital signal to 1 be used as the on/off controlling log- A L ic, while still using a split supply in the circuit to correctly bias analog signals. Ì 22.5.0

Time L sharing ON - Bilateral switches are often used in B OFF CONTROL multiplexer and demultiplexer cir- a b cuits. Figure 6 shows the difference FIG. 11-BY PARALLELING FOUR SPST SWITCHES, the RON resistance can be reduced to between the two types. A multiplexer only 22.5 ohms. allows information from a number of separate data lines to be sequentially Best-known IC's Another well-known IC is the applied to a single data line. On the The best-known CMOS bilateral 4052B, which is a multiplexer/de- other hand, a demultiplexer allows in- switches are the quad 4016B and multiplexer featuring built-in logic - formation from a single data line to be 4066B. Both have four independently level converters, and three power -sup- distributed to any number of separate accessible SPST bilateral switches, as ply pins (VDD, Vss, and VEE). Figure data lines. For example, three sepa- shown in Fig. 7. The 4016B uses the 8 shows that IC. It's a dual 4 -channel rate audio signals can be multiplexed simple form of chip architecture multiplexer/demultiplexer, and can be down a single cable, and then de - shown in Fig. 2, and is recommended thought of as a ganged, double -pole, multiplexed back into the three origi- where low leakage impedance is most four-throw (DP4T) rotary switch. In nal audio signals at the other end. The important. The 4066B uses the im- practice, the VDD is always taken to benefit is obvious, in that only one proved chip architecture of Fig. 3, and the positive rail, and Vss is always data line is needed to carry numerous is recommended where a low RON grounded. signals. resistance is most important. All digital control signals for chan - 56

www.americanradiohistory.com 4016B/40666 IC's flows to ground via R3 -LEDI, and the A few simple precautions should be control pin is tied to the top of R3 via taken when using the 4016B and R2. Thus when SI is briefly touched, the pin is pulled to the positive S1 4066B bilateral switches. Here they control IONI are: rail and the bilateral switch closes. TOUCH The R3 is at supply -line poten- PADS 1. Input and control signals must top of S2 never go above VDD or below Vss. tial and, because the control pin is tied (OFF) 2. Each unused switch must be dis- to R3 via R2, the bilateral switch is abled using one of the techniques latched closed. The switch can only shown in Fig. 9. be opened again by briefly touching 3. Figure 10 shows how to hook up S2, at which point R3 voltage falls to a 4066B (or 4016B) to implement ei- zero. Note that LEDI merely indi- ther SPST, SPDT, DPST, or DPDT cates the switch's state, and R1 pre- functions vents supply line shorts if SI and S2 FIG. 12-HERE'S A LATCHING touch switches. Those switching switch. Can you figure out how it works? can be expanded or combined. are both touched at the same time. Digital control Bilateral switches are used to digitally -control electronic components. CONTROL D D R O A B C 0 0 150K R5 3 0 0 0 0 1 140K 100K 0 0 1 0 130K

3 0 1 1 120K C CONTROL 0 1 0 0 110K

0 1 0 1 100K R6 0 1 1 0 90K OUT 100K 0 1 1 1 80K Cl 1 0 0 0 70K CONTROL B 1 0 0 1 60K 1 1 50K O 0 0 a l j 1 0 1 1 40K R7 1 1 0 0 30K 100K 1 1 0 1 20K

1 1 0 10K R4 17 - CONTROL A 1 1 1 0K 80K 0 -OPEN 1= CLOSED OUT R8

100K i IC1 40668 j

FIG. 13-DIGITAL CONTROL OF RESISTANCE made possible using bilateral switches.

FIG. 15-ALTERNATE WAYS to make a digitally -controlled 1st -order low-pass filter. C3

.004µF A B C D C .008µFy C4 o o o o 0 D 0 0 1 1nF

0 0 1 0 2nF C 0 0 1 1 3nF FIG.13 CONTROL CONTROL CONTROL CONTROL D B A 0 1 0 0 4nF RF O O 0 1 0 1 5nF

o 1 1 0 6nF

0 1 1 1 7nF Cl -d IC1 -c IC1 -b ICI -a o- met- 1 0 0 0 8nF

O O _ 1 0 0 1 9nF IN O 15& 47K 1 0 1 0 10nF

1 0 1 1 11nF 1 1 0 0 12nF --- 1 1 0 1 13nF

1 1 1 0 14nF R4 a Rt R2 R3 ' 1 1OnF 100K 100K 100K 100K 0 OPEN 1 -CLOSED IC1 40668

FIG. 14-DIGITAL CONTROL OF CAPACITANCE made possible using bilateral switches. nel -select, inhibit, and other similar 4. Each 4066B bilateral switch has functions, use those two rails as their a typical 90 -ohm RON resistance. Fig- logic reference. In digital applica- ure 11 shows how four standard switch tions, VE is grounded (tied to Vss). elements can be wired in parallel to In analog applications, VE must be make a single switch having only a taken to a negative supply rail, usu- 22.5 -ohm RON resistance. ally the negative value of VI)D, and must be limited to 18 -volts peak -to - Touch switch FIG. 16-OP-AMP GAIN CAN BE DIGI- peak. Generally, though, a lower volt- Figure 12 shows a self-latching TALLY CONTROLLED via the feedback re- age is used. touch switch. The switch current sistor (a), or input -resistor stage (b).

www.americanradiohistory.com Put Professional Knowledge and a shows how to vary the gain from unity

COLLEGE DEGREE R1 to x16 in sixteen steps, giving a gain in your Technical R2 Career through 2.7K 10K sequence of 1, 2, 3, 4,...16. Because the 3140 op -amp uses a split power supply, the 4066B must switch be- FIG.13 tween the negative and positive sup- R3 ply rails. The frequency of a 555 astable oscillator can be varied; that is done by connecting Fig. 13 as shown in Fig. 17.

FIG. 17 -555 -TIMER FREQUENCY can be Multi -gang potentiometers digitally controlled. Figure 18 is an interesting circuit to

Add prestige and earning power to -t+ 12V IC2 IS 40888 R2 your technical career by earning A B C D 10K íy¡. C1 Ra your Associate or Bachelor degree Rb Rd R1 9.1K 9.1K 9.1K through directed home study. 100K M/S -RATIO ' 02 Grantham College of Engineering R3 184148 awards accredited degrees in 10K D1 electronics and computers. IN4148 VARIABLE M/S -RATIO C2 OUTPUT An important part of being pre- 180pF pared to move up is holding the ALL POTENTIOMETERS FROM 10K TO 100K VIA R1 right college degree, and the absolutely necessary part is knowing FIG. 18-YOU CAN VARY A MULTI -GANGED POTENTIOMETER from 10K to 100K by your field. Grantham can help you varying an astable's mark/space ratio. both ways-to learn more and to earn your degree in the process. That means that they can vary, in dis- analyze. It shows a synthesized 4 - crete steps, the effective value of re- gang 10K -to -100K potentiometer that Grantham offers two degree pro- sistance, capacitance, impedance, is useful at frequencies up to 15 kHz. grams-one with major emphasis amplifier gain, oscillator frequency- The 555 timer outputs a pulse train in electronics, the other with major you name it. with a definite mark -space ratio (M/S Figure 13 shows how four switches ratio). As the pulse width decreases, emphasis in computers. Associate can make a digitally controlled re- the CMOS switch allows less of the and bachelor degrees are awarded sistor, which varies in sixteen steps of low-voltage AC to pass through; thus in each program, and both pro- 10 kilohms each. As long as the four simulating a high resistance. As the grams are available completely resistors are kept in the ratio pulse width increases, more low-volt- by correspondence. 1:2:4:8...etc, the number of steps can age AC goes through the switch per be increased by adding more resistor/ unit time, so the simulated resistance No commuting to class. Study at switch stages. Thus, a six -stage cir- is low. The 555 timer is used to gener- your own pace, while continuing cuit having resistors in the ratio ate a 50 -kHz rectangular waveform on your present job. Learn from 1:2:4:8:16:32 will give resistance vari- that has its M/S ratio variable from easy -to -understand lessons, with ation in 64 steps. Figure 14 shows how 11:1 to 1:11 via R1, which is used to help from your Grantham instruc- four switches can make a digitally control the 4066B. tors when you need it. controlled capacitor, which varies in If the timer's 50 -kHz switching rate sixteen steps of 0.001µF each. Again, is fast relative to the 15 -kHz signal Write for our free catalog (see ad- the circuit can be expanded by adding frequency, the average or effective dress below) or telephone us at more stages. The bilateral switches value of each gang resistance can be (213) 493-4421 (no collect calls) can be controlled manually, automat- varied by the M/S -ratio potentiometer and ask for our "degree catalog." ically by logic networks, by digital R1. Thus, if IC2-a is closed for 90% counters, or even by a micro- and open for 10% of each cycle (M:S Accredited by processor. Figure 15 shows how to ratio equals 9:1), the apparent (aver- the Accrediting Commission of the form digitally controlled filter net- age) value of the RA resistance will be National Home Study Council works. 10% greater, or equal to 10 kilohms. If Op -amp gain can be controlled dig- the duty cycle is reduced to 50%, the itally by connecting Fig. 13 into the apparent RA value will double to 18.2 GRANTHAM feedback or input path. Thus, in Fig. kilohms. If the duty cycle is further College of Engineering 16-a, the gain is varied from zero to decreased, so that IC2-a is closed for unity in sixteen steps of 1/15th each, only 10% of each cycle, the apparent 10570 Humbolt Street giving a sequence of 0/15, V15, 2Á5... up value of RA will increase by a decade Los Alamitos, CA 90720 to 15/15 which is unity. Figure 16-b to 91 kilohms. R -E

www.americanradiohistory.com J 7A-\_ D

Understanding relays, part I: Electromechanical versions

HARRY L. TRIETLEY

A RELAY IS AN ELECTROMAGNETIC Basic switching arrangements break -before -make in the first case switch, normally using the magnetic Relay contacts are available in dif- and make -before -break in the second. field from a coil to open or close one ferent switch configurations. The The versions are referred to as Forms or more sets of contacts. Like re- configuration of a switch is denoted A-D, a relatively standard notation. sistors and capacitors, they're often by the numbers of Poles ("P") and The number of poles is added in front taken for granted-until you need Throws ("T"). These can be indicated of the form letter, so the relays shown one! Then, you suddenly find yourself either by a number, or by the letters are IA, IB, IC, 2C, and ID. Relays

faced with a bewildering array of "S" (for Single ) or "D" (for Double). can use multiple contact types, like sizes, cases, contacts, power ratings, Some different configurations are lAIB, 2A2C, etc. Other variations and features. No one version is cor- thus SPST, SPDT, DPDT, or multi - exist, but are all based upon those. rect for all applications, and the pole (3PST, 4PDT) versions. A re- Form C momentarily opens both wrong one can cause poor perfor- lay's coil can either drive a few indi- sets of contacts as the center contact mance or early failure. Most hob- vidual contacts, or several sets moves from side to side; that prevents byists don't use relays very often, and ganged together. both sides of the switch from being aren't aware of features and dif- Figure 1 shows the four basic relay shorted. Sometimes a circuit requires ferences, but selecting the right one is configurations. The version in Figure that the relay contacts not be left un- no more difficult than selecting a re- 1-a is Normally Open (NO) until the connected, even momentarily, in sistor or capacitor. This article exam- coil closes it, while that of Fig. 1-b is which case Form D is used. Applica- ines relays in great detail, explaining Normally Closed (NC) until the coil tions of Form D include smooth, how they work, configurations, and opens it. Figures 1-c and 1-d use dou- noise -free switching of current -lim- applications. ble -throw contacts, arranged as ited audio or control -system signals, 59

www.americanradiohistory.com DESIGN SEQUENCE SYMBOL FORM TABLE 1 -TYPICAL RELAY CHARACTERISTICS o e STYLE DIMENSIONS CONTACT COIL, VOLTAGES SWITCHING SPST O MAKE 1A (INCHES) RATINGS AND POWER TIMES N.O. General 1.2 to 2.0 H 3 to 10 A 6, 12, 24, 120 V 15 to 30 msec Purpose 0.9 to 1.5 W 28 VDC 1.2 W DC Plug-in 0.9 to 1.4 D 120 or 240 VAC 2 VA AC

General 0.4 to 0.7 H 1 to 5 VA 5, 6, 12, 5 to 10 msec SPST BREAK 18 N.C. Purpose 0.6 to 1.2 W 28 VDC 24, 48 VDC Miniature 0.4 to 0.75 D 120 or 240 VAC 0.5 to 1 W

Reed 0.3 to 0.5 H 0.5 to 2 A 5, 6, 12, 24 VDC 0.2 to 1 msec 0.9 to 1.2 W 5 to 50 W 50 to 400 mW

ro D 28 to 250 VDC (Coils to 1 V BREAK(1), 0.3 0.8 SPDT 1C MAKE(2) Also available & AC available) in a DIP format

Hermetic 0.3 to 0.9 H 0.5 to 5 A 4 to 32 VDC 5 msec

TO -5 0.6 to 1 W 28 VDC 120 mW 1 0.3to0.5D 115 VAC

2i o Hermetic 0.3 to 0.9 H 0.5 to 2A 5 to 115 VDC 5 msec and other 0.6 to 1 W 28 VDC 100 to 400 mW BREAK(1,3), DPDT 2C sealed 0.3 to 0.5 D 115 VAC MAKE(2,4) RF 0.4 to 1 H 10 to 25 W RF 5 to 50 VDC 5 to 10 msec 0.8 to 1 W hot To 150 W 250 mW

0.4 to 1 D RF dry Power Dimensions 10 to 40 A 6, 12, 24, 120 15 to 50 msec typically 120, 240 VAC 208, 240 V 2 to 4 inches & higher 2 to 5 W DC MAKE(1) 6to20VAAC SPDT 2 BEFORE 10 BREAK(2)

FIG. 1 -RELAY -CONTACT arrangements dimension is about 2 inches, and its Coil voltages from I-24 volts are are designated as Forms A -D. Form A is dust cover provides a little protection, available, with operating power de- normally open until the coil closes it, but the relay isn't sealed. Miniature mands at a fraction of a watt. while Form B is normally closed until the Probably the smallest coil opens it. Forms C and D use double - general-purpose relays are epoxied commonly throw contacts, arranged as break -before - into rectangular plastic potting shells, available models are the TO -5 ver- make (Form C) or make -before -break and have PC board pins. Typical di- sions. Some look just like transistors; (Form D). mensions are about 1 inch, and their others are square. The overall diame- controls can typically switch 1-5 am- ter or width is about 0.3 inch with or avoiding voltage spikes when peres. switching inductive loads (more Reed relays like those in Hg. 3 can later). Naturally, Form -D contacts either be open or encapsulated, and can't switch between two sources are generally PC board -mounted when shorting them could result in DIP's. Figure 4 shows a single mag- disaster. netic reed switch relay; very often, there's more than one inside a given A variety of styles model. The magnetic field brings the Relays switch signals ranging from reeds together, and they're sealed in a microwatts of RF to megawatts of glass envelope to protect them from power; size can vary as much as con- contamination. Reed relays switch struction techniques. The design var- very fast (500 µsec), compared to ies with the application. Probably the 5-30 msec for general-purpose types. most familiar relays are general-pur- Reed relays are intended for dry pose and reed versions. Table 1 sum- contact (as opposed to mercury wet- marizes the most common types. ted) and low -power switching. Typ- Figure 2 shows a typical general- ical contact ratings are 200-250 volts, purpose plug-in relay with socket. 10-30 watts of switched power, with This type switches moderate power, low voltage current ratings of 0.5-2 10-30 amperes at 120/240 volts AC. amps. Reed relays with up to six poles sockets with circular are High Octal tube -type available. -voltage models FIG. 2 -MANY GENERAL-PURPOSE re- pins are also available, as well as the switch up to 1 kilovolt, while mercury lays use sockets, like this Potter and flat -blade version shown. Its largest reed relays typically switch 100 watts. Brumfield unit.

www.americanradiohistory.com sealed relays don't need corrosion resistance, but are often made of precious metals like rhodium or ruthenium. Power -switching relays need large contacts actuated with sufficient force to handle high currents and voltage. Arcing must be minimized, and electrical and thermal resistance must be low to minimize heating; button contacts are normally used. High -power versions normally use silver -cadmium oxide; it resists welding, has FIG. 3-REED RELAYS come in a variety of packages. They're usually small, PC board - good arc -extinguishing charac- mounted DIP's about 1 inch long. teristics, and is well suited for reactive or high -surge current loads, but not for switching voltages under 12 volts. AXIAL LEADS ALLOW VARIOUS NICKEL PLATED STEEL JACKET is for medium -power MOUNTING CONFIGURATIONS /PROVIDES MAGNETIC SHIELDS Silver good loads and communication systems, but not under 6 volts. Since silver oxidizes easily, such contacts should

ENDS EPDXY SEALED TO PROVIDE END FLANGE FOR COIL WINDINGS ON REED SWITCH FOR ENVIRONMENT PROTECTION COIL WINDING RETAINER INCREASED ELECTRICAL EFFICIENCIES GENERAL ELECTRIC 3SAV] 761,42 FIG. 4-AN HERMETICALLY -SEALED reed switch actuated by magnetic coil; the coil's COIL OHMS 47 magnetic field brings the reeds together. Reed relays can switch in 500 µsec, compared to MADE IN .. 5-30 msec for general-purpose relays. wire leads coming out the bottom of a relays, but are specially constructed 0.2 -inch diameter circle. The contact for heavy-duty switching. The con- specs are more limited than those for tacts are moved by a solenoid that reed relays, typically 28 -volts DC or exerts considerably higher force than

120 -volts AC at about 1 ampere. Coil is normally used in non -power relay power is a fraction of a watt at up to applications, instead of a fixed -core 32- volts DC, and sometimes a little coil. higher. They're hermetically sealed and work from - 40-125°C. Some Choosing the right contacts are available with built-in drive tran- Obviously, low-level relays can't FIG. 5-THIS G.E. CORP. hermetically- sistors and/or diode surge suppres- switch power, and, conversely, power sealed relay matches the characteristic RF impedance of a 50-ohm transmission sion. relays won't reliably switch low-level line over the frequency range 500 MHz -2 Larger sealed relays switch up to 5 signals. Contact choices are shòwn in GHz, and uses coaxial connectors instead amperes. Housings include crystal - Table 2. The right contacts are crucial of pins. Typical contact ratings are 150 cans and plug-in housings. The her- for reliable operation. Power loads watts. metically -sealed RF relay with coax- have self-cleaning contacts that have a ial connectors in Fig. 5 matches the tendency to arc and burn off oxidation 50 -ohm impedance of most transmis- or contamination. Low-level "dry" sion lines at frequencies from 500 (non -wetted) circuits don't do that, MHz -2 GHz, depending on the and have to be clean; even a thin layer model. Contact ratings of 150 watts of contamination can prevent low- are typical. level signals from being switched. Power -switching relays are larger, Dry -circuit contacts use non -ox- almost always use open construction, idizing materials or platings, operate and are used to switch all power levels with a wiping action so the contacts up to multi -megawatt levels. Figure 6 slide past each other, and are bifur- shows a typical relay used in a power cated (two branching parts). That application like motor control. Over- means that a lengthwise slot in the all dimensions of versions switching middle of the contact splits it into two up to 30 amperes are 2 -4 -inches. parts for the sake of electrical redun- FIG. 6-POWER RELAYS, switching up to use con- Typical coil power is about 2 watts dancy. Low-level bifurcated wiping 40 amperes, normally open gold- struction, for motor control. Overall di- DC or 5-10 volt-amperes AC. "Con- relay contacts are typically mensions of 30 -ampere versions are 2 -4 - tactors" for switching large motors plated, or use other precious metals. inches, and typical coil power is about 2 provide the same function as power The contacts in reed or hermetically - watts DC or 5-10 volt-amperes AC.

61 www.americanradiohistory.com series, for example, is rated at 0.5 through an inductor can't be in- amp, 10 -watts DC, and 0.1 ohm, stantaneously stopped. If a coil is o L1 S1 D1 using dry contacts; the mercury -wet- opened while current flows through it, (LOAD) ted equivalent is rated at 2 amps, 50 - its magnetic field collapses rapidly, I B1 II watts DC, and 0.05 ohm. Contact life inducing a large voltage, the polarity is higher as well for mercury versions, of which maintains current flow.

a although they have to be maintained That's the principle used in auto- in particular positions. motive ignitions or TV flyback transformers. The voltage can reach the Contact protection kilovolt range, producing arcing and ó \St Switching inductive loads creates destroying contacts. special problems, since the current When inductive loads are switch -

V1 b

ON CLOSED OPERATING VOLTAGE CONTROL OFF L OPEN

I ENERGIZED O DELAY ENERGIZED S7 OUTPUT RELAY OUTPUT RELAY DE -ENERGIZED L DE -ENERGIZED DELAY

ON -DELAY OFF -DELAY a b c FIG. 7-WHEN SWITCHING inductive loads, surge suppression provides a cur- ON CLOSED rent decay path when relay contacts open. OFF AT For DC loads, use a reverse -biased diode OPERATING VOLTAGE CONTROL i'' ANY TIME

L i as in (a). For AC loads, use an MOV (or OFF OPEN ,I L_ resistor) and a capacitor as in (b). ENERGIZED ENERGIZED ' OUTPUT RELAY OUTPUT RELAY DE -ENERGIZED DELAY DE -ENERGIZED DELAY

INTERVAL LATCHING INTERVAL c d

CLOSED ON OPERATING r CONTROL VOLTAGE) REMOVE TO STOP OPEN OFF CYCLE & RESET CONTINUES CYCLYING DELAY 1 DELAY UNTIL POWER IS ENERGIZED ENERGIZED #1 (OFF) I REMOVED OUTPUT RELAY OUTPUT RELAY DELAY DE -ENERGIZED ' DELAY 2 DE -ENERGIZED #2 (ON)

ON-DELAY/OFF-DELAY REPEAT CYCLE FIG. 8-THIS LATCHING RELAY, the 589R from Potter and Brumfield, flips a mechanical toggle from side to side like a mechanical flip-flop, changing state when the coil is activated by a pulse. CLOSED CLOSED ,,,, OFF AT CONTROL CONTROL ANY TIME he gold plated (flashed) for storage OPEN - OPEN protection. The gold flash will wear with use, and the contacts then de- ENERGIZED ENERGIZED OUTPUT RELAY DELAY pend on wiping and burn -off for OUTPUT RELAY L cleanliness in operation. DE ENERGIZED DE -ENERGIZED DELAY ACCUMULATION Silver palladium is less susceptible LATCHING ON -DELAY to oxidation; however, its burn -off re- ACCUMULATING ON -DELAY sistance and conductivity are inferior g h to silver. It should be used only for low power, below 60 volts. In reed FIG. 9-TIME-DELAY RELAYS prolong actuation or dropout. The on -delay (a) turns on relays with mercury -wetted contacts, during the operating voltage and continues until it's removed. The off -delay (b) turns on a thin film from a small pool of mer- when the control goes high, and begins its delay after control goes low. The interval (c) cury (not the pool itself) shorts the turns on when the operating voltage appears, and off before it ends. The on/off-delay (e) has two delays referenced to the leading/trailing control pulse edges. The repeat cycle's contacts. The mercury increases film (t)second delay depends on the first. The accumulating on -delay (g) compares total power -switching capacity and de- control pulse duration with a reference. In the interval (d) and on -delay (h) latches, the creases contact resistance. One relay control pulse turns off any time.

62 www.americanradiohistory.com 1 12

1.414 times the RMS level. You can TABLE 2-CONTACT MATERIAL CHARACTERISTICS also omit the MOV and add a resistor in series with the capacitor, as shown TYPICAL in Fig. 7-c. CONTACT APPLICATIONS RATINGS COMMENTS Even without an inductive load, Bifurcated, gold- "Dry" and low 0 to 0.2 A. Rated Low, steady contact high voltages will tend to arc across plated, or gold current. to 120 VAC, but resistance. the contact as it opens. Once struck, overlay Measurement best for 24 V or the arc will continue via the ionized and signal less. air until the voltage is removed. That switching. is why many contacts rated for Silver Communications 2 to 5 A Oxidizes easily. Should 120/240 volts AC are limited to only be gold -flashed for 28 volts DC. As a cure, some larger storage protection. relays are available with a "blowout Silver cadmium Power, inductive 5 A and ur Resists welding. Good magnet" at each set of contacts. oxide and capacitive arc -extinguishing When properly installed, the magnet- loads. High in- characteristics. Less ic field deflects the arc, just as a rush currents. suited below 12 V. CRT's electron beam is deflected by Mercury wetted "Dry" and low 2 to 5 A Position sensitive. (Typ. magnetic coils, so that its path can't current, long life, vertical +1- 30 extend from one contact to the other. no contact degrees.) The arc is extinguished as soon as it bounce. forms; relays with powered blowout coils also are available.

Coil types SEALED All relays can be used with DC. CONTACT CHAMBER COIL General-purpose and power relays are also offered with AC coils. Although some use internal rectifier diodes, most use coils and magnetic structures designed for AC. In AC opera- APPROXIMATE tion, the relay switching time has to FLUX PATH be long enough so that the relay MAGNETIC doesn't "buzz" as the input voltage REED PLATE crosses zero. Most general-purpose and power relays are slow enough to DIRECTION OF ) !MAGNETIC AND REED PLATE avoid the problem. The coil is an in- ELECTROSTATIC MOTION SHIELD, GROUNDED ductor, so its current is out of phase WITH EXTERNAL with its voltage In Table 1, typical PIN PROVIDED AC volt-ampere ratings are somewhat

NO NC REED higher than the wattages of equivalent CONTACT CONTACT - MAGNETIC MATERIAL DC coils.

- INSULATING MATERIAL Specialty versions FIG. 10-THIS LOW -THERMAL -VOLTAGE reed relay uses silver conductors and pins Latching or impulse relays are me- outside the coil, gold-plated silver contacts, and careful shielding to minimize errors. chanical flip-flops, changing state when their coils are activated by a ed, surge suppression should be pro- sistor. However, the time constant for momentary pulse. They're useful in vided, by providing a current path an R C combination is: TCAP = RC, battery and low-power applications, once contacts open. For DC loads, a whereas for an inductor-resistor com- because they use power only when reverse -biased diode is often added as bination it's: TIND = L/R. Note that toggled, and they remember their in Fig. 7-a. When the contacts open, TINA is inversely proportional to R, so state during power failures. The two load current will flow until it decays to as R increases, TINA decreases. The types are the mechanical -toggle and zero. The diode's Peak Inverse Volt- size of the transient can be easily de- magnetic -reed versions. Figure 8 age (PIV) rating should exceed the termined using Ohm's Law: shows a mechanical -toggle relay; the supply voltage by at least 50%, and it mechanism is the same as that used in should have a surge -current rating VPEAK = 'LOAD X RSERIES push-on/push-off switches. The coil that is greater than the normal load Figures 7-b and 7-c show one way pulls the pin straight down, toggling curent. A resistor in series with the to provide surge suppression for an the latch to the left. When deactivat- diode causes the current to decay AC load. Fig. 7-b uses a Metal -Oxide ing, the pin moves up and rests in the more rapidly but will produce a larger Varistor (MOV) and a capacitor. The upper right-hand notch. When next voltage transient. breakdown voltage ratings of the actuated, the toggle is pulled to the You might initially expect a larger MOV and the capacitor must exceed right. resistance to impede current flow, as a the peak voltage of the AC supply. For Two -coil latching relays use one capacitor would in series with a re- 60 -Hz power, the peak voltage is continued on page 76

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More on cold fusion H ARDWARE New PostScript video linear stepper motors Stepper driver circuits H ACKER Modelmaking resources

More on cold fusion DON LANCASTER

IS COLD FUSION FOR REAL? MOST OF (8) Operation above 175 degrees Meanwhile, besides all the orig- the researchers and most of the will dramatically drop the efficien- inal German work from the early labs have loudly proclaimed "no" cy. Thus, a heat engine using some 1920's, there is an obscure 1979 after all of their initial hasty and non -water fluid, such as ammonia, Australian patent #48901/79 on misdirected experiments failed. must be used to extract useful cold fusion. But a very few labs are now more work. Fortunately, those OTEP While I personally feel that the convinced than ever that some- (Ocean Thermal Electric Power) patent appears to involve something really big is coming down. people have already done all the one who seems to be a few chips At any rate, sources very close to groundwork for low -temperature shy of a full board, it sure will be the barber of an associate of a usu- differential heat engines. interesting to see how many mod- ally reliable spokesperson for a (9) For a breakdown, excess fu- ern claims will be disallowed be- key fusion researcher feel that... sion heat production well beyond cause of that apparent prior art. (1) Cold fusion is real and is in 12:1 will probably be required, due Oh, yes, you might also want to fact the explanation for both the to the inherently low efficiency of look at US patents 3,983,882 and continuous and "burst modes" of any heat engine forced to work 4,107,008. Curiouser and curi- the excess heat production. with a low temperature differen- ouse r. (2) The tritium reaction does all tial. Thus, a little bit of excess heat On, now, to a popular help -line of the work, and enough tritium is is useless except possibly as a yup- topic... produced to exactly be able to ac- pie ski -boot heater. count for the excess heat. (10) Other candidate materials Stepper motors (3) The ambient air can poison do include zirconium, Ian- There have been a lot of helpline the reaction. Working in a very dry thanium, and titanium, but ti- requests lately for extra informa- inert argon atmosphere is recom- tanium does seem highly over- tion on stepper motors. A stepper mended. rated at present. motor differs from an ordinary (4) The palladium must be vac- (11) Yet another reasonably motor in that it rotates its shaft in a uum -refined and then recast, but priced source for heavy water is discrete and incremental stepping not in a carbon mold. Any rework, the Canadian Atomic Energy Com- motion. such as an extrusion, is a not al- mission. I do not have their ad- A stepper motor is thus ideal for lowed. dress so far. A free book if you do. any intermittent or precise mo- (5) While palladium films as thin In reality, most of those observa- tions, such as you would need for as 50 angstroms could be used, tions are straight from the horse's the platen feed on a dot matrix or any impurities at all are a no -no. whatever. Time will tell us which daisywheel printer. Steppers are Platinum impurities as low as 0.01 end of the horse we are dealing also useful for any slow -speed ap- percent spoil the material. with. plication, eliminating the cumber- (6) All bubbles must absolutely some gear trains you would need get eliminated at the palladium with most ordinary high-speed surface. Pressurizing the heavy NEED HELP? motors. The steppers are also in- water can help bunches here. stantly reversible, and usually have (7) The deuterium ions must a Phone or write your Hardware holding torque that can act as an flow through the palladium. One Hacker questions directly to: internal brake. Steppers are handy approach might be to use a sin- Don Lancaster for variable -speed uses, some- tered palladium cylinder having an Synergetics thing that gets extremely tricky to internal vacuum. Another might Box 809 do with most AC motor designs. involve a three -element cell with Thatcher, AZ 85552 One type of stepper motor con- an accelerating second anode of (602) 428-4073 sists of a toothed magnetic rotor some sort. and a toothed iron stator. The

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He'll get great plans and printed circuit No need to send money ... if you prefer, patterns for great electronic projects. In just we'll hold the bill till January, 1989. But you the last year, Radio-Electronics has presented must rush the attached Gift Certificate to us voice scramblers, video switchers, frequency to allow time to process your order and send standards, wireless audio links, radiation a handsome gift announcement card, signed monitors, function generators, and much with your name, in time for Christmas. more. In coming issues, Radio -Electronics will present practical, educational, and money- So do it now ... take just a moment to fill in saving projects like: a helium -neon laser ... a the names of a friend or two and mail the lighting controller ... a video timebase Gift Certificate to us in its attached, postage - corrector ... a video noise processor ... a paid reply envelope. That's all it takes to plug light -beam communicator ... an antenna your friends into a whole year of exciting amplifier ... and many others! projects and new ideas in Radio -Electronics! Ibitrees 446

67 www.americanradiohistory.com number of teeth decides the step angle and the number of steps per MODELMAKING RESOURCES revolution. In the absence of any electrical input, the rotor will lock AIN Plastics to the stator by seeking out paths 249 E. Sandford Blvd of minimum magnetic reluctance. Mt. Vernon, NY 10550 There are normally two groups (914) 668-6800 of windings provided. The "A" Apache Reclamation 313 W. Apache St. winding is active one-third of the Pheonix, AZ 85003 distance between teeth, while the FIG. 1-IN A BIPOLAR (OR UNIFILAR) (602) 254-0613 is a grind- "B" winding is active two-thirds of stepper motor, there only single Bead Chain the teeth. ing for each phase. Although the stepper the distance between itself is powerful and low-cost, the driver 110 Mountain Grove, PO Box K In typical use, a four -step pro- circuitry gets extra complicated, since a Bridgeport, CT 06605 cess is used to advance to the next full -bridge circuit is needed-one that is (203) 334-4124 tooth position. The A winding first able to send current in either direction. BNF Enterprises gets activated, attracting the tooth- Bipolar stepper's often have four leads. 119 Foster Street ed rotor one-third of the distance Peabody, MA 01961 (508) 531-5774 to the next tooth. Then the B wind- C & H Sales is ing activated, attracting to the 2176 E. Colorado Blvd. two-thirds point. Next, the A 0^ Pasadena, CA 91107 winding has its current reversed to (213) 681-4925 further repel towards that two Caplugs thirds point. In the final step, that 2150 Elmwood Avenue current in the B winding gets re- Buffalo, NY 14207 versed, repelling the rotor to its (716) 876-9855 new and final position. Constantine The speed gets determined by 2050 Eastchester Road Bronx, NY 10461 the number of steps applied per (212) 792-1600 second. The direction is set by FIG. 2-IN A UNIPOLAR (OR BIFILAR) Design News stepper motor, you will find a pair of wind- changing the roles of the A and B 275 Washington Street windings. ings for each phase. While that raises the cost and also reduces the available step- Newton, MA 02158 per power, your driver circuitry is far sim- (617) 964-3030 NEW FROM pler and very much cheaper, since only a EDLCO current sink is needed for each winding. A PO Box 5373 DON LANCASTER unipolar stepper often has six leads. Asheville, NC 28813 (704) 255-8765 HANDS-ON BOOKS

Hardware Hacker Reprints II 24.50 Other patterns of activating the Ask The Guru Reprints I or II 24.50 A and B windings might give you CMOS Cookbook 18.50 various speed and cost more and offer less power. TTL Cookbook 16.50 torque options, Active Filter Cookbook 15.50 as well as actually microstepping, You can usually tell which type Micro Cookbook vol I or II 16.50 the moving to a precise position of stepper you have by the number Enhancing your Apple I or II 17.50 AppleWriter Cookbook 19.50 between the rotor teeth. of leads. Assuming that all the Apple Assembly Cookbook 21.50 As Figs. 1 and 2 show us, there leads are brought out separately, a Incredible Secret Money Machine 10.50 LaserWriter Reference (Apple) 19.50 are two different methods with bipolar stepper will have four PostScript Cookbook (Adobe) 16.50 which stepper motors are com- wires, while a unipolar one will PostScript Ref. Man. (Adobe) 22.50 monly wound. In a bipolar stepper have six. For most hacker uses, the PostScript Prog. Design (Adobe) 22.50 Real World Postscript (Roth) 22.50 there is only a single A winding unipolar and bifilar windings are and a single B winding. That is the best choice, since they are UNLOCKED SOFTWARE only cheaper and has more power, but easier and cheaper to drive. LaserWriter Corner (Ile/Mac/PC) 29.50 PostScript Show & Tell 39.50 requires you to electronically Good data sheets and ap-notes Intro to PostScript VHS Video 39.50 reverse the high current through on steppers are available from PostScript Perspective Draw 39.50 PostScript Beginner Stuff 39.50 both windings. Thus, what you Airpax, Hayden, Superior Electric, PostScript Technical Illustrations 39.50 gain in stepper economy, you lose and most of the other suppliers. PostScript Work in Progress 39.50 in driver complexity. Bunches of technical articles and PostScript BBS stuff 19.50 Absolute Reset Ile & IIc 19.50 In a unipolar or a bifilar stepper, supplier ads for steppers appear in AppleWriter/Laserwriter Utilities 49.50 there are two distinct A windings the PCIM and Motion trade jour- Enhance I or II Companion Disk 19.50 AppleWriter CB or Assy CB Disk 24.50 and two separate B windings. Each nals, as well as the usual elec- of the windings go in the opposite tronics insider magazines. `FREE VOICE HELPLINE VISA/MCA sense of the other, so a current in While new steppers are usually SYNERGETICS one winding will attract the rotor, rather pricey, you can find lots of Box 809 -RE while the same current in the surplus ones in assorted sizes and Thatcher, AZ 85552 other winding will instead repel voltages for as little as $2 through (602) 428-4073 the rotor. The unipolar windings all the usual Radio -Electronics ads CIRCLE 83 ON FREE INFORMATION CARD are much easier to drive, but they and similar surplus sources.

68 www.americanradiohistory.com Edmund Scientific K & S Engineering Plastiglide 101 E. Glouchester Pike 6917 West 59th St. 2701 West El Segundo Blvd. Barrington, NJ 08007 Clicàgo, IL 60638 Hawthorne, CA 90250 (609) 573-6250 (312) 586-8503 (213) 777-8108 Evergreen Scale Models Lindsay Publications Signcraft 12808 NE 125th Way PG Box 12 1938 Hill Ave. PO Box 06031 Kirkland, WA 98034 Bradley, IL 60915 Fort Meyers, FL 33906 (206) 823-0458 (815) 468-3668 (813) 939-4644 Fastex Machine Design Sinclair & Rush 195 Algonquin Road 1100 Superior Avenue 10315 Page Industrial Blvd. Des Plaines, IL 60016 Cleveland, OH 44144 St. Louis, MO 63132 (312) 299-2222 (2`6) 696-7000 (314) 426-4487 Fine Scale Modeling McMaster -Carr Small Parts 21027 Crossroads Circle Bcx 54960 6891 NE Third Ave. Waukesha, WI 53187 Los Angeles, CA 90054 Miami, FL 33238 (414) 796-8776 (2-3) 692-5911 (305) 751-0856 Fomeboards Miled Shapes Special Shapes 2211 N. Elston Avenue 17)1 North 33rd Ave. PO Box 487 Chicago, IL 60614 Melrose Park, IL 60160 Romeoville, IL 60441 (312) 278-9200 (312) 344-1220 No listing W.W. Granger Model Railroader Stock Drive Products 5959 West Howard St. 21327 Crossroads Circle 55 South Denton Ave. Chicago, IL 60648 Waukesha, WI 53187 New Hyde Park, NY 11040 (312) 647-8900 (414) 796-8776 (516) 328-0200 Herbach & Rademan New Equipment Digest Synergetics 401 East Erie Avenue 11)0 Superior Avenue Box 809 Philadelphia, PA 19134 Cleveland, OH 44114 Thatcher, AZ 85552 (215) 426-1700 (216) 696-7000 (602) 428-4073 Hygenic Manufacturing Northeastern Scale Models US Plastics 1245 Home Avenue PO Box 727 1390 Neubrecht Road Akron, OH 44310 Msthuen, MA 01844 Lima, OH 45801 (216) 633-8460 (508) 688-6019 (419) 228-2242 Jerryco Nuts and Volts oodworker's Store 601 Linden Place Box 1111 21801 Industrial Blvd. Evanston, IL 60202 Placentia, CA 92670 Rogers, MN 55374 (312) 475-8440 (714) 632-7721 (612) 428-2899

Two linear steppers of force in 2 -mil (0.002 inch) incre- but you might be able to find one Take an ordinary stepper motor, ments, over an 8 -inch actuating nearly free at your local junkyard, but make it hollow at its center. length. as some automobiles use them for Then add a threaded shaft through While under $20 in quantity, sin- computerized carburetor idle ad- the middle, which gets driven gle evaluation units cost around justments. Unfortunately, I don't from a nutplate on the stepper ar- $55, unless you can locate a sur- know which specific models to mature. As the stepper is stepped, plus one. That seems rather high, send you after. There are also the nutplate turns, which in turn until you take that "Uh, compared some plain old throttle solenoids advances or retards the threaded to what?" factor into account. that look just about the same, so shaft. On custom order, lead screws make sure you are getting a "real" All of which gives you a way to up to several feet long can be ob- stepper when you make your visit. push or pull things in tiny and very tained. Note that there is no the- You can step them up to 400 accurate increments under com- oretical limit to the stroke you steps per second, which means puter control. With lots of force could get out of one of those, so you can travel the half -inch stop - over fairly long strokes. long as a lead screw that length is to -stop distance in something like Uses? Animation tables, available. Maintaining the preci- 0.6 seconds. But you do lose force printed -circuit drills, a numeric - sion and avoiding any binding at the higher stepping rates. controlled milling machine, plot- would, of course, get far worse We're using that one locally to ters, robotics, valve actuators, with increasing length. adjust the teeth on a cotton pick- electronic engine controls, re- Figure 4 shows you a smaller ing machine. The stepper acts as search projects, point -of -pur- Airpax series 92100 unit. They are sort of a micrometer, advancing chase displays, plus dozens of much smaller and give you a half - until it touches each tooth. The uses previously unthunk of. inch maximum stroke, in 2- or 4 - number of steps needed then tells Figure 3 shows you the Hurst mil steps, having a force slightly the mechanic how much shim to model SLS linear actuator. It's a 12 - over one pound. add. watt unit that gives you 25 pounds The price is around $25 each, If you don't know anything

www.americanradiohistory.com nal protection for both overheat- ing and overcurrent. They are well under $4 in singles. To use the circuit, you provide two inputs. The first is the direction input which decides whether your stepper will spin forward or backward. The second is a train of square -wave pulses that sets the speed in the chosen direction. It is usually best to computer control your stepper driver. As we've seen, an otherwise unused Commodore 64 is ideal for that sort of thing, and their going rate is around $30 at a yard sale.

One microcontroller chip that I really like which includes dual low-level stepper drivers on -chip (among lots of other goodies) is the great M50734 by Mitsubishi. That dude cross -assembles FIG. 3-THE HURST SLS LINEAR ACTUATOR is a real "sleeper" for hardware hacking. beauti- This easy -to-drive 12-volt, 12 -watt unit offers 24 pounds of force in 2 -mil (0.002) incre- fully on an Apple Ile or Ilgs. ments. What can you do with it that's new and really different? Three contests ry for their devices, but those tend Let's have three contests this to be older hybrids that seem over- month. There will be the usual priced. Instead, there are several Incredible Secret Money Machine suppliers of single- and double - prizes for the best dozen entries, chip stepper-motor drivers. They with an all -expense paid (FOB include Sprague, SGS, and Thatcher, AZ) tinaja quest for two Motorola. going to the very best of all. Figure 5 shows you a circuit for For the easy contest, just tell me the Sprague UCN-4204B single - something you would like to do

chip stepper driver. While I with a linear stepping motor or a haven't yet been able to check the linear actuator. Or two or even chip out (stay tuned), it looks like a three. Especially if they have twen- typical modern circuit with 1.5 ty pounds of force in 2 -mil incre- Ce amps of drive capability and inter- ments.

SPEED Nan_ INPUT °

FIG. 4-THE AIRPAX 92100 is a smaller DIRECTION INPUT linear stepper motor having a 1/2 -inch +5V stroke. Similar units may be available at a m0m®®mm0 junkyard as throttle idle controllers. VCC ENI DIN GND GND SIN ENS END 4204B STEPPER DRIVER IC about cotton picking, what we GA VM 0A GND ONO OB VM OB have here is an easy and precise 0000 000 a way to eliminate most tedious heatsink all GND pins. and time-consuming job. If the teeth are too close, you destroy the machine. If they are too far +12V o away, your yield and your grade goes down. A third source of linear actuators is Eastern Air Devices, but their military look and their refusal to UNIPOLAR include pricing in their mailings STEPPER does not bode well for hackers. MOTOR

Stepper drivers Most of the stepper manufac- FIG. 5-LOW-CUST SINGLE -CHIP stepper -motor drivers are readily available from turers have available driver circuit- Motorola, SGS, and Sprague, among others. Here's a popular Sprague driver.

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to use voltmeter, understand DC electronics)... . (203) 756-7441 (714) 855-0819 IF you possess average mechanical ability, and have a Heath Buyers Club SGS VCR on which to practice and learn. ...then we can PO teach YOU VCR maintenance and repair! box 217 100 East Bell Rd. FACT: up to 90% of ALL VCR malfunctions are due to Benton Harbor, MI 49022 Phoenix, AZ 85022 simple MECHANICAL or ELECTRO -MECHANICAL (616) 982-3789 (602) 867-6959 breakdowns! Hurst FACT: over 77 million VCRs in use today nationwide! Manufacturing Sprague Average VCR needs service or repair every 12 to 18 Box 326 363 Platinum months! Princeton, NJ 47670 Worcester, MA 01605 Viejo's 400 PAGE TRAINING MANUAL (over 500 pho- (812) tos and illustrations) and AWARD -WINNING VIDEO 385-2564 (508) 795-1300 TRAINING TAPE reveals the SECRETS of VCR mainte- Linear Technology Superior Electric nance and repair-"real world" information that is 1630 Mc Carthy Blvd. 383 Middle St. NOT available elsewhere! Milpitas, Also includes all the info you'll need regarding the CA 95035 Bristol, CT 06010 BUSINESS -SIDE of running a successful service op- (408) 432-1900 (203) 582-9561 eration! Mitsubishi Tektronix FREE INFORMATION CALL TOLL-FREE 1-800-537-0589 1050 East Arques Avenue Box 4600 Or write to: Viejo Publications Sunnyvale, CA 94086 Beaverton, OR 97076 3540 Wilshire BL. STE 310 (408) 730-5900 (800) 426-2200 Los Angeles, CA 90010 Dept RE CIRCLE 176 ON FREE INFORMATION CARD 72 www.americanradiohistory.com Rates: Ads are 21/4" x 21/t". One insertion $900. Six insertions $875. each Twelve insertions $845.each. Closing date same as regular rate card. Send order with remittance to Engineering Admart, Radio Electronics Magazine, 500-B Bi -County R -E Engineering Admart Blvd., Farmingdale, NY 11735. Direct telephone inquiries to Arline Fishman, area code -516-293-3000. Only 100% Engineering ads are accepted for this Admart.

MIDI LINEAR IC EQUIVALENTS Projects FCC LICENSE & PIN CONNECTIONS MIDI Linear IC Equivalents PREPARATION and Pin PROJECTS Connections The FCC has revised and updated the commercial license exam. The NEW EXAM covers updated marine an BP182-MIDI interfacing enables any so aviation rules and regulations, equipped instruments, regardless of the transistor and digital circuitry. manufacturer, to be easily connected to- THE GENERAL RADIOTELEPHONE gether and used as a system with easy com- OPERATOR LICENSE - STUDY GUIDE & pin con- puter control of these music systems. BP141-Shows equivalents contains vital information. VIDEO Combine a computer and some MIDI instru- nections of a popular user -oriented SEMINAR KITS ARE NOW AVAILABLE. ments and you can have what is virtually a selection of European, American and programmable orchestra. To get your copy Japanese liner IC.'s 320 pages, 8 x 10 WPT PUBLICATION send $6.95 plus $1.25 for shipping in the inches. $12.50 Plus $2.75 shipping. 979 Young Street, Suite A U.S. to Electronic Technology Today ELECTRONIC TECHNOLOGY TODAY Woodburn, Oregon 97071 Inc., P.O. Box 240, Massapequa Park, INC., PO Box 240, Massapequa Park, Phony (503) 981-5159 NY 11762-0240. New York 11762-0240. CIRCLE 177 ON FREE INFORMATION CARD pecially when it comes to cheaply hacker modelmaking, seven of sheet stocks especially designed finding, shearing, and bending your "must have" publications infor models and mockups. One any heavier metal. You might want clude Model Railroader, Fine Scale leading distributor of those mate- to substitute an air-conditioning Modeling, Design News, Machine rials is Fomeboards. outfit, a welder, or even a black- Design, Nuts and Volts, Signcraft, Several random companies do smith shop here. and the New Equipment Digest. fall into the "neat stuff" category, At any rate, one resource stands Don't tell NED who told you about making them extremely valuable out head and shoulders above all all their great free samples each resources for modelmaking. Some others for hacker modelmaking. month. of them include Hygenic for rub- That is Small Parts, who stock ev- For a wide-ranging assortment ber sheeting and tubing; Caplugs erything your hardware store nev- of fairly priced books on all as- or Sinclair and Rush for all sorts of er heard of, besides custom - pects of prototyping and model - unique closures; Plastiglide and cutting small pieces of metal and making, Lindsay Publications is a ITW Fastex for unusual plastic plastic for you. All at fair prices, good choice. items; Bead Chain for themselves; selling to anyone, with very low For all the materials themselves and US Plastics for plastic stock. minimum orders. in smaller sizes, try K&S for metal Other obvious cheap plastic A second major resource would sheet, rod, and tubing; the sources are the Lexan glazing have to be JerryCo, who have a Evergreen folks for custom -cut vi- sheets from any local glass cutter. mind -boggling assortment of low- nyl; NorthEastern for wood If you have any modelmaking fa- priced mechanical and electronic shapes that are precision precut vorites of your own, please let us surplus stuff. Competitors to Jer- into the magic sizes favored by know so we can pass them on. ryCo include Edmund Scientific, model railroaders, architects, and BNF Sales, Herbach and Rademan, doll -house builders; and Milled New tech literature and C&H Sales. And don't forget Shapes for any miniature brass ex- A design for a hackable very - about the many other superb Ra- trusions. low -noise FET amplifier appeared dio -Electronics advertisers. For larger wood stuff, check into in the June 1989 Review of Scien- The "super hardware stores" The Woodworker's Store, Con- tific Instruments on page 1194. It is that industry shops at include stantine, or Edlco. Nothing sharp- claimed to be 100 times better than McMaster-Carrand W.W. Granger, ens up a prototype case better anything else available. Other both of whom have warehouses in than making it from an exotic sources of low -noise amplifier info Precision Monolithics, most major cities. I guess I'd have wood such as Bocote, Wenge, Co- include to also include Stock Drive Prod- cobolo, or Padouk. Burr Brown and Linear Tech- ucts here for timing belts, gearing, It used to be that cardboard was nology. and such, although their pricing is cardboard and posterboard was Rohm has a pair of new data often on the high side. posterboard. But today, there are books available on all their abso- hacker inte- While I know of no magazine or dozens of easily worked, sturdy, lutely outstanding trade journal aimed directly at light, and good-looking high-tech continued on page 97 73 www.americanradiohistory.com AUDIO UPDATE

The sound of CD-Part LARRY KLEIN, AUDIO EDITOR

THE ADVENT OF THE DIGITAL COMPACT fidelity fundamentalists who pub- ters. In the comparative measure- disc was greeted by the major au- lished and read such underground ments, the CD's showed broad dio companies as the ultimate magazines as Absolute Sound and response peaks of about 2 dB ex- achievement of the audio art, the Stereophile were not going to sup- tending from about 2 kHz right up final step in the long and arduous port CD. For those golden -eared to perhaps the high -frequency march toward absolute recording self-appointed defenders of musi- limits of the program. The audible fidelity. In their view, the dawn of cal virtue, digital recording and effect of that type of response digital meant that we no longer playback was obviously the work curve is certainly enough to trig- would be troubled by clicks, pops, of nefarious forces. And their anti- ger the complaints-but where hiss, and the other extraneous digital bias was backed up by a did it come from? Was it an artifact noises heard with LP's and tapes. group of recording engineers who of CD processing? Ironically, the Furthermore, wow and flutter and had financial and emotional in- hump in the CD response occurs the other playback -speed irreg- vestments in older technology- because of LP processing! ularities inherent in all turntables including direct -cut (no tape) disc When preparing an LP master and tape decks disappeared masters. tape, mastering engineers typ- through the magic of digital pro- ically program equalize to "pre - cessing. Distortion was reduced to Justified complaints compensate" for the normal high - the vanishing point, and dynamic One can't be a frequent reader frequency losses that occur in the range approached that of live mu- of U.S. and British audio publica- disc -mastering and playback pro- sic. In short, the sonic millennium tions without quickly becoming cess. But when the same equal- had arrived. aware of their occasionally tech- ized master tape is used for the Audio old-timers, such as my- nically nonsensical views and eval- compact disc-which does not self, usually assume a wait -and -see uations. As a result, I've learned to suffer equivalent high -frequency attitude when faced with extrava- be somewhat cynical about their losses-the inappropriate high - gant audio claims. But in the case judgments as to what sounds frequency boosts are heard during of the compact disc, the fidelity good, what doesn't, and how it got playback as harshness. claims seemed solidly based on that way. So, considering the It may seem hard to believe that accepted and well -understood (by sources, my initial reaction was to incompetent audio engineering some) digital technology. So it disregard all the complaints about resulted in the release of so many

seemed that Audio Utopia was fi- CD harshness-until I began to harsh -sounding CD's, particularly nally within our grasp, right? hear it myself! since the ultimate success of the Wrong! No sooner had compact The more vociferous CD critics new CD format was to a large de- discs and their players reached the claimed that the problem was in- gree dependent on its superior marketplace then the complaints herent in the digital format. After sound quality. But the explanation started. We were told that CD re- all, how could anyone expect any- seems reasonable to me, consider- cordings sounded shrill, harsh, thing musical to survive being ing my experience over the years unmusical, lifeless, or clinical; chopped into millions of digital with lousy sounding LP's from ma- that they lacked warmth and bits and then reassembled as a se- jor record companies when their depth; and, in general, were an ries of smoothed -over adjacent engineers were not contending insult to the critical ear. If many of square waves? But disregarding with a new technology. the complaints sounded familiar, it the theories advanced by the tech- In any case, proving that the was because we had heard them nically ignorant, exactly what was spurious boost is the cause of the before-used by lovers of tube going wrong? harsh, gritty quality troubling early equipment (vacuuphiles?) to de- Several investigators compared CD's is a fairly simple task. All that scribe transistor amplifiers. some of the harsh -sounding early is needed is an octave -band equal- It became clear early on that the CD's to LP's cut from the same mas - izer to pull down the response

74 www.americanradiohistory.com Radio- where incompetent engineering has boosted it. When that's done, Electronics Mrirät=3 _oe CD's and LP's sound very much the same, except that CD's lack the spurious LP noises-and may not have the desired level of stereo ambiance.

The difference signal The moment -to-moment differences between the right and left channels of the stereo signal provide the sense of space and ambiance around the recorded per- THE MODEL WTT 20 IS ONLY THE SIZE OF formance. By manipulating the A DIME, yet transmits both sides of a tele- FREE CATALOG OF HARD -TO -FIND phone to any FM radio with TOOLS is packed with more than 2000 L-R (Left minus Right) difference conversation crystal clarity. Telephone line powered - never quality items. Your single source for precision signal equipment, designers can needs a battery! Up to''/4 mile range. Adjusta- tools used by electronic technicians, engi- artificially widen the sonic sound ble from 70-130 MHZ. Complete kit $29.95 neers, instrument mechanics, schools, labo- stage, create enhanced ambiance, +$1.50 S + H. Free Shipping on 2 or more! ratories and government agencies. Also COD add $4. Call or send VISA, MC, MO. contains Jensen's line of more than 40 tool or even produce a rear ambiance DECO INDUSTRIES, Box 607, Bedford kits. Send for your free copy today! JENSEN channel. It has usually been as- Hills, NY 10507. (914) 232-3878. TOOLS INC., 7815 46th St., Phoenix, AZ sumed that the recording process 85044. (602) 968-6231. doesn't appreciably affect the L-R CIRCLE 127 ON FREE INFORMATION CARD CIRCLE 115 ON FREE INFORMATION CARD signal aside from the slight (and inaudible) loss of separation resulting from the transfer from master tape to disc or cassette. Why, then, should listeners comparing a CD to an LP sometimes report a loss of ambiance and "air" surrounding the per- formers? The most likely explanation is that the cutter head in the mastering studio and/or the pho- ZENITH SSAVI UHF or VHF for U.S. and no cartridge in the listener's rec- abroad, reconditioned, from $179. Final ord player exaggerates the vertical CABLE TV CONVERTERS AND DE - closeout, on cable TV equipment including modulation in the record groove SCRAMBLERS SB -3 $79.00 TRI -BI $95.00 Oak N -12s, HLD-1200s, Sylvania 4040s, that carries the L-R information. MLD-$85.00 M35B $89.00 JRX-DIC $129.00 starbases, converters & more; call for list. Thus, paradoxically, the Special combos available. We ship COD. RADAR speed guns & systems for car, snow- slightly Quantity discounts. Call for pricing on other mobile & boat racing, skiing, etc. Professional lower level (-1 dB or so) of dif- products. Dealers wanted. FREE CATALOG. X & K band models $279 and up. Cash & ference signal on the CD corre- We stand behind our products where others quantity discounts. AIS SATELLITE, INC., sponds more accurately to the fail. One year warranty. ACE PRODUCTS, 106 N. 7th St./R, Perkasie, PA 18944. Or- P.O. Box 582, Saco, ME 04072 (207) ders & catalogs: 1 -800 -AIS -2001; tech. master tape than does the LP. How 967-0726. info: (215) 453-1400. does cassette or open -reel tape CIRCLE 75 ON FREE INFORMATION CARD CIRCLE 81 ON FREE INFORMATION CARD enter into the picture? Perhaps the tape's wider separation audibly compensates for the lack of vertical modulation enhancement. Bob Carver, who supplied me with some of the above data, has built into several of his Carver Cor- poration CD players a "Digital Time Lens" that regenerates the lost L-R signal and simultaneously equalizes the unwanted high -frequency boost out of harsh CD's. APPLIANCE REPAIR HANDBOOKS-13 For CD's without problems, the SIMPLY SNAP THE WAT 50 MINIATURE FM volumes by service experts; easy -to - circuit can be switched out. TRANSMITTER on top of a 9v battery and understand diagrams, illustrations. For major Now that we've resolved the hear every sound in an entire house up to 1 appliances (air conditioners, refrigerators, question (Ha!) of the sound of mile away! Adjustable from 70-130 MHZ. Use washers, dryers, microwaves, etc.), elec. compact discs, next month we will with any FM radio. Complete kit $29.95 + housewares, personal -care appliances. Basics of solid state, setting up shop, test examine the sound of CD players. $1.50 S + H. Free shipping on 2 or more! COD add $4. Call or send VISA, MC, MO. DECO instruments. $2.65 to $7.90 each. Free Do they all sound essentially alike, INDUSTRIES, Box 607, Bedford Hills, NY brochure. APPLIANCE SERVICE, P.O. Box as many critics claim? R -E 10507. (914) 232-3878. 789, Lombard, IL 60148. (312) 932-9550. CIRCLE 127 FREE INFORMATION CIRCLE 84 ON FREE INFORMATION CARD ON CARD 75

www.americanradiohistory.com and trailing control -pulse edges. The MAKE RELAYS MONEY repeat cycle version of Fig. 9-f has IN YOUR OWN continued from page 63 two delays, the second dependent on the duration of the first. The on -delay ELECTRONICS coil to latch and a second to reset. relay of Fig. 9-g finds the area under REPAIR BUSINESS! Carrying the latching idea one step the pulses of the control by integra- Stereos, TVs, VCRs, PCs...if you enjoy fix- further, a coil, a ratchet, a cam, and tion, which in this case is directly ing them, we'll show you how to start several sets of contacts can be com- proportional to total control -pulse du- your own business. It's all spelled out in THE ENTREPRENEUR'S ACTION KIT, bined to create an impulse -driven se- ration, and compares this accumu- the no-nonsense guide to starting and quencing relay. The cam is usually cut lated value to a reference to determine running a small business successfully. to provide a specific switching se- when to energize the output relay. The This remarkable, new desktop reference set is the only small business start-up guide quence for controlling operations; a output pulse -duration is independent you need to go into business for yourself! home -appliance example might be a of its turn -on time. Finally, in the Complete! Concise! Easy-to -use! washing machine. latching on -delay version of Fig. 9-h, Learn it all from our expe In a magnetically-latched reed re- the control pulse can turn off at any Accounting, Personnel Choosing a Location lay, a small permanent magnet goes time. Time Management inside the coil. The magnet is strong In the past, the delay was mechan- Getting Financing/ enough to hold the reeds together ical, but is now Start -Up Money usually electronic, Advertising once in contact, but not strong enough usually a variation on a monostable and More! to pull them together initially. Ener- multivibrator. Mechanical time -delay gizing the coil with one polarity adds relays used inertial masses for frac- to the field and closes the reeds, tion -of-a -second delays, and motor- which remain closed until the coil is driven mechanisms for delays ranging Bu Bu fit: Rutiincs. energized with the opposite polarity. from seconds to hours. Thermal cm For applications where reversing coil mechanisms, less expensive but less

8 SOFT-COVER TEXTS polarity is inconvenient, two -coil accurate, were also used; some ver- 8 CASSETTE TAPES & latching reeds can be used. A similar sions are still available. 7 SPECIAL SUPPLEMENTS idea using a weaker magnet is some- Timing relays have progressed to 2 FREE GIFTS IF YOU ORDER NOW! times used in non -latching "polar- the point now of including micro- (See for coupon details) ized" relays to improve efficiency. processors, crystal timing, and 30 -Day No -Risk Guarantee Assures Your Satisfaction! The magnetic field reduces the coil thumb -wheel control. Those relays You have 30 days to examine the Entre- current needed to actuate the contacts, provide variable latching interval each preneur's Action Kit. If for any reason, but is weak enough to release them time the input goes high, various you decide it's not for you, simply return it to us for a full refund. But keep "Money once the coil is deenergized. counting modes, and other functions. Sources"-the special guide on financ- The IC relay, recently introduced Finally, low-offset reed relays mini- ing-plus the cassette Money Talk" as by Aromat, uses an IC, a capacitor, mize errors when switching millivolt your 2 FREE GIFTS, just for reviewing the complete set. Order and a latching reed in a single pack- and microvolt DC signals, providing today! age. The IC uses the capacitor to optimum accuracy in data acquisition o THIS IS THE pulse the relay, latching when a con- systems which switch signals from ENTREPRENEUR'S trol input goes high and resetting low-level transducers such as ther- ACTION KIT when the control goes low. Since coil mocouples and strain gauges. Figure CALL NOW power is drawn only when pulsed, 10 shows one such device by Ther- 1-800-942-8800 average power use is very low. Time- mosen, Inc. The contacts are outside DEPT. RAIAA9 delay relays provide delay in actua- the magnetic coil, eliminating the And Charge it to Your VISA, MC, AMEX! tion, dropout, or both, as shown in need for magnetic -alloy contacts, and or Mail Coupon Today! Fig. 9. permitting high -conductivity gold- The on -delay relay of Fig. 9-a pulls plated silver contacts to be used. National Learning Systems in during the operating voltage and One major problem in switching Dept. RAIAA9 remains energized until the 925 Oak Street, Scranton, PA 18515 operating and handling low-level DC signals is voltage is removed. Off-delay relays unwanted thermocouple voltages. YES! Rush me the Entrepreneur's Action Kit! If not completely satisfied, I'll return it within 30 days for a as in Fig. 9-b need continuous power Any connection of unlike conductors full refund, but keep the financing guide, "Money as well as a control input, energizing forms a thermocouple, a Sources" and the cassette, "Money Talk" as my FREE generating GIFTS. I've enclosed $49.00 for the complete set, immediately after the control goes voltage varying with temperature. plus $2.25 postage and handling (PA and CA high, and beginning their turn-off de- the residents add $2.94 sales tax). Usually, internal conductors are D Check or money order enclosed lay after the control goes low. Interval silver and the pins are silver alloy. The Charge my VISA D MC AMEX relays, as in Fig. 9-c, energize imme- external pin -to -copper connections Card # diately on the appearance of the oper- are located close together to ensure Expiration Date voltage, Signature ating and turn off prior to the equal temperatures and thermocouple end of the operating voltage. In the voltages. Internally, the physical sep- NAME latching -interval type of Fig. 9-d, the aration of the contacts and the coil ADDRESS APT# control can turn off any time. minimizes heat in the conductive CITY In the on-delay/off-delay version of path. The manufacturer states that the STATE ZIP Fig. 9-e, there are two independent relay introduces a net thermal offset of ( ) delays, each referenced to the leading less than 1µV. R -E Lhone .31 Pi A Subsidiary of National Education Corporation 76 CIRCLE 183 ON FREE INFORMATION CARD www.americanradiohistory.com #1111OMMII ftadue Ihaek Parti PIaeé" WE HAVE WHAT YOU NEED FOR HOLIDAY PROJECTS! New Battery "Hotline" Service-Hundreds of Types Available We Can Now Supply Virtually Any Currently Manufactured Battery! . r.-...

In addition to our large in-store stock, Radio Shack can now supply almost any battery. Our expanding selection even includes special communications batteries for walkie-talkies and pagers. Batteries are sent from our warehouse to the Radio Shack near you. And there's never a postage or handling charge.

For Damage -Free IC Handling RS -232 Connectors, Accessories

(2)

(2) _ _ c (6) (3) (4) (1) (2) Solder -Type D -Sub Connectors Type Cat. No. Each Type Cal. No. Each (4) Inline RS -232 Tester. Spot line problems fast. #276-1401 (1) IC In/Out Tool Kit. For 6 to 40 -pin (4) Static -Draining Wrist Strap. With Male 9 276-1537 99 Male 25 276-1547 1.49 14.95 DIPs. #276-1581 6 95 24" ground lead and mini alligator clip. Female 9 276-1538 1.99 Female 25 276.1546 2.49 (5) NEWT Shielded Stunt Box. Wire in- (2) IC Pin Aligner. #276-1594 ... 2.99 #276-2397 3 29 (3) Me al-Shie ded Connector Hoods. cluded PC board to suit. #276-1403, 9.95 (3) Conductive Foam. 5 x 5" safety mat (5) Soldering Heat Sink., Prevents heat 9 -Posit on. #276-1508 2 19 (6) NEW! DIP Shunts. for your bench. #276-2400 1 29 damage. #276-1567 1 39 25 -Position. #276-1510 2 79 #276-1512 Pkg. of 10/1.29 Meter and Box Mini Audio Amp "PC" Line Cords Harness the Sun (1) (2) (3) III (1) 1195 (2) High -Gain 6 -foot AC cords for com- Top-quality, grounded (1) (2) IC Design puters, printers, business machines. UL listed. (1) 0-15 DC Voltmeter. Mounts in 171a" (1) With Straight HP (CEE -Type) Connector. (1) Silicon Solar Cell. Produces about round hole. #270-1754 7 95 With a built-in speaker, it's the perfect #278-1257 3 99 0.3 amp at 0.55VDC. #276-124 .. 3.95 (2) Two -Piece Enclosure. Easy to test amp and also well -suited for com- for tight if desired. Accepts PC puter voice and music synthesis applica- (2) With 90° HP Connector. Ideal (2) Solar Project Kit. Includes mini so- drill or shorten, 599 board and 9V battery. 56/8 x 2'/a x 1'/,6" tions. Has volume control and '/e" input spaces. #278-1260 lar panel, motor, propeller, project book- #270-257 4 99 and earphone jacks. #277-1008 (3) Extension. #278-1259 4 99 let. #277-1201 10.95 Assortments Power Hookups Locking Plugs Infrared Buys

(1) -810 ecoge (1) With (2) Crimp 1795 Pins (1) 20 LEDs. Assortment may include Ideal for Nintendo' Design Your Own (2) Positions Type Cat. No. Each MV -5054, MV -50, RL -209 in red, Adds extra zip to popular video IR Control System green, amber, infrared. 2 Male 274-151 .99 games! Features autofire switch, 6 Male 274-152 1.69 #276-1622 1 98 12 Male 274-153 1.99 (1) IR Detector Module. Detector, amp, two separate "fire" buttons and limiter, filter and more! #276-137, 3.49 (2) 5 Photocells. CdS photoresistors. start/select control. #270-1704 2 Female 274-154 .99 Ideal for experiments. Various styles 6 Female 274-155 1.69 (2) SEP8703-1 IR LED. High power out- 12 Female 274-156 1.99 and ratings. #276-1657 1 98 *Registered trademark of Nintendo put. #276-143 1 69 Probe -Style Multitester "Pro" Soldering Station Breadboard & Jumpers 3995 (1) (2)

A super gift for any builder! Features selectable 15/25- watt power, sponge cleaner fully grounded 3995 Ideal for Testing On -the -Go and tip. UL 1995 495 listed AC. #64-2057 data -hold button freezes display and lets Iron -Clad Replacement Tips. Convenient #64-2089 Pkg. (1) Deluxe Breadboard. Molded 2'/4x6'/2" board is you remove tester for easy reading. Features autopolar- .... of 2/4.99 mounted on a 7 x 4" steel base with rubber feet. 640 indicator. Measures Tips for Soldering Surface - ity, continuity sounder, low -battery plug-in points and three binding posts. #276-169 to 400 volts AC/ DC and resistance. Ph6 x 63/e x 3/a': With Mount Devices. batteries and case. #22-165 #64-2074 .... Pkg. of 2/4.99 (2) NEW! 140 -Piece Jumper Wire Kit. #276-173 Over 1000 items in stock! Binding Posts, Books, Breadboards, Buzzers, Capacitors, Chokes, Clips, Coax, Connectors, Fuses, Hardware, ICs, Jacks, Knobs, Lamps, Multitesters, PC Boards, Radie lhaek Plugs, Rectifiers, Resistors, Switches, Tools, Transformers, Transistors, Wire, Zeners, More! The Technology Stores" Prices apply at participating Radio Shack stores and dealers A DIVISION OF TANDY CORPORATION

CIRCLE 78 ON FREE INFORMATION CARD 77 www.americanradiohistory.com DRAWING BOARD ROBERT GROSSBLATT PC photography

ALTHOUGH THE FURTHER YOU GET IN have to arrange is shown in Fig. 1. same pad you used to create the making a PC board, the less It's not as good as an enlarger, but artwork in the first place. Standard thought is involved, things don't it can work if the slide projector is component spacing is done in 0.1 - necessarily get easier. When you set up properly and the room is inch increments, making the finally do the photographic part, dark enough. The print made this graph paper a perfect negative you may be thinking less, but way will be actual size, so use template. Tape a piece of flat black you'll be working just as hard. lithographic film at least an inch paper on a wall, since you'll need a Don't forget Grossblatt's twelfth larger than the PC board in both backing for the film when you law: THINGS DON'T GET BETTER, THEY JUST dimensions. This gives you an ex- make the actual exposure. If you GET DIFFERENT; a problem is a prob- tra border to handle the negative use an enlarger, tape the black pa- lem, no matter how you look at it. and tape it to the PC board copper per to the easel. The projector side. light will go right through the film; Making the negatives without a black surface to absorb By this time you should have a it, there might be a second, spu- camera negative of the PC board --- sL/p rious, image. layout you made on graph paper. It P.eoE GTo,2 Put the graph paper on top of may be full of dust spots F M W the black paper, the original cam- ("hickies"), but they'll be taken .41 GLASS /190LINT W/Tf/ era film in the enlarger or proj- care later. EMI/LS/OA/ TOWARD of Having the camera L ENS ector, and adjust the projected film doesn't mean you can trash image size. Varying the image will the original artwork-close, but also change it's size so you'll have not quite. The next thing to be to adjust for a sharply focused im- done are the actual camera film age of correct size. You can use IC negatives; how much work that pads as a good way to check image entails depends on whether size. Since they're on 0.1 -inch cen- you're using positive or negative ters, they should line up with the L/nyoGRA/'y/G F'ILrM resist. No matter what method you /-t/./Tf/ E,4i1./L S /ON graph paper grid. Check the size at use, the first step is to enlarge the TO/y,AR.0 o,eoEGToQ points all across the image to make camera film and make a full-size sure of the enlargement. If one print of the layout. An enlarger is edge lines up but not its opposite, best, but there's another way if you the image isn't being projected don't have one. perpendicularly. If you shot the layout with 35 Exposure and development are FIG. 1 mm film, you can put the film in a done the same way as for the origi- mount and use a slide projector Exposing and processing the nal camera film, the only dif- instead of the enlarger if you're film is easy, but making the final ference being the exposure time careful. Use glass mounts to make print exactly 1:1 will take work. since you're using a different light sure the projector bulb heat Some people put dimension source and lenses. There's no ex- doesn't curl the film and distort marks on the original artwork and act time to use, but the film has the image. Put a red filter over the measure them on the projected incredible latitude; since you can projector lens so you can position image. This is a good theoretically, watch it develop, better to overex- the unexposed film. You'll also but remember Grossblatt's eighth pose than to underexpose. need some way to make sure the law: THEORY AND PRACTICE ARE ONLY THE- A 1 -minute exposure time is a unexposed film surface is perpen- ORETICALLY RELATED. good reference; the film is expen- dicular to the slide in the proj- The only way to absolutely guar- sive, so experiment on small test ector. antee actual size is to project the pieces first. Once the film is de- The enlargment setup you'll image onto graph paper from the veloped and dried, you shouldn't 78

www.americanradiohistory.com need the original artwork any longer. If you modify the layout, you RC DECADE BOX A New AOR can always make a paper print of continued from page 42 the film to make the changes. Be- Scanner sides, the adhesive on the tape increase residual resistance and ca- and pads on the original even- pacitance, and cause inductive effects 100 Channels Low, Air, tually dries out and falls off the at high frequencies. Solder resistors High, UHF & 800MHz graph paper. as close to the switch terminals as Next, clean any dust off the film possible, and the fuse holder goes using a magnifying glass and X - between BPI and the pole of S6. Pin 1 acto knife. Lay the film emulsion of S6 is soldered to the pole of S5, pin side on a piece of white paper and 1 of S5 to the pole of S4, etc., ending carefully scrape off the hickies and with pin 1 of S2 being soldered to the other contamination. Use tape pole of Si. The pole of SI is soldered and pads to add black to the film to pin 1 of S13. Perfect for base or AR950 on the base side, not the emulsi- Solder capacitors to each position AC Total Price. Freight Prepaid mobile. Includes (Express Shipping Optional on, since the next step is to con- on S7-S12, and their common leads and DC power cords, tact print the film with the emulsi- to a single lug above the switch base. mobile mount hardware and 2 antennas. $29900 on side down. Connect all common lugs together Covers 27-54MHz, If you use positive resist, you're and to pole 2 of S13. Solder all poles 108-174MHz, 406-512MHz finished with the photographic of S7-S12 together, and then to BP6. and 830-950MHz. 5 Scan Banks and 5 Search Banks part of this process, but if you use Drill the case as in Fig. 5. 25 Day Satisfaction Guarantee negative resist, you still have to No Frequencies Cut Out. Size: 31"H x 53'5"W x 77/e"D. Wt.: 2 lb. 10 oz. make a film negative. You can Checkout make PC boards reliably either Visually inspect all wiring and sol- way, but while negative resist takes dering; to complete the checkout, use an extra photographic step to an ohmmeter and capacitance meter. COMMUNICATIONS 10707 E. 106th St. Iadyls., IN 46256 make the film, it gives you another Turn S13 to position R/C, set S1-S6 to Toll Free 800-445-7717 clean it. zero, place an ohmmeter between BPI Visa and MasterCard chance to (COD slightly higher) CD All the black on the positive be- and BP2, and measure the, residual In Indiana 317-849-2570 Collect FAX (317) 849-8794 comes copper on the final board, resistance; it should be under I ohm. so scraping away emulsion is As you rotate SI, the meter should CIRCLE 182 ON FREE INFORMATION CARD equivalent to removing unwanted increment by the value of the con- DIGITAL VIDEO STABILIZER copper. When working with a nected resistors. Set SI to 0, and re- ELIMINATES ALL VIDEO COPY negative, the clear areas become peat for S2-S6. After S 1-S6 are PROTECTIONS the copper so scraping emulsion is tested, set each to 1-6, in turn. The the same as adding copper. meter should indicate the sum of each Producing the negative is done switch times its multiplier, or 1.11111 by contact printing the positive on megohm, 2.22222 megohm, etc., up While watching rental a piece of lithographic film. You to 11.1111 megohm. Repeat for the movies, you will notice an- WARNING : noying periodic color can use the projector or the en- capacitance section. darkening, color shift, un- SCO lines, larger as source SER wanted flashing or Electronics and the light with the Turn S13 to the position and jagged edges. This is same exposure times. Put the two measure the capacitance between BPI caused by the copy protec- RXII dealers do tion jamming signals em- pieces of film emulsion -to -emulsi- and BP6; you won't be able to mea- bedded in the video tape, not encourage such as Macrovision copy people to use on, and lock them in a contact sure resistance in this position. In the protection. Digital Video Stabilizer. RXII completely the Digital frame. You but PAR can also use glass, position, measure both resistance eliminates all copy protec- Video Stabilizer back the whole thing with black tions and jamming signals and capacitance between BPI and and brings you crystal clear to duplicate paper again; the PC board produc- BP6. In the LPF position, measure the pictures. FEATURES: rental movies tion setup is shown in Fig. 2. resistance between BPI and BP6, and Easy to use and a snap to Install or copyrighted the capacitance between BP6 and State-of-the-art in- video tapes. tegratedg circuit technot- Making the PC board BP4. With S13 set to HPF, measure the RXII is in- 10096 automatic - no tended to stabi- Once you've got the final print, resistance between BP1 and BP4, and need for any you're ready to deal with the cop- the capacitance between BP6 and troublesome adjust- lize and restore ments clear per PC board; it has to be sen- BPI. The decade box should now be Compatible to all types crystal of VCRs and TVs picture quality sitized, exposed, and developed, finished. The best and most exciting Video Stabilizer in for private before it can be etched. Cut your- Once you've gotten everything the market Light weight (8 ounces) home use only. self a piece of PC board at least an working, using the resistance or ca- and Compact (1x3.5x5 ) ( Dealers Welcome is Beautiful deluxe gift box inch larger in each dimension than pacitance sections straightforward. Uses a standard 9 Volt the printing negative. Before the Just set S13 to the desired position, battery which will last 1- 2 years. PC board can be sensitized, the and use the terminals indicated in Fig. copper has to be absolutely clean. 4 and Table I. The RC filters can be ToOrder: $49.95 ea + $4 for FAST UPS SHIPPING The best way to clean the copper used to either eliminate unwanted cir- 1-800-445-9285 or 516-694-1240 Visa, M/C, COD M -F: 9-6 (battery not included) is by scrubbing with soap -filled cuit noise, or perform pulse shaping SCO ELECTRONICS INC. Continued on next page and delays. R -E Dept. CR5 581 W. Merrick Rd. Valley Stream NY 11580 Unconditional 30 days Money Back Guarantee

CIRCLE 191 ON FREE INFORMATION CARD 79 www.americanradiohistory.com steel wool and hot water. You'll can speed things along with a hair leave fine scratches, but make sure dryer. This tends to get resist trap- P, OEcTO,2 they're linear, not circular; de- ped in the upper part of the liquid velopment will be easier if this is ,i -COVER TNE and makes exposure and develop- SL/DE the case. Dry the board with paper OPEN/NG ment much easier. Use about a fY/T/V A P/EOE OF towel (watch out for lint), and han- 100° F (medium setting most RED ' rFiz rE,e ) on dle it only by the edges or skin oil kEo GE- models) because the resist loses will ruin your work. -) 7-;747-E,2) photosensitivity if it's too hot. Resist comes in both spray cans CONTACT FRA41E oe Make the exposure by putting the OF GLASS and bottles. I don't use spray cans P/GE negative on the board, locked in because they have a habit of spit- the contact frame.

ting, are expensive, and have lim- PoS/T/VE F/L41 ly/TX I use an old sun lamp to expose rML17 5/ON 5/DE DOWN ited shelf life. I bought a quart the board for 7 minutes at about 2 bottle of Kodak Photo Resist (Cata- feet, but any light source between log #189-2074) about eight years o 300-400 nanometers in wave- X ago, I've made a lot of boards with F/Ly1W/THEM- length will work, like mercury it, and it's still half full. The same A s/pN S/DE UP vapor (found in most sun lamps), P7PE,e with the developer; I bought a gal - I"; i ,00 or type -BL UV fluorescent lamps. Ion of Kodak Photo Resist De- Applying the resist and making veloper (Catalog #176-3572) at the FIG. 2 the exposure are critical to making same time and still have half left. the PC board, so you can never get All of the chemicals you use have but keep the strokes short, and too much information. Kodak some level of toxicity. Work in a make sure no air bubbles or con- makes a great booklet called "Pho- well -ventilated area, and keep the tamination get trapped on the sur- tofabrication Methods with Kodak containers well sealed. face. Once covered, set it at an Photo Resists" (Catalog #P-246), Pouring the resist on the PC angle to let the excess run off. The that even has answers to questions board is simple, but more is too resist is only sensitive to a narrow you never thought of; get it. Next much. Pour a few drops on the band of UV, so you can keep a month, we'll finish off, and discuss copper and cover the surface by fairly bright light on while you're what can be done to make the slowly tilting the board from side working. PC board manufacture less of a to side. You can use a small brush, The resist dries quickly, but you hassle. R -E CABLE TV TB -3 (Tri -Bi) or SA -3 Quantity 10 20 Prices 50 100 48. $43. $39. $35 Each Each Each Each King Wholesale 1-800-729-0036 "No one beats the King's prices!" DESCRAMBLERS

www.americanradiohistory.com REFERENCE LEVEL knob; the upper ANALYZER Try the SPECTRUM setting (20 dBm or 69 dbmV) isn't continued from page 32 represented. The PSA-65A also up- Radio- dates the CRT every 5 seconds, peak again centered, the user then causing it to flash briefly. Electronics sets the VAR SPAN to CAL. The peak bulletin board should compress to its minimum Conclusion system observable width, and the user Even with the minor limitations moves the HORIZ POSITION knob to like the TUNING knob lag on the (RE-BBS) recenter the peak one final time. If LCD in NORM mode, the non - 516-293-2283 done properly, rotating the VAR linearity of the FINE TUNE knob, the SPAN control toward ZERO SPAN sho- reverting to a time -dependent dis- The more you use it the more uld expand, but result in no hori- play in the ZERO SPAN position of useful it becomes. zontal deflection. The procedure the VAR SPAN knob, and the need should become habit after a cou- for horizontal calibration, this is a We support 300 and 1200 baud ple of trys. very impressive instrument for the operation. price. It allows spectrum -analyzer Parameters: 8N1 (8 data bits, no The and CRT at a fraction of normal graticule capability parity, 1 stop bit) or 7E1 (7 data The vertical axis is calibrated in cost, and will popularize the con- bits, even parity, 1 stop bit). both dBm and dBmV; there's a 49 cept of using one as a complement dB difference between the two to an oscilloscope. AVCOM is cer- Add yourself to our user files to scales. The top horizontal line of tainly moving toward their goal of increase your access. the graticule indicates numbers in putting a low-cost spectrum ana- Communicate with other R -E both dB and dBmV, the reason lyzer on every RF technician's readers. being that the graticule was a hold- workbench. over from an earlier instrument. At $2675, the PSA-65A is a defi- Leave your comments on R -E with The numbers indicate the inter- nite bargain. Even if you think that the SYSOP. pretation associated with the top you need a spectrum ana- don't RE-BBS horizontal line, for the various lyzer, we're sure this one would 516-293-2283 three lower settings of the prove you wrong. R -E NOISE REDUCTION CABLE - TV FOR UNDER $10.

MiXit,G JACKS Con/ band -stop filters PLuGs FOR ELIMINATION OF SEVERE INTERFERENCE SWITCHES FOR"CENSORING" OF ADULT BROADCASTS BAYS PATCH

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CIRCLE 50 ON FREE INFORMATION CARD

www.americanradiohistory.com cording to the manufacturer's instruc- DIGI-COMPASS tions first. Keep the compass sensor CD PLAYERS continued from page 51 away from the compass display, com- continued from page 53 puter equipment, metal objects, etc. The "port" value shows the cur- Any magnetic fields generated by detector outputs are fed to a preamp rently used LPT port. You can switch electronic equipment or appliances, and a data strobe to differentiate be- between the available LPT ports by or nearby ferrous metals could affect tween logic -highs and logic -lows and pushing the "P" key. That is ex- the calibration accuracy of your Digi- extract sync. The data processor de- tremely handy while debugging the Compass. Also, do not use a metal modulates signal data, does error de- compass or if you have two compasses screwdriver to adjust the compass or tection/correction, and performs over- attached to your computer. your adjustments will be mean- all signal processing control. The text -only program, ingless; use the supplied non-magnet- All CD's have some provision for TEXTCOMP.EXE, must be used if your ic adjusting tool. interleaving error-correction informa- display adapter is not compatible with To run the text -based compass pro- tion into signal data when a disc is COMPASS.EXE. It too will auto -config- gram, plug the interface into the par- recorded, minimizing the effect of au- ure the LPT port and provide default allel printer port of an IBM PC/XT/ dio dropouts. The loss is distributed acquisition averages. You can include AT. On the command line type over various smaller gaps in the final the LPT port on the command line as "TEXTCOMP LPTx" (where x is a audio. "Filling in" missing informa- well as the number of acquisition aver- 1, 2, or 3, depending on the port tion on either side of a gap isn't diffi- ages to perform (up to 255). To in- used). Be sure to specify directory cult; the D/A converter follows the clude the average argument, you must paths as required. For example, sup- signal processing, and the restored include the LPT port argument. Stan- pose you plugged Digi-Compass into analog is then restored to pure two - dard syntax is: TEXTCOMP LPTn10, LPT1 and had TEXTCOMP.EXE on a flop- channel audio by a Sample -and-Hold where "n" is the printer port desired py in the A drive. At the command (S/H), and applied to the two stereo (1, 2, or 3), and "10" is the number of prompt, you would type "A:TEX- channels. averages (0-255). TCOMP LPT1." To calibrate the interface unit, ad- Proper test equipment Calibration just the "max -limit" potentiometer When servicing CD players, the en- All adjustments must be made on a (R17) to 4.15 -volts DC at pin 1 of IC3 tire laser pickup has to be replaced in flat non-metallic surface, and the and the "min limit" potentiometer the event of a failure; optics are rarely compass unit must be calibrated ac - (R18) to 1.15 -volts DC at pin 3 of IC3. adjustable, except for the drive motor, With the interface unconnected from drive belt, or gears. According to a the computer, carefully direct the recent EIA publication, the laser flux -gate sensor exactly to the North- pickup is most prone to failure due to east, keeping the sensor perfectly wear. CD test equipment is similar to horizontal. Adjust the "gain" poten- that used in standard audio. Sencore tiometer (R16) on the interface so that Electronics has many CD servicing pin 2 of IC3 is 4.25 -volts DC. products (see Table 1), but they don't Aim the sensor up to 5 degrees have a laser-power meter. While such towards the North, and then up to 5 meters are available, you can get by degrees to the East, and verify that the without one by testing the detector voltage does not exceed the adjust- diode outputs; if incorrect, the defect ments-otherwise re -adjust. When is in the laser pickup. aiming the sensor for the 5 -degree You'll need a test disc, available test, ignore all measurements beyond from some CD manufacturers, and a the 5 degrees. standard disc with prerecorded high - With the Digi-Compass interface precision test signals. Play it and note connected to the computer and the CD's response, using the indicat- TEXTCOMP.EXE running, verify that at ed instruments, if possible. The test the Northeast direction, when the X disc is used to make any CD adjust- and Y readouts match (± 2), that the ments. You can use any known good highest value is 220 ( ± 5). Adjust R17 disc and a stereo power amplifier ana- to set the highest value. Next, verify lyzer for a final check and to demon- that at the Southwest direction, when strate the player for a customer. the X and Y readouts match (± 2), Servicing CD players requires that that the lowest value is 30 (±5). If you know what the basic function of necessary, adjust R18 on the interface each section of the circuitry does. You to set the lowest value. Now go back will, of course, also need your basic and recheck those steps, as they are electronics troubleshooting skills. interactive. Verify that the compass Aside from that, all you really need is readings match the computer's read- a little mechanical know-how; just outs while in the "digital" mode. The study the mechanical operation of the Digi-Compass interface is now ad- player, and you'll probably find the justed. R -E defective part. R -E

82 CIRCLE 108 ON FREE INFORMATION CARD www.americanradiohistory.com i ER/GESi

EDITOR'S WORK- BENCH

386 Power On A 286 Budget

You want a 386, but your pocketbook says no. End of discussion? Maybe not, depending on what you want that 386 ecent advances in modem technology make it for. If it's raw speed you're after, you're out of luck. But if intel- harder than ever to pick the right modem. Here's how. ligent memory management puts a gleam in your eye, you'll find a TJ BYERS ufacturer? By understanding Canadian product called the All how modems differ, as we shall ChargeCard highly interesting. see. Briefly, the All ChargeCard is a paints an attractive pic- small module that you install be- tureISDN of communications in the Establishing the ground rules tween the 80286 microprocessor next century, but for now we'll A modem has two basic func- and your system board. The have to live within the confines of tions.. The first is to convert bin- basic product costs about $400, the Public Switched Telephone ary data into analog signals for but unless your 286 is a PGA type Network for our communications transmission over standard tele- (most non -IBM machines aren't) needs. And that means improv- phone lines, and the second is and readily accessible, you'll ing the speed and performance of convert analog signals back into need a $100 adapter kit. Figure 1 existing modem technology. binary data suitable for a com- shows the module surrounded by Fortunately, modem technol- puter. The first process is called various adapters and tools in- ogy has kept pace with increas- modulation, and the second, de- cluded with the kit. ing PC speeds. Using advanced modulation, hence the name By itself, the ACC doesn't data compression and encoding modem (MOdulation/DEModula- change operation of your system techniques, in only a few years tion). one iota. But with the accom- modem communications has To ensure that modems from panying software, the ACC lets gone from 300 bits per second different manufacturers can you pull 386 -like tricks on your (bps) to 9600 bps-with some communicate, standards for en- 286. Such as? modems having data throughput coding, transmission, and de- Increase DOS size to 736K (in exceeding 30,000 bps. coding have been established, color systems not running Unfortunately, the lack of a sin- first by AT&T and more recently graphics programs, or 704K in gle high-speed modem standard by the CCITT (Cooperative Com- mono systems). makes it impossible to pick just mittee for International Tele- Speed up system operation by any modem from your dealer's phone and Telegraph). ROM "shadowing" (running the shelf and expect it to talk to any- At speeds as high as 2400 bps, BIOSes from RAM, rather than body else's modem. Many models the protocols are well defined and ROM, which is slower). use proprietary transmission universally accepted, and vir- Use memory above 640K for modes that can only talk to mod- tually all modems within this DOS's FILES, BUFFERS, and ems of their own kind. class can communicate with one LASTDRIVE storage areas. So how do you know if one another. It's beyond 2400 bps Use memory above 640K to modem can talk to anther that problems begin. load device drivers-including modem from a different man- continued on page 86 RAM -hungry network drivers.

83 www.americanradiohistory.com controller, as with some compatibles. The module protrudes high enough above the system board to interfere with expansion cards, but by inserting my 2/3 - length Paradise VGA card in the matching expansion slot, I didn't have to sacrifice any slots. Prying the CPU out of its socket was quite difficult, even with the special tool supplied by the company. (The heatsink visible in the pho- tos was supplied by me simply because I happened to have it, not because the company recom- mends it.) After installing the card, youll FIG. 7 want to set up any non -DOS memory in your system as ex- Use memory above 640K to [Installation tended memory (that normally load TSR's: SideKick, DOS's Installation can be difficult, de- addressed linearly above the 1MB MODE program, Smart Key-you pending on the physical config- mark) to let the ACC do its tricks. name it. uration of your system. If the You may have a problem if your Convert some or all extended microprocessor is soldered to the system board forces you to allo- memory into fully register -com- system board, you're simply out cate 384K of memory as extended patible EMS 4.0 memory, which of luck. Best is a PGA type, which memory. is great for running OMNIVIEW is used in IBM AT's and a few After completing the physical and Windows. other compatibles. (All Comput- installation, you can boot your Add EMS 4.0 page frames ers has a list of machines and PC and run as normal. However, above 640K to let Windows run corresponding CPU socket to reap the benefits of the ACC, more efficiently. types.) The PGA type has rigid you must install a device driver in The disadvantages? Cost is pins that allow you to insert the your CONFIG.SYS file. Depend- one. At $500, the ACC is just a IC into machined socket pins. ing on the options you specify few hundred dollars cheaper Most machines, however, use there, you can backfill memory to than the least expensive 386SX LCC or PLCC types, which re- the 640K mark or higher, specify system boards that are currently quire the adapter kit. the amount of memory to allocate on the market. And even with the In my test system (an AST Pre- as EMS and as extended, enable ACC, a 286 -based system will mium/286 with a PLCC socket), ROM shadowing, etc. To max- never be able to run 32 -bit soft- installation was fairly easy. My imize contiguous DOS memory ware, nor will it be able to take CPU socket is located near the left you should remove the FILES, advantage of full 32 -bit address edge of the system board, not un- BUFFERS, and DEVICE state- and data buses. der the hard disk drive or disk ments from your CONFIG.SYS and run All's corresponding pro- ,, t .t.+e..s...... s.,,aw.,..e.....,xt...t.eN. c.k.. grams from AUTOEXEC.BAT. .0 ...... w...... , ..te..a...t..w.,.e..t e...e.,t ...... The real world I found the All ChargeCard a pleasure to use. With it, I ran 0M- NWIEW (a multi -tasking environment) and was able to download files (using ProComm Plus) from an on-line information service at the same time as I wrote this review In addition, the card increased my DOS memory space by about 25K, and if I gave up the ability to run graphics programs, by about 120K. The ACC may seem kind of "kludgy" but it's been through several design iterations (early versions required you to modify your application programs), and FIG. 2 most of the kinks have been

84 www.americanradiohistory.com Rates: Ads are 21/4" x 27/4". One insertion $900. Six insertions$875.each.Twelve insertions $845. each. Closing date same as regular rate card. Send order with remittance to Computer Admart, Radio Electronics Magazine, 500-B Bi -County R -E Computer Admart Blvd., Farmingdale, NY 11735. Direct telephone inquiries to Arline Fishman, area code -516-293-3000. Only 100% Computer ads are accepted for this Admart.'

DELIVERY!!! SAME DAY SHIPPING (USUALLY) SECRETS OF THE A PRACTICAL ICSICsPROMPTQUANTITY ONE PRICES SHOWN for AUG. 20, fRBS TO OUTSIDE OKLAHOMA NU SALES TAX COMMODORE 64 INTRODUCTION DYNAMIC RAM SIMM 1f1 256Kx36 80 ns $400.00 Secrets of the MICROPROCESSORS SIMM 1Mx9 70 ns 190.00 cefp M1,EO COMMODORE 64 (2) 1Mx9 80 ns 150.00 SIMM Axli> 81123 -Introduces mi- A Practical SIMM 256Kx9 80 ns 70.00 Introduction to BP135-A beginners guide 1Mbit 1Mx1 100 ns 12.90 croprocessors by having Microprocessors to the Commodore 64 pre- 41256 256Kx1 60 ns 7.25 the reader construct a 6.25 sents masses of useful data 41256 256Kx1 80 ns very simple micro- 41256 256Kx1 100 ns 4.15 and programming tips, as processor circuit that he 41256 256Kx1 120 ns 3.50 Mau t 4464 64Kx4 120 ns 5.00 well as describing how to can experiment with and 101 ns 11.95 get the best from the 41264 64Kx4 120 )f thus hopefully gain a EPROM mS powerful sound and graph- clear insight into this 27C1000 128Kx8 200 ns $22.00 ics facilities. We look at how the memory is 27512 641(x8 200 ns 9.50 complex subject. The 27256 32Kx8 150 ns 7.25 g organized, random numbers and ways of completed unit is only 27128 16Kx8 250 ns 4.50 mÑ generating them, graphics -color-and sim- aid, but can be STATIC RAM intended as an education 62256P -to 32Kx8 100 ns $20.95 ñ8 a ma- ple animation, and even chapter on and many of the parts 6264P-12 8Kx8 120 ns 5.95 built inexpensively m Ñ chine code. Get your copy today. Send can be reused for other applications later. 6116AP-12 2Kx8 120 ns 4.50 $5.00 plus $1.25 for shipping in the U.S. Get your copy for $5.00 plus $1.25 for OPEN DAYS. 73040 lOPN SHIP VIA FED -ES ON SAT. SAT DELIVERY MasterCa,d. VISA o, UPS CASH COD to Electronic Techology Today Inc., P.O. shipping in the U.S. from Electronic Tech- INCLUDED ON MICROPROCESSORS UNLIMITED, INC. FEO -E2 ORDERS 24 ODO S FoVeA A Box 240, Massapequa Park, NY nology Today Inc., P.O. Box 240, Massape- RECEIVED BY: NEGUS OK 74d21e (918) 267-4961

f1,1 M3 No minimum order. ^r . 11762-0240. qua Park, NY 11762-0240. ,: F MSS , CIRCLE 61 ON FREE INFORMATION CARD worked out. Even so, there are software that takes direct control camel manure or You bungling still a few. For example, you can't of the DMA hardware, it won't be tub of soppy buzzard barf or .. . reset your machine by pressing a problem for you. well, you get the idea. If you ad- Ctrl -Alt -Del or even a hard' reset All in all, then, the All mire such crafty use of language, switch; instead, you must run a ChargeCard is quite an intrigu- but find it difficult to create such small program that clears the ing device. At half the price, it gems yourself, get a copy of In- ACC's registers and then per- would be a steal. However, at the sults2, a public domain -pro- forms the normal DOS reset se- $500 level, it's just under 386SX gram. It's available from the quence (i.e., JMP FFFF:0000). system board and accelerator author directly for $5, or free The problem is that you don't al- card prices (which will undoubt- from many BBSes, including ways have access to the DOS edly continue to fall), so choosing RE's (516-293-2283, 300/1200 command line when you want to between the two is difficult. If bps, 8/N/1). The author also sells reset your machine (for example, compatibility with future 386 a related product, called Pranks, if a program has hung your sys- software is important to you, for $20. Pranks is a collection of tem). In that case, your only re- you'd be better off avoiding the programs you can run on an un- course is to power down and back ACC. But if you want to upgrade suspecting user's PC to make up. now at the lowest possible cost, him think there is something se- A somewhat more serious the All ChargeCard won't disap- riously wrong with it. Pranks is problem is that the ACC doesn't point you.e $ neither public domain nor share- handle DMA operations properly. ware, and it must be ordered di- To increase transfer speed, tape rectly from the author..CD« backup units often grab direct control of the DMA hardware. That can be a problem with the All software running, because ITEMS DISCUSSED physical and logical memory no Insults2 ($5), Pranks ($20). longer correspond to one an- Modern Advisory Institute, P.O. other. The company supplies a Box 11632. Salt Lake City. UT program that is supposed to solve 84147. (801) 569-0730. the problem, but it left my ma- CIRCLE 48 ON FREE INFORMATION CARD chine with only 372K of DOS Insults A La Carte memory, which was not enough All ChargeCard ($399), to run my Irwin 785 tape drive. Adapter kit ($100). All Comput- My only recourse is to remove the reating insults is an all -but - ers Inc., 1220 Yonge Street, Sec- All EMS driver from CON- lost art. Anyone can string ond Floor, Toronto, Ontario, FIG.SYS, reboot, run the backup together a bunch of four-letter ex- Canada M4T 1W1. (416) software, restore the driver, and pletives, but that's not what I'm 960-0111. reboot again. And that's a real talking about. Rather, things CIRCLE 47 ON FREE INFORMATION CARD pain. Of course, if you don't use like: You boring mound of septic 85

www.americanradiohistory.com rapid, scheduled succession. MODERN MODEMS MODEM SOUP The disadvantage is that valu- Modem jargon continued from page 83 is replete with ac- able time is wasted if one modem ronyms, coined words, and has nothing to send. One problem is simply the mysterious V.xx codes. Here is a Hayes is the most popular 2700 -Hz bandwidth of the tele- list of the most common modem manufacturer using ping-pong phone line. Another is the incom- terms and their meanings. The duplexing (which they have la- definitions patible compression methods are grouped by cate- beled V.32 HDX) with its V -series modem manufacturers use to gory. Smartmodem 9600. However, at TRANSMISSION MODES maximize throughput. Low - 9600 bps, the Hayes modem can speed modems have the advan- V.32 9600 bps, full -duplex, trel- talk only to another Hayes lis tage because their 2400 -Hz encoding w/echo cancella- modem-not even a 9600 bps bandwidth easily fits into the tion modem from another manufac- voice band. To move the data fast- V.32 HDX 9600 bps, ping-pong turer that uses the ping-pong er, however, we must increase the duplex, QAM encoding, used by method. (The Smartmodem coding density of the carrier by Hayes 9600 is compatible with stan- using more complex coding V.29 9600 bps, half -duplex, dard modems at lower speeds, methods (see sidebar). QAM encoding, for use with however.) Unfortunately, the transmitted dial -up fax Statistical duplexing uses a waveform gets more intricate as V.27 4800 bps, half -duplex, high-speed V.29 data channel coding density increases, and DPSK encoding and a low-speed reverse channel the hardware needed to differen- V.22 2400 bps, full -duplex, to keep the two modems in tiate between signal changes and QAM encoding touch. The reverse channel is a line noise grows more complex V.22 1200 bps, full -duplex, full -duplex service channel that and expensive. The solution is to DPSK encoding operates at about 300 bps and is change transmission method so V.21 300 bps, full -duplex, FSK used to let each of the modems the waveform is simpler. How- encoding know the status of the other. ever, it's nearly impossible to get Bell 208 4800 bps, half-duplex, Based on their communication two modem makers to agree on a DPSK encoding needs, the high-speed data chan- common transmission mode and Bell 212 1200 bps, full -duplex, nel is assigned to one or the data -encoding method. DPSK encoding other. That arrangement is akin Bell 103 300 bps, full -duplex, to one person in a conversation Competing techniques FSK encoding doing most of the talking-like a The first attempts at creating a ENCODING/DECODING teacher who is occasionally inter- high-speed modem saw modem Trellis Modified Quadrature rupted by a student asking ques- Amplitude makers modifying cheap 9600 - Modulation tions. Data buffering prevents bps modems already in common QAM Quadrature Amplitude loss of data when the data chan- use by fax machines. Those mod- Modulation nel isn't immediately available. ems, which use the CCITT V29 DPSK Differential Phase -Shift Statistical duplexing makes transmission mode, provide one- Keyed modulation better use of the link, but the way (half-duplex) data transmis- FSK Frequency -Shift Keyed data still only travels in one direc- sion over normal phone lines. modulation tion at a time. The current record But for two modems to talk to DATA COMPRESSION holder for statistical data each other and carry on a two- V.42 Pending CCITT standard, throughput is U.S. Robotics' sided conversation, they must compliant with MNP 2-4 error Courier HST, with a claimed data have a full -duplex link. Two correction only rate of 14,400 bps. methods are commonly used to MNP 9 Includes all the features make the V.29 modem behave of MNP 7 plus V32 operation Echo cancellation like a full -duplex modem: ping- MNP 7 Includes all the features The fastest and most popular pong duplexing and statistical of MNP 5 plus look -ahead fre- high-speed transmission meth- duplexing. quent -character recognition od is CCITT's V.32 full -duplex MNP In ping-pong duplexing the 5 Provides sequential and protocol. A V.32 modem can send two modems take turns talking, frequent character data com- and receive data simultaneously like two persons carrying on a pression because it places both con- normal conversation. The first ERROR CORRECTION versations on the line at the same modem begins by turning its V.42 CCITT standard, com- time and uses echo cancellation transmitter on and sending data. pliant with MNP 2-4 to sort them out. After a prescribed amount of MNP 4 Includes all the features Although the two signals clash time, control of the phone line is of MNP 3 plus automatic varia- and interfere with each other, the given to the other modem, which ble data packet sizing method works because each now transmits data until its turn MNP 3 Synchronous framing modem knows what it is send- expires. The process continues using CRC ing. It's like the way we are able to with the two modems swapping MNP 2 Asynchronous framing carry on a conversation at a noisy packets of data back and forth in using parity bit checking cocktail party by tuning out ev- 86 www.americanradiohistory.com HOW MODEMS TALK OVER PHONE LINES Sending digital data over analog PHASE COPED phones lines may seem compli- CARRIER cated, but it's not really. The U l v v Ji v technology is based on a modulated audio -frequency carrier PHASE (like the RF carrier used by ra- CHANGE dio and TV) that fits within the BINARY 0 confines of the phone network's VAWE voice band. The trick is encoding the carrier for reliable communications over the wide +1 range of changing line conditions that are usually experienced on the dial -up telephone network. Although early modems used frequency -shifted keyed (FSK) 1-1 modulation to get the message across, modern modems rely on phase -shift encoding. The simplest phase -shift en- FIG. 1-PHASE-SHIFT KEYED MODULATION is a popular coding scheme, called differen- technique in older (less than 1200 bps) modems. tial phase -shifted keying (DPSK), has two oscillators run- a value somewhere between by doing so, the telephone's ning 90 degrees apart. Accord- zero and unity, we can achieve voice band can accommodate ing to the value of the binary bit, greater coding density. This only one carrier. the encoder chooses between scheme is called quadrature An example of this transmis- one of the two oscillators at pre- amplitude modulation (QAM) sion mode is V.29, the CCITT determined intervals to produce and is the secret behind suc- standard that is used by fax ma- a waveform similar to that cessful high-speed modem data chines around the world. It uses shown in Fig. 1. encoding. a 2400 -Hz carrier to provide The direction of the phase The first of the popular mod- faithful communications at shift itself doesn't determine ems to use QAM was the V.22 9600 bps, but provides only the value of the data bit. In- modem-the same 2400 -bps half-duplex operation. stead, the bit value is deter- modem that is sold by Hayes The V.32 modulation tech- mined by the algebraic sum of and just about everybody else. nique is very similar to V.29 ex- the vector components. The two In V.22, the vectors are scaled cept that it provides full -duplex oscillators are 90 degrees apart, so that there are 16 vectors operation at 2400 Hz by using so that gives us four vector pos- rather than four, which means echo cancellation. Moreover, as sibilities ( + 1, + 1; + 1, - 1; the quadratures can now repre- a bonus of the complex data pro- -1,-1,; -1,+1), as shown in sent four bits of data instead of cessing required to make echo Fig. 1. Consequently, if we want two. When this encoding cancellation work, V.32 is able to encode al onto the carrier, we scheme is used on a 1200 -Hz to offer 32 -point QAM encoding. must shift the phase difference carrier, it means the carrier can Instead of the expected eight so that the algebraic sum lands be modulated at 600 baud and bits of data, however, the eight in quadratures + 1, + 1 or still leave us enough room for vectors are trellis -encoded to -1, -1. Phase shifts that place two carriers, one at 1200 Hz and provide five bits of data. Pres- the vector in quadratures one at 2400 Hz, for full duplex ently, the fifth bit is used to pro- + 1, -1 or -1, +1 cancel to zero. operation at 2400 bps. vide information for the pur- Encoding is done using an ex- However, 16 -point QAM is the poses of error correction, which clusive NOR gate, and the signal limit for normal dial -up phone means that the data is decoded using a phase -locked communications. Beyond that, throughput of V.32 32 -point loop (PLL). Both the Bell 212A the line noise overwhelms the vector is the same as it is with a and V.22 1200 -bps modems use smaller discrete signal changes 16 -point vector. But now that DPSK encoding. unless complex-and expen- 32 -point QAM encoding is out With DPSK encoding, the vec- sive-decoding hardware is of the bag, it may signal the be- tor sum is scaled to unity (+ 1). used at the receiver. The eco- ginning of yet another round of However, if we scale the quad- nomical answer to faster com- modem rate increases. We're rature components to fractions munications rates is to increase certainly looking forward to so that the vector sum assumes the frequency of the carrier. But seeing that!

87 www.americanradiohistory.com erything but what we want to modem exceeded $2000. But control characters. The com- hear. By creating inverted signals more and more manufacturers pressed data is then sent over the of its output and feeding them are building V.32 modems, and phone line. At the other end, the back into the receiver, the prices are dropping below $1000. control characters are expanded modem can sort out the mess Unlike the ping-pong and statis- back into their original se- through voltage cancellation. tical protocols discussed above, a quence. When the transmitter's output V.32 modem can talk to any other However, data compression is goes positive, the receiver's refer- V.32 modem, provided both use based on a software algorithm, ence voltage goes negative, re- echo cancellation. and }finless you use the same al- sulting in a zero voltage at the gorithm both to compress the input of the receiver for that sig- Data compression data and to expand it, you'll end nal. Once the local signal has A ploy frequently used to in- up with gibberish. Although sev- been canceled, what remains is crease data throughput without eral modem manufacturers offer the signal from the other modem. inventing a new modem protocol data compression, about half of It's sounds simple in theory, is data compression. Data com- them use a proprietary algorithm but actually it's difficult to imple- pression doesn't change the way that is compatible with machines ment because of defects in the your modem works, only the way made only by them. phone network. Voltage reflec- the data is packaged before it is Only the MNP Class 5 data tions from phone connectors, sent. For example, if you had a compression method created by switching relays, and the receiv- data compressor with a 4 -to -1 Microcom has garnered much ing modem itself cast echoes compression ratio, you could popular support among modem onto the line that confuse the re- achieve an effective throughput manufacturers. MNP Class 5 ceiver. V.32 uses complex digital of 9600 bps using a standard works by identifying runs of signal processors (DSP's) to lo- 2400 bps modem. identical characters, such as cate and remove those echoes, Data compressors shrink data spaces or tabs in a table, and but at the expense of added hard- by looking for repeated charac- sending them as a shorter se- ware. ters or patterns in the data string quence. MNP data compression Until recently, the cost of a V.32 and replacing them with unique also counts the number of times a character appears in a docu- TEACHING OLD MODEMS A of normal. If the responding ment, like the letter "e", and re- NEW TRICK modem doesn't have MNP pro- names those that are frequently If you'd like to take advantage of tocol, MTE defaults to the high- used with a code that's shorter the new MNP error correction est common standard data rate. than its ASCII equivalent. and data compression tech- The MTE communications Microcom's newest data com- nology, but wince at the thought program is versatile, yet simple pression algorithm, MNP Class 7, of having to buy a new modem to use because of a user inter- includes all the features of MNP to get it, you'll be happy to hear face that supports both hot keys Class 5, plus it takes advantage about MagicSoft's MTE commu- and Lotus -style menus. MTE of predictable character se- nications software. also supports a wide variety of quences (such as the fact that u MTE allows you to add MNP 4 link protocols, including two usually follows q in English) and error correction plus MNP 5 versions of XMODEM and three replaces them with a single con- data compression to your exist- versions of YMODEM. Other trol character. ing modem without making any features include a log that rec- Average speed increases for changes to its hardware. More- ords the length of the phone call MNP data compression are twice over, MTE isn't just a device and macros for automatic logon the normal data rate for Class 5 driver that you attach to your to on-line services (Com- and up to three times the normal existing communications pro- puServe, etc.). data rate for MNP Class 7. In fact, Microcom's 9600 -bps QX/V.32c gram, but a complete communi- Perhaps best of all is the Mini - cations package. Host feature that allows the pro- modem can throughput data at MNP operation is automatic- gram to function as a simple speeds in excess of 33,000 bps and V.42 compatible. The pro- bulletin board or as a sophisti- when using MNP Class 7 data gram queries the responding cated unattended modem. Any- compression. modem for MNP compatibility, one who calls while your system then configures itself to the is in the Mini -Host mode will be Error correction highest common MNP level. The able to use your MTE program At any speed, modem trans- MNP link can be made between to do a variety of tasks, includ- missions are prone to error sim- any modem that has MNP built ing uploading and downloading ply because of the noisy phone into it, or one that uses software files from the program's SEND environment in which they must to implement MNP (like mod- and RECV directories. work. But as the speed of the ems from Zoom Telephonics). So if you'd like to give your modem increases, so does the error rate. Several methods are Once the link is established, present 2400 -bps modem 4800 - communications proceed at bps performance, MTE may be available for error detection and data rates up to two times that just the ticket. correction. The simplest appends a ninth

88 www.americanradiohistory.com bit, called a parity bit, to the data redundancy checking (CRC). In byte. The value of the parity bit is this method, a string of bytes is determined by the number of is grouped together in a packet and in the data byte. If the count is then processed by an algorithm even, the parity bit is one; if the that produces a sum represen- count is odd, the parity bit is tative of the group. This CRC zero. At the receiving end, the number is then sent along with number of is in the data byte are the group. At the receiver, the re- counted again and compared to ceived data packet is processed the value of the parity bit. If the by the same algorithm and the two don't agree, a data error is results compared to the CRC val- declared and the byte is sent ue. As before, a difference be- again. tween the two values prompts a A faster method is to use cyclic retransmission of the data packet. Obviously, CRC error checking THE RACAL-VADIC 9632VP modem PRODUCT INFORMATION is more efficient than parity -bit has CCITT V.32/V.22 and Bell 212/103 MTE ($79) compatibility with MNP through Class error checking because you don't 5 for 19,200 bps performance. MagicSoft. Inc. have to process each byte individ- P.O. Box 396 ually. However, you still have to Lombard, IL 60148 send new data to replace defec- nicate with both 300 -bps and (312) 953-2374 tive data. A high error rate sig- 1200 -bps modems, and even- MODEM MANUFACTURERS nificantly reduces the efficiency tually 2400 -bps modems. Instead Cermetek Microelectronics of CRC error checking. of having to buy a separate 1308 Borregas Ave. The newest modulation tech- modem for each speed, you Sunnyvale, CA 94088 nique, V.32, offers an optional needed only one. (408) 752-5000 fifth bit (trellis encoded). The val- That same -one -does -it -all con- Concord Data Systems ue of the fifth bit is a logical deriv- cept is even stronger today.. Al- 45 Bartlett St. ative of the other four and though you can find stand-alone Marlborough, MA 01752 represents a checksum that is 9600 -bps modems, you're more (617) 460-0808 similar to a parity bit of a byte. likely to find modems that sup- General DataComm, Inc. This extra bit gives the receiving port all popular speeds under Straits Thrnpike modem the opportunity to use er- 9600 bps. Middlebury, CT 06762 ror correcting-not error detect- However, you'll notice that the (203) 574-1118 ing-techniques to recover the operative word here is "popular." Hayes Microcomputer Prod- original data from the flawed sig- As mentioned earlier, not all ucts, Inc. nal with a considerable savings 9600 -bps modems are compati- P.O. 105203 in time because retransmission ble, and you have to pay as much Atlanta. GA 30348 is unnecessary. attention to five -speed modem (404) 449-8791 As with data compression, ev- standards as you do stand-alone Microcom, Inc. erybody has an opinion on the high-speed modem standards. 500 River Ridge Rd. best method for error detection Norwood, MA 02062 and correction. And unless the Something for everybody (617) 551-1000 method used is supported by Whether or not you're in the Multi -Tech Systems, Inc. both modems, it won't work. The market for a high-speed modem, 2205 Woodale Dr. most popular methods are MNP you'll find many of the features Mounds View MN 55112 Classes 2 through 4 from Micro- pioneered by this market trick- (612) 785-3500 com. Recently, however, CCITT ling down into the next genera- Racal-Vadic has approved its V.42 error detection of low -speed modeems. 1525 McCarthy Blvd. tion (with data packet re- At the top of the list will be er- Milpitas, CA 95035 transmission on error) standard ror correction and data compres- (408) 432-8008 that includes compatibility with sion. For example, if you choose a Telebit Corp MNP Classes 2-4. 2400 -bps modem that offers 1345 Shorebird Way MNP Class 5 data compression, Mountain View, CA 94043 Shifting gears you'll be able to talk to compara- (415) 969-3800 Time was when each modem bly -equipped 2400 -bps and U.S. Robotics, Inc. had a niche in life. If you were a 9600 -bps modems at data rates 8100 North McCormick Blvd. 1200 -bps modem, you communi- up to 4800 bps. Skokie, IL 60076 cated at 1200 bps exclusively; Yes, choosing a modem today (312) 982-5001 4800 -bps modems could only isn't nearly as simple as it was Ven -Tel, Inc. talk with another 4800 -bps just a year ago. But then again, 2121 Zanker Rd. modem. you're getting a lot more for your San Jose, CA 95131 Then Hayes came out with its money so no one's complaining (408) 436-7400 Smartmodem that could commu- too loudly.i)CD« 89

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FOR SALE JERROLD 450 module works good, information $2, COMMUNICATIONS radio, electronic equip- module $55, COD only. BILL, 7014 East Golflinks ment, sales, service, FCC licensed, free catalog, PHOTOFACT folders, under #1400 $4.00. Others #124, Tucson, AZ 85730. RAYS, PO Box 14862, Fort Worth. TX 76117-0862. $6.00. Postpaid. LOEB, 414 Chestnut Lane, East Meadow, NY 11554. GREAT buys! Surplus prices, ICs, linears, transfor- CLASSIFIED AD ORDER FORM mers, PS, stepping motors, vacuum pump, pho- totransistor, meters, LSASE, FERTIK'S, 5400 Ella, To run your own classified ad, put one word on each of the lines below and send this form along with your check to: Phila., PA 19120. Radio-Electronics Classified Ads, 500-B Bi -County Boulevard, Farmingdale, NY 11735

PLEASE INDICATE in which category of classified advertising you wish your ad to appear. For CABLE -TV AT ITS BEST special headings, there is a surcharge of $25.00. ( ) Plans/Kits ( ) Business Opportunities ( ) For Sale SCIENTIFIC ATLANTA: Education/Instruction ( ) Wanted ( ) Satellite Television

Models 8500-8550-8580. . $275.00 ) SA -3 [Add -On Descrambleri $ 99.00 zyI- JERROLD: Special Category: $25.00 o_ SB -3 [Inband Gated Sync] $ 74.00 sg TRI -BI ]Trimode/Bistate $ 95.00 PLEASE Sñ OAK: PRINT EACH WORD SEPARATELY, IN BLOCK LETTERS. (No refunds or credits for typesetting v M-356 [Combo W/Vari-sync] $ 99.00 errors can be made unless you clearly print or type your N-12 [Add -On W/Vari-sync] $ 89.00 copy.) Rates indicated are for standard style classified ads áz only. See below for additional tu HAMLIN: charges for special ads. Minimum: 15 words. o MLD-1200 [Add -On] $ 89.00 ZENITH: [Z -TAC Descrambler] .$169.00 CONVERTERS: [80-Channels] .$ 95.00 1 2 3 4 5 N.A.S. INTERNATIONAL (800) 728-4.NAS 6 7 8 9 10 PRIVACY problem - need information? New electronic debugging, surveillance, protection catalog $5.00 kits -assembled. TECHNOLOGY SER- - 11 12 13 14 15 VICES, 829B Ginette, Gretna, LA 70056. ($46.50)

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IF YOU USE A BOX NUMBER YOU MUST INCLUDE YOUR PERMANENT ADDRESS AND PHONE NUMBER FOR OUR FILES. ADS SUBMITTED WITHOUT THIS INFORMATION WILL NOT BE ACCEPTED. r THE ULTIMATE' CLASSIFIED COMMERCIAL RATE: (for firms or individuals offering commercial products or services) $3.10 per word prepaid (no charge for zip code)...MINIMUM 15 WORDS. 5% discount for same ad in 6 issues; 10% discount for same ad in 12 issues within one year; if prepaid. NON-COMMERCIAL RATE: (for ELECTRONICS CATALOG. individuals who want to buy or sell a personal item) $2.50 per word, prepaid.... no minimum. ONLY FIRST Order your 260 page catalogue packed with over 10.000 WORD AND NAME set in bold caps at no extra charge. Additional bold face (not available as all caps) 55C money saving electronic parts and equipment. Send $3.00 per word additional. Entire ad in boldface, $3.70 per word. TINT check or money order, or call 1-800-543-3568 today and SCREEN BEHIND ENTIRE AD: $3.85 per use your Mastercard or Visa. word. TINT SCREEN BEHIND ENTIRE AD PLUS ALL BOLD FACE AD: $4.50 per word. EXPANDED Consolidated Electronics, Incorporated TYPE AD: $4.70 per word prepaid. Entire ad in boldface, $5.60 per word. TINT SCREEN BEHIND ENTIRE 705 Watervliet Ave., Dayton, Ohio 45420-2599 EXPANDED TYPE AD: $5.90 per word. TINT SCREEN BEHIND ENTIRE EXPANDED TYPE AD PLUS ALL BOLD FACE AD: $6.80 per word. DISPLAY ADS: 1" x 21/4'-$385.00; 2" x 21/4"-$770.00; 3" x 21/4'-$1155.00. NAME General Information: Frequency rates and prepayment discounts are available. ALL COPY SUBJECT TO PUBLISHERS APPROVAL. ADVERTISEMENTS USING P.O. BOX ADDRESS WILL ADDRESS NOT BE ACCEPTED UNTIL ADVERTISER SUPPLIES PUBLISHER WITH PERMANENT ADDRESS AND PHONE NUMBER. Copy to be in our hands on the 10th of the third month preceding the date of the CITY issue. (i.e., Aug. issue copy must be received by May 10th). When normal closing date falls on Saturday, STATE ZIP Sunday or Holiday, issue closes on preceding working day. Send for the classified brochure. Circle Number 49 on the Free Information Card. CIRCLE 70 ON FREE INFORMATION CARD 90

www.americanradiohistory.com FREE CATALOG FAMOUS "FIRESTIK" BRAND CB ANTENNAS CABLE -TV AND ACCESSORIES. DUALITY PRODUCTS FOR THE SERIOUS CB'er. SINCE 1962 FIRESTIK ANTENNA COMPANY 2614 EAST ADAMS PHOENIX, ARIZONA 85034

WANT a CD? But no amplifier input! Unique selec- tors give the input capability you need for any audio accessory. Write today for details. JEL, 409 Angus Blvd. 2B, Warner Robins, GA 31088. 2 -WAY radio system. Used VHF base stations, portable radios, UHF car radios + many extras. (202) 9442802 for information. VIDEOBEAMER links VCR to TV without wires $99.00. MVS ANTENNAS, 1205 Coplon Ave., Schenectady, NY 12309. BONANZA! CCTV video cameras: color Sanyo VCC3700 1 10 OR $395.00, Panasonic B&W $219.00, others. PC vid- ITEM UNIT MORE eo digitizer $249.00. SAMPSON ENGINEERING, HAMLIN MCC 300036 CORDED REMOTE CONVERT ER.r .n 2900 1800 PO Box 550363, Dallas, TX 75355-0363. (214) PANASONIC WIRELESS CONVERTER lour hest huyl 9800 7900 328-2730. STAR GATE 2000 88 00 69 00 'JERROLD 400 COMBO 169 00 11900 JERROLD 400 HAND REMOTE CONTROL 29 00 18 00 'JERROLD 450 COMBO 199 00 139 00 CB RADIO OWNERS! 'JERROLD 450 HAND REMOTE CONTROL 2900 18 00 JERROLD SB -ADD-ON 9900 6300 We specialize in a wide variety of technical information, parts and 'JERROLD SB -ADO -ON WITH TRIMODE 10900 7500 services for CB radios. 10 -Meter and FM conversion kits, repair "M-35 B COMBO UNIT ICh 3 output only, 99 00 70 00 books, plans, high-performance accessories. Thousands of 'M-35 B COMBO UNIJ WITH VARISYNC 109 00 75 00 9900 6200 satisfied customer since 1976! Catalog $2. 'MINICODE IN -121 "MINICODE IN -121 WITH VARISYNC 10900 6500 CBC INTERNATIONAL 'MINICODE VARISYNC WITH AUTO ON-OFF 140 00 105 00 P.O. BOX 31500RE, PHOENIX, AZ 85046 ECONOCODE Im,n,code suhstn uII', 6900 4200 ECONOCODE WITH VARISYNC 7900 1600 'MLD-1200-31Ch 3 outpuh 9900 6200 TJ Services is here to serve you! Our quality prod- "MLD-1200-2 ICh 2 output, 9900 6200 ucts, quick courteous service, knowledgeable sales 'ZENITH SSAVI CABLE READY 175 00 125 00 people and rock bottom prices prove it! Not sure INTERFERENCE FILTERS ,Ch 3 only, 24 00 1400 what need? (313) 726-0900 we'll help! you Call 'EAGLE PD -3 DESCRAMBLER ICh 3 o,tp,t 9mly, 11900 65 00 Prices are 20/10/5/1 lot. Jerrold DRX-3-DIC quoted 'SCIENTIFIC ATLANTA ADD-ON REPLACEMENT DESCRAMEL ER 119 00 8500 $69/$79/$89/$99, DSX-3-DIC $59 each, DRX-3- 'CALL FOR AVAILABILITY auto Tri -Bi -10 $109/$119/$129/$139, DRZ-3 $49/$59/$69/$79, SB $45 each. Tri -Bi -2 or 3 $69/$79/$89/$109. Oak M35B $20 each, new origi- Output Price TOTAL nal N-12 $65 each. Scientific Atlanta type SA -3 Quantity Item Channel Each PRICE $69/$79/$89/$109, Hamlin CRX-6600-3M $89/$109/$129/$149, MLD-1200-2 or 3 $29/$39/$49/$59, CRX-6600-2 $39/$49/$59/$69, Eagle PD -3 original $59/$64/$99/$109, Inter- ferance Filters, we stock all channels $12/$15/$18/$29, Zenith SSAVI-1 Anti -flashing $89/$99/$109/$129. Pioneer type PI -3 $79/$89/$109/$129. Replacement remotes and SUBTOTAL many accessories in stock. New volume control California Penal Code #593-D forbids us from shipping any cable descrambling unit Shipping Add 78 channel wireless remote converter with parental per unit control and fine tuning capabilities to anyone residing in the state of California. $3.00 COD & Credit $79/$89/$99/$109. B.E.L. radar detector 861 close Prices subject to change without notice. out $89 each. Cards - Add 5% DI CAC= oo14IT TOTAL LASER Listener II, other projects. Surveillance, descrambling, false identification, information. Name Plans, kits, other strange stuff. Informational package $3.00 refundable. DIRIJO/BOND ELEC- Address City TRONICS, Box 212, Lowell, NC 28098. State Zip Phone Number ( D Cashier's Check Money Order D COD D Visa D Mastercard Quality Microwave TV Antennas Acct # Exp. Date Multi -Channel 1.9 to 2.7 GHz. 40dB gain Signature - 30 Channel System complete $149.95 12 -Channel System complete $104.95 FOR OUR RECORDS 3 Channel System complete $79.95 DECLARATION OF AUTHORIZED USE - I, the undersigned, do hereby declare under penalty of perjury Phillips -Tech Electronics that all products purchased, now and ,n the future wtl only be used on cable TV systems with proper P.B. Box 8533 Scottsdale, AZ 85252 authorization from local officials or cable company officials in accordance wilt al applicable federal and LIFETIME (602) 947-7700 MOO Credit all phone orders') state laws. FEDERAL AND VARIOUS STATE LAWS PROVIDE FOR SUBSTANTIAL CRIMINAL AND CIVIL WARRANTY MasterCard Visa COO s I. uantity Pricine PENALTIES FOR UNAUTHORIZED USE.

Dated: Signed: DESCRAMBLERS. All brands. Special: Combo Jerrold 400 and SB3 $165. Complete cable de - scrambler kit $39. Complete satellite descrambler kit $45. Free catalog. MJM INDUSTRY, Box 531, Pacific Cable Company, Inc. Bronx, NY 10461-0531. T.V. tunable notch filters. Free brochure. D.K. VID- 73251/2 RESEDA BLVD., DEPT. R-11 RESEDA, CA 91335 EO, Box 63/6025, Margate, FL 33063. (305) 752-9202. (818) 716-5914 No Collect Calls (818) 716-5140 SURPLUS ELECTRONICS. New giant wholesale catalog. Hundreds of amazing bargains. $2. Box IMPORTANT: WHEN CALLING FOR INFORMATION 840, Champlain, NY 12919. Please have the make and model # of the equipment used in your area. Thank You

91 www.americanradiohistory.com CABLE TV MICROWAVE TV RECEIVERS 1.9 to 2.7 GHz SOUTHWESTERN Bell home, business phone CONVERTER products. Wholesale dealer pricing to all. 2 CH Compact Dish System -$77.95 Cordless phone & EQUIPMENT 5 CH Dish System - $93.95 battery, antennas, more. $5.00 refundable, 12 CH Vagi (Rod) System - $123.95 for dealer catalog. RADD, 104 S. Broadway, Peru, IN 30 CH Dish System -$163.90 Vagi -$183.90 46970. SUN MICROWAVE INT'L. INC. Send S10' for ...... CABLE TV descramblers, Jerrold, Scientific Atlan- P.O. BOX 34522 catalog on these ta, Zenith, PHOENIX. AZ 85067 and other line most major brands. Dealer inquiries wel- 1602) 230-0640 video products. come. Visa -M/C accepted. E & O VIDEO, 9691 E. VISA/MC/COD QUANTITY DISCOUNTS LIFETIME WARRANTY 265th Street, Elko, MN 55020. 1 (800) 638-6898. CABLE TV descramblers M35B tested, Vari - TUBES: "oldest," "latest." Parts and schematics. sync available $39.00. Rolex President a SASE for lists. STEINMETZ, 7519 Maplewood Ave., look -alike exact replica, goldtone, quartz RE, Hammond, IN 46324. 11111111 movement, mens or womens $39.00. (818) egg CABLE converters and descramblers. Call or write for free catalog. Includes Jerrold, Oak, Zenith, 982-8931. Hamlin, Scientific Atlanta, many more. NU -TEK FREE power supply, connectors ($8.95 value) ELECTRONICS, 5114 Balcones Woods Dr. immille #307, with TV project UNET UN TS Suite 298, Austin, TX 78759-5212. (512) 250-5031. assortment #103 (February 1984 G. Sync article) contains PCB, TOKO SCIENTIFIC ATLANTA W/ TRI -BI .. 225.00 175.00 coils, tran- .. IC's, PANASONIC WIRELESS TUBES, new, up to 90% off. SASE, KIRBY, 298 sistors (BF085), diodes, article reprint. $25.00. Five/$112.50. CONVERTER 1403N 85.00 ...74.00 West Carmel Drive, Carmel, IN 46032. Assortment #104 contains JERROLD 400 COMBO W/ REMOTE all other parts $10.00. Shipping $3.00. MC/Visa, (DRX3DIC) 134.00 ..100.00 COD accepted. JIM RHODES, INC., PO Box 3421, JERROLD 400 OR 450 REMOTE Bristol, TN 37625. HAND UNIT 24.00 ...15.00 TEST equipment pre -owned now at affordable JERROLD JR X 3DIC 84.00 ...65.00 SINGERS! prices. Signal generators from $50.00. Os- JERROLD SB ADD ON 74.00 ...55.00 9e. REMOVE VOCALS cilloscopes from $50.00. Other equipment, includ- JERROLD SB ADD ON WITH TRI -BI 95.00 ...75.00 FROM RECORDS AND CDs! ing manuals available. Send for Catalog. J.B. OAK M-35 COMBO 79.00 ...50.00 ..,. ELECTRONICS, 3446 Dempster, Skokie, IL 60076. OAK MINICODE (N-12) 84.00 ...59.00 (312) 982-1973. OAK ECONOCODE (E-13) 64.00 ...40.00 CABLE descramblers. SA -3 $89.00, TRI BI $79.00, HAMUN MW 1200 64.00 ...55.00 Tocom W/R $235.00, Z -TAC W/R $235.00, MLD SCIENTIFIC ATLANTA SA -3 ADD ON . 109.00 ...80.00 1200- 2 or 3- $45.00, RTC 56 W/R $150.00, 400 W/ INTERFERENCE FILTER R $125.00, all makes call (702) 647-3799. (CHANNEL 3 OR 6) 24.00 ...14.00 SCIENTIFIC ATLANTA 83 CHANNEL PC-ECAP, AC circuit analysis software for the IBM- CONVERTER 95.00 ...80.00 PC, will calculate and display the frequency and PIONEER CONVERTER BA 4500 phase response of your circuits. Very easy to use. SERIES 100.00 ...85.00 Completely menu driven. Supports CGA, EGA, and . +".-"-t TOMCOM VIP Call for price and availability Hercules graphics. High resolution plots on IBM/ ZENITH FLASHING Call for price and availability Epson printers. $99.50 To order or for info, write ZENITH SSAVI Call for price and availability CIRCUIT SYSTEMS, 418 Church Road, Sickler- EAGLE PD -3 Call for price and availability SING WITH THE WORLD'S BEST BANDS! ville, NJ 08081. An Unlimited supply of Backgrounds from standard stereo records! Record with your voice or perform live VIDEO -LINK with the backgrounds. used in Professional Performance yet connects easily to a home component stereo. This VOLTS P.O. Boa 1111-E Enterprises, Inc. unique product is manufactured and sold Exclusively by fr Placentia, CA 92670 M A NUTSß A Z I N E 714-632.7121 LT Sound - Not sold through dealers. Call or write for a 165 W. PUTNAM AVE. Free Brochure and Demo Record. GIVE YOURSELF A BREAK -A PRICE BREAK! NUTS & VOLTS WILL Site YOU MONEY GREENWICH, CT 06830 LT Sound, Dept.R L-3,7980 LT Parkway ON ELECTRONIC PARTS 6 EQUIPMENT Lithonia, GA 30058 (404) 482-4724 PITS SHOW YOU WHERE TO FIND UNIQUE, (203) 622-4386 Manufactured and Sold Exclusively by LT Sound UNUSUAL AND HARD -TO -FIND ITEMS. 24 HOUR PHONE DEMO LINE: /404!482-2485 SUBSCRIBE TODAY! MONDAY - FRIDAY 10 AM - 5:30 PM, E.S.T. L1 ANstie el Publication ForIleBeeAniSellingOf&eitronieEquipeent IMPORTANT: Have make and model # of the equipment used in your area. ENGINEERING software, PC/MSDOS. Hob- byists - students - engineers. Circuit design, FFT analysis, mathematics, logic ACCEPTING new customers again for our monthly OUTPUT PRICE TOTAL picture flyer. Lots of quality electronic surplus parts. OW ITEM CHANNEL EACH PRICE simulation, circuit analysis. Free catalog, STAR-TRONICS, Box 683, McMinnville, OR 97128. (614) 49-1-0832, BSOFT SOFTWARE, 444 KEYBOARD? Phaser-chorus-reverb unit makes lit- Colton Rd., Columbus, OH 43207. tle keyboards sound big, using your component stereo system; also guitars. $88.00. PLEX, HCR 61, RESTRICTED technical information: Electronic Box 6050, Barnes, WI 54873. NO CONNECTICUT SALES. It SUBTOT. surveillance, schematics, locksmithing, covert sci- is not the intent of VIDEO-LINK Shipping ences, hacking, etc. Huge selection. Free bro- RFI suppression ferrites one and two hole beads to defraud any pay television $3 / Unit chures. MENTOR -Z, Drawer 1549, Asbury Park, NJ with misc. assortment ferrite shapes baluns, cups, operator and we will not assist threaded cores, I.F. bases, coilforms, powdered iron COD: 07712. any company or individual in cores, Add 5% your cost $19.95 prepaid in U.S.A.. Postal doing so. CABLE TV converters and descramblers bar- money order for fast shipment. Your check takes ten TOTAL gain headquarters! Zenith, Hamlin, Scien- days to clear bank. REDELABS, 3405 North Ken- PLEASE PRINT: icot, Arlington Heights, IL 60004. tific Atlanta, Tocom, Oak, filters. Jerrold CASHIER'S CHECK M.O. C.O.D 400-DRX3DIC w/remote - NAME $134. Visa -M/C COD. Order yours today. 1 (800) 327-8544. ADDRESS PLANS AND KITS CITY/STATE/ZIP CABLE TV converters and descramblers. PHONE BUILD this five -digit panel meter and square -wave We sell only the best. Low prices. SB -3 SIGNATURE generator including an ohms, capacitance and fre- $79.00. We ship C.O.D. Free catalog. ACE quency meter. Detailed instructions $2.50. BAG- WAIVER. Since I, Ile undersigned, fully PRODUCTS, PO Box 582, Dept. E, Saco, ME NALL ELECTRONICS, 179 May, Fairfield, CT understand that the ownership of a cable decoder 06430. does not give the owner of ti , decoder the right to 04072. (207) 967-0726. decode or view premium cable channels without STEREO FM transmitter!. Transmit your VCR/CD/ proper authorization from their local cable company, STEPPER motor drive & control with Commodore Walkman to any FM stereo radio. One chip does it hereby declare under penalty of perjury that all 64. Affordable hardware, interface, & software. all! Free schematic and info. Send a self addressed/ products purchased, at any time, will only be used Send for detailed literature & prices to: MASE, R.D. stamped envelope to: DJ INC., 847A Second Ave., on cable TV systems with proper authorization from #2 Box 166, Mohrsville, PA 19541. Suite 113, New York, NY 10017. local officials or cable company officers in accordance with all applicable federal and state FEB 87 Triparts $59.00. Feb 84 SB parts $49.00. FM transmitter 88 to 108 MHZ kit $12.95. SIERRA laws. Federal and various state laws provide for $3.50 shipping. OCTE, Box 276, Alburg, VT 05440. ELECTRONICS, Box 709, Elfers, FL 34680-0709. substantial criminal and civil penalties for (514) 739-9328. unauthorized use. ELECTRONIC kits! Transmitters! Recorders! RENTAL movie stabilizer. Connect between VCRs Phone devices! Bug detectors! Surveillance items! Dated: Signed: or to monitor. Satisfaction guaranteed. $69.95, More! Catalog $1.00: XANDI ELECTRONICS, Box $4.00 handling. 1 (800) 367-7909. 25647, 60W, Tempe, AZ 85285-5647. CIRCLE 64 ON FREE INFORMATION CARD 92

www.americanradiohistory.com INIOUTCING...

.) 7.-) ? f)=> 13.an .a 1F3r3A nq;rlflnC>Ip-, wo RLD c . . 1 RSF IUUENCY PERIOD.... RAT10 INTERVAL AVERAGE PRESCALE OVERANGEtM"s A D Rz pS . . nS High Performance 0.11 0.1 1.0 10 10u no LOW BATT 1.111111111ifilin Universal Counter Timer Module/Panel Meter ACTUAL SIZE 10 Digit (120 Segment) LCD Display with Gate, Function, and Input Annunciators.

.1 f -z to Over 150 MHz Direct Count (1 Hz resolution in 1 Sec).

SinDIe Shot Time Interval 100 ns, .1 ns averaged. Functions Include: Frequency, Period, Ratio, and Time Interval and Average. 16 Segment Analog Input Bargraph is driven by an 8 Bit A to D and Can Be Used for Signal Level Display. Low Power (250 mw) with Single 5v Supply.

OPTOELECTRON/CS INC. Hiçh Accuracy, 1 ppm 10 MHz Crystal Time Base with Cal 5821 N.E. 14th Avenue Fort Lauderdale, Florida 33334 Acjust on Board. (800) 327-5912 FL (305) 771.2050 FAX (305) 771.2052 EcDnomical to Use in Custom OEM Applications. CIRCLE 186 ON FREE INFOReIATION CARD

INVESTIGATORS, experimenters - Quality new plans Hard to find micro and restricted devices. Free catalog. Self addressed stamped envelope to CABLE RENTERS FINALLY! KELLEY SECURITY INC., Suite 90, 2531 Sawtelle An interesting and worth- Blvd., Los Angeles, CA 90064. STOP! while project. This EASY- If your currently renting your cable equipment it's time to TO -BUILD circuit lets you CB Tricks II book. Power amplifier design and theo- look into your You can use any regular TV set es ry, UHF CB tune ups. Send $19.95 MEDICINE MAN owning own. save upto$100 plus e simple OSCILLOSCOPE. CB, PO Box 37, Clarksville, AR 72830. every year. Satisfaction Guaranteed. DETAILED PLANS: $7.95 No modifications to TV! Tiny, 9v battery powered. We carry all the major brands of Converters. TV -SCOPE Goes anywhere! Order now! PENN RESEARCH, Box 3543 Ask for our FREE CATALOG Remote controls and Descramblers. JERROLD, OAK, Williamsport, PA 17701 of other plans end kits! REMOTE CONTROL KEYCHAIN ZENITH, EAGLE, HAMLIN. SCIENTIFIC ATLANTA. Complete w/mini-transmitter Many more. Fast courteous service. CB tricks booklet. Modifications, tune-ups, chan- and +5 vdc RP receiver Fully assembled including plans Call today 512-250-8816 or write for your nel expansion, clarifier tricks. Send $19.95 to MEDI- to build your Dwnsauto alarm VISA Free catalog. CINE MAN CB, PO Box 37, Clarksville, AR 72830. Quantity discounts available ó PRINTED circuit boards etched & drilled. Free deliv- Q Check Visa org /C D. Free $ 19.9) Add $3 shipping et 1-80I-228-7414 ery. K & F ELECTRONICS, INC., 33041 Groesbeck, Nu -Tek Electronic 5114 Balcones Woods dr. Fraser, MI 48026. (313) 294-8720. VISITECT INC. /Dept. R (415) 872-0128 PO BOX 5442 SO. SAN FRAN CA 94080 Suite#307 De t.298R Austin, Tx 78759 RADIO astronomy! Monthly magazine, books, components. $3.00 brings sample package. BOB'S ELECTRONIC SERVICE, 7605 Deland, Ft. Pierce, PROJECTION TV. Convert your TV to project 7 foot FL 34951. DAZER protector kit $44.95! Exciting electronic kits! picture... Easy... Results comparable to $2,500 proj- Catalog $1.00. QUANTUM RESEARCH, 17919-77 ectors... Plans and 8" Lens $24.95... Professional CATALOG: hobby/broadcasting/HAM/CB: Cable Avenue, Edmonton, Alberta T5T 2S1. systems available... Illustrated catalog free... TV, transmitters, amplifiers, surveillance devices, MACROCOMA, 15GB Main Street, Washington computers, more! PANAXIS, Box 130-F11, Para- DETECTION - Surveillance, debugging, plans, Crossing, PA 18977. Creditcard orders 24 Hrs. (215) dise, CA 95967. kits, assembled devices. Latest high-tech catalog 736-3979. $5. DETECTION SYSTEMS, 2515 E. Thomas, SURVEILLANCE equipment design gives 58 #16-864F, Phoenix, AZ 85016. SOLAR education kit. Soldering unnecessary. So- schematics of Sheffield Electronics surveillance de- ALPHANUMERIC advertising display. Micro- lar cell drives 0.45 volt electric motor & fan. Under- vices. Circuits explained. Transmitters range from standable booklet tells how it graphics. Pro- works and much more. pens to one-mile VOX's including crystal, subcarrier, processor controlled. Eye-catching Ages grammable. Stores 6000+ characters. Detailed 6 to adult. $10.00 + 6% California residents. carrier current, infrared, firefly, automobile. Demod- Extra cells, $4.00 each. Checks only. Quantity dis- plans $4.50. PLANET EARTH, PO Box 613, Edin- ulators given. Cube tap and duplex mains powered counts. 1840 TX 78540. SOLAR WINDS, Jeffrey Lane, Car- transmitters presented. Eighteen telephone trans- burg, micheal, CA 95608. mitters are leech and battery types including crystal ELECTROLOCK programable keypad door release BUILD your own PA, Guitar, Bass systems. Product and subcarrier. Countermeasures chapter. Much system, complete kit including electric strike release more. This 81/2 x 11 inch 110 is designers for major electronic companies! Consum- -page book illustrated and manual $129.95. Brochures and orders: SYS- with photographs. Price + $4.00 er direct! Plans: PA's 8-24 channels 4-16 outputs $30.00 S & H. First TEMS ASSOCIATES INC., 1320 Cranston Street, class mail & S & H $19.99. 32 channels 16-24 outputs $29.99. U.S. Canada. Overseas Airmail Cranston, RI 02920. (401) 943-2986. Stereo $9.00. One -day processing, pay with Money Order rack mount amp 300w, 600w $19.99. Parts, com- or Cashier's Check. Send to: WINSTON AR - KIT catalog - Automotive, Audio, Phone, Sports, plete kits, additional plans available. M.O., certified RINGTON, 7223 Stony Island Ave., Chicago, IL Surveillance, Test. Catalog $1.00. BALLco, PO Box check only. DCS, Box 612, Alpha, IL 61413. (309) 60649-2806. 1078, Snellville, GA 30278-1078. 667-2553.

93 www.americanradiohistory.com CABLE TV PAY TV AND SATELLITE DESCRAMBLING DESCRAMBLER: Build our low cost video only, DESCRAMBLERS NEW... 1989 EDITION... NEW satellite TV descrambler for most satellite channels. 10 Lot JERROLDD' Tri-Bi Mode. $105.00 $85.00 The newest systems, parameters, turn-ons, harassment and Uses easy to get, everyday parts. Boards & plans WC. .) $35.00 US funds. Board, plans & parts $99.00 US JERROLD", SB -3 OR 2 $89.00 $65.00 O } 11-1 countermeasures being used by and against cable, wireless and satellite operators. New original information $15.95. Pay funds. Wired & tested unit $189.00 US funds. Send HBmlin MLD-1200 $99.95 $62.00 Z z it TV Vol. 1 Volume 2 Experiences with VC Oak N-12 W/V S.._ $99.95 $62.00 $14.95. $12.95. check, money order or Visa to: VALLEY MICRO- O < ,CLN $12.95. MDS/MMDS Handbook $9.95. Build Satellite Sys- WAVE Oak -M -35-B W/V.S $99.00 $78.00 CC ELECTRONICS, Bear River, Nova Scotia, i ia` tems Under $600. $12.95. Any 3/$28 or 6/$42. Scrambling Canada BOS 160 or phone (902) 467-3577. 8am to OAK E-13 $99.95 $58.00 I- O News Monthly $24.95/yr. Sample $3. Scrambling News Year Q 4pm eastern time. Note: educational project only. Zenith SSAVI $185.00 3145.00 O H (200 pages) $22.95. New Spring Catalog $1 or call. Eagle PD -3 $85.00 W H 2 Not to be used illegally. $120.00 < crambling News, 1552 erte 've., :u' a o, Scientific Atlanta.. $129.95 $105.00 2 L 0 W N.Y. 14216 COD's SA-Combo's CALL SCali J W1 716-874-2088 Tocarn. $350.00 $295.00 I J 2i H Oak N-12 W/ Auto $140.00 $105.00 Q Z Jerrold Starcem CSV $139.95 Call SATELLITE TV #### *PRESENTING ## -sr ## *NEW STARGA'l'h 2000 CABLE TV secrets - the outlaw publication the CABLE TV cable companies tried to ban. HBO, Movie Channel, DESCRAMBLERS CABLE CONVERTER Showtime, descramblers, converters, etc. Sup- ##### STARRING ##### plier's list included $8.95. CABLE FACTS, Box 711- JERROLD, HAMUN, OAK R, Pataskala, OH 43062. AND OTHER FAMOUS MANUFACTURERS FREE catalog systems, Upgrades, Houston, Uni - FINEST WARRANTY PROGRAM AVAILABLE LOWEST RETAIL/WHOLESALE PRICES IN U.S. den, Chaparral, etc. Save $$$$$. SKYVISION, ORDERS SHIPPED FROM STOCK WITHIN 24 HOURS 2009 Collegeway, Fergus Falls, MN 56537. 1 (800) - FOR FREE CATALOG ONLY I-SOO-345-S9=7 -.. 334-6455. FOR All INFORMATION 1-818-716-5914

`.,._-) PACIFIC CABLE CO. INC. 11 SCRAMBLE FACTS 7325', RESEDA BLVD.. DEPT. RE1 89 1-$89.00 10-$69.00 100 -Call RESEDA. CA 91335 Last channel recall -Favorite channel select - 718-343-0130 75 channel -Channel scan -Manual fine tune - One year warranty -surge protection-HRC & Stand- PHONE TODAY for 3 minutes of DESCRAMBLERS for movies, networks, $175, video only, $450 complete. Visa, MC ard switchable- and much more. Call Today! accepted. Cata- satellite TV industry news,technical log $4. SKYWATCH, 238 Davenport Road, Toronto, INFORMATION(402)554-0417 tips, and new product information. Canada, M5R 1J6. Orders Call Toll Free 1-800-624-1150 VIDEOCIPHER II manuals. Volume 1- hardware, Volume 2 - software. Either $32.45. Volume 3 - FOR INVENTORS M.D. ELECTRONICS projects/software - $42.45. Volume 4 - repair - 115 NEW YORK MALL $97.45. COD's (602) 782-2316. 0100-032 software. INVENTORS! Confused? Need Help? Call IMPAC MC. Catalog -$3.00. TELECODE, Box 6426-R, Yuma, for free information package. In U.S. and Canada: 1 SUITE 133E AZ 85366-6426. (800) 225-5800. OMAHA, NE. 68114 cáó CIRCLE 53 ON FREE INFORMATION CARD

Stop Paying For All Those Catalogs Sent To The 'Current Residents.'

Facts are that a 2% response to a mailing of Catalogs by a Mail -Order House is considered phenomenal and most Direct Marketing Firms consider a 1% reply quite adequate. The question is who pays for those 98 to 99 Catalogs that are thrown away as "Junk Mail" or do not generate a response? It is you, as a bonafide customer of the Mail -Order Company who have to pay for the cost of publication and mailing of all those wasted Catalogs. Granted that the Company doesn't bill you directly for its cost but rest assured that you pay for it through higher prices. So when we ask our potential Customers for an annual Membership Fee of $35, it is because we want each Customer to pay just for his or her own Catalogs and not for the cost of the other 98 Catalogs going to 'the Current Resident.' And we have had Members who have paid the annual Membership Fees for years without buying anything at all or very little throughout a year. But other Members did not have to pay for their Catalogs. Without having to spend, or better said 'waste', hundreds of thousands of Dollars on production and distribution of unwanted Catalogs, we pass on the savings to you in form of prices that are 20% to 70% lower than elsewhere 12 Months Saving Guarantee and our 30 Days Money Back Guarantee We will refund the first year Membership "Savings Guarantee" proves it. So if We will refund the full Membership Fee of any member who has purchased you buy $300 or more a year worth Fee of any new member of Electronic $300 or more worth of products from of electronic components stop Buyers Club who within 30 Days Electronic Buyers Club and has not paying for waste and start saving after receiving the Membership saved an amount greater than the first Binder, returns the Binder to EBC year Membership Fee, if buying the same now. Call us today to become a and asks for the cancellation of items elsewhere. Member of Electronic Buyers Club. Membership.

electronic 1803 N.W. Lincoln Way Toledo, OR 97391 uyers club PHONE (All 50 States & Canada): 1-800-325-0101

A Division of International Components Corporation FAX: (503) 336-4400 Hours: 6:00 AM - 6:00 PM PST

94 CIRCLE 178 ON FREE INFORMATION CARD

www.americanradiohistory.com 508 Central Ave. ICRO Weetlield, N.J. 07090 (201) 6544008 ART DIODES &

IM17415 1 174XX1 140001 1LINEARI TRANSISTORS 741500 14 74D6 26 4001 18 1M309K 75 MRF901 IC 741.502... .12 7427 12 4007 79 L1'311... .37 1N914 40/57

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741508._. .16 7437 _.. 25 4024 ._. .39 LM339.... .37 I N4004 25/51

741.510... 16 7438. .. 23 4051 . 49 I.M380 . 79 1194007 15/$1 744.514. .28 7439.... 35 4066. .29 LM393.. .36 1194148 40/5, 741520 16 7447 75 4069 18 NE555 25 282222 10 74L521... .18 7474... .24 4082 19 L11556.... 45 2192904 .20 741532. 16 7476.... .34 4093. 34 101741. 27 2142907 10 741.573.. 25 7483 48 4511 .60 MC1330 150 2N3055 6C 74t 974 18 7492. 48 4538 75 MCI 398 35 283904 10 744.575... 25 74116... 95 MC1458 32 2193906 1C 741576.. 28 74145.. 35 EPROMS 11139CC 4E 284249 1C 74E5148 80 74148 95 27160 95 MC78057 44 284401 IC 7445163. .34 74163.._.55 2732-25 350 MC78 21 44 F15E 216 74L5257. 28 2764-2 3 95 MC74M24T 44 TO -92 NPh 04 741.5299. .95 27128-25 4 15 MC7905T. 44 250708115 40 7415393 .60 27256-2 550 MC7912T 44 2EN126755NPN 74SCXX HS 27512-2 10.50 MC79151 44 .WR AMP 1C-220 35 LOW PWR TTL CAPACITORS DIGITAL MULTIMETER MDL 7051 7450137 25 0019F IKV DISC 03

7450138 25 . OIuF 1006 MYLAR 05 7450,39 25 1uF 30V MONO 08 7450237 .30 .22 50V MONO IO 7415239 30 .33 uF 50V MONO 10 7450240 30 47uF 50V MONO I O $519s 7450241 30 41 F 40V RADIAL 03 7450245 30 22uF 35V TANT 33 7450373 35 1 OCOfF 25V RAD. 25 CzpacHors 14 to 20,F 7450374 35 3 300uF 35V AlliAL 65 AC Volt 1 OOu9/7502 AC Amp 0.1uA/1OA 7450534 35 13/4 LEDS DC Volt 10 ,V/1000V DC Amp 0 Ima/10A 7450533 .35 DIFFUSED LENS Dmee Test FWD Volt tost 7430540 35 RED 75/31 130/$6 H7e Sran5,5tOr test

7460563 35 GREEN 10/51.30 103/$13 Hi -Lo OHMS 0 1 to 20M YELLOW 10/51.40 100/5111 SPECIALS SPECIALS SPECIALS MANY MORE ITEMS IN STOCK AND AVAILABLE FOR FAST DEL VERY Brought To You Bg CATALOG INFORP1ATION CATALOG FREE WITH ORDER, OR SEND .45 POSTAGE FOR 1ST CLASS DELIVERY N U.S.A 52 POSTAGE FOR CANADA OR CRCLE BINGO CARD NUMBER AT THE BOTTOM OF THIS AD FOR 2ND CLASS MAIL MCM Electronics W :MICRO MART ACCEPTS PRE -PAD ORDERS, CHECKS, MONEY ORDERS, VISA, MC, MD TELEPHONE COD'S. MN p411 ORDER 51000 SHIPPING- US .A ORDERS $250, CANADA $350 AND UP TO 1E9. SHPPNG RATE ADJUSTED WHERE APPLICABLE NJ RESIDENTS ADD 6% SALES As an experienced service technician, you too TAD rely on the tools of your trade to achieve the MICRO MART 508 CENTRAL AVE, WESTFIELD, NJ 07090 must results your customers have I 201-654-6008 kinds of professional every right to expect. CIRCLE 63 ON FREE INFORMATION CARD To get the "tools" you need... when you need them, look no further than the MCM Electronics Catalog. Our huge inventory of more than 11,000 in -stock items, competitive prices, convenient TOLL - is hidden behind the car's FREE phone lines, super -fast order processing and NEW PRODUCTS dashboard. It is available in flexible payment terms make MCM your best three models. The basic de- continued from page 28 choice for all your parts and components needs. vice simply turns the car Get your hands on an MCM Catalog today stereo on and off. Another and find out why thousands of satisfied MCM cus- strations are also provided. model can either turn the tomers come to us for the "tools" that keep them at "A Video Standard" (cata- stereo on and off, or turn off the top of their trade! log number LD-101) has a just the speakers. The third suggested retail price of For Your FREE mom MCIN ElE'L114UNü, $59.99. -Reference Record- ONE-YEAR MCM ings, Box 77225X, San Fran- cisco, CA 94107; Tel. SUBSCRIPTION Electronics 415-359-8721. to the MCM rafalOg Electronics .4 CELLULAR -PHONE AC- Catalog... CESSORY. Designed to help CALL TOLL -FREE drivers avoid the scramble to shut off the car radio 1-800-543-43 when the cellular phone CIRCLE 17 ON FREE rings, Sound Quest's Si- INFORMATION CARD lencer turns off the stereo model is designed for use system a moment before with high -end stereo sys- the phone rings. Drivers tems that have additional can hear their phones ring amplifiers. It interrupts the Source No. RE -61 more easily, and keep their stereo signal before it attention on the road. As reaches the amplifier. soon as the phone is hung The Silencer has sug- up, the music comes on gested retail prices ranging MCM ELECTRONICS 650 CONGRESS PARK DR. again. from $39.95 to $69.95. - CENTERVILLE, OH 45459-4072 The Silencer is a small Sound Quest, 2250 Green- A PREMIER Company black box, about the size of field Ave., North Chicago, a remote -control unit, that IL 60064. R -E CIRCLE 87 ON FREE INFORMATION CARD 95 www.americanradiohistory.com ASSEMBLE YOUR OWN DESCRAMBLER MODULE COMPUTER FOR LE$$ LATEST technology alternative to Jerrold SB -3 or AMAZING Radio -Electronics Feb. 1984 project. Featuring IBM XT 10 MHz Compatible Kit $379 electronic tuning, AGC, auto-on/off, AC/DC power, SCIENTIFIC & ELECTRONIC 4.77/10 MHz Motherboard mini -size, A&T, and more. For literature - SOUTH - 256KB RAM (840KB max) TECH DISTRIBUTING, (813) 527-2190. PRODUCTS 150W Power Supply Floppy Disk Controller PLANS One 51/4 380KB Drive Build Yourself - All Parts Available in Stock MonoGraphics Card w/ P ICI- BURNING CUTTING CO2 LASER $20.00 INVENTORS PORTABLE 101 Key Keyboard RUN- LASER RAY PISTOL $20.00 * xeuw 7CC7- 3 SEPARATE TESLA COIL PLANS T01.5 MEV $25.00 Case (3LED,2Button,Key) INVENTORS! Can you patent and profit from your Kw- ION RAY GUN $10.00 12' Amber Mono Monitor idea? Call AMERICAN INVENTORS CORPORA- GRA1- GRAVITY GENERATOR $10.00 Installation Guide & Manual TION for free information. EMIL- ELECTRO MAGNET COIL GUN/LAUNCHER $8.00 Over a decade of service IBM AT 12 MHz Compatible Kit $705 1 (800) 338-5656. In Massachusetts or Canada call (413) KITS 8/12 MHz Motherboard 568-3753. With AK Necessary Plans 512 KB RAM (4 MB max) MFT31I- FM VOICE TRANSMITTER 3 MI RANGE 549.50 VWPW7K- TELEPHONE TRANSMITTER 3 MI RANGE $39.50 200W Power Supply BTC3K- 250,000 VOLT 10-14" SPARK TESLA COIL $249.50 Floppy Disk Controller LHC2K- SIMULATED MULTICOLOR LASER $44.50 One 5 1/4' 1.2 MB Drive - DIGITAL CAR DASHBOARDS BLS1K-100.000 WATT BLASTER DEFENSE DEVICE $69.50 MonoGraphics Card w/ P 111G7K--NEGATIVE ION GENERATOR KIT $34.50 101 Key Keyboard BUILD yourself PSPIK- TIME VARIANT SHOCK WAVE PISTOL $59.50 complete electronic dashboards. STAIE- ALL NEW SPACE AGE ACTIVE PLASMA SABER 959.50 Case (3LED,2Button,Key) Informational package: $2.00 (refundable). MOD- SDSR-SEE IN DARK VIEWER KIT $199.50 12' Amber Mono Monitor,; ERN LABS, 2900-F Ruisseau, Saint -Elizabeth, P95K-PLASMA LIGHTNING GLOBE KIT $49.50 Installation Guide & Manual ', QC, JOK 2J0, Canada. ASSEMBLED Display Upgrade: Hard Drive Option: With All Necessary Instructions CGA Package $200 20MB w/CTRL XT -$275 AT -$315 B7CIO- 50,000 VOLT-WORLDS SMALLEST TESLA COIL $54.50 EGA Package $455 30MB w/CTRL XT -$310 AT -$410 LGUI0-1MW HeNe VISIBLE RED LASER GUN $249.50 VGA Package $500 40MB w/CTRL XT -$390 AT -$415 TAT38- AUTO TELEPHONE RECORDING DEVICE $24.50 MS-DOS with GWBASIC $75 RM10-100,000 VOLT 20' AFFECTIVE RANGE CABLE T.V. CONVERTERS INTIMIDATOR $99.50 All Componants Fully Tested Before Ship WHY PAY A HIGH MONTHLY FEE? UST1O- SNOOPER PHONE INFINITY TRANSMITTER $169.50 VISA & M/C subject to 3% surcharge IPG70- INVISIBLE PAIN FIELD Price & Quantity subject to change without prior notice GENERATOR MUTLI MODE $74.50 15% Restocking Fee on All Items CATALOG CONTAINING DESCRIPTIONS OF ABOVE PLUS HUNDREDS MORE AVAILABLE FOR $1.00 OR USE OUR JINCO COMPUTERS INC. PHONE FOR "ORDERS ONLY' 603-673-4730. PLEASE INCLUDE $3.00 PH ON ALL KITS AND PRODUCTS 5122 WALNUT GROVE AVE. PLANS ARE POSTAGE PAID. SEND CHECK. MO, VISA, MC IN US FUNDS. SAN GABRIEL, CA 91776 INFORMATION UNLIMITED Tel: (818) 309-1108 P.O. BOX 716 DEPT. R E AMHERST, NH 03031 Fax: (818) 309-1107 IBM, XT, AT are registered trademarks of All Jerrold, Oak, Hamlin, Zenith, Scientific International Business Machine. Atlanta, Magnavox and all specialized cable CIRCLE 184 ON FREE INFORMATION CARD equipment available for shipment within 24 hours. For fast service MC / VISA or C.O.D. EDUCATION & INSTRUCTION telephone orders accepted (800) 648-3030 60 Day Guarantee (Quantity Discounts) FOR 1 MAGIC! Four illustrated lessons plus inside infor- 3 A.M. P.M. mation shows you how. We provide almost 50 tricks 8 to 5 C.S.T. CLOSED WEEK- including equipment for four professional effects. ENDS. Send self-addressed Stamped enve- You get a binder to keep the materials in, and a one- lope (60e postage) for Catalog. SPECIAL year membership in the International Performing Magicians with a plastic membership card that has I P.O. Boo 5000 MIDWEST your name gold -embossed. You get a one-year Suite 311 IR) sub- ELECTROfTICS If1C. ON SUB -MINIATURE VOICE scription to our quarterly newsletter "IT's MAGIC!" Carpentersville, IL 60110 Order now! $29.95 for each course + $3.50 postage FM No Illinois Accepted. TRANSMITTERS. and handling. (New York residents add applicable Orders state and local sales tax). THE MAGIC COURSE, KITS CONTAIN PC BOARDS 500-B BiCounty Boulevard, Farmingdale, NY 11735. LEARN IBM PC assembly language. 80 sample BUSINESS OPPORTUNITIES programs. Disk $5. Book $18. ZIPFAST, Box 12238, Q. Lexington, KY 40581-2238. EASY work! Excellent pay! Assemble products at home. Call for information. (504) 641-8003 Ext. PROGRAM your own computer simulations and 5192. learn how to analyze circuits. New periodical will 'FMX-1 LONG RANGE (3 MI) ULTRA SENSITIVE show you how to analyze filters, phase locked loops, MAKE $50/hr working evenings or weekends in FM VOICE XMTR with fine tune, range control your own electronics business. Send for free facts. plus $29.50 etc. Complete with basic subroutines you can use in your own programs. Only $10.00 per issue or INDUSTRY, Box 531, Bronx, NY 10461. $100.00 for 12 issues. DESIGN LETTERS, PO Box YOUR own radio station! AM, FM, TV, cable. Li- 251, Gaithersburg, MD 20877. censed/unlicensed. BROADCASTING, Box 130- F11, Paradise, CA 95967. INVENTIONS, ideas, technology wanted for pre- WANTED sentation to industry/exhibition at national innova- 'TELX-1 TELEPHONE FM XMTR (3 MI) auto- tion exposition. Call 1 (800) 288 -IDEA. SEISMOMETER wanted to measure earthquakes. matically operates when phone is used. Crystal ASSEMBLE digital dashboards. Details $2.00. clear clarity with fine tune and range control. Pay cash. D. HUTCHISON, 4000 Little Timber, Ed- MODERN mond, OK 73034. (405) 341-9615. LABS, Digidash Division, 2900 Non detectable $29.50 Ruisseau, Saint -Elizabeth, Quebec, JOK 2J0, Can- INVENTIONS/new products/ideas wanted: Call ada. ._ TLCI for free information 1 (800) 468-7200 24 hours/ day - USA/Canada. MAKE $75,000 to $250,000 yearly fixing IBM r! . monitors, no investment, start from home, (a tele- WANTED used photofact folders 1800 and up. Write phone required). Information USA. Canada $1.00, to URIEL REY, 1408 Venustiano Carranza St., Europe, Middle East $8.00. RANDALL DISPLAY, *ATR-1 AUTOMATIC TELEPHONE RECORDING Chihuahua, Chih. Mexico. Box 2168-R, Van Nuys, CA 91404 USA. DEVICE tapes telephone conversation all automatically $19.50 PROJECTION TV... Make $$$'s assembling proj- ectors. Easy!... Results comparable to $2,500 proj- ALL THREE OF ABOVE FOR $59.50 ATTENTION CABLE BROKERS ectors... Plans, 8" Lens & dealers information $22.50... Professional systems CALL OR SEND VISA, MASTER CHARGE, available... Illus- SURPLUS CATV converters and descramblers at trated catalog free. MACROCOMA, 15GBX MONEY ORDER, ETC. TO AMAZING CONCEPTS, Main wholesale prices. Unmodified units only. Oak M35B Street, Washington Crossing, PA 18977... BOX 716, AMHERST, NH 03031. (603) 673-4730. Credit- $30. Jerrold 400DIC w/rem $80. (415) 566-9815. card orders 24 Hrs. (215) 736-2880.

96 www.americanradiohistory.com THE ELECTRONIC GOLDMINE

-N _ Send for your copy of our 1989 catalog hacker tech venture, you might featuring hundreds of electronic components HARDWARE HACKER and unique electronic project kits,. Each of want to check into my Incredible , e.... A our project kits include all necessary parts Secret Money Machine book. a continued from page 73 and glass epoxy etched and As always, this is your column -ee drilled PC board - you only need to = T solder in the parts and provide o and you can get technical help and battery Ion battery operated kits) grated circuits. Try to get the fat off-the-wall networking per the Nero are two examples of our Unique Kits! Japanese book as well as the thin Need Help? box. R -E 1 English one. MINIATURE GEIGER COUNTER KIT Heath Electronics is a brand- Miniature acre ndICountroterd tioneets lock, gamma and Kroy radiation. Erdh new hacker publication. They are asks from peso speaker in proporton to CABLE TV intently. Features sensitive alpit window looking pay- GM Tube end IC circuit Operates on 9V for authors, but their DESCRAMBLER LIQUIDATION! 6oltey (not iea1C Sow ment rates are chintzy. For more 4301 Major Makes & Models! info, contract Ed Mosher at the - LIGHTNING -BOLT - Will match or beat anyone's prices! STROBE LIGHT KIT Heath Buyers Club. Powerful 120VAC Strobe Kt praduses Dealer discounts at 5 units! brilliant fleshes of Sght from mammoth A free printer on spectrum anal- 3 VT long xenon tube. Hm control to vary Examples: flash rate from 30 to 400 per h ule. ysis is available from Tektronix, Coulon - this Ail a for wisdoms' builders HAMLIN COMBOS $44 ea. (Min. 5) only (due to high voltage). Ssa: 3.4 o S while Brookfield has lots of free (6431 $34.95 Mahe .. OAK ADD/ON $40 ea. (Min. 5) ap-notes available on viscosity OAK M35B $60 ea. (Min. 5) measurement and control. Fabulous Component Values! WEST COAST ELECTRONICS SURFACE MOUNT CHIP COMPONENTS Turning to my own products, CAPS aESIST For Information: 818-709-1758 7p1 I0 220 I SF 22K 361 I've just finished my new 39 270 1.K 39K YOUR 01010E - Catalogs & Orders: 800-628-9656 47 390 2.21 681 ANY 0111 YAluF OF to PostScript video- I 56 470 3.31 4701 1105109 09 Introduction I pl 82 560 125 CAPACITOR IS 720 IS 180 12K 20/S100 at 100/S4.00 tape, and have now book -on -de- 100pf Ito 1.21 151 (NO MIRING) mand published a series of INVERTER TRANSFORMER Tiny 4 had dormer fa use eh MI( le craven I oVoc o over 2SOY la reprints from my LaserWriter Cor- NEW HE NE strobes, florescent tube; ea Simple sAw er, iduded. NI 703 52 tech 100lot 5170 ner, originally found over in LASER TUBES $35 41(Vroe RCOIL magazine. In- Dealer Inquiries Invited. 31"d woo a1toto Tie coos0 Admits. Computer Shopper 1111005115 eoA 100 for SBO cluded are over three dozen free Free Catalog! MINIMUM ORDER S 10.00 plus 3.00 shipppi9 and hondliny We accept NI/C, MEREDITH INSTRUMENTS: 6403 N. 59th Ave. Visa ondl money orders, (0D lee: 2.50 in addition to 3.00 shipping charge. and unique PostScript fonts. For Glendale, AZ 85301 (602) 934-9387 SEND ORDERS TO: The Electronic Goldmine P.O. Boo 5408 Scottsdale, AZ. 85261 those of you starting up your own "The Source for Laser Surplus" PHONE ORDERS: (602) 451-7454

CIRCLE 187 ON FREE INFORMATION CARD

18" EMINENCE WOOFER R MADE IN USA Parts I e MOTOROLA Pdlydax EMINENCE O 100 oz. magnet, 3" voice Ex veers coil. 250 watts RMS, 350 International Inc. watts max. 8 ohm, 30 Hz lr! PHDNEU2 resonant frequency. 22- 1-800-338-0531 2700 Hz response. Efficiency: 95 dB 1W/1M. 3 -WAY 100W CROSSOVER 12" SUB Paper cone, treated WALNUT SPEAKER WOOFER accordion surround. Net Dual voice coil sub woofer. weight: 29 lbs. CABINET KIT,. 30 oz. magnet, 2" voice 12 dB/octave rolloff. Super quality, coils. 100 watts RMS, 145 800Hz, 5000Hz $98.90 $89.50 genuine walnut watts max. fa =25 Hz. 6 ohm #290-200 (1-3) (4 -up) crossover points. 8 veneer cabinet. Kit (4 and 8 ohm compatible). ohm. 100 watts RMS. includes: routed and SPL=89 dB 1W/1M. TITANIUM COMPOSITE $12.50 $9.95 mitred top, sides, Response: 25-700 Hz. #260-210 (1-9) (10 -up) and bottom in QTS=.31, VAS= 10.3 cu. ft.. TWEETER unfinished 3/4" Pioneer #A3OGU30-55D. Titanium ts deposired one polymer SPEAKER CONTROL walnut veneer. Cut Net weight 6 lbs dare to combine Ne advantages of your own custom $33580 $36.80 bah Fard and edt donee #290-145 ted,ndogiea 8 olun. Ferro fluid PANEL holes in the front (4-u cooled voice coil. Cs = 1200 Hr

Panel with 50 wan L -pads and rear to match SPL = 90 dB 1 W/1M. 50 watts RMS. for tweeter and midrange your drivers. 15" x 15" THRUSTER WOOFER 70 swans ersea. 4" round Polydes Thruster by Eminence and built-in LED power 24" x 11". Volume: pan #019/100T125. Made in USA. Poly foam $24.80 meter. 5"x 2 1/2" 100 1.9 cubic feet. $27.50 watt version available$14.50 surround, 56 oz. magnet. #270-047 (1-9) (10 -up) 2-1/2", 2 layer voice coil. $22.50 $19.95 150 watts RMS, 210 watts #260-235 (1-5) (6 #260-350 -up) (1-3) (4 -up) max. 4 ohm fs = 23.5 Hz, QT5=.33, VAS= 17.9 12" POLY WOOFER PIONEER HORN cu ft. SPL =94.8 dB 1W/ 1M. Net weight 15 lbs. Super duty, 40 oz. magnet. TWEETER 100 watts RMS, 145 watts $43.50 $39,80 Mylar dome. 2.93 oz. #290-180 max. 4 and 8 (1-3) (4 olun compat- barium ferrite magnet. 8 -up) ible (6 ohm). 2" voice coil. ohm. Response: 1800- fs = 25 Hz. QTS= .166, 20000 Hz. 35W RMS, GRILL FRAME KIT VAS= 10.8 cu ft. 50W max. fb=2000 Hz, With this kit you 25-1500 Hz. Net Response: SPL = 106 dB. Pioneer can make speaker weight 9 lbs. Pioneer #AHE60-51F grill frames up to #A3OGU40-51D 30" x 40". Kit includes 4 corner #290-125 $36.80 $34.50 #270-050 $6.50 $5.90 (1-3) (4 -up) (1-9) (10 -up) pieces, 2 "T" brackets, and 7 frame bars. Grill 15 day money bade gu¢ºse 115.00 mncsmn ceder We accept mounting kit Ézpr`éss Maaawsd, Vet, Diecwer, and COD. orders 24 has sléppo,q 'Shipping charge = UPS chan rate '$1 M (13.00 minimum charge) included.

'Hours: 330 am- SAO EST. Monday - Friday 'Mail order 340 E. First St" Dayton Oleo 43402 pm $8.50 $7.80 Local: 1-513-222-0173 customers, please call for shipping estimate on order exceeding #260-333 FAX. 513-222-4644 5 lbs. (1-9) ( 10 -up)

CIRCLE 56 ON FREE INFORMATION CARD 97 www.americanradiohistory.com Mail Order Electronics Worldwide Mail -Order EI ctronic ameco 24 HOUR ORDER HOTLINE ELECTRONICS 415-592-8097 IC Clearance Sale!

NEC V20 & V30 CHIPS MICROPROCESSOR COMPONENTS MISC. COMPONENTS Replace the 8086 or 8088 in Your IBM PC and Z80. Z80A, Z80B. SERIES 8000 SERIES Continued 8000 SERIES Continued TANTALUM CAPACITORS Increase its Speed by up to 30°. price Part No. Pece Part No. Price Par1_No. Part No. Price TM 135116@358 I, 1614 354 7of 6- 35V 45 UPD70108.5 (5MHz) V20 Chip $6:49- $5.95 Z80._... 1 19 8155-2 3.49 8286 _. 2.29 TM1.35 1 a @ 35V 19 TM6.8.356.8p1 @ 35V 49 1 UPD70108-8 (8MHz) V20 Chip 94.49- $7.95 280A 29 81055 3.95 8741. . ..9.96 9.49 7M2.2/352.20f@35V 25 TM10/35 tout @35V. 59 280A-CTC.. 1 65 8156 2.95 8742 4-7.96 14.95 UP070108-10 (10MHz) V20 Chip ..$12.29 $10.95 POTENTIOMETERS UPD70116-8 (8MHz) V30 Chip 6&96- $7.95 Z80A-DART.. 496 3 95 8205 449 8.99 8748 25V) 7.95 1 Values available (Insert ohms Into marked UPD70116-10 (10MHz) V30 Chip ..636.95- $15.49 Z80A-PIO. 4-84 49 82C11 6.95 8748H (HMOS)(21 V) 9.95 space "XX"1 Z80A-SIO/0. 3-96 2.95 8212. _. _ 4444. _ _ ....2.28 1.99 8749. 9.95 50062, 1K, 2K. 5K, 10K, 20K. 50K, 100K, 200K. 1MEG 280B..... _. 2.75 8216 1.39 8751H (3.5-12MHz).. 36.95 43PXX 314 Watt.lSTurn .99 I63PXX 112 Wan.1Tum .89 7400 Z80B-CTC.... 3-96. 3.25 8224 4-46 1.49 8755 1195 Part No 1-9 10± Part No _1 5 -1Q 2808 -PIO 3.95 8228 __ _ 496 1.49 80286-10 (10MHz)LCC 49.95 TRANSISTORS AND DIODES .896 6.95 8237-5 4-26 3.95 80287-3 (5MHz) ...... 109.95 SALE .15 747, . SALE 25 PN2222 .13 PN2907 .13 1N4004 .12 8000 SERIES 8243 1.75 802878 (8MHz) 209.95 29 .19 74ï5 49 2N2222A .29 2N4401 12 1N4148 .07 39 0250A... _..4-96 3.95 80287.10 (10MHz) 259.95 SALE .15 7476 45 35 8031...... __.8:96 349 2N3055 65 1N270 25 1N4735 .29 82508 IFo, IBM) 6:95 4.95 80386-16 PGA 279.95 35 25 7483 4444.. 80C31.____,_....996 8.95 2N3904 .12 1N751 15 C106131 49 69 59 8251A 1.69 80387-16 (16MHz) 395.95 8035... . 4,96 1.25 39 29 7485 _.. SALE .45 8253 1.89 80387-20 (20MHz) 459.95 SWITCHES .25 7486 8039.. 4196 1_59 SALE ..SALE 29 1.95 80387-25 125MHz) 569.95 I 82535.. -408 35 25 7489 1.95 1.85 8052A H BA S C .. ..24.95 JMT123 SPDT On -On 1.19 I 206-8 SPOT. 16.pm DIP 1.25 82053 5 3.95 82284 )8MHz).,..949 795 410 SALE .15 7490 49 80808... 226 1 49 MPC121 SPOT 0,.00-O. 1.19 MS102 SPST. Momentary .39 .39 8254 3.95 82288 (8MHz(. ...996 7.95 SALE 19 7493 45 8085A. _. 2-49 1.95 35 82554-5 2.95 DATA ACQUISITION D -SUB CONNECTORS SALE 25 7495 SALE 29 8085A-2...... 3-59 8087 (5MHz 99.96 82C55A 5 3.49 ADC0804LCN 3.25 SALE .19 74107 SALE 13 94 95 DB25P Male. 25 -pin .69 DB25S Female. 25 -pin .75 80871 (10M -L' 184.95 8259 0 2.25 ADC0808CCN.. 6-96 549 SALE .19 74121. 4444 SALE 25 134 8272 3-95 2 95 ADC0809CCN 3.69 29 19 74123 SALE .35 8087-2 (8M5. 95 LEDS 8088 (5M1-1z 4-95 3 49 8274 5-95 4 95 ADC1205CCJ-1 _._ 1849 SALE 13 74125 SALE .35 XC556R TPN Red . 13 XC556Y T -PN Yellow-. 17 8088218M1 ..99 595 8079 5 295 2 25 DA 08084 CN 4-36 1.49 74147 1.49 XC556G T11 Green 17 XC556C T7 1x CleaxRed 17 SALE .15 SALE 92&2 902 'OLD 495 74150 39 29 SALE 1.10 952'í13A 1.95 SALE 25 74151 SALE .13 IC SOCKETS SALE 29 74154 1.35 1.25 Low Profile Wire Wrop (Gold) Level 02 SALE .59 74161 69 .59 STATIC RAMS 6500/6800 BLP .11 8WW .59 89 79 74173. SALE .59 Part No. Function Price 68000 Series 14LP .12 14WW 65 89 79 74174 SALE .35 16LP 13 16WW 69 2016'2 2048x8 '20ns ...... 295 Part No. Price 1 95 1.85 74175 SALE .35 24LP 25 24WW 119 2102 1024x1 350ns.. .89 39 29 74193 79 69 6402 _.395 3.49 28LP. 27 28WW 139 2112 256x4 450ns MOO .._.__..... 6-49 1_95 6502 2-55 225 40LP 29 40WW 1 89 4506s 74LS 2114N 1024x4 _..,_ __._.99 79 2.6 2.59 solderte,I 5landard,Gold 5 T,,, 6 Meader Plug sockets 4160 4oaIlame 2114N -2L 1024x4 200ns Low Power ...... 1.49 r.t. . 7.75 SALE SALE 21C14 1024x4 200ns (CMOS) ...... 49 h52C 1.95 74HC HI-SPEED CMOS .LSO. SALE .15 74LS151 4_,444 SALE 29 5101 256x4 450ns (CMOS) .. .._.2-49 1.95 6522 295 -4LS0r 6116P-1 2048x8 100ns (16K) ._....396 SALE .15 74LS153... .. SALE 25 CMOS ...... 3.19 65022. 425 Part Nq. Price Part No. Price -4LS04 SALE .19 74LS154 .... ._.,... 1.19 1.09 6116P-3 2048x8 150ns(16K) CMOS ...... _348 2.79 - 6532. ._ 6-49 4.95 45(700 SALE .17 74HC1 75 59 -41505 SALE .19 74LS157 45 35 6116LP-1 2048.8 100ns (16K) LP CMOS.. 4439 3.59 6551.. 296 2.69 4HCO2 SALE .17 74HC221 SALE 69 '4LSOé c .49 74LS161 SALE 6116LP-3 2048x8 150ns (16)() LP CMOS...... 3.96 3.09 650802 (CMOS)19 9514.75 29 74HC04 SALE .17 74HC240... SALE 59 74LSO7 59 .49 74LS163 _.., 6264P-10 8192x8 t00ns 164K1 CMOS._.,...... 9% 9.49 6800.. _ _...... 435 1.49 ..... SALE .35 74HC08 SALE .17 74HC244... 79 54LSOP .18 745S164 SALE .35 6264P-15 8192x8 150ns 164K) CMOS ...... 926 7.49 6802._.__..._.. 2.95 '4HC10 SALE 19 74HC245 SALE 69 '4LS0', SALE .15 74LS165 75 .65 6264LP.10 8192x8 t00ns164K)LP CMOS ...._49;95 1025 6808.... _. _..... 1.95 '4HC14 29 74HC253 SALE 39 74LS10 SALE .15 74LS166. 6264LP. 12 8192x8 120ns (64K) LP 49,49 436 SALE .69 CMOS..,.... 895 6810 .99 74HC30 SALE .19 74HC259_.. 49 :41511 29 19 74LS173.. SALE .35 6264LP45 8192x8 150ns (64K) LP CMOS...... 49.26 7.95 6820 ...... _ .. 2.75 74HC32 SALE 25 74HC273.. SALE 49 74LS14 SALE .29 74LS174. SALE 29 6514 1024x4 350ns CMOS...... 315 6821 436 1.49 74HC74. ... SALE 29 74HC373. 69 -.:i. .15 74LS175... SALE 29 43256.10L 32.768x8 100ns(256K)Low Power .26,96 2395 68B21.. _...... _ 4,95 1.75 520SALE 74HC75. SALE 29 74HC374. SALE 59 SALE 19 74LS191.. 43256-15L 32.76858 150ns(256K)Low 'a :. ...36.26 6840 SALE .39 2295 3.49 2.95 '4HC76. SALE .29 74HC595. 1.29 SALE .19 74LS192_. 59 .59 62256LP,10 32.768x8 10Ons 125661 LP' = 27.96 2495 6845 ...... _._ 2,7ó 2.49 '4HC85__. 55 74HC688 SALE 1 25 SALE .15 74LS193.. 69 .59 5.2255LP 12 32'68x8 120551256KLP-"-- 2:-25 2425 6850...... _....,.. _. _ 4-96 1.49 '4HC86__.. SALE 25 74HC943 SALE 7.95 SALE .19 74LS194. SALE .45 6852 46 .59 4HC123 SALE 49 74HC4040 SALE 79 SALE 25 74LS221.. SALE .49 MC68000L8.... 9-96 8.49 4HC125_._. 49 74HC4049 SALE 25 79 39 74LS240.. SALE 45 MC68000L10... 11 .95, 8.95 RAMS '4HC132 ... SALE 39 74HC4050 89 79 DYNAMIC MC68010L10.. SALE 25 4'.5=: 74LS241. SALE .49 3996 29.95 '4HC138...... 45 421000A99.10 74HC4060 SALE 69 '4LS73... SALE 25 74LS244.... 4444 SALE 49 1.048576, M068020RC128 . 89.95 '4E-10139 ... SALE .35 74HC4511.. SALE 99 '4LS74 __. SALE .19 74LS245 SALE 59 421000A96-10 1.048.576x9 - 15 MC68701. ... ._. 17.95 . ,9 '450154 1 49 74HC4514 -4LS75...... SALE 25 74LS257 .. 4444 SALE 29 421000898-80 1,048.576x9 - -- 4+5-95 22995 MC68705P3S...... 9.95 -19716n, SALE '1. '1,-P SALE 99 -4LS76 39 29 74LS259 .4444._ 421000A98-80 1.048.576.980051MEGx9 SIM _...,239.96 MC687051T3L 49.96 99 .89 22595 949 SALE '4LS83 59 49 74LS273 . 89 .79 1M54416'12 16.384x4 120ns .__...6.76 5.95 MC68705U3S._49,96 949 -.9_585 _4444. 59 49 74LS279 49 TMS4416.15 16.384x4 150es MC68450L 10... 49.95 29.95 39 .._...... 625 5.49 TTL -4LS86 _.. 29 19 74L5367 SALE .29 4116-15 16.384x1 150ns IMM5290N2) _.._.....4.39 1 25 MC68881RC16A...12995 74HCT-CMOS -41590 SALE .29 74LS373.. SALE .59 4128-15 131,072x1 15Ons IP'99yback, .... a9 MC68881RC20A 16995 SALE SALE SALE 29 74LS374. SALE .49 4164.100 65.536x1 10Ons .....349 3 2+ 7460102 SALE '4HC1157 SALE SALE .35 74LS393 SALE 69 4164.120 65536x1 120ns ....396 250 Commodore 7460704 SALE 74HCT174 SALE .25 49 39 74LS541 SALE 99 4164.150 65.536x1 159ns _4.2,69 24_ 7460708..... SALE 15 74HCT175 SALE 25 SALE 29 7415590 595 7 06 4125660 262.1440 60ns...... 426 8.49 74HCT14. 29 74HCT240 SALE 59 513052P_ . ..,6 99 41256-80 262.144x1 80ns .... 7-96 695 7410732 SALE 17 74HCT244 49 6504A .... 1.19 SALE 41256-100 262.144x1 ,OOns...... _._._...... 7,25 7460174 SALE 25 74HC 7245 49 649 6510 14.95 SALE 74S/PROMS" 41256-120 262.144x1 120ns.. 44 44 444__4 .696 6.19 -457186 SALE S ) SALE 15 6526 _ 14.95 41256-150 262144.1 150ns.. 4444. SALE 649 589 6526A 15.95 SALE 4126412 646x4 120ns Video RAM 12.95 SALE -4S'89 6545-1,_. .396 2.95 4146410 65.536x4 1900s 0449 SALE .19 745240. 895 6560._. _. 49-96 8.95 LINEAR 41464-12 65.536x4 120ns 4-96 825 SALE .19 745244. SALE 75 6567...... _ 24.95 TL071CP 41464-15 65.53624 150ns 1495 7.95 SALE 25 745267'. 149 6572 '095 7.95 TL072CP L'0:. . . ,.49 5125810 262.14441 10Ons Slane Coln, __. 43.96 8.95 SALE 1.25 745288' 6581 (120) 12.95 TL074CN _. 4125699A-10 262.144x9 100ns256x9S1P ....44996 99 LM 1496N ...... 69 SALE 49 745373. SALE 99 69.95 6582 (9V)__ 4295 9.95 TL081CP 41256696-10 49 LM1871N 1.95 SALE 25 748374.. SALE 99 262.144x9 100ns 256,49 SIM 7496 64.95 8502_. 7.95 TL082CP 49 1048.57641 LM1872N 1.95 SALE -5 74S387.. 511000P-10 10Ons 11 Meg, X96 15.49 4-96 8564.._...__.... 2.95 TL084CN . .89 ULN2003A ,75 511000P-80 1048.576x1 80ns (1 Me4- --96 21.75 SALE :5 74S472'. SALE 8566 .996 7.95 LM301N .35 XR2206 3.95 514256P-10 262 144x4 100ns I1 Men ---.6 22.95 SALE , 74S5711 8701. . 9.95 LM307N. .39 XR2211 2.95 95 8722.... 4-2-95 8.95 LM308N 59 XR2240 1.49 CD-CMOS EPROMS 82S100PLV' 15.95 LM309K 1.25 26LS29 2.25 325572-01 17.95 LM310N...... __._1.29 26LS31 99 L.1 ` 901225-01 15.95 LM311N .39 26LS32 99 14jí2 .19 004052 ... .. 1MS2532 4096.8 .450ns,25V).. 901226-01 15.95 LM317T .65 26LS33 1.49 D4007 25 CD4053 1M52532A 4096x8 450ns112.5V- --- -5 901227-02_ _.. 4.95 99 ULN2803A 1.19 D4011 .19 C04060 0652564 450ns 901227.03..__ 15.95 LM319N ...-1.29 8192x8 12581 .... _ 95 LM2901N 25 114012 25 LM323K_. .. CD4066 1MS2716 2048x8 450ns 1.5V .5V. -12V1 _.___696 649 1595 349 LM2907N 1.29 D4013 .29 901460-03.... 1 95 LM324N._. _.. 35 CD4069 '702A 256x8 2Kí,os, .. 496 425 LM291714 (8 pin) 1.79 D4015 .49 901436-06.__ 2-95 LM335Z_. _. _. .. 1_39 CD407o 2708 1024x8 450ns .. 5-96 595 04016 LM3362LM33 99 CD4071 .22 2716 2048.8 450ns 125v)...... 9.6 325 -No specs available MC3479P 3.95 04017 .49 82S100PLA -11171C-641 1 09 CD4072 .22 2716, 2048x8 350ns12501 3"96 3 09 MC3486P 1.19 04018 .59 LM3387K.. .449 CD4073 ... 22 27016 2048x8 45pns125V,CMOS 4J6 - MC3487P 99 LM339N.. _...... _. . .. 39 04020 .59 UDN3613M 39 C04081 .22 2732 4096x8 450ns 125V .. LF347N ... D4021 59 74C/CMOS ..149 LM3900N 49 CD4093 .35 2732A-20 4096x8 200ns 12181 M348N...... __ ...... 69 D4024 .45 LM3905N 1.19 CD4094 .89 2732925 4096x8 250ns12181 .. 3.»s _ - -4C-"4 S4 e 39 LF351N .39 D4027 .35 LM3909N 89 CD4503 27C32 4096x8 450ns 1258, CMOS 4-35 75 LF353N 49 D4028 49 39 -4C, Sale 59 LM3914N 1.79 CD4511 .69 2764 20 8192x8 200ns121V, 4 2í LF356N.. ..._ .. .79 J4029 69 '40192 Sale 99 NE5532 69 C04518 75 2764-25 8192x8 250ns 12181 .. 3.59 LF357N.... ._ .. 89 74030 .35 '41,75 o3 e tÿ 740194 Sale 49 NE5534 .69 C04520. _. .75 2764425 8192x8 250nsr12.5V, .369 339 LM358N...... 49 _14040 .65 74010 Sale .15 74C221 _..-.179 7805K (LM340K-51 1.29 CD4522 .79 27C64-15 8192x8 150nsr125V-CMOS 5.95 LM380N .89 J4042 59 74C240 7812K (LM340K-12) 1.29 27'28-20 16.384x8 200ns 215, 74014_.._.....49 Sale 75 LM 386 N - 3 .. .. 89 214043 59 CD4528 69 .649 595 7815K (LM340K-15) 1.29 1 _. .. 27'2825 16.384x8 .. 74032 Sale 19 740244_.... 79 LM393N .39 54046 65 C04538 .79 250ns 12181 .596 495 78051 (LM340T.5) 45 27,288.15 16.384x8 150nsn2551 LF398N .. 195 r.w54 7.75 74C373 Sale 149 78121 (LM340T-12) .45 2728A20 16384x8 LF411CN. .. . 79 .200ns112.5V. 5-26 475 74085..___.1.49 74C374 Sale 149 78151 (LM340T-15) .45 270128-25 16384x8 250ns1215 17306 6-96 LF4120N 1.29 549 74086 Sale 19 740911..-695 _. .. .29 7905K (LM320K-5( 1,35 27256'5 32768x8 150nsn2.5v 8.95 NE555V 74089.. Sae 295 740912...__...795 XRL555 .59 7905T (LM320T-5) 49 27256-20 32768x8 200ns 112.55: .. 626 5.49 .. 75113 1.19 74C9í__. 99 740915 1 19 LM556N. 45 EEPROMS 2725625 32.768x8 250ns 112,581 649 4.95 Sale LM565N .. .89 75150.. ._ _. .. 1.19 270256.15 32768x8 150ns112.5V,CMOS 4-96 725 740151 Sale , 49 740917 Sale 3.95 .Reap Wr,le LM566CN ... 1.19 75154 1 19 270256-25 32768x8 250nsn2.5V,CMOS _549 4.95 740154 Sale 2.75 740920 Sale 395 75174 . Read Wete 5 49 LM567V 75 2.95 275'2-20 65.536x8 200nsi12.58, . ..10.95 -:17A 2048.83500652 Rood 7401575,318125 740921 Sale 2.95 LM723CN .39 75175 2.95 write 795 2751225 65536x8 250ns:12581 _._.. 9.95 7401605418 49 740922. .395 LM741CN .. .29 75176 ....,.... 2.29 564A 8192x825005 5V Read Wete ,, cx 8,13-95 27C51225 65.536x8 250ns 112.581 CMOS . .949 649 740161 Sale 49 740923....._.395 LM747CN .49 75451 39 464830 819248 300ns 5V Read Wnle o. 01112.95 2701024 13' 072x8 200ns 112.5N CMOS n Me4- 2496 19.95 740162 49 LM1458N ...... 35 75452 39 -1158 8192cR 750^.s Read Wete 88754 Sale 740925_ ..549 5V 12 95 8192.8 648450,,250 Cern Enahl, '995 LM1488N .. 45 75492 79 1.. .. ,_ -.= '40926 595 I,.. 1 49 8192.8 DS14C88N (CMOS) 1.19 M["45t-"P 295 PARTIAL LISTING OVER 4000 COMPONENTS AND ACCESSORIES IN STOCK! CALL FOR QUANTITY DISCOUNTS 98 RAM S SUBJECT TO FREQUENT PRICE CHANGES

CIRCLE 114 ON FREE INFORMATION CARD

www.americanradiohistory.com Worldwide Since 1974 ANNIVERSARY QUALITY COMPONENTS COMPE7771VEPRICING 1974 - 1989 PROMPT DELIVERY

TEST EQUIPMENT JAMECO IBM PC/XT 8MHz Turbo PROTOTYPING PRODUCTS GoldStar 20MHz Oscilloscope Compatible Kit With 256K RAM Jameco Solderless Breadboards Free! QAPLUS Diagnostic Software Included! PC Write Word Processing Software Included! NEW 256K RAM Included, Expandable to 640K AMI BIOS ROMs Included JE23 JE24 JE27 4.77 or 8MHz Operation Part Dim. Contact Binding Flip -Top Case w/150 Watt No. L" x W" Points Posts Price Large 6" rectangular display High sensitivity: 1 _ mV/div High accuracy: ±3% Stable, low -drift de- Power Supply JE20 6.5 z .75 200 0 $1.95 sign Distortion -free waveform measurements 360K Disk Drive JE21 3.25 x 2.125 400 0 $4.95 Special TV sync for quick measurements Con- Parallel Printer Port JE22 6.5 x 1.325 630 0 $5.95 JE23 6.5 x 2.125 830 0 $7.95 venient X - Y operation mode 84 -Key Keyboard JE24 6.5 x 3.125 1,360 2 $12.95 GS7020 $399.95 Monochrome Amber Monitor JE25 6.5 x 4.25 1,660 3 $19.95 JE26 6.875 x 5.75 2.390 4 $24.95 Probes 7.25 x 7.5 3,220 4 $34.95 Oscilloscope JE3002 IBM Compatible PC/XT 8MHz Turbo Kt $499.96 $479.95 JE27 Attenuation: x1 / x10 EZDOS MS/PC-DOS Compatible Operating System $49.95 DATAK Photo Etch PCB Kit Capacitance LF180): TrueBASIC Make your own circuit boards! 180pF / 22pF; LF210): EZDOSP Same as above with $69.95 40pF/17pF IBM COMPATIBLE DISPLAY MONITORS The ER4 LF180 Pictured photo etch LF180 40MHz Oscilloscope Probe $19.95 AMBER 12" Amber Mono. $99.95 kit contains LF210 100MHz Oscilloscope Probe $29.95 HD55H la" RGB 640x240 $249.95 all the chemicals neces- TM5154 EGA 14.720x350 ewes $369.95 Metex Digital Multimeters sary for any JE1059 EGA Monitor & Card $649.95 $499.95 Metes General Specs: hobbyist, en- TM5155 14" Multiscan 80005601$649,96 $499.95 Handheld, high accuracy gineer or AC/DC Voltage, AC/DC Cur- QC1478 14" VGA 720x480 $449.95 $399.95 0C1478 student to ' Pictured rent, Resistance, Diodes, JE2055 VGA Monitor 8 Card 9649,96 $599.95 create pro- Contains: Print frame, Continuity, Transistor hFE fessional circuit boards. ranging w/overload JAMECO IBM PC/XT/AT COMPATIBLE CARDS photo copy film, resist developer, etch resist, 2 Manual etchant, film protection copper circuit boards, concentrated JE1050 Monochrome Graphics Card w/Parallel Printer Port (PC/XT/AT) $59.95 developer and fixer, resist patterns and complete M3650/13 M4650 6 only: JE1052 Color Graphics Card w/Parallel Printer Port (PC/XT/AT) $49.95 instructions. Must be shipped ground (surface). Also measures frequency RAM (PC/XT/AT) $159.95 and capacitance JE1 055 EGA Card w/256K Video ER4 Photo Etch PCB Kit $34.95 JE1 071 Multi I/O Card vi/Controller & Monochrome Graphics (PC/XT) $119.95 M4650 only: PC Data Hold Switch JE1060 I/O Card w/Serial, Game, Printer Port & Real Time Clock (PC/XT) $59.95 Jameco Prototype Boards $29.95 Laminated 4.5 Digit M4650 Pictured JE1061 RS232 Serial Half Card (PC/XT) Specs: JE1062 RS232 Serial Halt Card (AT) $34.95 glass epoxy .062" thick M3610 3.5 Digit Multimeter $49.95 2 oz. copper clad with JE1065 I/O Card w/Serial, Game and Parallel Printer Port (AT) $59.95 M3650 3.5 Digit w/Freq. & Capacitance $69.95 solder tin finish. All JE1081 2MB Expanded or Extended Memory Card (zero -K on -board) (AT) $99.95 M365013 Same as M3650 w/Bargraph $79.95 holes are .042" dia. on JE1 041 20/40MB Hard Disk Controller Card (PC/XT) $79.95 .10" x .10" grid pattern. M4650 4.5 Dig. w/Freq., Capacitance JE401 Pictured JE1043 360 K1720K/l.2MB/t.44MB Floppy Disk Controller Card (PC/XT/AT) $49.95 and Data Hold Switch $99.95 JE401 4.5>x6.5" 1 -sided 3 -hole pad pattern $9.95 JE1044 360K Floppy/Hard Disk Controller Card (PC/XT) $129.95 JE403 4.5"x6.5" 1 -sided pwr & gnd busses $9.95 Metex Autoranging Jumbo 1003VMM2 360K,720K'1.2MB/1. 44MB Floppy/Hard Disk Controller Card (AT) $149.95 JE405 4.5-x6.5" 1 -sided general purpose $9.95 Readout DMM JE407 5"x13.25" 2 -sided general purpose $19.95 AC/DC Voltage, AC/DC SEAGATE HALF -HEIGHT HARD DISK DRIVES JE417 a a .e s 01, x- 1 2 card mart board $19.95 Current, Resistance, Diodes, (PC/XT/AT) $224.95 J E421 $19.95 Continuity and Frequency ST225 20MB Drive only ST225XT 20MB w/Controller (PC/XT) $269.95 3.75 Digit (.8" High) ENGINEERING/DATA BOOKS Ruggedized, Water- ST225AT 20MB w/Cortroller (AT) $339.95 resistant case ST238 30MB Drive only (PC/XT/AT) $249.95 21035 Carry Ti L t;oo"o00"',88. $14.95 Easy -to -use pushbutton ST238XT 30MB ',Controller (PC/XT) $299.95 21398 Sams CMOS Cookbook (88) $19.95 switches ST238AT 30MB w Cortroller (AT) $389.95 ST225XT Pictured 22453 Sams Op -Amp Cookbook (88) $21 .95 M80 $59.95 Seagate 40MB and 60MB Hard Disk Drives Also Available! 270645 Intel 8 -bit Controller Hndbk. (89) $19.95 A.R.T. EPROM 270646 Intel 16 -bit Controller Hndbk. (89) $19.95 Programmer IBM PC/XT/AT COMPATIBLE MOTHERBOARDS 270647 Intel 32 -bit Controller Hndbk. (891 $19.95 400041 NSC Linear Data Book Vol. 1 (88) $14.95 Programs all current EPROMs JE1001 4 77 8MHz (PC XT) $89.95 400042 NSC Linear Data Book Vol. 2 (88) .... $9.95 in the 2716 to 27512 range plus JE1002 4.77/10MHz (PC/XT) $4-09,96 $99.95 X2864 EEPROM May be 400043 NSC Linear Data Book Vol. 3 (88) .... $9.95 the JE3005 Baby 8/12MHz (AT) $329.96 $299.95 operated by any RS232 port w/ ICM89 1989 IC Master 3 Volume Ser ... $119.95 JE3010 Baby 8/16MHz NEATIATI$469.45 $399.95 terminal emulation Fully intelligent ASCII command driven JE3020 Baby 16MHz 80386 (AT) $1190.95 $999.95 EDUCATIONAL KITS included JE3025 Baby 20MHz 80385 1A1, $1199.95 Menu driven software JE310l315: Fiber op Full 51 n I $1999.95 JE3025 Pictured EPP $179.95 JE3026 Size 25Mez ei. tics kits demonstrate the principles of fiber SPECIAL! Monochrome Text Card IBM PC/XT/AT COMPATIBLE 3.5"75.25" DISK DRIVES optic system design. Sperry Monochrome Display Adapter 352KU 3 5" 720KB IPC 03 ATI $109.95 Complete step-by- 356KU 3.5" 1 44MB (PC XII AT) $129.95 step instructions, the- IBM PC/XT Compatible JE1020 5.25" 360KB (PC XT AT) Black ....$89.95 ory of operation and Allows for Connection tutorial info. incl. J E1021 5.25" 360KB (°C x T. AT) Beige ....$89.95 between Computer and JE1022 JE2206: Function JE1022 5.25" L2MB (PC XT ATI Beige ....$99.95 Pictured 3E2208 Plclured Monochrome Monitor generator kil provides Use for Text only IBM PC/XT/AT COMPATIBLE INTERNAL MODEMS three basic waveforms: sine, triangle and square Great for Network wave. Frequency range: 1Hz to 100kHz Servers and Dedicated 1200H 1.. Baud Internal Modem w Maerikte Comm Software IPC. x' A I $69.95 JE310 Fiber Optics Experimenter Kit $19.95 Work Stations 2400H 2.1.. 0 300 Baud Internal Modern w/MaxiMde Comm. Shur (PC XI A I ) $129.95 JE315 Advanced Fiber Optics Kit $29.95 TEXT $12.95 External Modems and Pocket -Size Modem Also Available! JE2206 Function Generator Kit $19.95

1355 Shoreway Road $20.00 Minimum Order - U.S. Funds Only 11111.111 Belmont, CA 94002 Order Electronics Waddwide e CA Residents Add 6%, 6.5% or 7% Sales Tax 24 Hour Order Hotline (415) 592-8097 MasterCard j Shipping - Add 5% plus $1.50 Insurance FAX's (415) 592-2503 or (415) 595-2664 (May vary according to weight) Terms: Prices subject to change without notice. Telex 176043 - Ans. Back: Jameco Blmt Mailameco not responsible for typographical errors Dala Sheets - 50c each We are VISA° Send $2.00 Postage for a FREE 1989 CATALOG ELECTRONICS We reserve the right to substitute manufacturers '.989 Jameco Electronics 11/89 Items subject to availability and prior sale. IBM Is a registered trademark of Products pictured may only be representative 'motional Business Machines Complete list of terms/warranties is available upon request 24 -Hour Order Hotline (415) 592-8097 The Following Phone Lines Are Available From 7AM - 5PM P.S.T.: Customer Service (415) 592-8121 Technical Assistance (415) 592-9990 Credit Department (415) 592-9983 All Other Inquiries (415) 592-7108

CIRCLE 114 ON FREE INFORMATION CARD

www.americanradiohistory.com *QUALITY PARTS *DISCOUNT PRICES *FAST SHIPPING ALL ELECTRORICS CORP. 3 to 6 Vdc MOTOR SPECIAL !!! SOLAR CELL 6 VOLT D.C. with GEARBOX NICKEL CADMIUM 4 inch square BATTERY CHARGER 9.5 AMP/HOUR silicon solar Probably designed for childs toy. GEL -CELL cell. Produces Lever selects 2 forward and one 0.3-0.45 volts reverse speed. 1st gear aprox. @ 1500 ma in Elpower# 695 120 rpm/6vdc, direct sunlight 1 6 volt, 9.5 amp/hour Solder together 2nd gear aprox. rechargeable in series or par- `JI 300 rpml6vdc, gel -cell battery. allel for higher 1 Y)1 Reverse aprox. Rayovacf CH -4 4.25" X 2.75" X 5.5". voltage or am 120 rpm/6vdc. Recharges up to four AA, C, D or two 9 volt Quick connect terminals perage. Ideal for use in solar panels, bat 3.35" X 1.75" X 3.25" nickel cadmium rechargeable batteries. CAT# GC -695 tery chargers and solar energy products CAT# SCEL $3.50 each CAT# DCM-10 $6.00 LED charging indicator CAT# UNCC $15.00 each $10.00 each 12 for $108.00 25 for $75.00 WALL LED'S DOOR/WINDOW ALARM AD WIDE BAND AMPLIFIER TRANSFORMERS STANDARD JUMBO NEU UPC1651G. 1200 Mhz @ 3 d,. Protects WARNING e9 Gain: 19db ® f-500 hz. $ volt operation. ALL PLUG DIFFUSED T 1.34 sae doors and Snail package 4mm dia. X 2.5 mm thick DIRECTLY REO CATO LED -1 DEVICE -o CATO UPC -1551 2 for $1.00 INTO 120 VAC 101. 81.50 100 for 813.00 windows Murata Erie I PK3e-4A0 10 for 14.50 1001. 535.00 OUTLET GREEN CATO LED -2 High pitched amen, alarm. Op- 10 for fromift erates on 3 - 20 Vdc 20 no. 1' 6 Vdc@200 ma. CATO DCTX-620 $2.25 52.00. 1001. 517.00 @ N -CHANNEL MOSFET R it 9 VdcEt250 ma. CATI DCTX-925 $2.50 YELLOW CATI LED -3 intruders. high 7/9' dia. P.C. board mount. RF -511 TO -220 w CATO P82-84 12 Vac (B1932 ma CATO AOTX1293 83.50 10 f. $2.00 10010,517.00 Opening of door or window pulls $1.75 each CATO INF 511 18 Vac @ l amp. CATI AC TX -1885 $3.50 FLASHING LED $1.00 each 10 for $9.1X1 h pin from alarm module and triggers with bull in I5 volts. circuitoperates NICKEL-CAD LARGE QUANTITY AVAILABLE Simple installation. Oper- on 5 voltea.. loud buzzer. BATTERIES SWITCHES REO $1.00sach ates on 2 AA batteries (not included). STROBE KIT ITT PUSH BUTTON CATI LEDI 10 59.50 (RECHAROEAEl LE) f. Plastic case is 3.32' X 2.29" X 1.19". ITT MDPL aune.. 3/4 X GREEN $1.00 each SPECIAL!! AAA SIZE CATO LED -403 10 Ivory face. 1/2' gray rectangular f. 59.50 with brushed aluminum Pannonia P-18AAA key cap. S.P.S.T. N.O. BI -POLAR LED CAT# DWA $2.00 each 1.2 voit ar 190 MAh Pull to dose. RATED:0.1 amp switching, 0.25 Lights RED one d'xedion. 5 for $9.00 CATI NCB-AAAX $1.90 each arse carry current. P.C. mount. CATI PB8 GREEN the other. Two bads. 10 f.813.50 100 f. $125.00 Variable rate strobe kit. flashes between 60 to 120 65e each 10 for$6.00 1001.$50.00 CATO LED -I 2 for $1.70 times per minute. WA SOUND AND VIDEO operate on either 6. 12 Vdc 10 POSITION MINI -ROTARY LED HOLDER depending upon how you wire the circuit. Cones Two piece holder. MODULATOR complete with P.C. board and instructions 1or easy Mini ta Ssw36-0N 8 om`s CATO HLED 10 for 65o TM UM1381.1. Designed for essemby. CATO STROBE -1 $7.50 each Mini rotary switch. Non-sh.lkp. use wth T.I. Computers. Can be used 1 deck. 10 positions. .125' dia U SIZE $200el each with video camerae, games or shah X .375' long. .377' behind RELAYS 1.25 volte 500 mAh TELEPHONE COUPLING other audio/video source. Built the panel depth. P.C. pint. 12 VOLT D.C. COIL S.P.D.T. CATI NCB -AA TRANSFORMER in NB swoon enable user to CATI MRS -10 WAS $2.50 NOW $1.50 each Omrons 02E -184P 4 Amp contacts AA SIZE $2.20 each Multi Products International* AI9N-HOlD11 switch from T.V. antenna without 335 ohm bt. WITH SOLDER TABS Primary 600 ohm SPDT PUSHBUTTON disconnection. Operates on channel Sugar cube sae. CATI NCB -SAA Secondary: 600/600 ohm Rated6 are 1843 .61' 1 3.4. Requires 12 Vdc. Hook up X.42 X.44 high. C SIZE $4.25 EACH .77' X.61' X.62 high. Rated Barrps @ 125/250cVa P.C. diagram included. mount with pins on DIP spacing. 1.2 volte 1200 nah 6 pins on .187' centers. Blackplastic pushbutton. CATO AVMOD $5.00 each p.c. CATO RLY787 $1.50 each CATO MCB-C Primary Inductance: Switch body:.02 X .94' X .65'. D SIZE $4.50 each 300 mat min., at 1842, 1 wit. CATO PB -18 $1.65 each 10 for $1.50 each 5 VOLT DC SIP RELAY Gould, Allied Control LIGHT ACTIVATED MOTION 12 volts 1200 noA CATO TCTX-1 $1.25 each 10 for $11.00 CATI NCB -D PUSHBUTTON SWITCH SR-IA.5VDC SENSOR OPTO SENSOR GC/Thornsen* 35-420 SPST-normally l) This device contains a U shaped package with mounting S.P.S.T., normally open SIP reed relay. 95 ohm coil. photocell which sense, open momentary push- [00Olol TRANSISTORS ears. 1/8' opening. 3/4' mounting button switch. Red plastic actuator .57' die. - 2 arty contacts. .9' X .29' X .32 sudden change in ORDER BY PART* hola. CATO OSU4 50e each Chrome bezel .68' diameter. Threaded high. Housing resists fluorocarbon ambient light. Could 10 for $4.50 10010,840.00 bushing mounts In .50' dlam. chassis hob. and Chlorinated commercial solvents. be used as a door PN2222 NPN Rated 3 anp ® 250 Vac. Solder loop terminals. CATO RLY-SIP6 Nunciatot or modified TO -92 5 for 75¢ OPTO ISOLATOR each 10 for CATI PB -20 $1 .00 each $1.00 58.50 to trigger other devices. PN2907 PNP 5 1/2 X 4' X 1'. berates on 6 Vdc. Requkes 4 AA bane on (not included) TO -92 5 for 75e Sigma, 1Á11K WHAT $1.00 WILL BUY 301T1-1281. Signal applied to the Input i 10 AMP SOLID CATO LSMD $5.75 per unit 2N3055 NPN coupled by means of light to isolated photo conductive cell. High 200 ASSORTED /Ami STATE RELAY TO-3 $1.00 each reliability ewtching. 12 toll Input. ELECTROL. 52161 CATO OP -301 81.50 each 1/4 WATT RESISTORS 1/4 WATT RESISTOR KIT MJ2955 1 CONTROL: PNP Bent leads, carbon cony. and carbon IAm. Ideal for the workshop, this A.C. Rated 5.519 10 Vdc TO -3 $1.50 each LINE CORDS 1/4 wan resistor kit contains 10 Black CATO GRES $1.00 per assortment (will operate on 3.32 Vdc). eft., 182, sot pieces each of 42 of the most MJE2955T PNP 200 ASSORTED LOAD: 10 arse 0 240 Vac / - .Cm1 popular values (420 pieces to- 21/4' X 1 3/4' X 7/8' TO -220 75$ each NON POLARIZED PLUG 1/2 WATT RESISTORS la)). Includes a divided box and CATS SSRLY-10B $9.50 each CAT* LCAC 21or 51.00 100 545.00 Bent Inds, carbon camp and carbon film. e parts locator. MJE3055T NPN f. OUANTITYDISCOLIJT POLARIZED PLUG CATO GRABRE $1.00 per assortment TO -220 75¢ each 10 for $85.00 25 for $175.00 VALUES In this kit are: CATO LCP-1 60e each 10O f. $50.00 TIP31 NPN 50 ASSORTED SO for $300.00 1001. $500.00 1 ohm, 10 ohm, 39 ohm R DISC CAPACITORS 47 ohm, 51 ohm, 6B ohm, 100 ohm 130 ohm TO -220 75¢ each 14.7 VOLT TRANSFORMER 150 ohm 160 ohm 220 ohm, 330 ohm, 470 Most are art (p.c. lads). Some to 500 volts ohm, TIP32 PNP Sprite Industries# XENON TUBE 560 ohm 680 ohm, 1K, 1.2K, 1.5K, 2K, 2.2K, CATI GRABDC $1.00 per assortment 2.7K, TO -220 75¢ each CS -510A. 14.7 volt. Vaufip 3K, 4.7K, 5.1K 5.6K, 10K, 15K, 22K, 30K, 33K, 32K, 60 hz, 8.82 Va. 15 VALUES OF 47K, 56K, 68K, 100K, 120K, 150K, 220K, 470K. TIP121 NPN --- I' long Ilashtube prepped with 1.61' high X 1.95- X C- --'I 1 MEG, 5.1 MEG, 10 MEG TO -220 75c each ELECTROLYTICS 3 12' red and black leads. Ideal for 1.4T. Mounting holes on 2.32 centers. The resistors alone would sell for Contains both axial and radiai styles from 1 mid. electronic flash . strobe projects. $21.00. TIP126 PNP CAT# TX -147 $3.00 each CATI GRABCP 81.00 per assortment CATI Complete kit CAT# REKIT-14 $17.00 FLT-3 2 for $1.00 Ta220 75$ each 10 for $27.00 100 for $250.00 ORDER TOLL FREE CALL OR MAIL ORDERS TO: WRITE ALL ELECTRONICS 800-826-5432 INFO: (818)904-0524 FOR OUR P.O. BOX 567 FAX: (818)781-2653 VAN NUYS, DISCOVER FREE CA 91408 MINIMUM ORDER $10.00 QUANTITIES LIMITED TWX-51 01 0101 63 (ALL ELECTRONIC) CATALOG CALIF. ADD SALES TAX

OVER Oa.% 101.126.5422 OUTSIDE THE U.S.A. USA: $3.00 SHIPPING SEND $2.00 POSTAGE FOREIGN ORDERS 4000 INCLUDE FOR A CATALOG!! SUFFICIENT PARTS! SHIPPING. NO C.O.D.

100 CIRCLE 107 ON FREE INFORMATION CARD www.americanradiohistory.com What's New at The "First Source" for the Tinkerer, Teacher, Hobbyist, AMERICAN DESIGN COMPONENTS? Technician, Manufacturer, Engineer e warehouse 60,000 items at 31/2", 20Mb., 1200 -BAUD MODEM ADAM JVC 20Mb INTERNAL American Design Components - HALF - 51/4" TAPE BACK-UP expensive, often hard -to-find com- Operates at 300 HEIGHT & 1200 baud. DISK w/CONTROLLER ponents for sale at a fraction of their Bell 103, original cost! HARD 212A; CCIT- DRIVE DISK V.22 com- Call Toll Free: (800) 776-3700 Gives your Adam fast, ' patible. DRIVE reliable data storage & retrieval. Can hold Built-in up to 160Kb of information. Uses indus- THERE'S NO RISK! MNP. try -standard SS/DDdisks. Connects di- (ST225 Compatible) Internal With our 90 -day warranty, Universal 51/4" mounting. For rectly to your Adam memory console. speaker, error any purchase can be returned for PC/XT/AT compatible computers. Comes w/disk drive power supply, Disk correction. RS -232C cable con- any reason for full credit or refund. Average access time: 62 msec. Manager disk & owners manual. nects unit to your computer. 7 Mfr-Lapine#LT2000. Mfr -Coleco, model 7817. status lights, volume control, AC, HELIUM NEON Item #12830 - New Item #15853 RFE - $179.00 & 2 phone jacks, incl. AC plug & Interface Card Special $175.00 Includes Sysgen LASER Western Digital Controller Card phone wire. (Mfrs' Close Out!) - (#3044-001), manuals & software. 2mW For above drive. Microcom 8X/1200 DATA DRIVE #6641 $19.95 JVC #MTD-520H Item #10150 $89.00 Item #24034 New - $59.95 PRINTER POWER SUPPLY Item #23821 New - $199.00 Delivers Item #6642 $14.95 2mW of 632.8 51/4" FULL -HEIGHT CAMCORDER 12VDC FANS... NM light. Laser head ASCII KEYBOARD Cooling applications: RVs, campers. boats. DISK DRIVE - CASE Item #6643 & associated electronics $19.95 computers 8 of 4) are integrated into a single (IBM° CONTROLLERS (Set electronic equp. compact unit. Ideal for holography Compat) Item #7013 $9.95 RFE Ball bearing, & shows, plastic blades, entertainment applications (light ADAM CASSETTES etc.). Req. 12V @ 1A adaptor. Mfd. in Ger- aluminum Ind. Smart Basic, Buck Rogers & blank housing. many. Dimen.: 15" L x 21/2"H x 21/2"D. cassette. Item #7786 Baker's Dozen air $19.95. Item #22726 New - $175.00 Carry your - 702CFM camcorder & NEW BLANK TAPES Muffin' * 12V Power Supply accessories safely! Item #20868 4 for $10.00 Dim.: 4.T x 1/5' deep (Requires compatible plug.) Will accommodate the following cameras: IMC #4715PL-04W-830 Item #19589 $9.95 Matsushita, Panasonic, GE, Quasar, SMART BASIC PROG. MANUAL 48 TPI, 40 Track, item #23724 New -$14.95 Magnavox, Sylvania, NEC, & Philco. Item#20875 New'- $14.95 14" COLOR MONITOR Double Side/Double Density Lightweight, black molded plastic; shoul- ADAM SOFTWARE SET 21CFM Sprite° (CGA IBM Mfr.- CDC 9409T der strap incl. OA Dim.:1 T W x 111 -Ix 9' - Compatible!) Includes Expertype, Recipe Filer, Smart Dim.: 3.1"x 1.0" thin deep. Mfr Travel Master#TC-1711. Item #7928 $79.00 New - Letters & Forms, and Zaxxon. IMC #311 OPL-04W-820 2 for $150.00 New Item #22909 New - $19.95 Item #21746 New $29.95 Item #23978 New -$9.95 MS DOS / CPM COMPUTER EXTERNAL DISK DRIVE "High Resolution" "Graphics Capability" CHASSIS W/OOWpowersupply (Fan cooled - IBM Compatible! Can be used with ADC's Disk Drive 'Disk drives Capable of running MS/DOS 3.2 Chassis, item #14541, & DS/Quad not ind.) Density Disk Drive, item 01893 256K, expandable (chips Input: (see ad at right). must be hard -wired in). 115/230V, Manufactured for Compis Complete with 15" mono- 50/60 Hertz in Sweden. Operates on 115 accommodate: (automatically chrome monitor (amber), 2 full -height drives; or 230V. Built-in printer out- 1 herd switchable). Resolution: 640 x 240 (RGB- 93-key Swedish keyboard 2 floppy drives; or put (serial or parallel). Hook- drive & 1 floppy drive. Input:115/ 230V, horizontal x vertical). Complete with (most characters are in up diagram included! 50/60 Hz. 0ng. for Burroughs computer. COLA card and IBM interface cables. English). Dim.: 11x8'Hs12"D Built-in stand. Dot pitch: .31. Item #21934 hem #14541 $59.50 Mfr - Hitachi; made for Data General. (Disk drives not includedi) New - $199.00 'Chassis w/One 5-1/4" Item #22475 Uses 1 or 2 DS/Quad (Mane/ac s' closeout - DS/Quad Density 7201( Drive Special Offer... New - $199.00 Density Disk Drives. we cannot accept returns on this item.) Items #14541 + #1893 139.00 COME VISIT OUR NEWLY OPENED RETAIL STORE ór SHOWROOM..- ... WE CARRY A COMPLETE LINE OF COMPUTER át GAMIE EQUIPMENT AND ACCESSORIES PC to PC CONNECTION... PC/XT/AT Compatible High Resolution Electronic Instant Ignition MULTI-ACCESS ENHANCED LAYOUT TTL MONITOR... MICRO TORCH REMOTE CONTROL 101 -KEY KEYBOARD (Open Frame) Hand Held One remote controls your Adjust. Flame TV, VCR & Cable Connects Refillable 1.5811. oz. Converters! 2 PC/XT/AT Butane Gas Tank compatible Can be used in a wide computers range of applications: (more with elect. installations, weld- additional kits). ing, shrink tubing, jewelry Oper- One computer * Membrane & toy repairs, de -freezing ates by acts as a file server; the others) can access disks or * 12 Function Keys pipes, etc. Precise & cont- infrared signals, printers attached to the server. Includes interface * Separate Numerical Cursor rolled N -temp. flame, max: this wireless remote elimin- board, hardware, software, manuals, and tools * LED indicators for Scroll, i300'C/2370°F. Flame adj.:12 to 1-12". ates the need for 2 or 3 boxes. Operates needed for installation. Requires 10 Mb (min.) hard Caps & Number locks 9" - 12 vDc Working time: about 2 hrs. Metal stand in- all major brands of TVs. Easily program- drive, and 384K RAM for the server PC. Mfr - NEC * 1" inclination Foot Stand Green phosphor. Schematic incl. cluded. Dim.: 6-1/411x 1.3/16' diameter. med by setting 2 sets of DIP switches. #3284 -P100 -V003 Mfr. #29079 Audiotronics #900961-11 Mfr - Vulcan#20. Gemini #MAC10 Item #23163 New - $99.00 Item #19680 New - $49.95 Item #17198 New - $19.95 Item #22072 New - $39.95 Item #24055 New - $49.95 DYNAMIC MEMORY BOARD... AMERICAN DESIGN COMPONENTS, 815 FAIRVIEW AVE., P.O. BOX 220, FAIRVIEW, N.J. 07022 MINIMUM Upgrade your computer's memory as ORDER YES! Please send me the following My check or money order is enclosed. 815. your needs grow... items- J hem How Q Charge my credit card. RE -1189 No. Many? Description Price Total 0 Visa Master Card O Amex Card No. PC/XT Exp. Date COMPATIBLE Signature * 0-256Kb memory in 64Kb increments Telephone: Area Code Number * Fully socketed for easy upgrade (IBM parity checking) Total Name Memdisk: Simulates high-speed * disk Shipping & handling: we ship UPS unless Address in RAM memory otherwise specified. Add 10% of Total plus $3. * Allows you to print while using the computer Canadian: $3 plus P.O. cost. Charge only. City * Software included Sales Tax (N.J. residents only, Techmar #MU203010 (w/o RAM) please add 6% of total) State Zip Item #19977 New - $29.95 ORDER TOTAL All inquiries and free catalog requests-call (2011 941-5000. * 64Kb RAM Upgrade Set of 9 chips... Item #19983 $17.50 For all phone orders, call TOLL FREE 800-776.3700. In New Jersey call (201) 941-5000.

CIRCLE 106 ON FREE INFORMATION CARD 101 www.americanradiohistory.com 11111kg1 1-800-344-4539 AK, Puerto Rico - 218-681-6674 Telex - 62827914 FAX - 218-661-3380 TWX - 9103508982 DICI KEY CORP INTEGRATED CIRCUITS INTEGRATED CIRCUITS SILICON TRANSISTORS PANASONIC' SU SERIES DISC CAPACITORS a15255µ 80 80085M 451980 48 1.574101 .12 0179505 63 704355 j7 P55729 26 215136 Miniature Aluminum Electrolytic Capacitors 7408 TTL P4129 1200/IK 74152196 .64 800985 5 45208011 .73 1121480 77 e679206 .83 24888 56 7115 33 21 7115138 6,3/10,20 2.25 74307 .047 tal /25 A Prim 7410283M 78 P #410 1500/15 2.25 1 uf/38 1 81 M 80CB9M 45728011 80 11014586 .54 0118501 .63 488 .10 25134 2 25139 8.3/15,000 P 6211 74311 7452806 ,90 P4131 1900/1K 2.25 7458M 5 82C1µ 98 4528801 1.03 151/962 1.50 6478508 63 P21918 36 7X5135 .3 PN5142 74418 1000/25 .75 74132 2200/IK 2.93 74015 .35 74132635 .42 4577KM .88 1518004 1.95 41119509 .83 PN4911 .38 10/22 78314 21 74419 1500/25 .75 7411300 74133 270/ IK 2.93 74021 .35 74153525 1.17 45288CM .83 151802 1.35 40191410 .63 10/33 78315 .27 P4420 2200/25 .75 1 AMP SILICON RECTIFIES 94134 3300/10 293 74421 74025 .35 14153654N .54 CM05 4528211 .83 2118176 12.30 61179512 .63 10/47 #216 28 13 3300/25 35 P4135 3900/1K 4.46 P4422 74015 35 741538645 .54 454180M .78 151830/1 2.55 6479515 .63 Prt 10/100 78317 33 4]0(1/25 .75 M Prive P4138 4700/16 536 7413 6800/25 .83 74055 .43 7415387M .54 4543KM .90 11618712 3.00 009518 .83 No. P.9 1 101885 1.0011 10/220 7218 Al 16 7 0M 28 1320262 P4137 5600/IK 5,34 #0424 10000/25 .83 7402 .48 741.238801 10 4123806 95 151871N 240 279520 .83 10/330 P831º e9 P8216 2 7410026 .28 164001 50 PIA 0041 .70 5.60 49.0 74138 6600/1K 8.44 P4425 1500/25 .90 7402 .4B 7418373N .88 4124KM .83 LM183M 2.55 6N1BM24 .63 10/470 P833 .53 P8217 71X0015 .28 16402 103P1 D0.41 .75 6.0 52.0 741313 820/1K 8.44 74426 2200/25 .94 14086 .43 741537411 .88 LM1815T 525 10/1,00 2321 .73 P62 8 74710080 .28 M6NW5 12403 200 Ply 00.41 .0 6.40 56.0 74140 10000/114 8 44 2427 33000/25 94 7100: A3 7415077M 1.44 LI85MC 16418896 2.16 P6322 .99 12219 7 28 124004 403 Ply ... 00-41 .85 6.80 69.0 P4181 1000/0 .86 74139 4720/25 1.55 7410M .43 815951 1.81 1M L52K12 1.5U 10/4,7fß P8323 1.16 74 CI .28 Pan Prim M PXY 164005 fi00Plc 0041 .88 7.0 81.25 94102 2200/50 .94 74429 88000/3 1.73 74Iµ .50 81159846 1.89 10/4,700 P8324 1.49 2221 1462146 .39 L31]N 1.30 Era1M201N .60 5521476 11,50 12406 00 PIV 00.41 .98 7.0 225 4163 4700/0 1.01 7440 10000/75 131 74Iµ .35 8159112 1.88 10/6,80 P6325 1,96 P6222 7470236 28 1F351N .60 .60 MM525]M 3.40 12407 100 PiV 13041 1.5 8.0 75,3 4184 10000/0 1.13 74431 1000/50 .66 8113885 1.89 10/10,20 12325 2.2 31 74175 35 14X0276 LM2903N .57 118212 28 L7353M 1.05 74C20M 9.37 10/15,00 78327 3.79 850/50 60 94432 150/80 .88 170554 114280411 5% CARBON FILM RESISTORS 422 .68 74300111 7440304 28 720 .51 7408112 6.87 100/10 P4401 220/60 .86 )460 32011 5 1735811 120 082902 3.80 Available m 1.8, 1,4 & 11 Wan 4202 1500/13 .68 P4434 P01 7475432M ,28 7451884 1,70 18/22 P833 .27 330/50 .6 7427M .43 Prim LM2801M 7.80 420 223/13 .79 P4435 74042M .72 173518 I.50 145182 1.10 Take 18/33 P6330 26 470/0 .88 74312 745000 .35 16290758 2.IU Now To Order any standard resistor value /7.e. 420 .79 P4436 30 74X0735 .38 182811 3.38 748287M 16/47 7231 .33 MM/10 20/0 .94 71502M 20 3.21 and add en "5" for 1 /8 wan or a for 1/4 74325 35 35 7 1528112 225 "0" wan 4208 4Rµ10 1.0 4M .38 12110M 185 75828811 1.70 16/180 P83.32 .3 P4137 100/0 1.01 7437M .40 74503N .36 1M2817MB 2.25 or n'8" for 1/2 wett (i.e. 3.24 for 3.21 7/4 wett). P4214 880y/10 71 P4438 1500/60 1.07 74X[756 .38 114110M 1.14 1452892 16/220 P6333 .47 12222 74Jµ .40 1/04M .35 LM282µ 2.81 2.10 54/8 M the oigo Key pen number. 4300 02 56 P445 2200/50 109 744C7µ .50 17NIM 85 7153812 1.95 18/330 PW34 .63 2229 744011 7430511 .35 Fµ .0 2203 .64 74440 1,73 48 74 C85 .85 1744401 180 15393125.0 .88 PrICY85 6 WO 1.000 18/470 76335 .83 16130 P1//3 33000/0 74508N .35 1/94122 4,80 4306 .033 xl/26 64 P4441 1.73 74425 .55 74X0880 .15 L113741M .18 15221750 .85 1/5 Watt .25 8.40 25.00 18/100 176334 .82 4700/50 745092 38 7451732 4.80 74450 .98 74401014 ,53 15101M 16293101 185 16/2,20 P8337 1.13 76 715106 770 14547440 1.80 1/4 Wan ,2 3.40 13,0 2 PIPO NPO PIPO NPO NPO NPO NPO NPO 74454M .98 .38 LM7ION 255 1530421 105 18/3.300 78338 1.49 P6ä3 1,2 745116 74 112 53 7/547545 4.80 1/2 wen .3 3.0 15.0 7447411 1.20 .38 1.53422 8.00 118 18/4,70 183339 1.75 1122113M 53 1143006 74157011 3.75 78234 1.n 4400 1.13 7450N 42 7451µ .50 1530889 .84 1/8 Wad Reelable Aaeoau544088 76340 10/50 .68 7445 56/50 7420123x 28 183502 6,00 745511X 3.15 18/8,80 2.14 2235 2.31 74510 74520M .38 2.55 4402 15/50 .79 74410 68/50 1.26 .48 14601255 .41 1143114M .51 213082 7427711 R8112 Set of 5 each of the 73 aun0ard 5% .. $8.00 16/10,00 21341 4.04 745261 .51 4.50 440 18/50 A 74411 82/00 1.91 7453M .34 75 1313301/1 .99 745573M 1/8 wett carbon film resistors in Me 7453µ 48 741101256 .53 1M307N 4,50 4404 22/500 .79 P4412 10/50 1,91 745911 .30 7440133M 153084 .B0 21330211 .98 Mrou 25/10 P6343 .21 74032M 48 .38 4105 27/800 .79 #4413 120/50 1.81 7482 .34 7460136M 1.5312 .54 1.0 me9ohm 1356 tool 2/22 P6344 .26 745400 48 .15 4406 33/60 .99 24414 150/50 2.03 74739 48 11,13402M3514N ]125 NM.53171 25/33 P8345 .3 74XC139N 45 485 -I. 4407 39/50 .98 P4416 180/50 2.70 145514 747µ 48 45 1531712 ,92 1M390pM .88 25/47 96346 .34 7622 745640 74X21474 .73 M 882121/8 of carbon 72aunderd5%.. X80 7442 47/50 1,13 MI8 120/500 270 747µ .50 45 1M305M 180 P2191.531712.88 25/10 76347 .42 78239 145656 ,55 74 0151M .55 0074026 175 1/B wen 3 Blm 10 in the 26/23 P8348 49 767µ .48 741101535 .55 1143177 .99 1.5395911 1.50 74514M 43 2074701 113 1.1.series 1.3, 1.6, 2.0. 2.4. etc., TANTALUM CAPACITORS 741511 .70 1537811 1.65 10381111 2.25 000486M 25/330 76349 .57 P82a 745860 45 74601546 1.13 5.38 5046486 910 Mlohm 13015151 pools). 25/470 7456N 48 1039146 2,85 7630 .86 76242 748C157M .63 513196 1.50 78351 89 76243 P.O C.µ/Voll. Prlu 2045 2.2/25 748µ 7.50 74511111 50 1/4 Wan Roams 12.50011.8/7. 3/1,000 74H015µ 83 1Y3201ì58 .72 76352 1.35 No. NrR/DC 1 #2045 7451135 .50 1111 1.65 Ó827N 3.11 36 P8204 33/3 Â2 74Bµ .55 746018µ 58 1MJ10L211 60 311761 11613 73 74011µ 82 OPB21µ 7.75 Set 015 each of the standard 5% 16.85 35í3.3f5 #6353 1 71 P8245 72011 4.7/6.3 .31 71047 4.7/25 7493µ .56 1.53205.15 .72 1578105402 ./8 7431334 .45 7401616 83 078122 3.75 1/4 wen carbon Ihm reºúors in the 3/4,70 78354 2.55 713246 2 23112 8.8/8.3 .34 1:21)48 28/25 74955 .83 15320575 2.15 278112407 54 74513µ 71 74X01622 .83 022213/1 225 3/6,80 78355 3.79 P2013 10/8.3 .42 72049 10/3 1.0 74102 .53 1610115402 54 71221834 .83 1531067.17 1 90 745135M 1.12 0781289 688 through 1.0 megohm 1365 total 72014 15/6.3 .50 7200 15/3 1.19 747005 53 741101640 .83 1M320W-15 1.85 1M79052T .9] 72151 7151380 .BB OPB138N 6.BB panel. Z/4.7 P 6ä7 .27 76247 P2015 22/8.3 .60 22/3 1.88 741210 .80 74114165M .83 LM372M 2.10 15791221 .96 #2018 72 72062 31/3 7451360 85 0753004 B.B7 RODS Set of 5 each the 72 standard ä/10 76358 .3 123248 33/8.3 2 153731 8.15 157815CT .88 of 5% .. Ni 741230 56 74901740 00830369 35/22 P 8354 .26 72011 47/8.3 .85 P2063 0.1/36 .27 745140M .58 .58 3.13 1/4 wan carbon film resistors in the 76249 1n12µ 80 7460775M .58 1M324M .51 1M1380N 1.80 P630 .35 P6250 72018 2/6.3 1.18 72061 0.16135 .27 7451516 .85 0082718N 1.88 36/33 741325 75 7401835 .78 1M32µ 5.1i 151360 1.44 0p93074M 36/47 P 6161 .42 P2019 10/8.3 1.9 77056 0.22/35 74515311 .85 3.25 through 910 4406m 130107.1 pieces/. 741458 1.03 8.00 1.20 0093366 35/10 P8ä2 .46 72020 .27 7451575 .85 74x07544 .78 LM]Iµ Mel' 2.14 10/8.3 3.60 72558 0.33/35 141480 1.10 1M3271 338 4N7805 .75 35/227 #8363 .56 76253 7394 220/8.3 7.85 7257 047135 14515µ .85 74X01956 .78 M83112 588 1/2 Wad Redeem A..s.640 sIo 27 741506 1.58 7402215 1.10 1.532802 .81 27806 .15 ä/333 76364 88 76254 72035 30/63 116 #056 0.88/35 .3 745181M 2.38 078312 5.813 R8180 Set of 5 each of the 73 standard 6%. 7415Iµ .2 1633111 525 457807 .75 Na ä/47o P 5385 .72 25255 P2022 2.2/10 .3 P2059 1,0/35 .31 74518311 74102406 ,75 111580352.6 3.50 1/2 wen faro 238 00808 .75 6580351411 carbon r5581076 in 750 ä/1,O0 2366 103 116256 72023 3.3/10 .31 72060 1.5/35 34 741534 .63 74517µ 7462415 .75 1143347 1.85 3.38 711515 83 ä/2,200 76367 1.71 71024 4.7/10 .34 22861 2.2136 42 1.508 745175N .83 741102425 ,78 153557 2.10 27809.]5 M5803561 3.25 through 1.0 mepohma 1366 total 35/3,30 # 6088 2.24 982587 2 P2025 6.8110 .42 7222 3.3/35 .51 74155M . 1.20 7452435 .78 1033527.5 27810 .75 165603511 5.63 141575 .60 7451418 2.18 53382.5.0 1.20 pieces). 35/4,70 116369 347 72626 10/10 .0 7383 4.7/35 .85 7 244 .75 657812 .15 IN2154N I].50 7451820 1.75 Set 72027 15/10 .0 72064 6.8/ä 74I81µ .75 74 215 .82 1M311M 1.85 1815 .75 ß82 W of 5 each of the the Ni 7421860 130 8P176:72411217057 46N7818 5 ,75 871352 2500 1/2 wan ,carbonfilm resistors in 50/0.47 72078 22/10 .72 #386 10/36 1.19 7118µ .75 7416 51 .80 L532)W 1.60 MMSSIBIAM1053 the 7422411 I43 AN)820 ,75 0/1,0 2029 33/10 .85 7386 15/38 10M 74t6µ 74X[25315 .85 153371 195 series 19, 13, 1.6, 0. m .90 74512511 113 55581746010.25 0/2.2 7330 47/10 1.18 7399 .047/35 74NC251 83 153388 1920 µ78l01 A7 Ihro h 910 kibhm 13601st -1 '- aal. N6800N 18.35 50/3.3 P8371 .21 P231 68/10 1.82 #210 .28/35 745245 1.63 1M33µ .51 µ78L05 .43 74170 1.63 74n015µ .75 57' 50/4.7 P83n .26 72032 10/10 380 72101 22/36 2.56 7452415 1.83 12134080.5 22 411781.054i 20001 9.25 WIREWOUND REC. RESISTORS 741750 .83 7µ0268µ 38 2.25 0/10 P63]3 762134 601L04F7 7202 4.46 7402430 3.50 1M3408C 17 i.10 µ78107 43 0633111 vn:x In m5K 10 Wen 3 74185 ,90 7µ008µ 90 50/22 P8374 P6265 22 7228474!/72083 P215 47/35 74574411 1.83 15340E2.15 2.10 27808 43 ä 741816 2.50 1µ6288M 135 Take any standard resinor 80/33 P633 A1 7266 73033 1.5/16 .23 #2081 0,1/0 .3 7452512 1.05 234075 .87 4678158 How To Order: vals lie. 741820 1.15 1µ0354M 1.10 .43 NO & DA 0/47 P8378 .45 P6267 2 7204 2.2/16 .31 2088 0.15/50 .30 1452539 10 1143107 12 .87 0178110 43 7.51 and add "4056 for 5 wan, or add a "0127 for 10 741840 345 1452576 130 7463581 1.10 P01 Prim was lie. 7.505 for 7.54 5 watt/. this is the Dpi -Ney 0/10 P8371 .49 7325 3.3/18 .33 72009 0.22/50 .30 741135µ 3.37 74603855 .78 153/0715 ,19 41178112 43 783713 '.70 P6265 2036 4.7/18 .41 72210 0.33/50 10 74515811 90 402032 1.38 pan number. 0/23 741915 1534175 .90 4416115 A3 76379 76270 90 7452812 1.88 14603666 .78 50/330 .3 71037 8.8/16 .50 2071 0.47/60 .33 15341712 100 008118 Ai P 1 10 1,085 741Bµ .90 ItX2362 78 eking 1* NO 0/470 12380 .96 76271 7208 10/16 .0 72072 0.86/60 .37 14528311 1.63 15341715 80 6578120 A0060512 5.00 7118411 ]471[3689 .78 43 5 Wan .38 3.25 260 10.0 162.50 0/1,00 7691 l.ä 76272 7209 15/18 .74 7203 1.0/50 .0 0 7452876 2.00 L534µ 1.65 ÁM78124 43 660859005 5.13 74197M 1.05 14 73/1 75 4000609005 10 Wan .41 3.77 31.0 116.0 212.0 0/2,23 #692 2.52 12273 2 112040 22/16 .56 72074 1.5/0 54 74522811 1.70 µ78M05 8J 8.15 742510 1.11 74 0314 .75 1034µ 80 0/3.30 7632 3.83 12041 35/18 1.18 72075 2.2/50 .0 7453738 1,75 16319M 135 6678506 83 46008186218.50 6 Wed Metal Bedew Aaaaanento 7416511 .85 1477C39µ 10 72042 47/18 1.82 2203 3.3/50 1.48 /453148 1.75 1613568 7.50 41118551 .63 500081700111.15 92013 72077 4.7/0 1.89 5 values 0.302 to . 820.10 63/0.47 78385 21 2/16 3.60 742711 10 74170393M .70 R810 esh of 0.914... 745387M 1.95 11,1352 485 6878508 83 40583312 5.0 2/1.0 #6986 21 72086 10/18 9.5 7328 6.8/0 3.0 743865 70 425331 38 130 total Meal 12472M 4,80 11435811 .51 2781209 .83 40100100432.0 83/2.2 23387 21 7386 10/18 890 72104 10/50 6.40 7545µ 70 7440534M ,56 118206 4400601 valsa 1.00 to 9.112 831.0 7434730 1.60 153599 240 6618510 .63 4035116M925 63/3.3 12328 26 7205 1.5/3 31 1253 15/0 8,37 75451M .50 384101.1 paces) 7454745 4.80 7405815 1.53 2138011 1.50 01181112 83 600371200 825 63/4.7 7632 3 f8218 7545211 .50 74X05766 1.13 ß823 4 each of velues 10 to 914 821.20 74S47µ 180 1538008 150 276015 .83 400301006 888 83/10 76390 34 PANASONIC V SERIES 74453M .50 74605405 1.15 OM total paces/ 743570/1 3.75 1532111 2.61 21851863 403701CCMB.88 0/22 76391 2 76280 .,r.,r.4rvd Metalued Film Cayacitu.: 7545µ 50 74608436 1.75 4 1004 149571: 3 15 11138211 1.86 4618570 fi] 09008001011 1.85 118405 each of velues to 2,054 I01.20 63/ 76392 .47 P62B1 754910 100 7455726 4.50 14X08888 .88 1288 tole) pieces/ 83/47 7693 47 153832 4.05 008524 .93 04008011011 1.58 /0011. Prick 74535 4.83 754920 1.12 7455738 5.20 74204002N .28 63/10 7094 .56 76283 M 0.68/0 1531211 2.55 44105 .75 0400808104 1.65 10 Wan Real.0r A.er4n66rb No. /VAC 10 #4638 0.82/0 574 151836 1.38 74S84µ 7411C402µ .83 061958 75 011208301.26.90 63/220 7295 78 7604 352 116782111 BI 4513 0.01/0 123 74537 10/0 8.62 754125 1,38 7458414 74104040M .93 06COB32lCX ].88 8110 2 each of NI 10 watt standard motor 18886 # 698 .92 3.50 16381M 185 eM7907 .IS 4514 0.012/50 1.26 P4713 0.01/100 1.81 744040486 .70 MC10201CN velues listed in the Oigi-Key catalog. 63/4ro 12267 1.12 16286 1 741500 TTL 153890 1.38 µ1908 .75 I.50 4515 0,016/0 1.28 94714 0.012/10 1.38 74300 74X20506 70 MC10221CM 5.15 65/1,00 16398 1.3 76287 1 1M3B12 1.32 Á47909 .]5 4518 0 018/50 1.32 P4716 0.015/10 1.81 M Prior cros 74X040606 1.63 #698 3.0 1.10 1M791N-80 3.58 5s',, METAL OXIDE FILM RESISTORS 4517 0.032/0 1.35 P4716 0.018/10 1,81 7413006 32 74X040755 28 ÿ361 5145389 5N 1.63 M Pd66 15392.100 2 40 .15 4518 138 04717 052/10 1.85 741026 .32 Available in 1 & 2 Wen 10/0.47 #8101 .21 11622 0.027/0 740051 765040786 .30 153826 .75 42915 75 4519 1.41 P4718 0.027/100 1.86 74110311 .32 45 10/1.0 21402 .21 12289 0.033/0 74402M 45 4x04306 1.44 1143936 .51 641918 .75 586461.12 Bow To Order Take any standard 450510, value (Le. 4520 0.08/50 1.44 P4719 0.1333/10 1.93 74l50µ .31 10/2.2 76403 .26 78260 140044 .18 1µC451µ 150 163857 3.40 27920 1.510 end add a'W I" for I watt, or add a "22" for 2 79521 0.017/0 1 47 #0720 0.038/10 1.96 74L0µ .32 Prim 10/3.3 76000 .3 76291 7403811 .45 )µ04538M 1.05 1M395í 300 116792475 M an 11.e. 1.51(W1 for 1.504 1 want. the is the Dips 100/47 76405 34 1622 0.056/0 1.54 P4721 0.04/10 2.03 74I80µ .32 6979104 .43 051468N .85 7421011 45 7422454376 1.37 163951 10.50 Key 1.n number. 124126 #963 0.221/0 163 2723 0050/10 210 741E0µ .32 0514221 110 10/10 .42 76108 .33 WNW 21.00 11619105 .43 100/22 76407 48 4524 0.002/0 1.3 7470 0.02/10 2.3 3515 .32 4000 CM05 051489N .85 N ó685 1 6 140 NO 1.08 7834 742212 45 165550.75 1279108 43 100/33 76408 .M 1235 453 0.1/50 1.69 P4724 0,09/10 2.3 7415115 ,32 1 Watt 740312 45 M Prim 1.1258011 .0 4679101 .43 754504 .87 150/47 7840 57 4528 0 17/0 1 ® #4726 61/10 2.30 747513 .32 .10 .21 ,56 12.60 56.00 10150 #4728 7423211 48 400180M .17 155852 1.85 009108.43 754514 7º.472.91ºI 10/10 PM10 .62 #837 81 4627 0.15/50 1.96 0.12/160 2.57 74S1µ .45 154522 .70 1 Wan 453 #4717 015/100 275 14083N 1.05 4007KM 10 1658501 1 58 46791.0943 10/220 P 6/11 1,21 1 rI 0.18/0 2 01 741315M 2838 2 74C4µ 1.33 4068[5 83 1558706 1.11 017910 MO-1.0MffiM .15 .70 9.60 40.0 72.0 100/330 2412 1,54 2839 463 0.22/50 2.10 74728 0.18/10 2.3 74132011 .32 43 54165 33 460 2.46 5413 0.22/10 3.94 74073M .85 40075 .28 1.510906N .75 457611127 2 Wan 700/470 76013 2.02 2332 1 :e 0.27/0 7413215 .32 74C7µ .83 40080M .55 111723011 .75 4X161A2.7.131.111.5 .43 76181M 1.00 /0.47.0.9101 .23 1.0 13.15 0.40 10.40 463.1__033/50 2 3 #470 0.27/10 3.34 74S2µ .32 N)BLIB15 .43 75482M 1.12 4532 0.39/0 3.10 7431 0.39/10 3.81 142786 15 /00906 .35 2172505]250X 7.70 2 Wan 10/0.47 1 741.2711 .32 75493M 1.37 74831 74732 0,3/100 4.22 740835 1.80 40121 .3B 1.573329 84 01791.2043 11.01.00421 ,18 10.50 47.60 87.50 180/1.0 0.47/50 3.46 754940 1.3) .6 4634 414 #4731 07/100 741530 .32 740851 1.0 401 BC .28 15141M .51 0X19121 17 160/2.2 12417 0.56/0 4 71 1 Wan NNW 7253211 32 74088M .28 40128CN .28 Real.o10.umrrrN 160/3.3 715418 7253711 .33 14Ú6N 500 4073809 .30 SILICON TRANSISTORS 118101 58616 of 01l77w0,474 to 564 108.98 160/47 76419 PANASONIC R SERIES 7415385 33 140004 13 4014805 .70 1255 total dermal 160/10 25178 8660.8 Par 2x5416 200 2153363 741142M 60 140935 123 4015206 .55 .21 5 0211. 16 160/22 23179 Me Prim 1X5457 60 118201 each of values 624 to 7.554 74185154 45 110959 1.50 4016805 30 hi MPS 65 23 160/33 P6180 M ad. Prlo 0027/50 1.06 1255 10161 Pisces} 741.5561 .38 1.31 2X5550 .35 P 38 160/47 /V/VAC 740101M .85 4077605 .70 1M3111 76181 Ne. /0 003/0 1.05 2X5079 2.55 WS3637A .30 88851 5 each of values 8.212 to 1.05 0.85 7257345 .42 14215011 388 4016809 .70 3M3055 1.17 160/12 12162 #4561 .001/50 1.5 069/0 1.0 2x5680 2.50 M23646 .52 1256 toted Diesel 74L574µ 42 72152 2,60 4012C 35 #4662 .01212 1.0 4559 0047/50 1.05 1.40 2557161 280 MPS 704 27 250/1.0 765791 42 740154M 3.98 10006 0 2M3440 2 Wen Re.Orar Amer.*. 76184 7459 .0016/50 1.0 4E60 058/0 1.0 2M3100 1.00 X5882 2.80 P55171 23 250/2.2 12186 4 74137811 .51 748153 2.80 4021BC values 504 74612 .0018/50 1.05 x5769 32 X55551 65 1315 5 each of 0.47º to 8óJ6 280/3.3 93724 136 12186 #4656 1 745w3µ ,88 1401612 .B3 40128C 5 Pieces) ,0022/0 05 #8006/50100 1M3903 .23 X5771 125 X5655 24 /25610791 250/4.7 26187 741582 .86 7441810 .63 40238C 5112 31 026515 .28 R11202 5 each oI valus 622 to 7.5102 QOM í0/10 #8188 61 a186µ 29 74218211 83 4024805 2M3904 23 5630 J5 75 24 1255 00701 5,0661 250/22 12169 .8 QUARTZ CRYSTALS 7425905 ,51 740763M 83 40258CN 263905 .14 RPM IN3908 .23 5831 70 256560 .41 29625 etch of velus 8.25ºto 1.05 IOIi 250/33 P6190 741095 .51 74C7945 1.23 401780M maim 2M39ú2 1.16 5833 75 X256561 .45 250/47 78191 1 74510721 .48 402880M DH 1401854 1,23 204030 1.12 61 X2912 A5 M Part No. C..e 1 10 7451092 45 74073N 80 402621 6775 35 1°/% METAL OXIDE FILM RESISTORS 2114032 1 12 22015 27 40/1.0 P810 .4 1.00 0046 H433 10.08 44.0 74511245 45 740174M .55 402065 314033 1,24 5725 49 575412 52 40/2.2 191 1.000 0068 144-18 9.86 79.60 7451228 .88 7421755 .55 40312 15038 I40 6117 35 073413 32 460/3.3 P786196 1.8432 0046 HC.33 3.96 33,60 7/151234 ,81 403460M 1 7401826 1.10 I 03 1.40 697 1,30 575414 30 How To Order. Ta4a any standard rade., were 1i. e. 40/4.7 12196 1.6432 X087 7114-18 3.42 28.50 74151252 .18 7401030 1.10 403505 25123 23 257186 1 IS PSA42 A 1.5667/ and add an "X" lie. 1.696X1. this e the D'6í 460/10 78197 2,00 001 HC -33 3.79 31.50 7451213AM .60 7401955 78 40408C 2X3124 .3 X11324 204 M5Á43 45 Key pen number. 450/22 78198 1.6 2000 003 84-15 374 7700 1415132M 7402211 1.50 .83 40410M 284125 .23 X1613 92 275422 A5 6 W8 1.03 2.4678 0047 114-33 3.3 31.50 741S132 4042404 X1803 1.14 .54 140245 1.88 764 X75463 45 2.4576 9065 44-18 25 1/4 Wen 50 7.0 30.60 DISC CAPACITORS 3.0 5.0 7415138N 54 1402448 1.98 404305 4208 1.25 2X2218 95 59551 .36 7 500 X00 HC -18 142 7q N) 74L513µ 80 7403739 2.23 4044026 1.10 25221842218 84 27727 .24 1/4 Watt NNW RN RaaYes A660Mtartn Ot51 X018 15308 Part P4158 10000/0 1.24 6433 3.3 31,50 74215111 .51 74U7µ 2.23 404µ0M 2.10 MÌ51 32788 0022 #4.78 14.40 2X34 801X 5 a of values 1044081.8º 824i No. IPfl/ W . PÑ #4156 16000/50 1.35 1.73 74151536 .57 7406014 .55 604780M 75235 2.0 2X22194 .78 221 13 3.579546 000 4C-33 2.34 19.50 140 mal Pew) #4000 10/500 71 &13.131L_22221.21_135 741.51540 1.44 7409329 .55 4206806 2.30 7M77]1 BO 22248 25 1579048 0948 8C-18 t e 254236 1191( 566ch of values 10429764 8ó.W 74002 16/00 .M 12100 100/500 .68 1t r0 741.315511 80 1409035 35 40490 5237 230 zx2221A .80 P923694 25 3.836 0071 H0-18 140 oral Pieces/ # 403 18/00 .84 #4102 150/500 .68 1.87 13.0 741115811 57 7290411 .55 4050621 5238 735 292222 60 22484 .30 1 710 0017 11r 8/11 240 5eac of values #404 22/500 .64 7415 180/500 68 74151576 .54 7425059 8.25 1057808 04239 2.30 2M22224 .60 2307 23 R0X 1.024 ío9.324 53.6 4.00 X05 HC16 1.9 13.50 2X2380 74026 27/00 .M 74104 220/560 8B 7451588 .54 7406058 55 40528854 5400 .3 60 PN 9011 2PN 1480 07010144661 40320 HC 7400 33/50 .M #0105 270/600 .68 272 -18 1.82 13.0 7451871N 114401 23 2X23894 .80 251 9 5540 5eac of values 10.241097.664 528.116 4.19494 0007 89 740607N 55 40530M 4007 .12 7412 31/500 88 12-18 1.55 13.0 242405 1,45 PN3585 .25 /480 9/50 91520 745183M .89 7409089 1.33 4560609 5102 23 otl pieces/ 400 #4107 4 0050 12.18 182 53,50 2N2409 84 763586 31 47/500 .M äO/60 2 74131601 .85 74290911 245 4086KM X4403 23 O 60 5eac o values 1052to1.0MO 42186 400 56/500 .M 74108 470/50 .75 6.00 801 HG 18 1.62 13.50 41 38 2x2904 .95 23567 28 5.016 0062 745I89N 1.23 7429104 8.88 4071806 .18 4010 56/50 .71 #015 560/60 .3 #4.16 1.62 13,0 948960896 2.90 2M29046 .95 23566 .14 5.1850 74517µ 57 7428110 10.15 4072208 .50 4011 82/50 71 #4110 60/500 79 000 114-18 1.62 13.50 85086 .28 2M2905 16 23639 .30 PANASONIC SU SERIES 7451755 .57 7409129 10.45 107366 .28 4141 100/3 .98 74111 826/500 .79 5.924 0.073 11C-18 1.62 13.50 65087 .28 2X29054 .78 953640 30 8.200 72519011 .81 140614M .95 407564 .26 Mint eeeee Aluminum Electrolytic Capacito 4142 150/3 .98 74112 100/00 .94 003 HG18 1.9 1350 45088 .28 2906 80 23841 .30 6.744 254 5C.16 1.62 13.50 7413181N .81 74091511 1.83 108166 .28 4143 7200/3 96 74114 150/50 M X5089 .29 1 N29086 BD 23X3 .23 Aael Lead Recital Lard 7.372 274 HC -18 1.82 13.0 74151938 .91 7429118 10.45 40828 28 4144 3300/26 .98 #4116 100/11( 1.3 X5210 .28 2N2907 .80 .32 W6/Cep 0195-085 Price 212E12y eke 0058 -113 7446126 1.80 2364 4145 470/3 1.5 74117 120/1K 1.3 8.02 HC 1.82 13.50 741519561 .78 408969 1.0 2N28014 .80 IVDCl/IPI Pen No. 1 Poet No I N5724 21 23125 31 74118 160/1K 9.2160 X075 710-18 1.62 13.50 1415222 .93 740922M 4.23 40936M .0 .90 34 4148 600/25 1.5 1.3 X5275 .23 I 313 24127 6 3/47 25 1.13 #4119 160/1K 1.28 10.00 0057 HC 181 62 13.50 74092311 423 78 4147 1000/26 3152405 .66 439665 0153019 24122 32 6.3/10 P8302 # 831 .16 1.20 11.0682 003 14C-18 1.6 16.0 70324111 .68 7409250 8.38 403KM 33 4148 1500/3 74120 22X76 I.3 55227 .23 1.M 24248 .34 12.00 0059 41C-18 . 1.62 740284 8.36 6.3/220 P 6333 P6202 .21 2149 22000/26 1.20 #4121 270/16 1.3 13.50 7410243 88 4510805 80 N5320 2.30 2X3020 1.04 21219 34 15.00 002 12.18 740527M 8.38 6.3/330 7632 42 P6203 .22 P 4150 33000/3 170 74122 330/1K 1.09 1.62 13.0 741324µ 88 45118CN 80 2M0053 1.04 24250 .34 16.02 0077 710.18 32 6.3/470 P6305 46 P6204 .3 74152 1000/0 1.5 P4123 390/IK 1.99 1.82 13.40 745245 .68 a093µ 6.38 451284M .80 293107 1 30 10 18.00 295322 2¿31910 242504 6,3/1,600 P6306 60 76205 33 #4151 1500/50 1.5 #4124 470/1K 1.96 000 60.18 1.60 15.00 742242 124 7409320 123 4516825 1,08 65323 1.84 08 25 .30 18.432 X01 24258 8.3/320 P6307 , .8 12206 .2 74154 220/0 1.2 #412 580/1K 1.99 12-18 1,86 15.00 74152516 .60 750941M 1.96 4515B 1.08 5P.529076 29 70 00 95400 .3I )23 24274 8.3/3,30 7532 ä P6207 .81 #4166 3300/50 1.5 74126 20/16 199 0882 HC -18 1 6 56 W 74152536 60 14094511 11,25 451226 83 X5481 .31 68992924 .36 204275 .29 22.1184 6.3/4,82 Pó/09 1.13 78206 1.01 #4156 470/0 1.20 70127 820/1K 2.3 122 12.16 1.6 16.0 741525155 60 74094711 1125 4518806 63 1,80 66953381 .24 36 N5413 24355 6.3/6,803 P 6310 1.µ P825 22 70157 13800 SO 1.24 74118 100/1K 2.25 48.00 002 114.18 1 6 16.50

lnr. 11,y. key rnl me d.>I'.uum stW senne. hayrrn ee semple tu 000/, Mo4I wets 3,43 by 0,5/ aey n.. be Como, d foe 0 volume discount Itenn Met are ret discounts., are demo ed by IN! ruhr. ND lnl wm91le pm numbs,3. Ahw me. all of the d y the sylxulxsem Mac to On MI Ilx SERVICE CHARGES VOLUME DISCOUNT : m A munrv> 4, vv. nr.nnn,. addresxs,n the U S Lened0 east Mew 04. U.. ck ar :xdr.r ana I7. esta del 111 It y MI, sn 05d4,110 0.76. Pie...e melt ArisLi f 0.88,624.88 Add 63.0 5 0 0.9 99.99. NET News:: Caned. Ind Neer., 63.0 and U7 No Charge 5 13.00.9249 96 WWII ORDERING BT 745888 CALI 1 800 3410539 IAN. sell 218681 66141. BY Mill SEND YOUR ORDER 70 0161885. P.O. M. 877, INN 58., falls. MN 56701. 4 250.0-8099.99. 6 500.0.9999.99 91006 Up CIRCLE 82 ON FREE INFORMATION CARD 102

www.americanradiohistory.com MARK V ELECIRONICS, INC. Since 1985 Gives you more selection in Electronic Kits, Power Amplifiers, Test Instruments and Professional Products.

A indicates the level of difficulty in the assembling of our Products. A Beginner A A Intermediate A A A Advanced * Fully Assembled DYNAMIC NOISE REDUCTION UNIT PROFESSIONAL COLOR LIGHT AMPLIFIERS SM -666 A Complete kit $26.00, Assembled 8 tested $34.00 CONTROLLER SM -328 * KIT Au,mo,.a MODEL DESCRIPTION The SM -666 Dynamic 5.07 Assembled 8 tested TA -001 1W Mini -Amplifier A S - r. Noise Reduction Unit is 6.90 TA -006 6W Mini -Amplifier A ''I to reduce $150.00 TA -007 12W Mini -Amplifier A 11.20 ";designed NÉyr noise during playback TA -10 Stereo Pre-Amp. w/magnetic mic. amp. .. 8.20 from casette tapes, LP The SM -328 profes- TA-28MK2 Digital Voice Recorder A 30.00 S 40.00 .v ,'`_ records and compact sional color light con- TA-50A/B Multi -Purpose Melody Generator A 11.84 16.58 TA -50C Multi -Purpose Melody Generator A 12.65 17.71 discs, as well as FM radio broadcasts. An National Sem- is keyboard troller TA-120MK2 Class "A" Main Power Mono Amp. 31.25 iconductor LM1894 integrated circuit is used to achieve a programmable torease of use, it allows full control of TA -300 30W MuP.HPurpase Single Channel Amp. A .. 20.00 noise reduction of 10dB. The SM -666 has the great ad- intensity and flash rate. It has four separate channels TA -302 60W Stereo Power Booster 50.00 70.00 vantage that it can be used with all musical formats on TA -322I 50W -I- 50W IC Stereo Amp.* wiled level display 35.60 noise reduction systems such as with capacity of 1170 watts per channel. Total wattage playback whereas existing 29.50 C magnetic tapes only. The output capability is 4.68 killowatts. This is equivalent to bulbs TA -323A HO 30W + 30W Stereo Amp. Dolby B and operate with TA -377A FET Stereo Pre -Amp. 59.95 75.00 of the unit is connected directly to the system amplifier input or 9365 -watt colored bulbs and is sufficient for the TA -400 40W Solid State Mono Amp. 28.00 as shown in the schematic. The unit can be switched out or input largest halls and auditoriums. Independent TA -477 120W Mostet Power Mono Amp. A 68.00 bypassed if desired in order to compare the noise reduction Power Amp. 60.92 signal control Professional styled control panel 4 TA -800 80W + 80W DC PreMain 8 advantage when playing a noise signal TA -802 80W + 80W DC Stereo Main Power Amp. .. 45.94 independent outputs independent dimmer controls SPECIFICATIONS : Input signal level: 3.5 V RMS 4 TA -820A 60W + 60W 0CL DC Pre -Main Stereo Amp. AA 48.00 Chaser speed controls Automatic chaser operation MAX 20 Kohm Noise reduction: 10dB Power TA -1000A 100W Class "K Main Power Mono Amp. AA 59.69 80.58 supply: 9 to 12V recommended Operating cur- 4 preset chaser programs Clockwise chaser control TA -1500 100W x 2 Class"A- DC Stereo Pre -Main Amp.A 73.70 95.81 rent: 27mA MAX Anti -clockwise chaser control. TA -2400A Electronic Echo8 Revelation Amp. 93.30 116.80 90.00 Input sensitivity(music model): TA -2500 HO Pre-Amp. w/10 band graphic equalizer* * SPECIFICATIONS: TA -2800 Hi-Fi Bi-Fet Pre -Amp. w/3 way time control AA 48.90 TALKING CLOCK 100mV, (music 8 program): 2V Output power: TA -3000 Stereo Simulator 33.20 43.38 MYNAH 8504 1170W per channel 4680W total Power require- TA -3600 300W HO Hi-Fi Power Mono Amp. .. 86.00 110.00 ment: 105-120V, 60hz Dimensions: 14.32" wide, 9" high, 3.19" deep. MISCELLANEOUS MULTIPURPOSE MELODY GENERATOR MODEL DESCRIPTION KIT TY-IA Battery Flourescent Light Driver S 5.19 TA-50A C TMSO"+ c.... w n' w PARROT 8501 / B / /.nOY054.MISI TY-7 Electronic Touch Switch 7.15 TeSOC 1. Talk r..F USI] TV -8 ELectronic Lotto 15.00 Push button for voice announcement of time. 2. Read Mantled Mod II Control Switch 5.19 out. Twelve hours system display for hour, minute, second (by S i11 The TA -50 melody generator uses 1Y -11A Multi-Functional w/timer 16.63 y the latest CMOS ROM techno- TY-12A Digital Clock A color flash), AMA PM. 3. Display: Three display modes of TY-13 Color Led Audio Level Meter 20.15 time, alarm time 8 data 4. Alamo On / off switch with thirty logy. It plays 8 to 10 different 625 TY-14 Electronic Shock A seconds voice alarm. 5. Snooze: Reminder voice alarm of tunes depending on the model It TY-18 High Precision Sound Control Switch 922 thirty seconds after 4 minutes of first voical alarm. 6. Volume: operates on two M size batteries TY-20 V Shape Color Led Level Meter 21.45 due to its small current demand. 7Y-238 3 Channel Color Light Controler A* .. 71.50 38250 Two level of voice output 7. Language available: English You can adapt the generators to TY-25 Stereo Loudspeaker Protector 12.65 PARROT 8501 . __....__...._. $12.00 1V-35 FM Wireless Microphone 9.22 MYNAH ..... door bells, musical boxes, electronic clock alarms and many 8504 $12.00 (NOT A KIT) TY-36 AC/DC Quartz Digital Clock A 18.00 none. There we three models to choose from as listed below. TY-38 Sound/Touch Control Switch 12.00 STEREO PRE-MAIN AMPLIFIER Output power. 500mW Out- SPECIFICATIONS: TY-41MK111 Infrared Remote Control Unit A 15.00 25.00 100W x 2 CLASS "A" DC put impedance: 4 to 8ohms Power requirements: TV -41 MKV Infrared Remote Control Unit A A 20.00 35.00 1.5 to 5 volts DC @ 100ma Dimensions: 2.8" x 1Y-42 Bar/Dot Level Meter A 24.15 TA -I500 AAA 2.4"x0.8" TY-43 31/2 Digital Panel Meter 33.00 4620 Complete kit $73.70 TA-50A - Jingle Bell, Silent Night, Rudolph The Rednosed 7Y-4$ 20 Steps Bar/Dot Audio Level Display A 38.45 Assembled 8 tested $95.81 TY-47 Superior Electronic Roulette A 19.46 Reindeer, 0 Come, All Ye Faithful, Santa Claus Is Coming To The TA is a SM -222 7 Bands Graphic Equalizer 26.80 38.80 -1500 amplifier Town, Joy To The World, I Wish You A Merry Christmas, Hark, stereo preamplifier and SM-328 4 Channel Professional Color* Light Controller * . 150.00 The Herald Angels Sing. SM-333 Audio/Video Surround Sound Processor 62.00 83.00 power amplifier featuring TA -50B - London Bridge Is Falling Down, Are You Sleep- 5M-666 Dynamic Noise Reduction * 26.00 34.00 + e low noise integrated circuits ing, Joy Symphony, Wiegenlied, Row Your Boat, Happy T-1 LCD Thermometer Clock w/irrcutdcor sensor * 22.00 in the preamplifier section A fully regulated power supply Birthday, Home Sweet Home, Melody on Purple, Bamboo. T-2 LCD Thermometer Clock w/ F 8 C measurement * 19.80 insures stable, low distortion operation of this section. The TA -50C- L'eau Vive (Living Water), Home on the Range, 8501 Parrot Talking Clock * ..... 12.00 power amplifier section features fully complementary power 8504 Mynah Talking Clock 12.00 Romance De Amor, Comic' Thro' The Rye, Wedding March, * output transistors and direct coupled circuit configuration. The are fully protected by an automatic Happy Birthday, Humoresque, Lorelei, The Last Rose of output transistors POWER SUPPLIES bias circuit and the loudspeakers are fully protected against Summer, Love Song From Sikang disconnect relay circuit An MODEL DESCRIPTION KIT "w..ml.a damage by a fast acting speaker 300W HI-FI POWER AMPLIFIER (MONO) additional feature, not found on many similar amplifiers, is TR -100A 0-15V 2A Regulated DC Power Supply 59.50 69.50 provision to use a microphone with the amplifier. TA-3600 AA A TR-355A 0-15V 5A Regulated DC Power Supply 12.92 This amplifier requires only the addition of an external power Assembled & tested S I 10.00 TR-355B 0.30V 3A Regulated DC Power Supply 12.92 transformer tor a fully operational unit. Power Completed Kit $86.00 Transformer $38.00 TR-503 0-50v 3A Regulated DC Supply 14.76 SPECIFICATIONS : Power output: 80 watts per channel into 8ohms, 100 watts per channel into 10,000 OF 80V E. Cap $20.00 INSTRUMENTS 4ohms Total harmonic distortion: Less than The TA-3600 is an extremely 0.03% Frequency response: Aux input. 5 to KIT "...mown high power amplifier specifi- MODEL DESCRIPTION 50,000hz 49.2dB,1-2dB Frequency response: Power amplifier section, DC to 200khz Sensiti- reproduce SM -43 31/2 Multi -Functional Led D.P.M 34.50 43.00 cally designed to vity: Phono: 2.5mV @ 47K Aux: 150mV @ 47K Mir: SM -48 41/2 Hi-Precision D.P.M. 38.00 48.00 the high dynamic range 6mV @ 10K Output: Tape: 150mV @ 471( Pre - SM -48A 41h Hi -Precision D.P.M. w/ stndrd case 41.20 52.00 amp: 1V @ 600ohms Power transformer. 26 V to available on compact discs. It 150MC Digital Frequency Counter 79.00 90.00 5M-100 32VACx2 @ 6A has low noise, high stability, FC1000A 1 GHz Frequency Counter .. 192 00 low distortion, extended fre- COLOR LIGHT CONTROLLER quency range and high efficiency in a compact package. METAL CABINETS Two of these units with appropriate power supply and TY-23B AAA* Complete kit $71.50 MODEL DESCRIPTION MATCHING EA SET pre-amplifier are required for stereo reproduction. . LG -1273 3"x12"x7" TA -2800, TA -377A $20.16 SPECIFICATION: Power output: 300 watts sine Assembled 8 wave 540 watts music power Frequency response: ' LO -1684 4"x16"x8" TA -3221 TA-323A TA -377A 24.64 tested $82.50 Total harmonic distortion: Less than 0.05% Sensitivity IVms at 47K Power requirements: LG -1924 4"x19"x11.5" TA-802, TA-820A, TA-1500, TA -120, TA-800, TA -1000A 30.00 Asa result of the advanced technology, tnis unit can control 60 to 75VDC at 8amp. various colorful spot lights or bulbs. The visual effect of which TAd77, TA-800, TA-1500, TA -1000A LG -1925 5"x19"x11.5" 33.00 is most suitable in places like party, disco, electronic game TRANSFORMERS centre and also in lightings for advertisements. Total output power is 3000W (1000W/Ch) whichcan control 30 pieces of MODEL DESCRIPTION MATCHING PIECE 100W or 600 pieces of 5W color light bulbs. a 001 56V CT to 60V CT 6A TA -800, TA -802, TA -820A TA -10000. FEATURES: 1."Music" mode, Audio signal is divided TA-1500 $25.00 into high, middle and low frequency to drive 3 * 002 72V CT 3A TR -503, TA -3221. TA -3230. TA-400 19.00 groups of lights, It has Independent controller for u 003 80V CT 6A TA -477 24.00 sensitivity. 2. "Chasing" mode, Electronic circuit n 004 48V CT 6A TA -120 19.00 automatically controls 3 groups of color lights in n 005 52V CT 3A TR -355B 12.00 sequential ON and OFF, also it has a speed con- 006 36V CT 5A TR -355A 13.60 troller and shelf -program "Chasing Mode" on the 007 112V CT 8A TA -3600 38.00 P.0 Board.

- WE ACCEPT MAJOR CREDIT CARDS, MONEY ORDERS AND CHECKS - BUSINESS & SHOWROOM HOURS : (PACIFIC TIME) MON. - FRI.: 9:30 AM. - 5:00 P.M., SAT.: 10:00 AM.- 5:00 P.M. TERMS: $10.00 MIN. ORDER $20 MIN. CHARGE CARD ORDER WE SHIP UPSGROUND ADD 1096OF TOTAL ORDER (M I N.$3.00) FOR SHIPPING OUTSIDE USA, ADD 20% (MIN. $5.00) TRANSIT INSURANCE: ADD 5% OF TOTAL (OUTSIDE USA ONLY). CA RESIDENTS ADD SALES TAX ALL MERCHANDISE SUBJECT TO PRIOR SALE PRICES ARE SUBJECT TO CHANGE WITHOUT NOTICE WE ARE NOT RESPONSIBLE FOR TYPOGRAPHICAL ERRORS.

CATALOG OR INFORMATION : 213-888-8988 PHONE ORDER : 1.800-423.3483,(IN CALIF.) 1 -800 -521 -MARK FAX : 213-888-6868 MARK V ELECTRONIC , INC. - 8019 E. Slauson Ave., Montebello, CA 90640 C® CIRCLE 93 ON FREE INFORMATION CARD 103

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MEMORY 101.111, PROTOTYPE CARDS FR-4 EPDXY GLASS LAMINATE WITH GOLD PLATED DYNAMIC RAMS EDGECARD FINGERS AND SILK SCREENED LEGENDS PARTY SIZE SPEED PINS PRICE 4116-150 16384x1 150ns 16 .99 4164-150 65536x1 150ns 16 2.49 4164-120 65536x1 120ns 16 2.89 4164-100 65536x1 100ns 16 3.39 TMS4464-12 65536x4 12Ons 16 9.95 Call our BBS. (408) 559-0253 for more info in SIG file Hitech" 41256-150 262144x1 150ns 16 4.49 TMs month's topic is floppy drive compatibility. There are 41256-120 262144x1 120ns 16 4.99 360K 5-1/4', 720K 41256-100 262144x1 100ns 16 5.49 3-1/7, 1.2Meg 5-1/4' and 1.44Meg 3-1/2' 41256-80 262144x1 8Ons 16 5.99 drives, any of which can be used on most PC's and PC clones. 41256-60 262144x1 6Ons 16 7.99 Recent Improvements in floppy Controllers make using high 414256-100 262144x4 100ns 20 14.95 density drives on 8088 -based machines o viable option. FOR XT 414256-80 262144x4 8Ons 20 16.95 To simplify, well eliminate Me redundant choices. A JDR-PR1 WITH +5V AND GROUND PLANE 27.95 1 MB -120 1048576x1 12055 18 13.95 1.2Meg drive can work with both high density 1.2Meg Bopples JDR-PR2 ABOVE WITH I/O DECODING LAYOUT 29.95 1 MB -100 1048576x1 100ns 18 14.95 and low density 360K floppies.' A high density 3-1/7 1.44Meg JDR-PR2-PK PARTS KIT FOR JDR-PR2 ABOVE 8.95 1 MB -80 1048576x1 8Ons 18 15.95 drive can use both the high densify1.44Meg and the low FOR AT density 720K disks. Unless you know that you will never need JDR-PRIG BIT WITH I/O DECODING LAYOUT 34.95 SIMM MODULES high density capability, is a good universal standard one JDR-PRIO-PK PARTS KIT FOR JDR-PR10 ABOVE 12.95 PARTY SIZE SPEED FOR PRICE 3-1/2' and one 5-1/4" high density drive. 41256Á9B-12 256K x 9 12055 PC 59.95 Now for the bombl Big Blue uses a different method to FOR PS/2 JDR-Pß32 41256Á9B-80 256K x 9 8Ons PC 69.95 distinguish between 720K and 1.44Meg drIves. While most of 32 BIT PROTOTYPE CARD 69.95 421000A8B-10 1MB x8 100ns MAC 169.95 JDR-PR/6 16 BIT WITH I/O DECODING LAYOUT 49.95 the manufacturers look for and detect the High Density hole in 421000A9B-10 1MB x9 100ns PC JDR-PR16-PK PARTS KIT FOR JDR-PR16 ABOVE 15.95 169.95 a high density diskette, they read the data to make that 421000Á9B-80 1MB x9 8Ons PC 179.95 JDR-PR16V 16 BIT FOR VIDEO APPLICATIONS 39.95 determination. This causes a problem when a Low Density disk without the hole is written In the high density mode. So it you EXTENDER CARDS STATIC RAMS get o 3-1/7 disk that a friend says is formatted at 1.44Meg, SIMPLIFY FROTOTYPING AND TESTING PARTY SIZE SPEED PINS PRICE make sure 4 has a High Density hole or it probably won't recd EXT-8088 8 -BIT FOR 8088 MOTHERBOARDS 29.95 TMM2016-150 2048x8 150ns 24 3.25 in your clone. EXT-80286 16 -BIT FOR 286/386 MOTHERBOARDS 39.95 HM6116LP-2 2048x8 120ns 24 5.49 Derick Moore, Director of Engineering EXT-16 MICROCHANNEL 16 -BIT 69.95 HM6264LP-15 8192x8 150ns 28 8.95 'An infrequent problem can occur when a 360K drive ú LEXT-32 MICROCHANNEL 32 BIT 999J HM6264LP-12 8192x8 12Ons 28 9.95 `written in o 1.2Meg drive and h then read in a 3601( drive. HM43256LP-15 32768x8 150ns 28 19.95 A HM43256LP-12 32768x8 120ns 28 21.95 HM43256LP-10 32768x8 100ns 28 24.95 EPROMS PC BREADBOARD -ON-A -CARD PARTY SIZE SPEED Vpp PINS PRICE 62 BUS LINES 2708 1024x8 450ns 25V 24 4.95 USE UP TO 24 14-PIN ICS r MATH COPROCESSORS 2716 2048x8 450ns 25V 24 3.49 1940 TIE POINTS 2716.1 2048x8 350ns 25V 8-BIT COPROCESSORS 24 3.95 DB25 D -SUB CONNECT. 5 YEAR 2732A 4096x8 25Ons 21V 24 3.95 PDS -604 $49.95, 8087 5 MHz 89.95 2764 819208 450ns 12.5V 28 3.49 8087-2 8 MHz 129.95 WARRANTY 2764-250 8192x8 250ns 12.5V 28 3.69 8087-1 10 MHz 169.95 2764-200 819208 200ns 12.5V 28 4.25 18 -BIT COPROCESSORS 27C64 8192x8 250ns 12.5V 28 4.95 SOLDER STATION 80287 6 MHz 139.95 27128 1638408 25Ons 12.5V 28 4.25 80287-8 8 MHz 209.95 271288-200 16384x8 200ns 12.5V 28 5.95 UL APPROVED 80287-10 10 MHz 239.95 27256 32768s8 250ns 12.5V 28 4.95 ADJUSTABLE HEAT SETTING 27256-200 32768x8 32-BIT COPROCESSORS 200ns 12.5V 28 5.95 TIP TEMPERATURE READOUT 27C256 32768x8 25Ons 12.5V 28 5.95 REPLACEMENT TIPS @ 80387-16 16 MHz 359.95 27512 65536x8 25Ons 12.5V 28 8.95 62.95 80387-SX 16 MHz 319.95 27C512 65536x8 25055 12.5V 28 9.95 168-30 $59.95, 80387-20 20 MHz :99.95 L27C101-20 131072x8 200ns 125V 32 29.95_4 80387-25 25 MHz 499.95 INCLUDES MANUAL 80387-33 33MHz 649.95 & SOFTWARE GUIDE A IC SOCKETS/DIP CONNECTORS EPROM ERASERS SOLDERTAIL WIREWRAP ZIF SOCKETS r 8 PIN ST .11 8 PIN WW .59 ZIF -14 5.95 74 SERIES LOGIC DATARASE ll '39.95 14 PIN ST .11 14 PIN WW .69 ZIF -16 5.95 SHIRT POCKET SIZE, 16 PIN ST .12 16 PIN WW .69 ZIF -20 6.95 7400 .19 74LS32 .18 74LS245 .79 ALL SIZES UP TO 4 AT A TIME 18 PIN ST .15 18 PIN WW .99 ZIF -24 7.95 741.573 .29 74L500 .16 7415273 .79 ERASES MOST 20 PIN ST .18 20 PIN WW 1.09 ZIF -28 7.95 7474 EPROMS IN 3 MINUTES 74LS02 .17 .33 745288 1.69 24 PIN ST 20 24 PIN WW 1.49 ZIF -40 10.95 74LS74 DATARASE II 7404 .19 .24 74LS322 3.95 28 PIN ST .22 28 PIN WW 1.69 74574 .49 74LSO4 .16 74LS367 .39 40 PIN ST .30 40 PIN WW 1.99 VOLUME 74SO4 .29 74LS138 .39 DISCOUNTS 74LS373 .79 SPECTRONICS Y of Intensity Unit 7406 74LS155 .59 Model Timer .29 74LS374 .79 CORPORATION Chips (uW/Cm2) Cost CAWI 7408 .24 74LS163 .39 74LS393 .79 74LS08 .18 74LS240 .69 7415682 3.20 PE-140 NO 9 8,000 $89 SOLDER-CUP DSUBS, IDC'S 7432 .29 74LS244 .69 741_S688 2.40 PE-140T YES 9 8,000 $139 -_ PE-240T YES 12 9,600 $189 MALE FEMALE DE20 .55 DE34 .89 PL -265T YES 30 9,600 $255 D809P .45 DBO9S .49 DS20 .65 DB15P .59 DB15S .69 DS34 75 C.P.U.'s r MISC PALS HDB15P 1.49 HDB15S 1.59 DB09P 1.39 DB19P .69 8000 DAC0800 3.29 16L8 2.95 DB19S .75 DB09S 1.45 DB25P .69 8052AH 1793 9.95 1684 2.95 D825S .75 DB25P 2.25 DB37P 1.35 BASIC 34.95 COM8116 8.95 1686 2.95 DB37S 1.39 IDB25S 2.35 8088 5.99 MC146818 5.95 16R8 2.95 POWER SUPPLIES LDB50P 1.85 DB50S 2.29, MM58167 9.95 20L8 8250 6.95 4.95 135 WATT POWER SUPPLY 8251A 1.69 INS8250 6.95 2084 4.95 APPROVED 8253-5 1.95 NS16450 10.95 2086 4.95 UL CABLES AND GENDER CHANGERS 8254 9.95 LM317T .69 2088 4.95 +5V @15A, +12V @ 4.28, 8255-5 2.49 NE555 .29 20%8 4.95 -5V @ .5A, -12V @ SA MOLDED; GOLD-PLATED CONTACTS; 100% SHIELDED LM741 .29 8741 9.95 PS-135 $59.95 CBL-PRINTER 6 FT. PC PRINTER CABLE 9.95 7805T .49 8748 7.95 PAL KIT iiPS -150 150W SUPPLY $69.95 CBL-PRNTR-25 25 FT. PC PRINTER CABLE 15.95 78127 .49 8749 9.95 AN ENTRY-LEVEL CBL-PRINTR-RA RIGHT ANGLE PRINTER CABLE 15.95 75150 1.95 100 WATT POWER SUPPLY 8755 14.95 COMPLETE PAL CBL-D025-MM DB25 MALE -0825 MALE 6 FT. 9.95 75154 1.95 UL APPROVED DEVELOPMENT CBL-DB25-MF DB25 MALE-DB25 FEMALE 6 FT. 9.95 14411 9.95 8500 KIT FROM CUPL. +5V @ 20A, +12V @ 7A, CBL-9-SERIAL DB9 FEMALE-DB25 MALE 6 FT. 6.95 -5V @ .SA, -12V @ .5A 65CO2 7.95 FULL SUPPORT CBL-KBD-EXT 5 FT. KEYBOARD EXTENSION 7.95 6522 2.95 CRYSTAL FOR 1618, 16R4, PS-200 $89.95 CBL-CNT-MM 36 -PIN CENTRONICS -M/M 14.95 Y-20 OSCILLATORS 16R6, 16R8, 20L8. APPLE TYPE SUPPLY CBL-FDC-EXT 37 -PIN EXT. FLOPPY CABLE 9.95 20R4, 20R6, 20R8. CBL-MNT-9 9 -PIN MONITOR EXTENSION 6.95 V20 6.95 1.0MHz 5.95 WITH AND 20X8. APPLE CONNECTOR 15 V20-8 8.95 1.8432 5.95 CBL-MNT-15 -PIN MONITOR EXTENSION CABLE 9.95 MOD -MPL +5V @ 6A,+12V @ 3A, CBL-MODEM MODEM V20-10 11.95 20.0 4.95 -SOFT -DB25-DB25 FEMALE 6.95 -5V@ IA. -12V@1A GENDER-VGA DB9-0815 ADAPTOR 4.95 V30 13.9_54 24.0 4.95 $99.95 J PS-A $59.95-4 'GENDER -9-25 DB9-DB25 SERIAL ADAPTOR 4.95 PARTIAL LISTINGS ONLY -CALL FOR FREE 84 -PG CATALOG!

JDR MICRODEVICES AND THE JDR MICRODEVICES LOGO ARE REGISTERED TRADEMARKS OF JDR MICRODEVICES. IBM. AT. PS.2 ARE TRADEMARKS OF INTERNATIONAL BUSINESS MACHINES. CIRCLE 113 ON FREE INFORMATION CARD 104 DEALERS CIRCLE 170 ON FREE INFORMATION CARD

www.americanradiohistory.com HARD DISKS KITS te4.211L1141n 14- VGA 2400 BAUD COMPATIBLE 20 MB $199 20 MB $249 MODEM PACKAGE $499 30 MB $219 30 MB $279 $9995 Seagate 720 X 540 MAX RESOLUTION, 640 X 480 IN 16 COLORS, 40 MB $319 528 X 480 RESOLUTION IN 256 COLORS IBM STYLE MONITOR HAYES COMPATIBILITY VGA, EGA, CGA, AND MGA COMPATIBLE 28 MS $389,1111 AUTO DIAUANSWER VGA-PKG (INCLUDES VGA CARD AND MONITOR) SELF -TEST ON POWER UP Q FULL AND HALF DUPLEX VGA MONITOR $359 60 MB $38 TOUCHTONE OR PULSE DIALING 2ND PHONE JACK 14" ANALOG VGA GLARE RESISTANT SCREEN 720 X 480 PRO -241 TILT/SWIVEL BASE FRONT MOUNTED POWER SWITCH 80 MB $569 VGA -MONITOR AVG. FORM DRIVE AT F/H RELISVS MULTISYNCH $429 SIZE MODEL SPEED FACTO ONLY KIT DFI HANDY SCANNER 3000 PLUS FULL FEATURED MULTISCAN MONITOR WITH UNLIMITED COLORS 1024 X 768 RESOLUTION, 14" NON -GLARE DISPLAY 20MB ST -225 85 MS 5-1/4- $199 $249 $309 AUTO SWITCHING TTUANALOG VIDEO INPUT 20MB ST -125 40 MS 3-1/2" $259 $299 $373 $2199Ì NEW IMPROVED! JDR-MULTI 30MB RLL ST -238 65 MS 5.1/4" $219 $279 $379 NOW WITH PAINT- 30MB RLL ST -138 40 MS 3.1/2' $289 $339 $429 IMPROVED CLARITY, BRUSH PLUS AND EGA SPECIAL! CARD & MONITOR --JUST $479 40MB ST -251 40 MS 5.1/4" $319 $369 $429 HIGHER SCANS UP SPEED! IMAGE TOOLS 40MB ST -251-1 28 MS 5-1/4" $389 $439 $499 TO 4.1" WIDE IMAGES 100, 200, 300, 60MB RLL ST -277 40 MS 5-1/4" $389 $449 $549 400 DPI BOTH DIRECTIONS B&W & EGA -MONITOR 14" ROB MONITOR $339.00 80MB -4098 28 MS 5.1/4" $679 3 HALF -TONE MODES 32 LEVELS OF JDR-RGB 14" RGB MONITOR TILT/SWIVEL BASE $239.95 ST $589 GRAY SCALE HERCULES, CGA, EGA AND VGA COMPATIBLE JDR-MONO 12" TTL MONOCHROME- GREEN $69.95 JDR-AMBER 12" TTL MONOCHROME AMBER $69.95 HS -3000 WITH HALO DPE & IMAGE EDITOR SOFTWARE OCR -SOFT CHARACTER RECOGNITION SOFTWARE $99.95 YJit^1' 150MB DI$ UPRIGHT ken QUALITY DRIVE KIT 5-1,4" HARD DISK, FLOPPY/HARD CASE $29995 KEYBOARDS CONTROLLER, CABLES, MOUNTING STANDARD KEYBOARDS: HOLDS ALL HARDWARE & SOFTWARE. 1355-PKG SPACE SAVING DESIGN SIZES BTC-5060 AUTOSENSE FOR XT/AT $59.95 OF MOTHERBOARDS AND INCLUDES: MAX -5060 WITH TACTILE FEEDBACK $64.95 250W POWER SUPPLY MOUNTS FOR 3 FLOPPY & 4 HARD DRIVES ENHANCED KEYBOARDS: TURBO & RESET SWITCH LED SPEED BTC-5339 AUTOSENSE FOR XT/ AT, AUTOREPEAT $69.95 DRIVE DISPLAY POWER & DISK LED'S 1.44MB 3-1/2" 'CLICK" STYLE ALL HARDWARE, FACEPLATES & SPEAKER K103 -A AUDIBLE $84.95 $84.95 . CASE-100 MAX -5339 MAXI SWITCHW/TACTILE FEEDBACK $9995 CASE-FLIP FOR 8088 MB'S $39.95 CASE -SLIDE FOR 8088 MB'S $39.95 ULTRA HIGH DENSITY TOO CASE -70 FOR 286 MB'S $89.95 READ/WRITE 720K DISKS, MODULAR CIRCUIT TECHNOLOGY FACEPLATE CASE -50 FOR MINI 286 MB'S $59.95 FDD-1.44X BLACK FDD-1 .44A BEIGE FACEPLATE CASE -JR MINI -286 W/150W PS $149.95 DRIVE CONTROLLERS: DRIVER MCT-FDC FLOPPY DISK CONTROLLER $29.95 FDD-1.44 SOFT SOFTWARE $19.95 MCT-FDC-HD 1.44MB FLOPPY CONTROLLER $49.95 1/2 HEIGHT FLOPPY DISK DRIVES: MCT-HIDC HARD DISK CONTROLLER $79.95 FD -55B 5-1/4' TEAC DS/DD 360K $99.95 DFI SERIAL MOUSE $3995 MCT-RILL RLL CONTROLLER $89.95 FD -55G 5-1/4" TEAC DS/HD 1.2M $129"95 3 -BUTTON OPTO -MECHANICAL MCT-FH FLOPPY/HARD CONTROLLER $139.95 FDD-360 5-1/4" DS/DD 360K $69.95 200 D.P.I. 5-1/2' CABLE MCT-AFH 286/386 FLOPPY/HARD $149.95 FDD-1.2 5-1/4" DS/HD 1 2M $95.95 USES SERIAL PORT COM 1/2 MCT-AFH-RLL 286/386 RLL CONTROLLER $199.95 INCL. SOFTWARE DRIVERS DISPLAY ADAPTOR CARDS: DMS -200E MCT-MGP MONOCHROME GRAPHICS $59.95 MOUSE & HALO-DPE SOFTWARE MCT-CG COLOR GRAPHICS ADAPTOR $49.95 MOTHERBOARDS DMS -200 $59.95 MCT-EGA ENHANCED GRAPHICS ADAPTOR $149.95 MCT-VGA-8 8 -BIT VGA, ANALOG ONLY $199.95 25MHZ 386 $1049 MCT-VGA-16 16 -BIT VGA, 1024X768 RES. $329.95 10/25 MHZ C®: LOGITECH MICE,, MONOGRAPHICS MULTI I/O $119.75 MCT-MGMIO 16 MB RAM CAPACITY - 8MB r s THREE -BUTTON SERIES 9 MCT-MGAIO 286/386 MONOGRAPHICS I/O $99.95 ON-BOARD(0K), 8 MB RAM CAR

USES 256K OR 1 MB DRAMS LODIILbn SERIAL PS/2 COMPATIBLE. MULTIFUNCTION CARDS: MCT-MIO MULTI I/O FLOPPY CONTROLLER 8 SLOTS: 1X32-BIT RAM LOGC9 SERIAL MOUSE $98.95 $79.95 MCT-IO MULTI I/O CARD 2X 8 -BIT & 5X 16 -BIT LOGC9-C SERIAL MOUSE' $79.95 $59.95 MCT-AMF 286/386 MULTIFUNCTION $139.95 SHADOW RAM FOR BIOS LOGC9-P SERIAL MOUSE WITH PAINTSHOW $109.95 MCT-AIO 286/386 MULTI I/O CARD $59.95 VIDEO AMI BIOS LOGC9-PC SERIAL MOUSE WITH PAINT/CAD $154.95 INTERLEAVED MEMORY BUS MOUSE $89.95 LOGB9 MEMORY CARDS: ADJUSTABLE BUS SPEEDS LOGB9-P BUS MOUSE WITH PAINTSHOW $104.95 MCT-RAM 576K RAM CARD $59.95 MCT-386MB25 LOGB9-PC BUS MOUSE WITH PAINT/CAD $149.95 MCT-EMS EXPANDED MEMORY CARD $129.95 MCT-386MB20 10/20MHZ 386 $849.00 NOT PS/2 COMPATIBLE MCT-AEMS 286/386 EMS CARD $139.95 MCT-386-M 8MB RAM CARD (0K) $149.95 12MHZ MINI -286 $299 MODULAR PROGRAMMING SYSTEM EPROM MODULE $119.95 AT COMPATIBLE - KEYBOARD SELECTABLE 8/12MHZ PROGRAMS 2432 PIN EPROMS, CMOS EPROMS INTEGRATED MODULAR SYSTEM EASILY EXPANDS! ALL EXPANDABLE TO 4MB ON -BOARD WITH 1MB DRAMS (0K) & EEPROMS FROM 16K TO 1024K HEX TO OBJ SIX 16-BIT & TWO 8 -BIT SLOTS AMI BIOS LED SUPPORT MODULES USE A COMMON HOST ADAPTOR CARD --USE JUST CONVERTER AUTO, BLANK CHECK/PROGRAM/ ONE SLOT TO PROGRAM EPROMS, PROMS, PALS & MORE VERIFY VPP 5, 12.5, 12.75, 13, 21 8 25 VOLTS MCT-M286-12 NORMAL, INTELLIGENT, INTERACTIVE & QUICK MCT-M286 6/10MHZ MINI-286 $269.95 r PULSE PROGRAMMING ALGORITHMS MCT-M286-16 8/16MHZ 286 $489.95 HOST ADAPTOR CARD $29.95 MOD -MEP MCT-M286-20 10/20MHZ 286 $589.00 INTERFACE FOR UNIVERSAL ALL MOD -MEP -4 4 -EPROM PROGRAMMER $169.95 MCT-XMB STANDARD 4.77MHZ 8088 $87.95 THE PROGRAMMING MODULES! MOD -MEP -8 8 -EPROM PROGRAMMER $$2259.95 MCT-TURBO 4.77/8MHZ 8088 $95.95 ADDRESSES SELECTABLE MOD -MEP -1616 -EPROM PROGRAMMER 99.95 MCT-TURBO-10 4.77/10MHZ SINGLE CHIP 8088 $99.00 PREVENTS CONFLICTS MOLDED CABLE DIGITAL IC MODULE $129.95 MOD -MAC TESTS TTL, CMOS, DYNAMIC & STATIC RAM AUTO SEARCH FOR UNKNOWN PART NUMBERS EPROM PROGRAMMER $12995 UNIVERSAL MODULE $499.95 USER -PROGRAMMABLE TEST PROCEDURES PROGRAMS 27XX AND 27XXX EPROMS UP TO 27512 PROGRAMS EPROMS. EEPROMS, MOD-MIC SUPPORTS VARIOUS PROGRAMMING FORMATS 8 PALS. BI -POLAR PROMS, 8748 & 8751 VOLTAGES SPLIT OR SERIES DEVICES; 16V8 AND 20V8 GALS PAL MODULE $249.95 COMBINE CONTENTS 0 SEVERAL EPROMS OF (GENERIC ARRAY LOGIC) FROM LATTICE." PROGRAMS MMI, NS, TI 20 & TI 24 PIN DEVICES DIFFERENT SIZES NS, SGS TESTS TTL, CMOS, DYNAMIC BLANK CHECK, PROGRAM, AUTO, READMASTER. READ, WRITE, COPY, & STATIC RAMS LOAD DISK, SAVE DISK, VERIFY & SECURITY FUSE BLOW BLANK CHECK & VERIFY EDIT, BLANK CHECK, PROGRAM, AUTO, MOD -MPL READ MASTER, VERIFY AND COMPARE SOFTWARE FOR HEX TEXTOOL SOCKET FOR .3" TO .6"W. IC'S (8-40 PINS) CUPL SOFTWARE -ENTRY-LEVEL PAL DEV. KIT. AND INTEL HEX FORMATS MOD-MUP MOD -MPL -SOFT $99.95 MOD -EPROM 11 1mMIII.

Terms: Minimum order $10.00. For shipping & handling include $3.50 for ground and JDR MICRODEVICES, 2233 BRANHAM LANE, SAN JOSE 95124 $4.50 for air. Orders over 1 lb and foreign orders may require additional shipping LOCAL (408) 559-1200 FAX (408) 559-0250 TELEX 171-110 charges -please contact the sales department for the amount. CA residents must include applicable sales tax. Prices subject to change without notice. We are not RETAIL STORE: 1256 S. BASCOM AVE.. SAN JOSE, CA responsible for typographical errors. We reserve the right to limit quantities and to substitute manufacturer. All merchandise subject to prior sales. A full copy of our +z+ (408) 947-8881 HOURS: M -F 9-7 SAT. 9-5 SUN. 12-4 terms is available upon request. Items pictured may only be representative. Mostete-Cord ORDER TOLL FREE 800-538-5000 COPYRIGHT 1989 JDR MICRODEVICES CIRCLE 113 ON FREE INFORMATION CARD DEALERS CIRCLE 170 ON FREE INFORMATION CARD

www.americanradiohistory.com ADVERTISING INDEX VALUE -PRICED TEST EQUIPMENT RADIO -ELECTRONICS does not assume any responsibility for errors that may appear ALL WITH A 2 YEAR WARRANTY! in the index below.

Free Information Number Page NRI Schools 8, 11

108 AMC Sales 82 185,186 Optoelectronics 14, 93

182 Ace Communications 79 Pacific Cable 91

75 Ace Products 75 56 Parts Express 97

81 AIS Satellite 75 78 Radio Shack 77 35 MHZ DUAL TRACE OSCILLOSCOPE $49995 WIDE BAND WIDTH VARIABLE HOLDOFF 107 AU Electronics 100 191 SCO Electronics 79 MODEL -3500 (SHOWN) Amazing Concepts 96 178,179 Sencore 27, 20 MHZ DUAL TRACE OSCILLOSCOPE 8$59.95 CV3 TV SYNC FILTER COMPONENTS TESTER MODEL 2000 106 American Design Components .. 101 Star Circuits 81

THE ULTIMATE $ 95 84 Appliance Service 75 83 Synergetics 68 3.5 DIGIT DMM BASIC DC ACCURACY ±0.25% 34 RANGES 67 Banner Technical Books 72 188 Tab 15 TEMP, TRANSISTOR & RESISTANCE FEATURES 98 Beckman Industrial 17 Tektronix 7, 18 DMM-300 (SHOWN) 3.5 DIGIT 109 C & S Sales 71 189 Tentel 22 FULL FUNCTION DMM 949.95 BASIC DC ACCURACY x0.2525% 50 Caig 81 123 Test Probes 13 22 RANGES DMM-200 $49.95 70 CEI 90 250-254 Test Probes 13 3.5 DIGIT POCKET SIZE DMM $29.95 BASIC DC ACCURACY ±0.5ó 14 RANGES 60 CIE 5, 31 64 Video -Link 92 DMM-100 95 3.5 DIGIT PROBE TYPE OMM $54 Command Productions 22 176 Viejo Publications 72 AUTORANGING AC/DC 2V - 500V, 58 Cook's Institute 32 177 WPT Publications 73 RESISTANCE 2K 2M DPM-1000 (SHOWN) 69 Crystek 23 Gernsback Publications, Inc. HIGH/LOW LOGIC PROBE 817.95 500-B Bi -County Blvd. 127 Deco Industries DETECTS TTL/CMOS LOGIC STATES 75 Farmingdale, NY 11735 MEMORY FUNCTION FREEZES DATA FOR LATER USE 1-516-293-3000 LP -2800 82 Digi-Key 102 Fax 1-516-293-3115 PULSER PROBE FOR QUICK DEBUGGING 819.95 President: Larry Steckler Electronics Book Club 46 INJECTS PULSE INTO TEST CIRCUIT -VARIABLE WIDTH Vice President: Cathy Steckler TTL, DTL. TRL, HTL, HINIL, MOS, 8 CMOS COMPATIBLE `P-540 J 187 Electronic Goldmine 97 For Advertising ONLY 1-516-293-3000 121 Fluke Manufacturing CV2 Fax 1-516-293-3115 JIM'S BARGAIN Larry Steckler Fordham CV4 publisher Arline Fishman HUNTERS CORNER Grantham College 58 advertising director Jim Wharton Christina Estrada JDR's VP Sales 181 Heath Instruments 3 advertising assistant Lisa Strassman DFI SERIAL $3995 86 Heathkit 32 credit manager MOUSE AND 178 International Components Corp.. 94 SALES OFFICES HALO-DPE SOFTWARE EAST/SOUTHEAST 183 ICS 76 Stanley Levitan REGULARLY $59.95 Eastern Sales Manager THREE -BUTTON OPTO -MECHANICAL MOUSE 113,170 JDR Microdevices 104, 105 Radio -Electronics 200 DPI RESOLUTION 259-23 57th Avenue USES SERIAL PORT 2 COM1 OR COM Little COMPATIBLE WITH MICROSOFT MOUSE AND PC 113,170 JDR Microdevices 106 Neck, NY 11362 MOUSE 1-718-428-6037, 1-516-293-3000 INCLUDES SOFTWARE MOUSE DRIVERS 114 Jameco 98 5-1/2 FT. CABLE WITH FEMALE DB25 CONNECTOR MIDWEST/Texas/ INCLUDES HALO-DPE SOFTWARE, A SOPHISTICATED Arkansas/Okla. DESKTOP PUBLISHING EDITOR 115 Jensen Tools 75 IMAGE EDITOR UTILITY PERMITS 90° ROTATION AND Ralph Bergen ABILITY TO SAVE IN WINDOWS, GEM, HALO AND PC Midwest Sales Manager 184 PAINTBRUSH FORMATS Jinco Computers 96 Radio -Electronics DON'T MISS THIS GREAT VALUE! 540 Frontage Road-Suite 339 DMS -200 EXPIRES 10/31/89 King Wholesalers 80 Northfield, IL 60093 1-312-446-1444 87 MCM Electronics 95 Fax 1-312-446-8451 JDR Microdevices 53 MD Electronics 94 PACIFIC COAST/ 2233 BRANHAM LANE, SAN JOSE, CA 95124 Mountain States * 93 Mark V. Electronics 103 Marvin Green Pacific Sales Manager ORDER TOLL -FREE 63 Micro -Mart 95 Radio -Electronics 5430 Van Nuys Blvd. Suite 316 61 Microprocessors Unitd 85 Van Nuys, CA 91401 800-538-5000 1-818-986-2001 LOCAL (408) 559-1200 FAX(408)559-0250 TELEX 171-110 190 Movietime 28 Fax 1-818-986-2009 CIRCLE 113 ON FREE INFORMATION CARD 106 DEALERS CIRCLE 170 ON FREE INFORMATION CARD

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$1995

Dynamically Analyze Stereo Audio Power Amplifiers To A Full 500 Watts To IHF/EIA * Specifications In Less Than 1/2 The Time It Now Takes

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Left Channel Introducing the "Missing Link In Audio Servicing," with the NEW PA81 Stereo Power A. Amplifier Analyzer'', from Sencore Electronics. The PA81 provides everything you need PA81 Stereo AM -FM, Power Amp Direct Coupled HI Watt for power amplifier analyzing integrated into one complete package, with: TV, Tape, Av... Preamps & Load Or Or CD (Audio Drivers B. Line) Power Am Speaker Twin Frequency Compensated Autoranged Wattmeters: 250 watts per channel (500 watts if paralleled), and listen to audio clarity with built-in volume control. Built-in IHF/EIA Testing Components At Your Fingertips: 2,4,8,16, and 32 ohm -zero reactance loads, and all specified bandpass audio filters. Right Channel Measure RMS Volts And dB As You Trace Through Circuits: Plus, programmable dB to A. Stereo AM -FM, PA81 measure gain. Coupled Power Amp stage TV, Tape, Phono, Direct HI Watt Damage: Built-in DC balance test, automatically Preamps & Load Or Test Intermittents To Prevent Amplifier Or CD (Audio V B. Line) V Drivers 1."" Speaker opens loads. Power Amp Test Audio Line Levels To Make Sure The Driver Input Signal Is Correct: Check turntables, AM tuners, FM tuners, TV stereo demodulator outputs, CD players, etc. for Walk troubles out of any power amplifier stage, step by step, with the PÁ81. standard line levels. Monitor Stereo Separation To 126 dB: Monitor, troubleshoot, or align AM -FM or TV Stereo separation circuits.

Call 1-800- SENCORE Ask About CQR r36-26731 S¡V A 10 Day 3200 Sencore Drive, Sioux Falls, South Dakota 57107 In Canada Call 1-800-851-8866 Video Preview IHF-Institute Of High Fidelity EIA-Electronics Industries Association CIRCLE 180 ON FREE INFORMATION CARD

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B&K SCOPE 31/2 Digit SCOPE Han:Held SCOPE Pocket Size Precision Test Bench" Muttimeter LCD Mini Meter 31 Digit LCR Meter Aida Signal Generator 41 range voltmeter Ammeter 11 function, 38 ranges including: 0.5% accuracy ACIDC Voltage Measure capacitance resistance Sine/square wave patterns 20Hz Ohmmeter Frequency counter Logic Level Detector, Audible and DC current Resistance Diode and induction Overload to 150 KHz Battery operated Capacitance meter Logic probe Visual Continuity, Capacitance & test 300 hrs battery life protection Includes test leads test Frequency accuracy ±3% (or less) Transistor & diode tester Extra - Conductance measurements Overload protection: DC -500V, clips, 9V battery and spare fuse Output 1.2V rms max. (no load)

large LCD display AC -350V, ohms - 250V DC/AC Low battery indicator Test leads & 9V battery included Model Model Model Model Moss DVM638 OVM-630 $7995 MM -680 RC -555 $5995 Reg. $129.95 $11900 Reg. $87.50 Reg. $50.00 Reg. 569.95 DUAL TRACE OSCILLOSCOPES

A.W. SPERRY 20 MHZ HITACHI 35 MHz OSCILLOSCOPE OSCILLOSCOPE Built-in component checker 19 calibrated sweeps 6" Z-axis input Low power CRT with internal graticule, consumption TV Video sync scale illumination & photo- filter High -sensitivity X -Y mode graphic bezel Auto focus Front panel trace rotator X -Y operation TV sinc Includes 2 test probes separation Includes 2 probes (10:1 and 1:11 Model $34e5 Model V-355 620C Reg. S899.95 5 TRAINERS AND TOOLS

SCOPE DIGITAL ALL PURPOSE TRAINER 92-PC. TOOL CASE ]IGITAL TRAINER Learn logic circuits and Complete kit for home, equipment design Connects workshop and auto Includes to oscilloscopes, signal 52 -pc socket set with extenders generators and more Logic 2 tool pallets with roomy probe included Solderless rear storage compartments breadboard and chb sheets help Attractive, rugged carry case you build almost any circuit Model FTK-28 Runs off 4 "M" batteries or AC adapter (included) Reg. $169.95

ModDeiel $ $12995 Reg. 5149.95

ASK FOR YOUR FREE CATALOG Service & Shipping Charge Schedule Continental U.S.A. FOR ORDERS ADO TOLL $25-50 $450 $5,-100 $6.50 FREE MO 800645951 $301-000 $900 Fordham $401-500 $5000 (In NY State 800-8321446) $501-750... $1250 $751-1000. .. $1600 260 Motor Parkway Money orders, checks accepted $1001-1.250 $1750 $1251-1500 $2000 Hauppauge, New York 11788 5-s C.O.D's require 25% deposit. $1ÁS$2 and Up $3Ó00