POPULAR ELECTRONICS, May 1980

o:uar. e tunics WORLD'S LARGEST- SELLING ELECTRONICS MAGAZINE MAY 1980/ 950 Build A Super Intrusion Alarm SENSES MOVEMENT AT A DISTANCE How Far Did You Cycle Today? ELECTRONIC DEVICE MEASURES MILEAGE Experimenting With Sound -Effect Circuits or 11 Game!

NewTrdfrling - Course: How to Use Mi.croprócessors in iYour OWn. Circúits

I 1 I ///. '14 Fg` S L If; _ _ )F°. i F...t_' '` / as 3 =r - .

. - \.af,' S !- I. : _S. = - _..- ;y;.Y_ -_.t 11016 1] .. 0I1í3d117 _ - b4 ÁW OS19 ar 1135)100 1 Tested Elec 0 ' 19134 4111 1101i0;11 SINS 260OE In This Nag ' Ti 14024 14278 Issue: Audio Control Spectrum Popula Electronics Analyzer/Equalizer

AmericanRadioHistory.Com

CIRCLE NO.6 ON FREE INFORMATION CARD

AmericanRadioHistory.Com NEW INVENTION

A new space-age invention and the same effect as lightning combine to create the world's first home oxygen regeneration system.

The new Energaire ionized oxygen generator will make a handsome addition to any desk.

You need oxygen to live. You can live put a large piece of paper on the wall. Within a We are so impressed with the pleasant without food for 60 days, without water for few days notice how black the paper gets.That effect of Energaire that we urge you to per- seven days, but without oxygen, you won't black film is finite carbon particulate matter- sonally test it yourself in your home or office. make it past two minutes. the same pollutants you would normally Order one at no obligation. Put it by your desk, That small piece of fuzz located on top of the breathe and that would pass through most air or in any room where you spend a great deal of cylinder shown above emits negatively - filters. By placing the unit in the center of a time. See if it doesn't rid your room of odor - charged electrons which attach themselves to room or away from a wall, that same matter causing bacteria and stale, musty or smoky molecules of oxygen, thus creating ionized falls to the ground as dust. air. Try the smoke and paper tests mentioned oxygen. A trip into the mountains exposes you to in this advertisement. You are already familiar with ionized oxygen nature's freshly ionized oxygen. The Ener- SLEEP FASTER gaire produces this same effect. It will clean if you've smelled the air after a thunderstorm. At home, use the Energaire by your bed and light- your room of odor -causing bacteria and stale, You feel great, revitalized, and alert. The see how country -fresh air allows you, to sleep - musty, or smoky air. ning from the storm adds a small negatively easier, deeper, and more relaxed. electron to each oxygen molecule in a Ionized oxygen should not be ccnfused with charged You should notice the difference within one process called ionization. ozone. Ozone has a molecular formula of 03, day-especially in a work environment. But whereas the molecular formula for ionized SCIENTISTS DISCOVER use the Energaire for a full month. Then, if you oxygen is 02 with a negatively -charged ion. Scientists discovered that air quality can do not feel totally convinced of the positive actually affect your moods, your feelings and DON'T BE CONFUSED effects of ionized oxygen, return your unit for a your sense of well being. Air that is positively After we announced the Energaire last year, prompt and courteous refund. charged caused people to be depressed, many companies came out with their own ion The Energaire is manufactured by the Ion moody and tired. Negatively -charged air made generators. We purchased a unit from each Foundation, a leading ion research and devel- people feel good. We have all experienced air company and tested them at an independent opment company. that is positively charged in air-conditioned laboratory. The results are shown below: Service should never be required, but if it is, buildings or in a polluted environment. there's a prompt" service -by -mail center as Scientists looking for a way to turn positively close as your mailbox. JS&A is America's charged air into negatively charged air devel- largest single source of space-age products oped the negative ion generator-a product Name *Ins Price further assurance that your modest invest- that produces negatively charged particles Energaire 438,000 $79.95 ment is well protected. The Energaire mea- that attach themselves to .air molecules and Omega 700 63,000 245.00 sures 9" high by 3" in diameter and weighs 24 thus create the same fresh feeling you get AirCare 72,000 149.95 ounces. after a thunderstorm. To order your Energaire ionized oxygen The new space-age product shown above is Modulion 75,000 79.95 generator, send $79.95 plus $3.00 for postage an ionized oxygen generator called the *Measurements indicate total number of ions and handling (Illinois residents, please add 5% Energaire air purifier. The copper mesh fuzz per cubic centimeter per second at one sales tax) to the address shown below or credit on top of the unit is one of the secrets of the meter. These figures may vary by plus or card buyers may call our toll -free number system. minus 10%. below. We will send your Energaire ion Although it has no moving parts, you can Note: One unit not mentioned above pro- generator complete with 90 -day limited duced no ions and actually produced ozone actually feel a wind of ionized oxygen pro- warranty on the electronics, a five-year or several times the maximum ozone concen- duced from the fuzz .which spreads to fill an tration allowed by federal government warranty on the fuzz, and complete in- average -sized room in one minute. standards. structions. CIGARETTE SMOKE TEST Let space-age technology revitalize your life To show the dramatic effect of ionized with the world's first home ionized oxygen USED IN HOSPITALS no today. oxygen, you take the Energaire, blow generator. Order one at obligation can Many hospitals are now using ionized cigarette smoke into a clear bowl, and hold the oxygen systems in their operating rooms and inverted the system. The smoke will bowl over burn centers. Their units not only purify the air, vanish. The charged oxygen particles appear but they also eliminate pollen and other particles, precipitating to dissolve the smoke irritants. O PRODUCTS them from the air. Working in a clean air environment, you In a room, the Energaire air purifier sur- think clearer, are more alert, and you function rounds you with these oxygen ions and cleans ® TE:iTHINK better. The Energaire is actually a miniature 0 and purifies the air so that even in a smoke - lightning machine. The minute you plug it in, Dept. PE One JS&A Plaza filled room, you will be breathing cleaner, energy is converted into ionized oxygen. This Northbrook, III. 60062 (312) 564-7000 country -fresh air all day long. efficient system uses one watt of power or less Call TOLL -FREE 800 323-6400 WALL TEST than a penny per day to operate, so you leave In Illinois Call (312) 564-7000 Take our unit and place it next to a wall. Also it plugged in continuously. ©JS&A Group, Inc.,1980

POPULAR ELECTRONICS 1

AmericanRadioHistory.Com .` t

.l t'L t- SS . 7 .4 ... "" ....

- C: N,' t f n ri ci ta - .. .aa ==. - ilei

The easiest, least expensive way to generate spectacular multi -color graphics, sharp two-color alphanumerics: Your computer, a color tv set and the Percom Electric Crayon: Add the Electric CrayonTM to your adapted for interfacing to any Options include: system and your keyboard be- computer or to an ordinary parallel LEVEL II BASIC color comes a palette, the tv screen ASCII keyboard. graphics programs on your medium. minidiskette: $17.95. You dab and stroke using one - But that's not all A 34 -conductor ribbon key commands to create dazzling The Electric Crayon is not just a cable to interconnect the Elec- full -color drawings, eye-catching color graphics generator/control- tric CrayonTM to a TRS-80*: charts and diagrams. ler. $24.95. Or you run any of innumerable It is also a complete self- RAM chips for adding re- programs. Your own BASIC lan- contained control computer. With fresh memory for higher den- guage programs that generate built-in provision for 1K -byte of sity graphics modes: $29.95 dynamic pyrotechnic images, on -board program RAM, an per K -byte. laugh -provoking animations. EPROM chip for extending EGOSTM Electric CrayonTM From a combined alphanu- its on -board ROM graphics OS, Sketchpad, a sketching grid merics-semigraphics mode to a proportioned. and a dual bidirectional eight -bit of picture ele- high resolution 256- in by 192-, port - over and above the comments (pixels) a tv aspect element full graphics mode, the port for ratio. For 128 x 192 or 256 x microprocessor -controlled puter/keyboard - Electric peripherals. The applications are 192 graphics modes. 11 -inch Crayon?M is capable of generating by 17 -inch, 25 -sheet pads: 10 distinctly different display endless. $3.95 per pad. modes. with EGOSTM, -byte Shipped 1K of SYSTEM REQUIREMENTS: the video cir- Colors are brilliant and true, and display memory and a com- cuitry of the Electric CrayonTM provides di- up to eight are available depend- prehensive user's manual that in- rect drive input to a video monitor or mod- ing on the mode. cludes an assembly language list- ified tv set. An internal up -modulator for rf As antenna input may be constructed by add- shipped, the Electric ing of EGOSTM and listings of ing inexpensive components to the existing CrayonTM interfaces a TRS-80* BASIC demo programs, the Elec- video circuitry. computer. It may be easily tric CrayonTM costs only $249.95. Prices and specifications subject to change without notice.

= trademark of Percom Data Company, Inc. = trademark of Tandy Radio Shack Corporation which has no relationship to Percom Data Company. PERCOM Get into computer color graphics the easy, low-cost way with a Per - corn Electric CrayonTM. Available. at Percom dealers nationwide. Call PERCOM DATA COMPANY, INC. 211 N. KIRBY GARLAND. TEXAS 75042 toll -free, 1-800-527-1592, for the address of your nearest dealer, 1214/ 272.3421 or to direct if is no Percom dealer in your area. 2 order there MAY 1980 CIRCLE NO.57 ON FREE INFORMATION CARD

AmericanRadioHistory.Com MAY 1980 Popular VOLUME 17, NUMBER 5 WORLD'S LARGEST -SELLING ELECTRONICS MAGAZINE Feature Articles

MICROPROCESSOR APPLICATIONS FOR THE 1980's ... IT'S A WHOLE NEW BALL GAME! /George Meyerle 41

Part 1 of a series devoted to learning how to use inexpensive microprocessors in custom applications. CLEAR -CHANNEL AM STANDARD BROADCAST STATIONS 93 COMPUTER CLUB DIRECTORY/PE Staff 96

Construction Articles - HIGH PERFORMANCE "SCRATCH AND RUMBLE" FILTERS/John H. Roberts 50 Low-cost active filters add high performance to your audio components. BUILD "LIDITH"-A 31/2 -DIGIT LCD DIGITAL THERMOMETER/Tom Fox 55 .91i 4k r *e.. Precision digital thermometer measures from -30° to +199°F. BUILD A MOTION -DETECTOR ALARM/Walter Gontowski Jr. 61 About the cover: System has optical sensors that can detect intruders as well as smoke or fire. HOW FAR DID YOU CYCLE TODAY?/Arthur V. Clark 71 The microprocessor Inexpensive odometer indicates distance traveled in miles on a three -decade be in a can used myriad LCD readout. Qf applications other than for computers, EXPERIMENTING WITH A SOUND -EFFECTS GENERATOR/Frank I. Gilpin 77 which is detailed Create a multitude of sounds with a single chip in the lead article REVERSE IC SOCKET/Gene Nelson 93 of this issue. Home-brew adapter simplifies correcting mirror-image wiring errors.

Cover photo by Don Carros Columns - -- STEREO SCENE/Harold A. Rodgers 21 Domestic Harmony.

JOE MESICS HOBBY SCENE/John J. McVeigh 83 Publisher EXPERIMENTER'S CORNER/Forrest M. Mims 84

Optical Fiber Communications, Part 1. ARTHUR P. SALSBERG Editorial Director DX LISTENING/Glenn Hauser 88 Wider Bands for Shortwave Broadcasting. HAROLD A. RODGERS COMPUTER BITS/Hal Chamberlin 94 Editor Executive Electrical Noise. LESLIE SOLOMON SOFTWARE SOURCES/Leslie Solomon 100 Technical Director PROJECT OF THE MONTH/Forrest M. Mims 103 JOHN R. RIGGS Light -Wave Voice Communicator. Managing Editor

EDWARD I. BUXBAUM Julian Hirsch Audio Reports Art Director AUDIO CONTROL MODEL C-101 GRAPHIC EQUALIZER AND SPECTRUM ANALYZER 31 ALEXANDER W. BURAWA Feature., Editor ELECTRO -VOICE MODEL INTERFACE: 2 SERIES II SPEAKER SYSTEM 34

JOHN J. McVEIGH NAGATRONICS MODEL 350E STEREO PHONO CARTRIDGE 36 Technical Editor

ANDRE DUZANT Departments M1 Technical Illustrator EDITORIAL/Art Salsberg 4 CARMEN ROBLES Where Are You Going In Electronics? Production Editor LETTERS 6 JEFF NEWMAN Editorial Assistant OUT OF TUNE 6 NEW PRODUCTS 8 Contributingtributing Editors Hal Chamberlin, Lee Felsensteln NEW LITERATURE 14 Glenn Hauser, Julian Hirsch, Forrest Mims ELECTRONICS LIBRARY 104 LINDA BLUM OPERATION ASSIST 1 13 Advertising Service .tlurrager ADVERTISERS INDEX 115 MARIE MAESTRI Executive Assistant PERSONAL ELECTRONICS NEWS 1 20

EDGAR W. HOPPER POPULAR ELECTRONICS (ISSN 0032-4485): Published monthly by Ziff -Davis Publishing Company, at One Park Avenue. New York. Publishing Director NY 10016. Philip B. Korsant, President: Selwyn Taubman, Treasurer; Bertram A. Abrams, Secretary. One year subscription. U.S. and Possessions, $14.00; Canada, $17.00; all other countries, $19.00, cash orders only, payable in U.S. currency. COPYRIGHT 1980 BY ZIFF-DAVIS PUBLISHING COMPANY. ALL RIGHTS RESERVED.

MAY 1980 3

AmericanRadioHistory.Com Popular Electronics

ZIFF.DAVIS PUBLISHING COMPANY Editorial and Executive Offices One Park Avenue, New York, New York 10016 212.725.3500 Joseph E. Mesics Publisher (725-3568) Richard F. Govatski Editorial Advertising Manager (725-3939) Bonnie B. Kaiser Eastern Adv. Mg., (7253580) Midwestern Office Ted Welch Suite 1400, 180 N. Michigan Ave., Chicago, IL 60601 (312.346.2600) WHERE ARE YOU GOING IN ELECTRONICS? Western Office 3460 Wilshire Blvd., Los Angeles, CA 90054 213-3872100 Some weeks ago I turned on my TV receiver and, surprisingly, viewed part of Western Representative: Norm Schindler a Jon Marshall program that explored the solid-state industry in that wondrous North Califor- 7050 Owensmouth Ave., 8209 nia area called "Silicon Valley." An interview with a computer specialist re- Canoga Park, CA 91303 (213.999.1414) Japan: James Yagi. Oil Palace Aoyama; vealed that there's virtually a price war going on for skilled electronics people. 6.25. Minami Aoyama. 6 Chome, Minato-Ku, Times are obviously good for electronics -trained personnel, but will it continue? Tokyo, 407-1930(6821, 582-2851 All indications are that the need for skilled people in the field of electronics ZIFF-DAVIS PUBLISHING COMPANY Philip B. Korsanl, President will grow in this new decade. For example, the U.S. Department of Labor re- Furman Hebb, Executive Vice President cently indicated that computer Phillip T. Heffernan, Sr. Vice President technician jobs are expected to double in the Edward D. Muhlleld, Sr. Vice President next ten years. And an Intel executive predicts that we'll need more than one - Philip Sine, Sr. Vice President, Lawrence Sporn, Vice President, Circulation and Marketing million software engineers by 1990, while our education system is producing Richard Friese, Sr. Vice President only tens of thousands each year. Baird Davis. Vice President, Production George Morrissey, Vice President Entry-level salaries for techs are reported to be over $20,000 per year in- Sidney Holtz, Vice President cluding overtime, while some experienced techs earn $35,000. Engineers, too, Albert S. Traína, Vice President Paul H. Chook, Vice President are having a field day. For example, June 1979 electrical engineering graduates Edgar W. Hopper, Vice President (bachelor's degrees) from MIT yearly Robert N. Sevier, Jr., Vice President received starting salaries that ranged from Selwyn Taubman, Treasurer $17,640 to $21,780; computer science grads got $17,000 to $22,000. With a Bertram A. Abrams, Secretary master's, the range was said to be $18,480 to $24,420. And I know an MIT W. Bradford Briggs, Vice Chairman grad who earned his doctorate at that time and his first job started at $30,000. There's a minor furor going on about who's an electronics engineer. As many ZIFF CORPORATION William Ziff, Chairman readers may know, there's an EE degree and a BET degree, the latter being a I. Martin Pompadur, President Bachelor of Engineering Technology. In Hershel B. Sarbm, Executive Vice President trying to distinguish between the two, some people have suggested that the EE is really a theoretical engineer upon

POPULAR ELECTRONICS, May 1980. Volume 17, Number graduation, while the BET is an applied engineer. Moreover, it has been pointed 5 Published monthly at One Park Avenue, New York, NY out that the EE course is really a five-year one, though often completed in four 10016. One year subscription rate for U.S. and Possessions. 514.00: Canada. 517 00: all other countries, $19.00 (cash years by handling heavy course loads, while the BET curriculum is for four orders only, payable in U.S. currency). Application to mail at years. Consequently, some EE's are battling BET's for the same controlled circulation postage rates is pending at Salem. jobs. There are Illinois 62881. Authorized as second class mail by the Post also many techs who are doing engineering work and, indeed, are considered to Office Department. Ottawa. Canada, and for payment of be postage in cash. engineers and paid accordingly. POPULAR ELECTRONICS including ELECTRONICS There are a lot of training avenues available to one who wishes to enter or WORLD, Trade Mark Registered. Indexed in the Reader's guide to Periodical Literature. grow in the electronics field: home study courses, seminars, technical institutes, COPYRIGHT 1980 BY ZIFF-DAVIS PUBLISHING COMP A. and colleges, among others. There's also POPULAR ELECTRONICS, which in this is- NY, ALL RIGHTS RESERVED. Ziff -Davis also publishes Boating, Car and Driver, Cycle. sue presents a first -of -a -series microprocessor applications training course. Flying, Popular Photography, Skiing, Stereo Review. Elec. With more and more circuit designs that dedicate microprocessor IC's for ironic Experimenter's Handbook, Tape Recording 8 Buying Guide. Stereo Directory 8 Buying Guide, and Communice noncomputer end products-telephone answering machines, electronic games, tions Handbook. "smart" thermostats, etc.-it's imperative that readers understand how to use Editorial correspondence: POPULAR ELECTRONICS, I Park Ave., New York, NY 10016. Editorial contributions must microprocessors to create low-cost sophisticated circuits. Moreover, this un- be accompanied by return postage and will be handled with derlying knowledge will prepare you to service the ever-growing number of mi- reasonable care: however, publisher assumes no responsi- bility for return of safety of manuscripts, art work, or mod- croprocessor -based products and provide you with a solid foundation to under- els submitted. stand computers, computer programming, and how to make a computer interact Forms 3579 and all subscription correspondence; POPULAR ELECTRONICS, Circulation Dept. P.O. Box 2774, with the outside world for, say, a super security system. Boulder, CO 80302 Please allow at least eight weeks for What's more, all this know-how will open new electronics vistas for the enthu- change of address. Include your old address, enclosing, if possible. an address label from a recent issue. siast, many of whom are involved professionally in electronics. It means that Permissions. Materials in this publication may not be electronics can be more exciting and fulfilling than ever before. reproduced in any form without permission. Requests for permission should be directed to Jerry Schneider. Rights end Permissions, Ziff -Davis Publishing Co., One Park Ave., New York, NY 10016.

The publisher has no knowledge of any proprietary rights which will be violated by the making or using of any items disclosed in this issue. MPA

Member Audit Bureau of Circulations

4 POPULAR ELECTRONICS

AmericanRadioHistory.Com The Personal Computer Line by OHIO SCIENTIFIC Personal Computers Cl P: $349 A dramatic breakthrough in price and performance. Features OSI's ultra -fast BASIC -in -ROM, full graphics display capability, and large library of software on cassette and disk, including entertainment programs, personal finance, small business, and home applications. It's a complete programmable computer system ready to go. Just plug-in a video monitor or TV through an RF converter, and be up and running. 1! 15K total memory including 8K BASIC and 4K RAM-expandable to 8K. c11nv1016 Cl P MF: $995 First floppy disk based computer for under $1000! Same great features as the C113 plus more memory and instant program and data retrieval. Can be expanded to 32K static RAM and a second mini -floppy. It also supports a printer, modem, real time clock, and AC remote interface, as well as OS -65D V3.0 development disk operating system. ,, Professional Portables C4P: $698 The professional portable that has over three times the display capability of Cl Ps. Features 32 x 64 character display in up to 16 colors, graphics, audio output, a DAC for voice and music generation, key pad and joystick interfaces, AC remote control interface and much more. Utilizes a 4 -slot BUS (2 used in base machine), 8K BASIC -in - NMI ROM, 8K of static RAM and audio cassette interface. Can be directly expanded to 32K static RAM and two mini -floppy disks.

C4P MF: $1695 The ultimate portable computer has all the features.of the C4P plus real time clock, home security system interface, modem interface, printer interface, 16 parallel lines and an accessory BUS. The standard machine operates at twice the speed of currently available personal computers (with GT option it runs even faster!). The C4P MF starts with 24K RAM and a single mini -floppy and can be directly expanded to 48K and two mini -floppies. Available software includes games, personal, business, educational and home control applications programs as well as a real time operating system, word processor and a Computers come with keyboards and floppies where specdied. data base management system. Other equipment shown is optional. Home/Small Business Systems C8P DF: From $2597 The ultimate Home/Very Small Business Computer at a C8P: $895 Same great features as the C4P in a tremendously expandable "main- personal computer price. Features 32K RAM frame package" Features over three times the expansion capability of the C4P for (expandable to 48K) and dual 8" floppy disks advanced home and demanding business applications. Can be expanded to 48K RAM, (stores eight times as much information as a dual 8" floppies, hard (Winchester) disks and multiple I/0 devices such as Voice I/O and mini -floppy). Has all .personal computer a universal telephone interface. capabilities including 32 x 64 display, color graphics, sound, DAC, joystick interfaces, home features including real time clock, AC remote interface, home security and fire detection interface and can be expanded to include voice I/O and a universal telephone system for answering and initiating calls! Its large memory capability and 8" floppies allow it to run most Ohio Scientific business system au.esV Y software including a compete accounting - yll-..,s. //f{ system, word processor and information /i* management system. --; .: For Iiiterature and the name of your local J dealer, CALL 1.800.321.6850 TOLL FREE.

J , .-- OHIO SCIENTIFIC CIRCLE NO.45 ON FREE INFORMATION CARD 1333 SOUTH CHILLICOTHE ROAD AURORA, OH 44202 (216] 831-5600

AmericanRadioHistory.Com worldwide station listings was a frustrating kHz?" in the same issue. I have been waiting

experience. Your listings ,(as in December for something like this since I picked up a

1979) turned the tables! I suddenly discov- BC -453 receiver at last fall's local hamfest.- ered I`could ambush any station by referring Alan Bosch, Arlington, VA. to your listing of English broadcasts. The updating in January further improved the situ- A SIMPLER 3D SOLUTION ation and then your February listing of select- The 3D Resistor Quiz in the September ed shortwave programs came very close to 1979 issue reminded me of a problem I once giving me an adrenalin surge.-S. F. Metz, gave my physics students. However, author Derry, NH. Gary Seaver uses some parallel and series Letters assumptions in his solution that I have trouble Someone merits a bogus for coming up justifying. Below is a simpler solution using with "Selected Shortwave Programs" (Febru- ary 1980). The time/topic approach is imagi- THANKS FROM SHORTWAVE FANS native, intriguing, and handy. It's like having a As a very recent convert to the pleasures TV Guide to shortwave. Another compliment of shortwave listening, I found the use of is deserved for "What's on the Air Below 500

Kirchoff's laws with no justification problems. It is not necessary to consider all the resis-

tors-only the seven I have labelled in my diagram. To determine resistance between X and Y, connect a battery, rheostat, and ammeter as shown. Adjust the rheostat for a 3 -ampere reading on the ammeter. Now, applying Kir- choff's first law (the sum of currents arriving at a junction equals the sum of currents leav-

ing the junction), R1, R2, and R3 conduct 1 ampere each; R4 and R5 conduct 0.5

ampere; and R6 and R7 conduct 1 ampere. Using Kirchoff's second law (in any loop, the voltage rises equal the voltage drops), the drop across RI is 100 volts, across R4 equals 50 volts, and across R6 equals 100 Cat. volts. Therefore, considering R1, R4, and R6 as a complete loop, the sum of the drops is Someday there 250 volts. Finally, applying Ohm's Law, we get R = E/I = 250 V/3 A = 83.3 ohms. won't be a phone -Park E. Gregory, Belleville, Ml. COMPUTER ACCURACY

I understand the consternation on the without one. Fast, accurate, reliable-and only $189. man's face in Cat. Someday there the computer cartoon on page 87 of The only way to realize the full potential won't be a computer your March 1980 issue. A total of 3.999 of your small business or personal com- without one. from adding 2 + 2 is not 99.999% accuracy, puter is to tie it in with other computers. but only 99.9975% accuracy-R. N. Tomlin, ' I And the best way to do that is with a Cat Ann Arbor, MI. acoustic modem. A Cat modem lets your computer talk RA DIATION INFORMATION face to face with any other compatible ovaatby tion I agree with Peter L. Schestopol's letter in computer or terminal within Tie your reach of computer into the world. your March 1980 issue that there is too much your phone, over standard telephone Call for details lines. misinformation being fed to the public about You can work at home using the com- radiation. Unfortunately, some of his informa- puter at your office. Send or receive data (800) 423-5410 tion is incorrect. from anywhere. Or swap programs. In California (213) 996-5060 First, the rad, the unit of absorbed dose, is not 1 erg per gram but is 100 ergs per gram in Available at Hamilton/Avnet, Kierulff Electronics, Byte Shops, Computerland, the C.G.S. In the S. I. units, it and your local computer store. system. 0.01 joules per kilogram. Novation, Inc., 18664 Oxnard Street, Tarzana, California 91356 Second, the roentgen is 0.000258 'cou- FREE 6 CIRCLE NO.44 ON INFORMATION CARD POPULAR ELECTRONICS

AmericanRadioHistory.Com lombs per kilogram of air in S. I. units. In C. G. S, it is the amount of radiation required to produce 1 electrostatic unit of charge per cubic centimeter of air.-J. Wesley Kersey, Memphis, TN.

SOLVING LISSAJOUS PATTERNS In regard to the "Lissajous Pattern Quiz" (January 1980), finding the ratios can be tedious if you follow the trace and try to remember where you've been, where you're going and how many times you've 8W-2630 gone up and down and left and right and-now where 'was I? The task can be made easy by remembering that each time the trace moves from one edge of the screen to the other (half a cycle), it attery Tool must cross the axis. Thus, if one draws the two major axes and counts intersections, the ratio is: vertical frequency/horizontal frequency = horizontal axis intersections/vertical axis intersections,-D. J. Kos- cheka and N. D. Herbert, Palatine, IL 60067.

PROTECTING A LONGWAVE CONVERTER

I enjoyed the two-part article by Karl Thurber "What's on the Air

Blow 500 kHz?" (February and March 1980). I particularly noted the authors warning to anyone who uses a receiving converter on a transceiver to remove the mike in order not to transmit with the converter attached, thus avoiding damaging the converter. On my ham rig, I have been using a 6 -meter Venus transceiver to drive a home- brew, 2 -meter transverter. I broke the wire in the transceiver that runs from the receiver's antenna coil to the switching relay and installed two jacks in this line. Then, when I want to use my 2 -meter transverter,

I plug the output of the receiving converter section into the jack going to the antenna coil. This way I can't transmit and damage the converter. To use the transceiver on 6 meters, I simply disconñect the output of the receiving converter from the receiver input stage and run a jumper across the jacks.-H. D. Mohr, Gahanna, OH.

SUBSTITUTE FOR LM1890 IN SUNDIAL It has come to our attention that the LM1890 light -to -current converter used in the "Solar Powered Sundial" (March 1980) is in short supply since it is no longer in production. The circuit below, using conventional light-sensitive transistors and a dual comparator, can be substituted easily for the LM1890 circuit.-Ed. +v BW- 2630 $19.85* BT -30 ,$ 3.95* BT -2628 $ 7.95* TO R3,CI

DUAL COMPARATOR BW-2630 BATTERY TOOL To The new BW-2630 is a revolutionary battery R4,C2 tool. The tool operates K powered wire -wrapping on 2 standard "C" size NiCad batteries (not included) and accepts either of two specially designed bits. Bit model BT -30 is for wrapping 30 AWG wire onto .025" square pins ; BT -2628 wraps 26-28 AWG wire: Both produce the preferred "modified" wrap. Designed for the serious amateur, BW-2630 even includes both positive indexing and anti-overwrapping mechanisms - features usually found only in industrial tools costing five times as much. Pistol grip design and rugged ABS construction assure performance -1_ and durability. In stock at local electrcnic retailers or directly from Out of Tune OK Machine & Tool Corporation 3455 Conner St., Bronx,N.Y. 10475 U.S.A. Tel. (212), 994-6600 Telex 125091 The schematic of the power supply for "A 3 -Way Drive System for -Minimum billings S25.00, add shipping charge 52.00 Speakers" shown as Fig. 2 on page 48 of the April 1980 issue shows New York State reside nts add applicable tax ' the positive output of fullwave bridge RECT1 incorrctly connected to one of its ac inputs. The etching and drilling and parts placement guides are correct. CARD CIRCLE NO.48 ON FREE INFORMATION 1 MAY 1980

AmericanRadioHistory.Com warped records, as well as the ability to Logic interlace well with low -capacitance turnta- -Controlled ble wiring and preamp inputs. Frequency Cassette Deck response is rated at 20 to 28,000 Hz ± 1314 dB, with a recommended tracking force of Aiwa's AD-M700BU (black finish) and its 1.5 grams. Vertical tracking angle is 20°, sister unit, AD -M7000 (silver finish), are and the unit is designed to feed an input designed to use metal, Cr02, FeCr, and LH rated at 47 kilohms in parallel with 150 pF. tape types. A bias fine adjustment control Price is $175. New Products CIRCLE NO. 88 ON FREE INFORMATION CARD 1 = Additional information on new products covered in this '; .6 section is available from the Sports Radar á' manufacturers. Either circle the item's code _ --- number on the Free Information Card Midex is now making available its Sports :°--___ or write to the manufacturer at the Radar, a handheld, lightweight (38.4 oz) address given. radar "gun" that can be used to measure allows optimum response from each. The and record the speed of tennis, golf, soc- decks have V -cut Sendust record/playback combination heads and double -gap ferrite erase heads. Other features include Hand -Held DMM a Double -Dolby circuit, a logic -controlled transport with . The Keithley Model 130 3"2 -digit LCD continuous repeat. operation as well as and hand-held digital multimeter features a start stop memory function, NIt X « and dual dc 0.6" -high LCD display, a 0.5% basic dc motors. Rounding out the pack- SPOrts podgy age is voltage accuracy, auto zero and polarity, a five -point LED peak indicator and a and full overload protection. There are five "rec-mute" function. Specifications include frequency response for metal tape at -20 VU recording level of 30 to 17,000 Hz +2, -3 dB; 25-12,500 Hz, +2,-3 dB at 0 VU; S/N 65 dB (FeCr tape, Dolby on), and wow and flutter of 0.04% (wrms). CIRCLE NO. 92 ON FREE INFORMATION CARD 1 Digital Inside /Outside cer and baseballs, hockey pucks,, human Vehicle or animal racers, RC planes, or almost any- Thermometer thing whose speed must be known. The The Heathkit CI -1525 Car Thermometer device will time from 20 to 150 mph. Oper- reads temperatures between -20° and ation is from a 12 dc voltage' ranges from 200 mV to 1 kV, -volt dc source. Frequen- + 140°F (-30° and +60°C) inside and is five -ac voltage ranges from 200 mV to 750 cy 10.525 GHz (X band) and an FCC outside any vehicle (including boats) with a volts, five ac and dc current ranges from 2 license is not required. $149.95. mA to 10 amperes and five resistance CIRCLE NO. 89 ON FREE INFORMATION CARD ranges from 200 ohms to 20 megohms. One hundred hours of life can be expected from the internal 9 -volt battery. A full line of accessories expands the Model 130 capa- CPU -Controlled Printer bilities to 40 kV, 200 amperes and voltage The Model 877 from Printer Terminal Com- at frequencies to 700 MHz. Dimensions are munications .Corp. is an 81(2" roll -paper 7" X 3.1" X 1.5" (18 X 8 X 4 cm). receive -only serial printer featuring bidirec- $99. tional 9 X 7 dot matrix head, hardened 12 -volt dc negative -ground system. The NO. CIRCLE 87 ON FREE INFORMATION CARD metal chassis and a stainless -steel drive 21'2 -digit fluorescent readout can be changed from Fahrenheit to Celsius and the indoor and outdoor readings can be High -Technology chosen separately or automatically alter- Phono Cartridge nated. It uses a dual -slope analog/digital converter. Accuracy is ±3%. $89.95 kit. Heading the new Dynamic Interface series CIRCLE NO. 90 ON FREE INFORMATION CARD of phono cartridges from Empire Scientific J is the model 600LAC. The unit uses a J vapored-boron, aluminum -alloy cantilever Dual-Trace, to improve tracking and to damp unwanted resonances. In addition, the cartridge fea- Delayed -Sweep tures samarium -cobalt magnets for high 30 -MHz Oscilloscope electrical output and lightweight construc- screw. A cartridge ribbon eliminates the tion that allows improved tracking of ribbon reversing mechanism. It prints at B&K-Precision's dual -trace Model 1530 os- 120 characters per second at 80 charac- cilloscope is said to have a 30 -MHz verti- ters per line, 10 characters per inch, and cal amplifier bandwidth, vertical R' sensitivity features a 95 -character ASCII set. The as low as 2 mV/cm, and delayed sweep paper roll is friction fed. The 877 includes over five ranges of time -base delay (1 as to an RS -232C interface with baud rates of 100 ms). Other features include variable 300 to 9600. Dimensions are 18" X 22" X hold -off, chopped or alternate dual -trace 7.5" (45.7 X 55.9 X 19.1 cm); weight is operation, differential measurement capa- 25 lb (11.36 kg) $999. bility, algebraic addition and subtraction of CIRCLE NO. 91 ON FREE INFORMATION CARD vertical input signals, X -Y display capabili-

8 POPULAR ELECTRONICS

AmericanRadioHistory.Com COMPUTER ERROR

JS&A was destined for failure Extended when we introduced our first electronic blood pressure unit. Lifespan But then a miracle happened.

Model 310

Advertisements were starting to appear an advertising campaign urging consumers to comes with each unit. everywhere. JS&A had just introduced the take their blood pressure regularly to combat The deluxe model 410 functions similar to world's first home electronic blood pressure hypertension or high blood pressure. Ads the first system except that the readings are unit in a massive national advertising cam- appeared everywhere. displayed in digits, and the unit also displays paign. The campaign revealed that there may be your pulse reading. It sells for $139.95 plus But something was strange. JS&A often as many as 25 million Americans who have $2.50 per unit for postage, insurance and tests its products in its catalog first before they high blood pressure and don't know it. Simply handling. If for any reason you are not com- are nationally advertised. If they sell well, we by taking their own blood pressure and dis- pletely satisfied with either unit, you may then start a national magazine advertising covering hypertension early enough, Ameri- return it within 30 days for a prompt and campaign. The blood pressure unit sold well in cans could be saving their lives and reducing courteous refund including your $2.50 post- our catalog, but for some strange reason, it the chances of heart attacks. Suddenly our age and handling. To order either unit, credit wasn't selling well in magazines. campaign started to sell blood pressure units card buyers may call our toll -free number, or by the thousands. may money order to SHOCKING DISCOVERY you send your check or the address below. And then we found the answer. A few AWARD RECEIVED Both units use solid-state components, months earlier after our blood pressure unit This year JS&A's president received the come complete with instructions and a one- appeared in our catalog, our computer man- Extended Lifespan award for "pioneering in limited warranty, and should give you ager (let us call him Ralph to protect his the distribution of home health electronic year years of trouble -free service. If service should identity) handed us a computer printout of the devices" by the Committee for an Extended be required, we maintain a service -by -mail catalog sales results. Lifespan. In accepting the award, our presi- center as close as your mailbox. JS&A is dent made it very clear that the award was Scanning the results, we discovered that the America's largest single source of space-age earned as a result of a computer error and not blood pressure unit was the best-selling products-further assurance that your modest as a result of his brilliance. product in our catalog-far exceeding every investment is well protected. other product by five times. This story is painfully true. And although it If you are concerned about your blood may be a slight embarrassment to us, there is The results were so positive that we pressure or know somebody who is concerned one aspect that is not. JS&A was indeed the immediately placed hundreds of thousands of about monitoring his or hers, we recommend company that pioneered the electronic blood dollars in an advertising campaign launched in JS&A's latest units. pressure units and has always selected the early 1978. Incidentally, Ralph left JS&A on his own very available to offer at the very Just as the advertisements were starting to best units lowest prices possible. accord and bought a farm in another state. appear, Ralph walked into our president's There were no hard feelings when he left. How office with some startling news. "There's been NEWEST UNIT could there be? Order your blood pressure unit a mistake," Ralph said. "The computer print- Our newest unit shown above is another at no obligation, today. out was wrong. The blood pressure unit is example. The model 310 sells for only $69.95 actually our worst selling product but a com- plus $2.50 for postage and handling (Illinois o PRODUCTS puter error gave us the wrong information." residents, please add 6% sales tax.) You sim- THAT And so our president sat back and watched ply wrap the velcro cuff around your arm (you ® JS&A advertisements appearing everywhere, can even keep your shirt on) and inflate the THINK® knowing full well that the campaign would cost cuff. Both an audible tone and a visible red Dept. PE One JS&A Plaza his company almost the price of a new light will indicate your systolic and diastolic Northbrook, III. 60062 (312) 564-7000 computer. readings. The system is extremely accurate, Call TOLL -FREE 800 323-6400 Then came the miracle. As if by plan, the comes with a self -bleeding air valve and can In Illinois Call (312) 564-7000 American Medical Association came out with be stored in a convenient carrying case that ©JS&A Group, Inc.,1980 9 POPULAR ELECTRONICS

AmericanRadioHistory.Com NEW PRODUCTS continued

(10.2 cm) wide, holds boards from 1" (2.5 cm) wide to 61/2" X 41/2" (16.6 X 11.5 cm). Standard Model 3 A/C ($12.50) is 53/4" (14.6 cm) wide, holds boards up to S-100 buss size. Maxi Model 3 C/C ($14.95) is 75/16" (18.5 cm) wide, holds boards such Intoz as those employed in single -board computers. The Extension Bench Clamp, two of which are required for use with the Maxi Model 3 C/C, is $4.95. "A-Technologica CIRCLE NO. 95 ON FREE INFORMATION CARD ty, built-in video sync separator, ac or Digitally Synthesized `Masterpiece :.:" direct coupling, intensity modulation provry sions, range of triggering choices (channel FM/AM Tuner A, channel B, alternate A and B, and ac power line, and an external source), and In addition to its automatic and manual X5 sweep magnification. Sweep rate can tuning modes, the new Akai AT-VO4 low- be varied from 0.2 µs /cm to 0.5 s/ cm. -profile stereo FM/AM tuner, with digital $1340. readout, has seven memory presets that CIRCLE NO. 93 ON FREE INFORMATION CARD .0oo©0.-0 Desk -Top Microcomputer

1 _ The iPEX 8085 is a -top . . -:1------desk computer .'- . consisting of a combined microcomputer - - 0 oa4lóéró se1o.. CRT terminal and a separate dual floppy - McIntosh ;C 32 rtñ 7 ;) disk storage. The CPU is an 8085A. An

"More Than a Preamplifiér"

can be selected at the touch of a button. Mclntosh.has received peerless ac - Automatic tuning advances the tuner to the next x strong station with equal conve- claim from prominent `product, - !r nience, and manual control allows weaker testing laboratories and .outstand- stations to be chosen. Minimum usable sensitivity (noise and distortion sup- ., ing'.international recognition!' You pressed by 30 dB) is given as 1.6 µV can learn: why the "more ,than. 'a: : (equivalent to 9.3 dBf), with a capture ratio

preamplifier" " C 32 . has been automatic start-up routine, called by a sin- of 1.2 dB. Alternate -channel selectivity is selected for these 'unique 'honors. gle key, locks onto any CRT baud rate from rated at better than 75 dB, image rejection 110 to 9600 and quick -tests each RAM at more than 95 dB, harmonic distortion location; a sign -on message displays (100% modulation) at less than 0.08% in Send ".us your 'name .arid address' installed memory size and indicates that mono and less than 0.1% in stereo. Other and we'll send you the complete the operating system is loading. After features include FM muting and tuning and 'product reviews and data on all about four seconds, the operator has signal -strength indicators. access to any programs on disk. The stan- CIRCLE NO. 96 ON FREE INFORMATION CARD . McIntosh `products, copies '.of.;the..6 dard system includes 32K bytes of RAM internatiónal awards,-and:a North ° (expandable to 56K directly) and 600K American: FM :directory. You "will bytes of on-line disk storage (expandable to 1.2 megabytes). Supplied with Disk Twelve -Inch Video Monitor understand' why McIntosh' product Extended BASIC, a Disk Operating System,

research . and development always debug package, utilities software, and 3K The Leedex Video 100-80 12" black -and - has the áppearance and tech- byte PROM resident system monitor. white monitor for home and commercial $3695. use is plug-in compatible with Apple, Atari, nological° look to the future;,,: CIRCLE NO. 94 ON FREE INFORMATION CARD Radio Shack, O.S.I., Microterm, and Exidy computers. The removable face plate pro - Keep up to date: 3rd Hand Circuit -Board Holder Send.: now, =: -:= Studio 3 has introduced a new version of "the 3rd Hand" circuit board holder. It employs a brass spring, retaining tabs, and McIntosh Laboratory Inc. a PVC gasket to hold a board without Box 96 East Side Station thumbscrews. The 3rd Hand clamps to the Binghamton, NY 13904 edge of the workbench and holds the board at an angle for the placement of Name T components. It can then be flipped over so . Address that solder or wrapped -wire connections e can be made. The 3rd Hand is available in vides mounting space for a mini -floppy disk City State Zip three sizes, each of which can be used and there is also space inside for an 11" by with an optional Extension Bench Clamp 14" pc board. The 90° deflection tube 3rd an If you are in a hurry for your catalog please that holds the Hand 2" (5.1 cm) above allows 80 -character by 24 -line display send the coupon to McIntosh. For non -rush the workbench and 6" (15.3 cm) in from its with a 12 -MHz bandwidth. service send the Reader Service Card to the edge. The Mini Model 3 B/C ($9.95) is 4" CIRCLE NO. 97 ON FREE INFORMATION CARD magazine.

to CIRCLE NO. 42 ON FREE INFORMATION CARD (Continued on page 12)

AmericanRadioHistory.Com a -

,.w.. ufn . LI

' -s

4,1 c

- Z 1"

I . Even at 5:12 am., its hard to quit playing Personal.SoftwaréM strategy games. A quick game before turning in can become an all-night Bridge Partner. You against the computer in over 10 million session when you load any of the Personal Software'" strategy different hands of contract bridge. You can even specify the games into your Apple; PET* or TRS-80* They'll challenge, hands' high card points. Written by George Duisman for -he Ap- teach and entertain you. And now there are two new gamés- ple, PET and Level II TRS-80. $19.95. Gammon Gambler' and Checker King"-joining Bridge Time Trek is easy to learn, dif- Partner,'" Time Trek" and the best-selling Microchess" ficult to ¡aster and impossible to Gammon Gambler is a sure bet. With ten levels of skill, forget. Take command of a starship m9"'''1,140 you can begin a novice and become in real-time action to make the gal- an expert. Whichever level you play, axy safe again. PET version by Brad 11.14 mu._ a the computer moves so quickly Templeton. TRS-80 program ' :« := I. you don't have to wait. The Lv by Jp;hua Lavifsky. $19.95. ,::a=".,:«a. :I ,1'i®1 '«»=':«"« 4i1 11¡ U I program follows U.S. Personal Software, Inc., tournament rules, and in- ,40 also produces the VisiCalc'" that's Checker King VII .di cludes the doubling prcgram (the software ,,... cube to spice up the revolutionizing personal game. Written for computing), CCA Data Management Sys-

I the Apple and tem, the Vitafacts series and other exciting Gammon Gambler PET by Willy software for the Apple, PET and TRS-80. Chaplin. $19.95. Now that you've read about the Per- Checker King-you probably forgot sonal Software programs, go see a how much fun it is! If you move and demonstration. For the name of your change your mind, take it back and move nearest Personal Software dealer, call again-without a peep from the computer. (408) 745-7841 or write to Personal Play eight skill levels. Add and remove Software, Inc., 592 Weddell Drive., 'pieces. Save three board positions for later Sunnyvale, CA 94086. play. And solve three challenging checker u u pu77les. Written by Michael Marks for W I hl the Apple, PET and TRS-80. $19.95. NIA} Microchess, the most widely used 45z 0 personal computer chess program, is a nearly perfect chess opponent for the total novice or the advanced enthusiast. Written 50r by Peter Jennings for the Apple, PET and $19.95. 1gM1-*.4Wj TRS-80. = 'Apple is a trademark of Apple Computer, Inc.; PET is a trademark of Commodore Business Machines, Inc.;TRS-8t) a trademark of the Radio Shack Division of Tandy Corp. CIRCLENO. ON FREE iNOPMAT'C. CARD STRATEGY GAMES SERIES

AmericanRadioHistory.Com NEW PRODUCTS continued

after it has sounded for 10 minutes and Microprocessor -Controlled then resets the system. Perim-A-Tron has Wireless Alarm System an audio output stage that can drive an external PA horn speaker. Basic system oí Universal Security Instruments announces one transmitter and one receiver/supervi- the availability of its Perim-A-Tron micro- sory'module, $149.95. processor -based programmable wireless CIRCLE NO. 98 ON FREE INFORMATION CARD alarm system. Using a built-in keypad, the user can select entry/exit delay times over a range of 5 to 45 seconds and a 3 -digit disarm code and perform system tests. Low -Cost "Superamp" Ultrasonic mounted at transmitters various The Adcom GFA-1 stereo power amplifier, locations in the premises to be protected using two amplifiers per channel in a can be set to operate on either of two lay. The user can employ both delayed and bridged configuration, is rated to deliver alarm channels, as well as to or observe nondelayed transmitters on the same chan- 200 watts per channel to 8 -ohm loads, 20 disregard the programmed entry/exit de- nel. An automatic timer silences the alarm to 20,000 Hz at no more than 0.05% THD and 0.1% IM. Into a 4 -ohm load, the unit is said to be capable of delivering 350 watts.

Rated S/N, A -weighted, at 1 -watt output is 90 dB, with slew rate (80 V/s) high enough universal breadboarding elements to give negligible transient IM distortion. with 840 solderless plug-in tie points. IHF headroom is given as 2.2 dB and input .Combines distribution system with sensitivity for full power output at 1.5 V into .1"x.1" matrix. O Compatible with all DIPS 50 kilohms. The power supply is built and discretes with lead diameters Up tó around a toroidal transformer, and a built-in .032". Needs no special patch cords. fan is provided to assure cool operation at high power. Automatic thermal protection for the output transistors is also incorpo- `91k ,Y+,4 00011 rated. $400. CIRCLE NO. 99 ON FREE INFORMATION CARD Y-1.ti,\ Customized RS -232 -. Interface S- The Remark Model 54 Stunt Box allows the '..: user to create a customized interconnec- 1"-7' . tion between two different RS -232 computer interfaces. The box contains a pc board carrying two DB-25 connectors whose pins are terminated at 0.025" square pins and With alloy 770 terminals,

$17.00. Je.

Your breadboarding is a super-snap with a solderless A P Super -Strip.

Build a circuit almost as fast as as 14 DIPs. many nine -pin plated -through holes. This arrangement alit as you dream up. Pull it Instant -mount backing lows the use of Wire -Wrap or jumper pins apart and do another- and quick -removal screws to interconnect the signal paths. To facili- everything's as good as new. make stacking and racking tate common bussing of particular signals, Our versatile Super -Strip a snap, too. one 3 -point, two 4 -point and one 5 -point mini -breadboards give you Where to buy? Phone (toll - areas are provided. Dimensions are 3.25" the same top-quality con- free) 800-321-9668 for the X 3.25" X 1" (8 X 8 X 2.5 cm). $52. Address: Remark International, 4 tacts you get in our full- name of your local A P dis- Syca- scale ACE All -Circuit Evalua- tributor. And ask for our more Drive, Woodbury, NY 11797. tors. Not so "mini," either. complete A P catalog, The You can build circuits with Faster and Easier Book. Vaco Five -Piece Screwdriver Set

Vaco Products' new Model 70600 is a five - Faster al1dwe Ce a" abealt: piece set of Bull Driver screwdrivérs in a sizes: 3'16", 1/4', and 5/16" slotted; and 3'16" w a A P PRODUCTS and 1/4" Phillips. The drivers have handles INCORPORATED said to be 3546 larger than usual and are 1359 W. Jackson St. fluted with chamfered edges. Tempered, Painesville, Ohio 44077 nickel -chrome Tel. 216/354-2101 plated, chrome vanadium MN: 810-425-2250 steel is machined and ground to form the drivers' shafts and tips. CIRCLE NO. 100 ON FREE INFORMATION CARD

12 CIRCLE NO. 70N FREE INFORMATION CARD POPULAR ELECTRONICS

AmericanRadioHistory.Com Not Just Another Limit'- d Area Motion' Detector!

Protects: Every Square Inch Of Your Buildin

.Turns On. Lights Auto atically

Pówerful Electronic Si ,- I

Low Cost Computerized The Guardex 8000 Alarm System is walnut grained and dis- guised to look like a small stereo speaker (63/."x93/."x8') Burglar Alarm System and weighs less than 61/2 pounds.

Home - Office - Business NO INSTALLATION EXIT AND ENTRY DELAY Just plug the Guardex 8000 alarm system in, make several The Guardex 8000 alarm has a built-in exit delay allowing you simple control adjustments to suit your particular building and approximately one minute to lock up and leave the building it works! There are no other wires to run. This totally self-con- before the alarm is armed. When you enter your building you tained burglar alarm can completely seal off every square inch may find that just your normal entering sounds activate the of the surface of your building. It protects doors, windows, and siren. You may delay it from starting for up to 30 seconds by what most alarms miss...your roof, walls and floors. turning up the siren entry delay control. HOW CAN ONE SMALL COMPUTER PROTECT MY BATTERY BACK-UP WHOLE BUILDING? Burglars rarely cut power. However, to give you total protec- failure, alarm has Guardex 8000 Alarm System works on the principle of audio tion from a burglar and possible power our This, simply, is the process of electronic- provisions for a battery back-up. (Batteries not included). 12 discrimination. put stores. ally separating normal everyday sounds, such as voices, tele- volt lantern batteries are available at most hardware phones, etc. from break-in type noises such as breaking glass, THE BURGLARY PROBLEM prying metal, or forcing a door open. The Guardex 8000 pro- at present rate, one out of tects one story homes and offices up to 2000 square feet and The F.B.I. statistics show that the going to be That is not a open commercial buildings up to 10,000 square feet. The every four Americans are burglarized. it is You have a of Guardex 9300 with wireless remote sensor capability is avail- very pleasant fact, but true. greater chance for multi -story homes and offices or single story with being burglarized than being a victim of a fire or automobile able is help and more than 2000 square feet. Call the factory for more detailed accident. The time now to protect yourself your information. valuables with a Guardex 8000 alarm system. TURNS ON LIGHTS AUTOMATICALLY OUTSIDE SIREN a loud, siren, When the first break-in type sound is detected, the system will The Guardex 8000 alarm is equipped with built-in you mount or in an instantly turn on lights, radio, or other electronic equipment but if desire an additional siren to outside from the main alarm, they are available with 50 feet that you have plugged into the back of the alarm. These lights area away wire for (Connecting terminals are provided on the or other equipment will remain on for a period of five minutes, of $24.95. then automatically turn off. back of the alarm). POWERFUL ELECTRONIC SIREN 30 DAY NO RISK TRIAL an system The Guardex 8000 alarm is equipped with a loud built-in siren. This is your opportunity to purchase alarm directly five minute period the lights or other electronic from the factory for only $199.95. Try it in your home or busi- If during the Put our Guardex equipment has been activated, a second break-in sound is de- ness for thirty days without risking one cent. 8000 alarm to your own test. See for yourself! It will protect tected, (it can be only a second or two after the first break-in If you are not sound) the built-in siren will start blasting for 90 seconds. At the every window and door from break-in. completely for a refund. end of approximately 90 seconds the siren will shut off and the satisfied, return the alarm within 30 days complete sound is heard, the To order your Guardex 8000 alarm, CALL TOLL FREE to charge alarm listens again. If another break-in Electronics, siren will come on for another 90 seconds. If no other break-in your credit card or send your check to Guardian $199.95. If you the optional outside sound is detected, the siren will stay off and at the end of the Inc. in the amount of want five minute period the lights will shut off and the alarm in- siren, add $24.94. (California residents add 6% sales tax.) stantly resets. require more information. (If you r --- call during California business

hours, Monday - Friday) Dealer Inquiries Invited The rear control panel ® CALL TOLL FREE California residents: contains two standard AC (800) 423.5499 (213) 889-1414 collect. plug receptacles for a table lamp, spot lights, radio, etc.; terminals for connecting GUARDIAN optional outside siren and back-up battery (not ELECTRONICS, INC. included); entry delay time control and sensitity control. 31133 Via Colinas, Dept. PE. Westlake Village, Calif. 91361

POPULAR ELECTRONICS CIRCLE NO. 28 ON FREE INFORMATION CARD 13

AmericanRadioHistory.Com enced engineers in technologies such as fiber terized security using microwave, ultrasonic, optics, digital ICs, complex MOS memories, card -access, and closed-circuit TV tech- bubble memories, and codecs at GTE Auto- niques. Ask for Form 948-00 from: ADT, One matic Electric Laboratories. Address: J. World Trade Center, 92nd Floor, New York, Douglas Allen, GTE Automatic Electric Laoo- NY 10048. ratories Inc., 400 N. Wolf Rd., Northlake, IL 60164. BECKMAN PORTABLE MULTIMETERS

SECURITY SYSTEMS BOOKLET The new TECH 300 and TECH 310 3'h - New Literature Security systems for commercial, industrial, digit portable multimeters are described in a institutional and residential applications are bulletin from Beckman Instruments. Features described and illustrated in "ADT High Tech- on the new instruments include 2000 -hour typ- nology Security for People, Premises and ical battery life, a semiconductor test function EMPLOYMENT OPPORTUNITIES BROCHURE Profits." Basic operations and benefits are and overload protection on all ranges. The "Career Opportunities in Telecommunica- outlined for automated central stations, direct TECH 300 ($110) features 0.5% of reading tions" describes jobs available for experi- police and fire response, and on -site compu- accuracy of five dc voltage ranges, with five ac voltage ranges, and ac and dc current measurements on five ranges. The TECH 310 ($140) is similar with 0.25% accuracy and an electrical continuity checking feature. Ad- dress: Advanced Electro-Prodúcts Div., Beck- Sabtronics Model 2035A man Instruments, Inc., 2500 Harbor Blvd., Ful- lerton, CA 92634. Handheld DMM Kit e

No other hand-held DMM CI; PORTABLE SCOPE BULLETIN Gould's new OS1200 portable, 25 -MHz, dual - offers you so much performance trace oscilloscope is described in Bulletin for such low cost. 449-12. The OS1200 features of 5 -inch rectangular CRT operating with 6 -kV accelerat- ing potential. It has a 14-ns rise time and 0.1% Basic DCV Accuracy signal delay facility for digital work with nar- Easy one -hand operation row pulses and low repetition rates. Address: Gould Inc., Instruments Div., 3631 Perkins 6 Functions - 32 Ranges Ave., Cleveland, OH 44114. Touch -and -hold capability ` ,.p. Two -terminal input for lább&OryrC 4 SCANNER FREQUENCY DIRECTORY ALL measurement functions --"'«k1711417,4 Electra has introduced a new "Betty Bearcat Hi -and -Low Power Ohms Frequency Directory" which groups frequen- Easy -to -build, one evening cy listings of police, fire, ambulance, public utilities, railroads, and other services by lis- assembly Model 2035A tening areas. In this way, the directory is 'with optional THP-20 Probe. $74.95 intended to eliminate hunting through state- r.o.a. r.,r,nry wide alphabetical listings. The directory also Plus these standard features: has a section with a fold -out FCC frequency allocation chart, 10 -code data, antenna tips, Large, easy -to -read LCD readout; automatic and other reference information. A cross-ref- polarity; automatic zero; BRIEF automatic decimal point; SPECIFICATIONS: erence section listing users by frequency is low DC VOLTS: 100, V - 1000V, 5 ranges battery indicator; overload protection on all included to help identify signals. The directory AC VOLTS: 100, V - 1000V, 5 functions and ranges, and 200 ranges hour operation DC CURRENT: 0.1p A - 2A, 5 ranges ($12.95) is published in editions for the East- from a 9V transistor battery. AC CURRENT: 0.1, A - 2A 5 ranges ern and the Western U.S.A. Available from

Hi -OHMS: 0.1 9 - . 20M It 6 ranges Bearcat scanner suppliers or Electra Co., Lo -OHMS: 0.19 - 20M ti , 6 ranges P.O. Box 29243, Cumberland, IN 46229. Size: 3'/: "Wx6'/. "Lx 1 5/8"H r ... . Sabi S WEIGHT: 11 oz. (excl. battery) iNTERNAT.ONAL "IC OVERLOAD PROTECTION: 1000V DC SPARKOMATIC SOUND CATALOG 5709 North 50th or AC peak all voltage ranges, 250V Street, Tampa, Florida 33610 DC or AC peak all Ohms ranges; A new 44 -page catalog describes Sparko- Telephone 813/623-2631 2A/250V fuse all current ranges. matic's line of car stereos, speakers, graphic equalizers and amplifiers and power boost- r i ers. Included is the 100 -watt high-fidelity SPX To: Sabtronics International, series, which includes the GE 1000 graphic Inc., 5709 N. 50th Street, Tampa, FL 33610 equalizer and amplifier rated at 100 watts and Please send me the SK 6950 and SK 650 4 -way 100 -watt stereo speaker sets. Address: Sparkomatic Model 2035A Handheld Multimeter kit(s) ® $74.95 ea $ Corp., Milford, PA 18337. Shipping and handling ® $5.00 per kit (see below)t $ Model THP-20 Touch -and-hold Probe(s) @ $19.95 ea Model AC -110 Battery Eliminator(s) $7.95 ea. ® $ ANTIQUE RADIO SERVICING PUBLICATIONS Model HVP-30 30 kV DC High -voltage Probe(s) ® $29.95 ea $ Antique Radio Services sells individually or in Florida residents add 4% Stale Sales Tax $ sets servicing materials for many early mod- TOTAL $ els of radios and TV receivers. These include I enclose U check' U money order. Bill my U Master Charge U Visa Rider's manuals, Sams' "Photofacts," and Card Account M Expir. date 'Allow 2-3 weeks clearance time for personal checks. No C.O.D. early Supreme Publications, among others. A complete list of materials and sets available Name is obtainable. Address: Antique Radio Ser- Street Apt. vices, 646 Kenilworth Terrace, Kenilworth, IL. 60043. City Stale Zip yContinental U S. only. AK. Hl & PR. $6.00. Canada' $7 50 Foreign: $19.00 Airmail. L J POPULAR ELECTRONICS

AmericanRadioHistory.Com INCREDIBLE CASSETTÉ OFFER! a$ LCD digital

Try 10 DAK high energy cassettes risk free for only $2.19 each and get a beautiful $69 value LCD digital watch for only $5.

It's your choice. Think about the kind ±3db Virtually all cassette recorders comfort. No cheap imitation, a first rate of music you like. You don't want to priced under S600 are flat ±3db from locking adjustable band. think about cassettes jamming, loss of 40cps to about 12,500cps, so we have It's guaranteed. This fine watch comes high frequency response or tape hiss. over 2000cps to spare, and you'll with a manufacturer's limited warranty DAK manufactures a cassette that you probably never notice the difference. for one full year. can really forget about. Great sound, No apology. We feel that we have and no problems. And, for only $5 we equaled or exceeded the mechanical hope you will think a lot about your reliability of virtually all cassettes and new LCD digital quartz watch. offer one of the best frequency respon- YOUR TIME IS PRECIOUS ses in the industry. Maxell UDXL is a rugged Imagine yourself just finishing record- truly the Rolls Royce of the industry, micro -computer ing the second side of a 90 minute cas- and DAK is comparable to the 100% US sette and horrors, the cassette jams. made Cadillac or Corvette! Tape is wound around the capstan, your Price DAK manufactures the tape we recorder may be damaged and you've sell. You avoid paying the wholesaler just wasted 90 minutes of your time and and retailer profits. While Maxell UDXL DAK TAKES A RISK perhaps lost a great recording off FM. 90s may sell) for S3.50 to $4.50 each at Obviously giving away quality watches Enter DAK. We manufacture over one retail, DAK ML9Os sell factory direct to is not going to make DAK rich. Even million units of cassette tape each you for only $2.19 each complete with giving away cheap watches wouldn't month in our North Hollywood factory. deluxe boxes and index insert cards. help. We are betting that you will buy Many of our tapes are used for high ._ our cassettes again, and we are putting speed duplication where they are our money where our mouth is! recorded at speeds up to 8 times nor- Customers like you are very valuable mal. This is the ultimate stress for in the form of future business. We cassettes and causes more failures than anticipate receiving over 6000 orders any other use. and 4500 repeat customers from this MOLYSULFIDE advertisement to add to our list of over We developed polyester slip sheets 57,000 actives. with raised spring loaded ridges to guide TRY DAK ML90 CASSETTES FREE each layer of tape as it winds. We coat Try these high energy cassettes on them with a unique formulation of Gra- your own recorder without obligation phite and a new chemical, molysulfide. for 30 days. If you aren't 100% satisfied Molysulfide . reduces friction several for any reason, simply return the tapes times better than graphite and allows and the watch to DAK for a full refund. the tape to move more freely within the To order your 10 DAK ML 90 minute cassette. The molysulfide is tougher and high energy cassettes at $2.19 each and makes the liner more resistant to wear. the $69 value watch with your credit were hot on our free number Evidently 3M and TDK A $5 LCD WATCH? card, simply call the toll heels, because they have now also come below, or send your check for $21.90 Of course not! This is an incredible liners. plus for the watch and $3 for pos- out with new offer. Countless stores throughout the $5 Hi frequency protection! Tape is basi- tage and handling for each group of 10 country sell LCD quartz crystal watches as moves within the and each watch to DAK. cally plastic, and it like this for up to S69. cassettes sales tax ) cassette friction causes the build up of This beautifully styled slim silvertone (Calif. residents add 6% electricity, much as rubbing a bal- DAK unconditionally guarantees all static watch is loaded with features. LCD hair, or scuffing DAK cassettes for one year against any loon against your means that the time in hours and a defects in material or workmanship. your shoes on carpet in dry weather. minutes always shows without having to the cassette is Why not order an extra group of 10 Static electricity within push buttons. Push the button once, reduced by the low friction DAK ML90 cassettes for yourself or a drastically and you'll see the date in months and its friend? We will add one free ML90 cas- of the molysulfide so that tendency days, and push the button again and the sette to each 10 you buy and of course to erase very high frequencies is drasti- watch shows seconds. you can buy one $69 value watch for $5 cally reduced. A very important consid- Night light. Usually only found in the eration for often played tapes. with each group you buy. most expensive watches. Simply push a © DAK Industries, Inc., 1979 MAXELL IS BETTER button and the entire time section lights Yes, honestly, if you own a $1000 cas- up for convenient night viewing. DAK deck like a Nakamichi, the fre- Quartz crystal accuracy means con- sette INDUSTRIES quency responses of Maxell UDXL or stant time within 1 minute per month. TDK SA are superior and you just Crystals use little electricity, so the bat- INCORPORATED might be able to hear the difference. tery should last up to a year, and Call TOLL -FREE (800) 423-2636 DAK ML has a frequency response may be easily changed by any jewler. n California Call (213) 984-1559 that is flat from 40cps to 14,500cps Stainless steel band for long life and 10845 Vanowen St., North Hollywood, CA 91605 MAY 1980 CIRCLE NO.16 ON FREE INFORMATION CARD 15

AmericanRadioHistory.Com Ever: body's making money. se' ink miçrócomputers. Somebody s doing to make money servicing Them. New NRI Home Study Course Shows You How to Make Money Servicing, Repairing, and Programming Personal and Small Business Computers

16 POPULAR ELECTRONICS

AmericanRadioHistory.Com Seems like every time you turn around, Assemble Your Own Other Opportunities somebody comes along with a new Microcomputer in Electronics computer for home or business use. NRI training goes far beyond Since 1914, before commercial radio And what's made it all possible is the theory. It includes practical experience, too. was even on the air, NRI has been the way amazing microprocessor, the tiny little As you progress, you perform meaningful to learn new electronics skills. 'Ibday's chip that's a computer in itself. experiments building and studying elec- modem offerings include, in addition to Using this new technology, the tronic circuits on the NRI Discovery Lab® three different computer courses, TV/Au- industry is offering compact, affordable You assemble test instruments that in- dio/Video Systems Servicing, with training computers that will handle things like clude a transistorized volt -ohm meter and on the only designed -for-learning 25" payrolls, billing, inventory, and other a CMOS digital frequency counter... instru-- diagonal color TV, with state-of-the-art jobs for businesses of every size...per- ments you learn on, use later in your work. computer programming. Or, check out form household functions including our Complete Communications Course, budgeting, environmental systems preparing you to enter this booming control, indexing recipes, and more. field servicing, installing, and repairing And thousands of hobbyists are already equipment like microwave, broadcast, CB, owners, experimenting and developing shortwave radio, paging, radar, and more. their own programs. Mail Postage -Paid Card Demand Growing for for Free Catalog Computer Technicians No Salesman Will Call This is only one of the growth . S Send today for your free copy of our factors influencing the increasing .-*' ,or. 100 -page, full -color catalog. It describes all opportunities for qualified computer , of our electronics courses in detail, show- technicians. The U.S. Department of ing kits, equipment, and lesson plans. Labor projects over a 100% increase in Look it over at your convenience, then job openings for the decade through decide how NRI can help you make the 1985. Most of them new jobs created by And you build your own microcomputer. most of your talents. There's no obligation the expanding world of the computer. Each step of construction advances your and no salesman will ever call or bother knowledge, gives you deeper insights you. With more than a million students Learn at Home into this amazing world that's upon us. and unmatched experience in home train- in Your Spare Time This is the only microcomputer de- ing, NRI gives you the most in training you signed for learning. It looks, operates, and NRI can train for new opportunity! If card has been E, for this exciting, rewarding performs just like the finest of its kind...ac- ~ removed, write to: field. 'Train you at home tually does more than many commercial to service not only micro- units. But NRI engineers have designed NRI Schools computers, but their larger components and planned the assembly McGraw-Hill Continuing NRI Education Center brothers, too. Train you at procedure so it demonstrates important 3939 Wisconsin Avenue your convenience, with principles, gives you working experience I Washington, D.C. 20016 problems.. clearly written "bite -size" in detecting and correcting 1E111Y lessons that you do evenings And that's

1 or weekends, without what NRI . going to classes training or quitting your is all 511 present job. about.

(o.

111

de,

MAY 1980 19

AmericanRadioHistory.Com Feedback Cause:

T." ,

"......

Feedback Cure: DISCWASHER°

is 00 TM Hi -Technology Turntable Isolation System Works in combination with existing feet for dramatic reduction of feedback. Isolates better than original or "replacement" feet.

Home environments can "upset" a The DiscFoot System contains four turntable by feeding back both isolation feet, four platform caps,. four speaker and footfall vibrations. furniture -protecting sheets and four Acoustic isolation of a turntable special damping pads (to adapt involves the complex variables of WITHOUT DISCFOOT DiscFoot units to certain turntables.) turntable weight, room/floor Additional single DiscFoot units are conditions and audio system place- available for turntables weighing over ment. The Discwasher DiscFoot has 22 lbs. The system costs $22. been specifically designed to success- fully isolate most turntables in the WITH DISCFOOT home environment. The "Material" Solution The Telling Test W.DiscFoot. The major components of the The oscilloscope photo shows the Discwasher DiscFoot System are output of two identical audio systems Discwasher DiscFoot can be found at new, "totally engineered" chemical on the same shelf with their styli audio dealers interested in preserving complexes that behave radically contacting the platters. The shelf is your music. different than other plastic, rubber or being struck by a rubber mallet. The spring systems. These proprietary top trace shows a turntable with compounds are durable and precise absorptive "replacement" feet. The in behavior; although difficult and lower trace shows a DiscFoot System discwasher, inc. expensive to synthesize. Laboratory operating in conjunction with the 1407 N. Providence Rd. and real -world tests justify the use of existing turntable feet. Note, the tiColumbia, Missouri 65201 these unusual materials in the dramatic (tenfold) improvement in DiscFoot System. shock and feedback isolation. 20 CIRCLE NO. 19 ON FREE INFORMATION CARD MAY 1980

AmericanRadioHistory.Com Myth: Audio Equipment is Ugly. First, let's establish that audio equipment is not without visual appeal. Actually, it would be surprising indeed to find that the large amounts of money that manufacturers invest in cosmetics do not produce at least some positive effects. The problem is that the equipment is seldom shown, in advertisements or store displays, in conjunction with Stereo Scene other furniture. Thus we have little information as to how the designer envisioned them positioned in the home. Interior decorators have contributed to the difficulty as well. How often By Harold A. Rodgers does one see a model room-or its photo- Executive Editor graphic rendition-into which an audio system has been integrated? Such a state of affairs places great demands on the imagination of anyone who wants an audio system to make constructive DOMESTIC HARMONY counterpoint with the rest of his environment. For example, it is often said that loudspeaker systems are boxes and no matter what is done to them they stand their ground in pris- ONE OF THE oldest "truisms" that infect surroundings and likely to be dominated by tine, unmollified boxiness. But to take this audio retail circles has it that the man of the unreasonable demands of their spouses. point of view is to blind oneself to distinc- the house chooses equipment on the basis of Women, on the other hand, are seen as sin- tions, subtle though they may seem at first, its performance and the "little lady" exer- gle-minded, irrational, and totally devoid of that may allow one model to fit in where cises her traditional veto power on the basis concern about the place of music in the another might clash intensely. Tables, after of cosmetic appeal. Further, in this scenario, household. all, don't really look all that different from the female half of the partnership, through If audio equipment is to be introduced into each other either; it is simply that through some unstated form of terrorism, dictates the a home setting, both its acoustic and visual experience and training most of us are capa- placement of the equipment exclusively effects will have to be given their due or the ble of appreciating many of the differences. according to principles of interior decorating, job will not be done sensibly. In fact, one regardless of whether or not they make any would expect an aware salesperson to note The Role of Audio Furniture. Equipment acoustic or electronic sense. this from the outset and proceed accordingly, racks and loudspeaker stands are aids to Enlightened thinking, one would hope, will especially if his prospective customers are a harmonizing equipment with its surroundings. recognize this view as sexist and slanderous couple. To behave otherwise could easily In addition to the beneficial acoustic effects to all concerned. On one hand it depicts men leave one partner or the other with a reason often contributed by the latter, they can as insensitive to the visual aspects of their not to buy. usually put what might be dismissed as "just another box" in a visually more advanta- geous perspective. Stands that tip the loudspeaker a few degrees backward from vertical can (provided the speaker's acoustic design permits) do particularly well with respect to both of these criteria. Racks have been offered by stereo component manufacturers for some time now, though often as an inducement to buy equipment all of the same make rather than "mix- ing and matching" as many people do. Most often, therefore, racks are displayed with equipment of the chosen brand installed and are designed, if possible, to make that equipment look better than its competitors. This should not dissuade the prospective pur- chaser from asking that alternative units be positioned in the rack, if they will physically fit (they won't always). In addition, there are rack suppliers, such as Gusdorf and Reco- ton, whose products are designed to accept any equipment with reasonable grace. Making the Right Decisions. Generally, it will be easier to blend a music system into your home in an optimum way if you are redecorating at the same time. Then everything-audio equipment, furniture, carpeting, draperies, etc.-can be chosen to work together. There are a few principles to bear in mind while making one's choices: 1. Try to position any equipment that has controls (preamp, tuner,. tape deck, etc.) where they can be reached from the listening ak position. Few things are as frustrating as getting up to adjust a tone control, going w back to the listening position to check the sound, finding that it is not quite what you -r,f. want, and having to repeat the entire procedure several times.

MAY 1980 21

AmericanRadioHistory.Com 2. Give up outmoded ideas about positioning sure that they run under a couch or within an plan that nothing on earth will move you, for loudspeakers in odd corners or places where inch or two of a baseboard, where no one there are many good reasons for making revi- they be To can hidden. do this will hide their walks. (Electric power lines should not, how- sions. One possibility is that a salesperson sound as well-or make you wish that you ever, be covered by carpets.) may be able to offer you a substantially bet- could hide it. Plan on speakers having a posi- 6. Don't be afraid to experiment with unusual ter price on a component other than one you tive role in the decor, and position where they furniture configurations. For example, sofas had preselected. By all means, consider will give good sound. (Some acoustically are usually placed so that the long dimension attractive deals when they are available, but based hints on speaker position were given parallels one of the walls of the room. Placing remember why you chose the model you did in the September 1979 installment of this one a few degrees out of such parallelism in the first place, what you expected it to do, column.) If you absolutely must conceal may add an individual touch to the room and and how you will fit it into your environment. If speakers, the consider use of acoustically make the formation of standing waves less - it all checks out, go for the deal. That way transparent curtains that will fit with other likely or prominent. good listening can fit harmoniously into your room accessories. 7. Be realistic in your choice of equipment. home and lifestyle. 3. Plan on using some sound -absorbent Trying to make a pair of large, electrostatic material in the room. This can be in the form panel speakers fit and function well in a small of stuffed furniture, carpeting, draperies, etc. apartment can be an exercise in futility. On These need not be applied over whole sur- the other hand, don't let the unobtrusiveness faces. In fact, some studies have shown that of minispeakers tempt you into putting them quasi -random application of damping materi- in a situation where they will be over their al gives more efficient results. in general, heads trying to fill a large room with sound. surfaces near either the speakers or the lis- You may get by, but overdriven speakers and tening position are the ones from which the distortion are more likely results. most troublesome reflections arise. If you are trying to fit an audio system into 4. Position the turntable as far away from the an existing decor, the problem is harder. speakers as is practical; this will tend to Most often, if you are serious about hearing avoid acoustic feedback. On the other hand, music reproduced with high fidelity, you will Audiophile Recordings you may want it near the listening position for have to make changes. (Light under a bushel maximum convenience. To the extent that basket or speaker behind an overstuffed these desiderata conflict (some preferred lis- chair, it's all the same.) But if you do your DIGITAL RECORDING VOL. 111: BIZET, CARMEN PRE- tening positions are quite close to the speak- advance planning and have some idea of how LUDE; BERLIOZ, RAKOCZI MARCH FROM DAMNATION OF ers), trial -and -error may be the best guide. you will integrate the system into the design, FAUST; BRAHMS, HUNGARIAN DANCE No. 5; GINAS- But don't put the turntable so close that you you can usually work out some solution. TERA, PANAMBI SUITE; RIMSKY-KORSAKOV, PROCES- will continually bump it. If all of this suggests to you that purchas- SION OF THE NOBLES FROM MLADA. Zoltan Rozs- 5. Do not run wires where they will be trod ing an audio system is not something to be nyai conducting the Philharmonica Hun- upon. This can easily cause disasters. If you done on impulse, you are beginning to get the garica. M & K Realtime Records (dbx encoded) PS-1002. Well, dbx has done it at must conceal wires under a carpet, make point. I don't suggest that you make so rigid a last. This and several other records released at the same time by M & K are the first dbx-encoded, digitally níastered discs-and this one, at least, is a sonic standout. The EXPAND YOUR sound is so clean (the background hiss that the dbx compander pumps up and down on normal recordings is now, for practical pur- REGARD COLLECTION poses, out of the picture) that it actually takes a bit of getting used to at first. I was able to hear a playback of the master tape of WITHOUT BUYING MORE the Ginastera-probably the most interesting

work on the disc-and as far as I can tell its REGARDS. quality is transferred virtually intact to the disc. Rozsnyai and the Philharmonica Hun- With the Pioneer RG-2 Dynamic Processor, you'll hear everything garica do an especially fine job with this early on your records that the artists put into them. Like the extreme loud and work 'of the Argentinian composer, capturing soft passages that are lost during the recording process. The RG-2 can the drive and incisiveness of the Music-in help restore your music to its original condition. It not only expands the second movement, for example-while dynamic range up to 16dB, but it also reduces tape hiss and other noise losing none of the tender, subtle moments. by as much as 6dB. And you'll be glad to know our range expander is in The more limited scope of the other works keeps them from being as inspiring, but a most reasonable price range. So you can use the money you save to they' are well played and recorded. expand your record collection even further. outstandingly

VIVALDI: THE FOUR SEASONS. Gunars Larsens, solo violin; Rudolf Baumgartner conducting the Festival Strings Lucerne. Denon PCM Recording OX -7174 -ND. This is a very well made and recorded disc that really lets the inner voices (second violins, violas, and harp- q sichord) project and demonstrates that Vival- M di is not just melody and bass. The one tech- O nical shortcoming I noticed is that the solo violin is placed so far to the left that its sound ºe r+uvema .. o ..... often gets mixed up with the massed solo violins. As the liner notes candidly admit, the interpretation is not an exercise in Baroque purism. This is not an unreasonable approach SYSTEM ENHANCERS when modern instruments are used, and the ©1979 U.S. Pioneer Electronics Corp. 85 Oxford Drive, Moonachie; N.I. 07074 result is certainly enjoyable. Soloist and orchestra play with spirit and brilliance that ID PIONEER® under We bring it back alive. Baumgartner keeps sufficient control to prevent the effect from being heavy- CIRCLE NO. 59 ON FREE INFORMATION CARD handed or overdone.

22 POPULAR ELECTRONICS

AmericanRadioHistory.Com Now you can create country fresh air in Ionospherés electronics are both superb Why do we need ionizers at all? your home or office. And also watch and unique. It is the only ionizer that uqes "pas- Urban life has upset the natural electrical cigarette smoke, pollen, dust, and other sive multi -stage" circuitry for its noiseless and balance of the air. Modern conveniences like airborne particles disappear from your env.- noninterfering output (many units are known heating, air conditioning, telephones and ronment, for less than three cents a week. to affect radio reception). Most other units use televisions greatly deplete negative ion All it takes is a small 21/2 pound pollution a "vibration" mechanism, which causes clicks, levels, robbing the air of its natural cleansers. fighter named Ionosphere. Which, we're pops or an annoying high-pitched whine. This is also why we feel uncomfortable under convinced, is the most The circuitry is fluorescent lights. superbly engineered embedded'in epoxy Ionsphere restores this balance in just under $200 air ionizer resin, then encapsu- minutes. The air smells good again, even on the market today. lated in an impact- after smoking. Bar none. resistant sphere-a And, as a result of its work, you may The Sharper solid seamless ball of need to clean your walls in a year or so. But Image is offering Iono- fine ceramic tile. be glad that same soot was kept out of sphere through the Hermetically sealed, your lungs. mail for just $89. it is protected from Try one, or order a system. Ionosphere the moisture that The $89 Ionosphere comes in white purifies the air you inevitably reduces (#946) or black ceramic (#945). Or you may breathe more efficient- the performance of expand your fresh air environment at an $18 Power use: approximately 3 watts. Total Ion output: ly than any fan, 3.8 x 10" ions/sec. Ion density: 10,000 Ionslcublc competitive units. savings-with three units at $249; 2 white, exhaust unit or con- centimeter at 8'. Ozone production: less than .03 ppm. We know of no other one black, (#947). Either way, you can ventional filter system N,O production: not measurable. company that takes experience the freshest air you've probably by creating a negative electrical field. One such pains in producing their product. ever breathed, without obligation. Iono- 4 -inch unit will ionize up to 250 square feet, . Other significant differences? For one, a sphere comes with full instructions and or an average 12' X 20' room. This vastly superior ion emitter than you'll find a one year warranty. And if you're not negative charge acts on floating particles- elsewhere. This easily removable element is delighted, simply return your order even invisible ones-causing them to cluste:, made from surgical stainless steel bristle, not within two weeks for a prompt and fall to the floor or adhere to nearby surfaces. the more commonly used copper "fuzz" or courteous refund. The air becomes pure, feels almost "washed" nickel -plated points. (These have short life And Ionosphere is so efficient it requires no spans, do not clean easily, and in short time fan or other moving parts to disperse lower their output.) The Ionospherés emitter ORDER NOW TOLL FREE. these ions. will last a lifetime, and cleans easily under WES MIMI 1111111Z all Ell IN WIZ EMIR You probably have experienced this hot water. wl Credit card holders may call the toll - fresh -air feeling before. In nature, negative On other units, you'll also find inexpen- free ordering number, seven days a ions are continually recreated by the sive plastic cases. When exposed to a high El week, anytime. Please have the product dynamic action of the sun, rain and lightning. voltage field, these petrochemicals can be number ready. Or send your check, add- Its why air smells sweet and invigorating converted to a harmful gas. But Ionospherés ing sales tax in CA (5.34 for one, 14.94 after a thunderstorm, or deep in a forest. tile case is completely safe. for three). Plus $3.50 delivery. Please order now to insure early delivery. Born in academia. More ions aren't necessarily better. ® Major ion research has been conducted One 4" Ionosphere generates approxi- at the University of California, Berkeley. Ion mately 3.8 trillion ions every second. Unlike E 800 227-3436 In California 622-0733 Systems, Inc.. a private company, was other units which produce an excessively ® 800 founded to manufacture ionizers to the high output (at the source only), the rigorous standards of this research commu- Ionosphere creates a more naturally bal- THE SHARPER IMAGE nity. Headed by senior engineer D.A. anced ion environment. You should also 260 California Street, Dept IS- 049 Gehlke (formerly with the government's avoid units without stated levels of ozone San Francisco, CA 94111 Polaris Project), I.S.I. has built almost every production (Ionosphere is among the lowest). (415) 788-8880 hospital ion system in the U.S. Their new portable Ionosphere is constructed with this same level of integrity. IR IONIZIER WIT THE SCIENUFffC NE.

. 01989 The Sharper L r

MAY 1980 23

AmericanRadioHistory.Com Listéñ -with ári 801= . Omñisóñic lmágerr;M o; -afquañtum leapfórward iri.:stereó_repródüctiorr! ,

-OMNISONIC IMAGERY" IS HERE! . á_, THREE DIMENSIONS IN SOUND! Our innovative state-of-the-art electronics create Stereo withoutan 801 Omnisonic lmáger produces a totally unique sound environment never before sound from two distinct sources. Music from the possible. With an 801 O.mnisoniclmager", you can speakers arrives at your ear, but most of it falls to ° , now experience the physiological sensation of what the floor. The result is often "muddiness" and loss amounts to three-dimensional sound reproduction` - of presence. Only two dimensions result - volume 14 - what we call omnisonic imagery" - from just level and stereo separation: two speakers! Sound appears to come from many sources in the listening area, depending on the Stereo with an 801 Omnisonic Imager" creates quality of the signal source. A common reaction omnisonic imagery" never before possible. Sound is to look about for other speakers. And you don't seems to come from the near and far. At times, it have to sit rigidly fixed at a focal point between surrounds you,and appears to come from behind ° the speakers to enjoy omnisonic imagery'"! you and below you. The sound never has a chance to fall to the floor. It is so alive with movement RETROFITS TO MOST STEREO SYSTEMS! that it envelopes you. Three dimensions - volume Any unit with a tape monitor facility (internal tape level, stereo separation, and omnisonic imagery" loop) can mate with an 801 Omnisonic Imager" It are apparent with an 801 Omnisonic Imager. also has a built-in tape monitor button so you don't lose your existing tape monitor facility. LIFETIME WARRANTY!' You get a lifetime warranty on the active 'circuity, The 801 Omnisonic Imager" works on any stereo ° and one year on all other components (excluding source- FM, tapes, and records.. You can record case and line cord), provided. your 801 Omnisonic selections via the 801 Omnisonic Imager" and replay Imager is used asspecified, ° them on conventional home -use stereo equipment.

Now that you've read all about our 801 Omnisonic Imager, don't you think it's time to hear one? If we have. stimulated your interest in seeking the finest sound reproduction in the purest sense, please ask your dealer fora live demonstration. If you have any questions, or need owMis"etc Woo 3 0 r _ _ to know the name of the dealer ~AQE11 t o nearest you, call or write to: MNISONiX,LTD. P.O. Box 307 Wallingford CT U.S.A. 06492 (203) 237-4203/265-9753

Dealers - join our rapidly -growing' network. Write to our Sales Dept.. for details. Visit our booth at the June C.E.S., Chicago. D-26 Lobby Level, Honeybox", Omnisonic Imager", Omnisonic Imagery',. and HBX" are trademarks ' of Omnisonix, Ltd. . . CIRCLE NO.51 ON FREE INFORMATION CARD

AmericanRadioHistory.Com LL a C_ MUSICAL CHRONOGRAPH A. MI) -IN! This new Salton Drink Mixer plays "Oh, Susannah" when you It's a a - gives you tl-e latitude of a bartender set the alarm. watch, ship or soda fountain specialist. It means watch a calendar and an alarm. the hour if A ' business with a high speed commercial Chimes every hour on quality motor. Very simple and safe: you wish. Showslime, date and features a 6 digit stopwatch Opera_es on AC. #51549 $19.95 (2.65)t -, function. By Marcel. LCD display, B. SH=EPS{IN THROW for your - dial light. car teat. Choose beige or dark Salon ' #51568 S79.95 (2.40)t brown plush_ Each measures`approxi- PUMP.Cóuld mabely 27" x 40:' has straps and D COMPRESSOR have a loops- o keep it from slipping. be quite a lifesaver if you low it could be a 'Beige#51561 $49.95 (3.50) tire, or breath-. ' 'sever for inflatable boats, toys, Bfown Plush #51557 $49:95(3.50). - pools, etc. All packed inside a m3lded plastic carrying case. Features include a pressure gauge far accurate air filling. Just plug

- ittinto your car lighter! i` *45094 $49.95 (3.05)t E_ SAFETY COMBINATION:, snoke and burglar alarm in one -

. portable unit: Just hang the unit - - ' over the door, and activate the' on/off 'switch. Separate alarms distinguish smoke from intrusion: la41ffil 85 l Low,batte?y signal, loud decibel

horn. 4" k 3',x 6:' By Wells Fargo. ¡ - #45092`$39.95 (1.95)t

F. CAR VACUUM plugs into the - llI

cigarette lighter of your car. From p ,

that point,you'IF be'able to reach PPPPPP

_ front back s'eats and floors! I A and The unit is 17V2" long and the set ireludes 3 attachments. -#51555 $21.95 (3.30)t

hr'

.F. 1

,'t

phone! PRODUCT GALLERY Call Tell Free 800-Order SEND ORDERS TO: Giltmaster Dept. ZE 50 Print Name P.O. Box 1692 3825 W. Green Tree Rd. Address Apt. # Milwaukee, WI 53201 rws City ._ Allow 3-4 weeks for delivery. State Zip SHIPPING ITEM NO. OTT. UNIT COST 3 HANDLING TOTAL

CHECK METHOD OF PA(MENT Check or Money Order Sub Total S

1 Diners Club C Master Charge Add appropriate S American Express C Visa state sales tax.

Make check payable to Giltmaster, Inc. TOTAL S Credit card orders withput your signature and exr iralion date cannot be processed. Exp. Date 1 Credit Card No No ( { .7) Price in parenthesis Telephone Z E 50 indicates shipping charge. Signature Please add to unit cost of,ilem;

tWarranty available

Y AmericanRadioHistory.Com When you do,you'll probably pick CIE. You can't afford to settle for less when it comes to something like electronics training that could affect your whole life.

26 MAY 1980

AmericanRadioHistory.Com All this training takes effort. When you shop around for you learn and review the basics- But enjoy it. And it's a real tires, you look for a bargain. perform dozens of experiments. you'll plus for a troubleshooting career! After all, if it's the same brand, Plus, you use a 3 -in -1 precision better price-why not save money? Multimeter to learn testing, checking, analyzing! Do you prepare for Education's different. There's FCC License? no such thing as "same brand'.' No your two schools are alike. And, once Avoid regrets later. Check this you've made your choice, the out before you enroll in any training you get stays with/you for program. the rest of your life. For some troubleshooting So, shop around for your jobs, you must have your FCC training. Not for the bargain. License. For others, employers For the best. Thorough, profes- often consider it a mark in your sional training to help give you --` favor. Either way, it's government - pride and confidence. certified proof of specific * * * knowledge and skills! More than half of CIE's If you talked to some of our courses prepare you for the graduates, chances are you'd find a When you build your own government -administered FCC lot of them shopped around for 5 MHz Triggered -Sweep, License exam. In continuing their training. They pretty much Solid -State Oscilloscope surveys, nearly 4 out of 5 CIE knew what was available. And they you take your first real professional graduates who take the exam get picked CIE as number one. step. You use it as a doctor uses an their Licenses! X-ray machine- to "read"

Why you should shop . waveform patterns... Shop around...but send around yourself. lock them in...study, understand for CIE's free school We hope you'll shop around. and interpret them! catalog first! Because, frankly, CIE isn't for When you get your Mail the card. If it's gone, cut everyone. Digital Learning out and mail the coupon. If you There are other options for the prefer to write, mention the name hobbyist. If you're the ambitious Laboratory you'll be into digital theory-essential and date of this magazine. We'll type-with serious career goals in send you a copy of CIE's FREE I raining today for anyone electronics-take a close look at school catalog-plus a complete whát we've planned for you at CIE. package of independent home study information! For your convenience, What you should we'll try to have a representative look for first. ;r,fr7 ' contact you to answer your questions. Mail the card or Part of what makes elec- coupon-or write: tronics so interesting is it's 1776 17th t11151 e --sarG CIE, East St., based on scientific discover- Cleveland, OH 44114. ies-on ideas! So the first thing to look for is a program that starts with ideas and builds on them! That's what happens with CIE's Auto -Programmed® CIECleveland Institute who wants to keep pace of Electronics, Inc. Lessons. Each lesson takes one with the state of the art of helps you 1776 East 17th Street. Cleveland, Ohio 44114 or two principles and electronics in the eighties. With Accredited Member National Noma Study Council master them-before you start CIE's Digital Lab, you'll be using them! in dozens fascinating YES...I'm shopping around for applying of 1 the right kind of career training in ways the theory you've learned. For electronics troubleshooting-and CIE How practical example, you'll compare analog sounds well worth looking into. Please and digital devices. You'll learn to send me my FREE CIE school is the training? catalog-including details about make binary to decimal conversions troubleshooting courses- This is the next big important and to work with semiconductor question. After all, your career will plus my FREE package of home study devices and circuits. You'll see how information! PE -14 be built on what you can do-and digital equipment is vital in today's on how well you do it. 1 Print Name ways exciting, growing fields such as Here are some security where digital of CIE's trouble- theory provides the Address Apt shooting programs brains for space-age 1 City help you alarm and protective get your devices. State Zip "hands-on" Of course, CIE training... Age Phone offers even more 1 (area code) With CIE's advanced training Check box for C.I. Bill information: programs, too. But the Veteran Active Duty Personal main point is simply this: Mail today! Training 1

Laboratory... 1 29

AmericanRadioHistory.Com 1 GHz For Only. $139.95 8'-Digits 1 JPPM TCXO° o' ,Factory Wired 500 MHz or 1 GHz

951 WIRED $1' 39, $109-915500 WIRED . 50 Hz to 1 GHz 50"Hz°tó 512'MHz. 53 H: - 312 MR: FREQUENCY COUNTER

. 1 Hz Résolution''to 50 MHz. O. S' l 1 Meg Ohm, 50 Ohm, BNC ' 15 MV Sensitivityat 250 MHz M. _IIR a, v 'O Inputs Typ. PI Model 5500 ,

With thelntroduction of the 5510 DSI hasdilled a long standing void in the frequency counter market place. You now have the choice óf Selecting a 512 MHz model 5500 for $t10 or for only $30.00 more you can buy an 8 digit 1 GHz counter model 5510. With this 1GH1capa- bility, the new world of 960°MHz is ,immediately available to°you. Both the'5500 and 5510 are available with a rechargeable battery pack which includes the AC adapter and battery°charger for one low price. Whether you select the 5500 or the 5510,.you will receive the best price to quality features ratio in. the industry. No wonder DSI has become one'of the world's largest manufacturers of freq. counters.'

1.2-':GHZ Only $1.99,.512. MHz. 'Only $16995 ° 5612 KIT ' ` 5600 KIT d

10 MHz 'Proportional' Oven 50 Hz - 512 MHz , FREQUENCY COUNTER ..2 PPM 10° to 40° C Time 1 111 f9 1 Base , -Ii ir ) 1 I I Lt .1 Hz Resolution to 50 MHz.

External 10 MHz inputs A. S10Y =Te 9:119 © outputs. 1 e! .. 9 Bright .5 inch LED Read- U outs. ti.. Model 5600A LResMut^ *100%100% Factory Tested SehüJ 'rY4 SliLLy SC YM::S1Svlt Kits 95% Factory Assembled. l 50 Ohm, 1° Meg,`BNC Inputs . 10.MV Sensitivity at 250 MHz ' .

TYP °

Whether you select a 5600, 5612.Kit with 95% of the assembly completed by DSI or select a factory wired and calibrated frequency counter, you can count on DSI to solve all those difficult bench or field problems from measuring audio signals to chécking a 960 MHz mobil radio (model 5612), servicing a VTR, trouble shooting a PLL signal in a TV ór FM radio, etc. The 5600 or5612 has the sensitivity and accuracy to meet any FCC landmobile, broadcast, RF, or telecommunications requirements. DS/ offers a10 HR rechargeable battery pack (BA56) option, and an audio multiplier (AM56) which will allow you fo resolve a 1/1000 Hz signal in only ten seconds or 1/100 Hz signal in one second. DSI 5600 series offers just the right instrument for all your communication RF, TV servicing and industrial testing needs. FOR INFORMATION -DEALER LOCATION - ORDERS -°OEM CALL 800-854-2049 CALIFORNIA RESIDENTS CALL 800-542-6253

Accuracy S`érü18vity Typ Frequency Number Power Range Typ Over of Size Temperature @ @ Requirements N W D 50-250MHz 250-450MHz Readouts 5600A -Kit $169.95 Proportional SOHi-55OMi'iz Oven 115 VAC or 2 PPM 10° - 10-25mv 10-15mv 15-50mv 9 3/. x 91/25,,x 9 5600A -Wired $199.95 40°C 9 2-14.5 VDC . 5612Kit $199.95 P ortional Oven' '115Pao VAC or 50H;-1.2 GHz 10-25mv 10-15mv 15-50mv 9 .2 PPM 10° - 40°C VDC ' 3'/." x 9w' x9" 5612 Wired $239.95 - 8.2-14.5 5500 _.. Wired $109.95 50Hz-512MHz " 115 VAC or 10-25mv X15-25mv - 8 1 TCXO- 25-75mv 8.2-14.5 VDC PPM 17°P x 5510 Wired $139.95 50Hz- GHz 40°C 11/2" x 5" 5h" - or NICAD PAK. Prices effective Factory wired un'ts carry 1 year limited warranty kits carry a 90 day limited warranty. 'With AC -9 Adapter Prices and/ºr specifications subject to change without notice or obligation. March 1, 1980 °

I VISA* master charge 5510 Wired 139.95 5500 Wired 5612 Kit 199.95 109.95 DSI INSTRUMENTS, INC. 5612 Wired 5510/BAC Wired ° 164.95 239.95 9550 Chesapeake . Drive 5600A Kit 169.95 5500/BAC Wired 134.95 San Diego, California 92123 5600A Wired 199.95 T600 BNC .ANT (all models') 7.95 (714) 565-8402 r) AC BA56 Rechargeable -9 AC Adapter(all models). 7.95 .. TERMS: MC - VISA - AE -CHECK - M.O. - COD in U.S. Funds. Please add 10% to a maximum of $10.00 10 Hr. Bat. Pack ,. :. 29.95 LC 5000 169.95 for shipping, handling and insurance. Orders outside AM -56 Audio Multiplier of USA & Canada, please add $20.00 additional to INTERNAL BAT. ONLY AC -9 NOT REQUIRED. cover air,shipment. California residents add 6%Sales Tax .001 Hz Resolution , 34.95 CIRCLE NO. 20ON FREE INFORMATION CARD AmericanRadioHistory.Com Julian Hirsch Audio Reports

and for some program material. The IN position gives fast response, so that the display can follow brief program peaks. Final- ly, there is a small INPUT LEVEL knob, with a center detented CAL position. The CAL detent lets the C-101 display actual SPL ------" readings from the microphone. This control is calibrated at 5 -dB intervals over a ±20 - i -Aa`+ dB range and can be used to extend the _ _ .;. - S ,rt . .. +2." a 'range of sound -level meter readings to cov- + ----'- ' --_e_,-,'rtS ', ,_ ...... i --!. T er 40 to 132 dBA. It also serves as an .. .. us ,`" `_- _`. input -level control for the spectrum -analyzer and program -level indicator functions. There are phono jacks for the line inputs and outputs, and a second set of jacks for the tape recorder inputs and outputs on the Audio Control Model C-101 rear apron. Two phono jacks carry the pink - noise test signal, whose 100 -millivolt level is suitable for driving high-level inputs of an graphic equalizer and amplifier. Below them is a standard 1/4" (6.4 -mm) jack into which the microphone plugs for making acoustic SPL measure- spectrum analyzer ments and adjusting room equalization. The RTA cisplay automatically switches from the electrical program to the microphone output when the mike is plugged in. The Audio Control Near the equalizer switches is a TAPE The microphone is a miniature condens- HIRSCH- Model C-101 com- MONITOR button that replaces the one on the er type with built-in active circuits powered HOUCK bines a- ten -band amplifier to which the C-101 is connected. by a 5 -volt supply that reaches it through graphic equalizer Included in the unit are two rumble -reducing the signal cable. A typical calibration curve - with a real-time features that are effective even when the supplied with the microphone reveals a spectrum analyzer, equalizer circuits are bypassed. The SUB- response within ± 1.5 dB from 30 to 20,000 whose filter bands correspond to the SONIC FILTER cuts off below 20 Hz at an 18 Hz and a ± 3 -dB tolerance on its sensitivity adjustable frequency segments of the dB/octave rate, and the RUMBLE REDUCER rating. This caliber of performance is more equalizer. The two parts of the instrument suppresses vertical (out -of -phase) rumble than adequate for the intended use of the are functionally separate, but their use can by summing the two channels at frequen- instrument, although professional SLMs be coordinated by appropriate settings of cies below 200 Hz. This has virtually no typically have closer tolerances. It appears the various controls. effect on stereo directionality or total bass that the Audio Control microphone (or a Usefulness of the C-101 as a tool for energy, since most bass program content pair of them) should make a fine adjunct to adjusting a home music system is greatly is common to both channels. a tape recorder, but the manufacturer cau- enhanced by its built-in pink -noise genera- The right third of the front panel is tions against trying to use it with anything tor and inclusion of a separate high -quality devoted to the real-time spectrum analyzer but the C-101, or to plug any other kind of condenser microphone whose output can (RTA), whose display contains 90 red microphone into the C-101. Audio Control's be displayed on the spectrum analyzer. It LEDs in a rectangular grid pattern (10 col- microphone requires a +5 -volt power sup- also converts the C-101 into an audio umns of nine (LEDs). Each vertical column is ply; and since that voltage is present at the sound pressure level, or SPL, meter. labeled to correspond to one of the equal- C-101 jack, another microphone plugged The compact Model C-101 measures izer bands, from 32 to 15,500 Hz. Intervals into it might be damaged. 19"W X 61/2"D X 31/2"H (438 X 165 X 89 between the level -indicator diodes can be mm) and weighs 63'4 lb (3.1 kg). The panel set to either 2 or 4 dB by the RANGE Laboratory Measurements. We meas- is slotted for mounting in a standard EIA switch. The center horizontal row of LEDs ured the equalizer's frequency-response rack. Suggested retail price is $549. is calibrated át 0 dB, and the display range Contours with the controls at their extreme about that line is either ±8 or ± 16 dB. In settings. Each filter has a Q of 2.5, which General Description. About two thirds of the RTA mode, a row of green LEDs minimtzes the interactions between adja- the front panel is devoted to the graphic appears at the 0 -dB level that separates cent controls, although some still occurs. equalizer sliders. Left and right channel the octave bands. The "flat" frequency response of the controls for each band are adjacent, with Below the POWER switch is a FUNCTION equalizer section was excellent, producing detents at the center (flat) positions and a button that engages the real-time analyzer virtually no alteration of the shape of a

nominal range of ± 12 to 15 dB. Each con- when pushed in (RTA). When it is out, the 1 -kHz square -wave signal. With the equal- trol has a scale calibrated from + 15 to display indicates total level across the izer bypassed, the frequency response - 15 dB in 3 -dB intervals. Center frequen- audio band, appearing as a horizontal line was down only 0.1 dB at 5 and 50,000 Hz cies of the equalizer bands are at 32, 60, of red LEDs whose vertical position varies and down 0.3 dB at 100,000 Hz. (The man- 120, 240, 480, 960, 1920, 3840, 7680, and with program level. A third amplitude scale, ufacturer's rating is ± 0.75 dB from 3 to 15,500 Hz. at the right of the display, labeled SPL and 100,000 Hz.) Two small pushbutton switches, labeled calibrated from 60 to 92 dB at 4 -dB inter- The SUBSONIC filter reduced the output by EQUALIZER PROGRAM and EQUALIZER TAPE, Con- vals, is used when the microphone (sup- 3 dB at 20 Hz, below which we did not nect the equalizer circuits in the signal path plied with the C-101) is plugged into a measure the slope. The RUMBLE REDUCER or in the outgoing signal path to a tape rear -panel jack to convert the C-101 into a had the claimed effect, although the recorder connected to jacks on the rear of sound level meter (SLM) that indicates in amount of reduction depends on the source the C-101. The buttons are mechanically dBA (A -weighted) levels. The RANGE switch of the rumble (lateral rumble is not interlocked so that either one must be must be set to 4 dB for SPL readings. affected). Oscilloscope photos (Figs. 1A released before the other can be pressed. With the DISPLAY ACTION button in its OUT and 1B) reveal the outputs of the C -101's The ability to equalize a program before it position, response of the LED indicators is left and right channels, with only the left is recorded is a useful feature that is rarely slow, which is convenient for making mea- (Continued on page 32) found in today's graphic equalizers. surements with the pink -noise test signal

MAY 1980 31

AmericanRadioHistory.Com HIRSCH REPORTS continued

Fig. 1. Oscilloscope photos of equalizer output with square -wave input and Rumble Reducer out (A) and in (S).

channel driven by a 100Hz square wave. In amplifier was 0.575 volt for a 0 -dB (center) described in the very complete user's man- Fig. 1A, the RUMBLE REDUCER IS not engaged. reading using the CAL position of the INPUT ual. Although the C-101 is less precise With it engaged (Fig. 1B), the signal is LEVEL control. At its maximum setting, this than professional instruments usually em- present at equal levels in both channels control enabled a 15.6 -millivolt input to give ployed.for making equalizing adjustments, because of the summing action of the cir- a 0 -dB reading, while at its CCW limit, it was it is quite adequate for the job. cuit. Alterations of the square -wave able to turn off the display completely. We experimented with equalizing sev- shapes in the two channels result from the eral very different speaker systems with fact that summing begins at about 200 Hz User Comment. We have used many the microphone close to our normal listen- and produces some phase shift that is not graphic equalizers that were normally ing position. We found that the C-101 could identical between channels. As phase adjusted only by ear, using musical pro- produce a nearly flat frequency response errors are complementary, the audible program material or a pink -noise test record from any of them in less than five minutes. It gram (sum of the channels) has the same playéd through a phono system. Neither did not make all the speaker systems waveform as the original signal. scheme gives assurance of a properly bal- sound alike, but certain settings of the slide Harmonic distortion is rated at no more anced system, since the human ear is controls were common to all our test than 0.025% at a 1 -volt output from 20 to simply not an accurate enough sensing speaker systems, which is clear evidence 20,000 Hz. We measured it at 1000 Hz and device. Hence, it is reassuring to know that of room resonances that had colored the obtained readings of 0.003% to 0.0045% an equalizer/SLM system like the Audio sound of all speaker systems heard in that for all output levels from 0.1 to 5 volts and Control C-101 is available and can elimi- room. After equalization, all the speaker 0.006% at 7 volts. (The output of this unity - nate guesswork. systems sounded much "cleaner." gain system clipped at 7.3 volts when driv- The C-101 is the first equalizer we have The C-101 is actually a combination of ing the IHF standard load of 10 kilohms in seen that permits a simple, accurate equal- the company's Models C-22 octave -band parallel with 1000 picofarads.) Output ization of one's speaker systems and lis- equalizer and C -50A real-time analyzer with noise level was below our minimum meas- tening room. Adjacent placement of left and pink -noise generator and microphone. With urement capability of 80 microvolts (un - right channel sliders simplifies operation, the two combined in a single, very compact weighted), or -82 dB relative to 1 volt. and the calibrated microphone makes it a unit, the C-101 is more convenient to use

The publishéd spec is 90 dB below 1 volt in matter of a few minutes' easy work to flat- and costs $100 less than the separates. a 10 -kHz bandwidth. ten out the response of a music system If you are seriously considering getting Center frequencies of the 10 octave - better than one might have thought possi- an octave band equalizer, we urge you to band equalizer filters were typically within ble. The spectrum analyzer then provides look closely at the C-101. With other equal- 5% of the nominal values. Amplitude cali- continuous display of program level or izers we have used, one has little chance bration of the LED display was good, spectral content and serves as a means of d getting an optimum adjustment of room although intervals of 2 or 4 dB between comparing records, phono cartridges, tape or speaker -system response, but with the steps resulted in some ambiguity in the recorders, etc. Numerous other applica- Audio Control C-101, it is hardly possible readings. However, for their intended pur- tions, such as the use of the C-101 to set not to get a equalized system. pose, reading precision and accuracy was up the bias on a cassette recorder, are CIRCLE NO. 101 ON FREE. INFORMATION CARD satisfactory. (More Reports on page 34) Calibration of the SLM display, using the microphone, was checked with the pink - noise test signal through several speaker systems in a side -by -side comparison against our Scott 450B SLM. When the INPUT LEVEL control was set to CAL, -the C - 101's SPL readings were high by 4 to 10 dB (typically about 6 dB). When the INPUT LEVEL control was used to match the C-101 reading to that of the Scott meter at the 0 -dB level of 76 dBA, the indications were i 11 f -accurate across the full display range.

(This required a -5-dB setting of the knob { ' on our test unit.)

We analyzed the spectrum of the pink - noise test signal on our H -P 3580A spectrum analyzer, using a logarithmic frequency sweep from 20 to 43,000 Hz. Figure 2 shows that the energy spectrum slopes downward with increasing frequency at a rate of 10 dB per decade (3 dB/octave) in accordance with the defined spectrum of pink noise. Sensitivity of the LEVEL display to an Fig. 2. Spectrum analysis of the C-101's pink -noise test signal electrical input signal from the associated using a logarithmic sweep from 20 to 43,000 Hz.

32 POPULAR ELECTRONICS

AmericanRadioHistory.Com The VIP hobby computer: Start programming for only $99.

N, IYE11 NSM.0 tor M-111 ' - ....then Mru.x 0110 a $ '19° 1.3 s ill! !'-rn -c --i'- `;,t... iY:=* - , _' w' r^ . - ,IÍtIIIIIIIjO jj 0000'' f >b 0000 0000 0000 ^ r' ,,T" t - nch; ' _f Cósuac5.'° g

New! VP 111 New low price! COSMAC VIP lets you add Microcomputer.... 9 9. The original VIP ..199 computer power a board Assembled* and tested. Completely assembled at a time. Features: and tested. With easy -to -buy options, the versatile VIP means even more RCA 1802 Microprocessor. All the features of the VP -111 plus: RCA COSMAC More challenges in 1K Bytes static RAM. A total of 2K Bytes static RAM. excitement. and control functions. Expandable on -board to 4K. Power supply. graphics, games For everyone, from youngster to serious Expandable to 32K Bytes total. 8 Bit input port. hobbyist. 512 Byte ROM operating system. 8 Bit output port. CHIP -8 interpretive language or I/O port connector, Built around an RCA COSMAC micro- machine language programmable. System expansion connector. processor, the VIP is easy to program Hexidecimal keypad. Built-in speaker. and operate. Powerful CHIP -8 inter- Audio tone generator. Plastic cover. pretive language gets you into Single 5 -volt operation. Three comprehensive manuals: programming the first evening. Video output to monitor or modulator. VIP Instruction Manual -20 video Complete documentation provided. Cassette interface -100 Bytes/sec. game listings, schematics; much more. Send the coupon now... Instruction Manual with 5 video game VIP User's Guide-operating instruc- Complete the coupon below and mail to: much more! listings, schematics, CHIP -8, tions and CHIP -8 for the beginner. RCA VIP Customer Service, New Ideal for low-cost control applications. RCA 1802 User's Manual (MPM- Holland Avenue, Lancaster, PA 17604. Expandable to full VIP capability with 201 B) - complete 1802 referenceguide. Or call toll free (800) 233-0094 VP -114 Kit. to place your Master Charge or VISA 'User need only connect cables (included), a credit card order. In Pennsylvania, 5 -volt power supply, and speaker. c call (717) 397-7661, extension 3179. Please send me the RCA COSMAC VIP items indicated. VP -560 VIP EPROM Board-Interfaces two VP -611 ASCII/Numeric Keyboard-Same numeric Price 2716 EPROMs to VIP $ 34 as VP -601 plus 16 key Type Description keypad $ 89 Microcomputer VP -565 VIP EPROM Programmer Board- O VP -111 New low cost O VP -620 Cable: Connects ASCII keyboards (See description above) $99 Programs 2716 EPROMs. With software $ 99 to VIP. $ 20 VP -114 Expansion Kit for VP-111-Includes VIP Expansion 4 0 VP -700 VIP Tiny BASIC ROM Board-BASIC 3K RAM, I/O Port and connectors $ 76 VP -575 Board-Provides buffered and one unbuffered code stored in 4K of ROM. $ 39 -711 VIP-The original VIP Microcomputer VP expansion sockets. $ 59 0 VP -710 VIP Game Manual-Listing for 16 (See description above) $199 VP -576 VIP Two -Board Expander-Allows exciting games $ 10 RAM On -Board Expansion Kit-Four O VP -44 use of 2 Accessory Boards in either VP -720 VIP Game Manual-II-More exciting 2114 RAM IC's. Expands VP 711 I/O or Expansion Socket $ 20 games (Available 2nd qtr. '80) $ 10 memory to 4K bytes S 36 VP -601 ASCII Keyboard -128 -character O MPM- CDP1802 User Manual-(Included VP -590 VIP Color VIP to Board-Converts ASCII Encoded alphanumeric 201B with VP -711)' $ 5 color. Four background and eight keyboard. $ 69 foreground colors $ 69 0 Please send more information - VP -595 VIP Simple Sound Board-Provides handling charge of $3.00. 256 programmable frequencies. For Enclosed is S for items checked plus shipping & simple music or sound effects. Add your state and local taxes $ Total enclosed $ Includes speaker 6 30 Americard I enclose check or money order or, charge my E VISA/Bank VP -550 VIP Super Sound Board-Turns your VIP into a music synthesizer! Two O Master Charge. independent sound channels. On- Credit card account No. board tempo control. Outputs to Master Charge Interbank No. Expiration date' audio system S 49 for orders): VP -570 VIP Memory Expansion Board- Signature (required credit card Plug-in 4K RAM memory 6 95 Name (please type or print)' VP -580 VIP Auxiliary Keypad-Adds two - player interactive capability. 16 -key Street address: City keypad with cable. Connects to sockets on VP -590 or VP -585 S 20 State & Zip: Telephone: VP -585 VIP Keypad Interface Board-Inter- Make checks payable to RCA Corp. Prices and specifications are subject to change faces two VP -580 Auxiliary Keypads to VIP $ 15 without notice.

POPULAR ELECTRONICS CIRCLE NO.63 ON FREE INFORMATION CARD 33

AmericanRadioHistory.Com HIRSCH REPORTS continued and a minimum of 5 ohms between 100 and 400 Hz. It rose smoothly to between 8 and 12 ohms at all frequencies above 1000 Hz. Sensitivity was almost exactly as Electro -Voice Interface:2 rated, although our measurement used an octave bandwidth (about 700-1400 Hz) to

E -V's 300 to 10,000 Hz. With 1 watt of drive Series II speaker system (2.83 volts), the SPL at 1 meter was 91 dB, which is relatively high for a small vented system.

Bass distortion was very low. At 1 watt input it was between 0.5% and 1% from 100 Hz down to below 50 Hz, rising to 2% ^ry takes the form of a passive radiator, a 12" at 40 Hz and 6% at 30 Hz. Increasing the (305 mm) passive cone. Acoustic cross- drive to 10 watts had only a moderate over between the driven and passive cones effect down to 55 Hz, 'where distortion occurs at 66 Hz. Tweeter level is contin- remained under 2°/o. However, it was uously variable over a 6 -dB range. (Maxi- greater at lower frequencies -8.5% at 40 mum output is in the "flat" position of the Hz and 14% at 35 Hz. control.) The rated anechoic frequency response User Comment. We preferred the sound of the Electro -Voice Interface:2 Series II is' of the E -V Interface:2 Series II, with the ±3 dB from 47 to 18,000 Hz. Its total tweeter level maximum, although a "more acoustic power output is ráted at ± 3.5 dB reflective" listening room might have _flL from 47 to 12,500 Hz. The rated sensitivity changed our opinion. Initially, we installed is 92 dB SPL at 1 meter when driven by the speakers on 7" high stands and placed 1 watt into its ,s--- nominal 8 -ohm impedance. them on a carpeted floor about a foot from the wall. The a s result was heavy quality Laboratory Measurements. When we that did not correlate at all Yi ,1 1 with the meas- spliced our reverberant field response ured bass response. Placed on a shelf measurements to a close-miked woofer against the wall and at ear level, the response curve, correcting for room ab- speakers sounded vastly better. Deep sorption, we found the overall composite bass was evident in amounts that were frequency response to be remarkably hard to credit to such a small box, without close to the specifications in the instruction overemphasis of the upper bass. Balance booklet-actually better in many respects! between midrange and high frequencies The composite curve was within ±3.5 dB was excellent. from 55 to 20,000 Hz with the tweeter con- E -V devotes considerable space in the trol at maximum and within ±3.5 dB from instruction booklet to the criteria for posi- 40 to 20,000 Hz with the control at mini- tioning these speakers. We suspect that mum. Response at middle and high fre- some care and experimentation in this quencies was very uniform.. A slight rise of area will pay dividends, as One of the least the speakers about 2.5 dB was found at 13,000 Hz, but may be more sensitive to placement HIRSCH- expensive models in than limits of ± 1 dB applied from 800 to 10,000 most others. HOUCK the Electro -Voice Hz. Reducing the tweeter level control set- Overall, "Interface" Series the Interface:2 Series II speak- ting tipped the curve downward above ers sounded t of speaker systems smooth and uncolored. There 1000 Hz. was no 'trace is the Interface:2 of stridency, boom, or artifi- Woofer response was impressively flat, cial midrange coloration. Only Series II. Like the rest of the line, it has after we had except for a small rise at 1000 Hz that may decided this been designed to make the most effective that was a good speaker on have been due to speaker placement. its merits, did we use of a small vented enclosure and com- look up the list price- From 800 Hz lo 55 Hz, total amplitude vari- and received our second patibly designed drivers. It differs from the surprise of the ation was only 1.5 dB. Output fell off day. Even a few years a more expensive Interface speakers in that ago pair of these smoothly below 55 Hz. would have been a it does not require an equalizer. It is rela- bargain at twice the The impedance curve of the Interface:2 present price. tively efficient and is recommended for use Allowance for 1980's in- Series II had the "double humped" shape flated with amplifiers rated between 3.6 and 250 currency shows them to be an excel- typical of vented enclosures, with maxima watts per channel. lent value indeed. of 30 ohms at 34 Hz and 22 ohms at 75 Hz, Each system weighs 25 lb (11.3 kg.) CIRCLE NO. 102 ON FREE INFORMATION CARD (More Reports on page and is housed in a simulated walnut - 36) grained vinyl cabinet, measuring 241/4" X 133'4' X 103/4' deep (616 X 350 X 273 100 mm). The black cloth is in grille held place 50 by Velcro fasteners. Binding -post terminals are recessed into the rear of the cabinet. 30 ar 2 Nominal impedance of the speaker is 8 20 ohms, with a minimum rating of 5 ohms. Preferred operating position is close to a _-. É 10 fr wall, at ear level; but, for floor mounting, a pair of 8" -high (200 -mm) accessory stands ó is available from Electro -Voice as the Mod- 5 el BBR-1. Suggested retail price of the 3- interface:2 Series II is $160. 2

General Description. Interface:2 Series II is a two-way system, with an electrical

crossover at 1500 Hz between a 1192' (37 .00 00 mm) dome tweeter and an 8" (200 mm) FREQUENCY (Hz) woofer/midrange driver. Because of the small size of the enclosure, the "vent" Impedance curve shows rated minimum of 5 ohms.. 34 POPULAR ELECTRONICS

AmericanRadioHistory.Com croc

d s:aa-- a : . I.f`Ó ! á I- ! !? M. 4 a .' j ` Ts1

,___-'®a :,. ? ' .r.r.. - 9t : ::7' oL_ -...... (:

.`*MI B

CM -600., $6.95* RW-50.$2.98* NEW 'CM -000 SOLDERLESaPROTOT.YPE BOARD - CM- 600 is aunique system for solderless.construction of circuit protótypes, useful to both engineers and hobbyists. The CM -600' is a neoprene board 41" (114mm) x 6" (152min) with 2280, holes an .100" (2.54mm) centers. Standard components including DIP's are mounted by simply inserting leads into the holes in the long life neoprene material. Interconnections are easily made using 20 or 22 AWG (0,8 or 0,65mm) wire jumper. Positive contact is assured by the elasticity of the hole, which compresses the leads together. To remove components or leads, simply pull out. This facilitates easy circuit changEs making it ideal for breadboarding experimental' 'Circuits. CM -600 also features numbered rows and columns for easy reference. Accessory it RW-50 contains 50 pcs of AWG 20(0,8mm) insulated jumper wires of assorted lengths from 1"(13mm) to 4"(1001p.m). Both ends are stripped and bent 90° for _easy insertion. In stock directly from OK-Machine:et Tool Corporation 3455.Cc nnér St:, Bron c,N.Y..10475 U.S.A:. Tel. (212)994-6600 Telex 125091'

* Minimum billings $25.00, add shipping charge $2.30 New York State residents add applicable tax

POPULAR ELECTRONICS CIRCLE NO.47 ON FREE INFORMATION CARD 35

AmericanRadioHistory.Com HIRSCH REPORTS continued User Comment. In our listening tests, the Nagatron 350E.held up very well. It gave no signs of mistracking on any music record. There were no audible signs of the 16,000 - Nagatronics Model 350E Hz stylus resonance, which was quite small in amplitude and higher in frequency than most of the music. Specific sound charac- stereo phono cartridge ter that could distinguish this from many other fine cartridges was absent. In fact, the Nagatron and a number of other cartridges (all considerably higher in price)

: The Nagatron 350E With the CBS STR 100 test record, the HIRSCH= is one of a series p: frequency response was flat within 1 = HOUCK ± dB of induced magnet from 40 to 10,000 Hz, rising to a maximum stereo phono car- of about +3 dB at 16,000 Hz before return- that a Cli RÍ tridges share ing to the midrange level at 20,000 HE. and ::a-:: n' common body Channel separation was symmetrical be- differ only in their stylus systems. The tween channels and measured typically 23 user -replaceable stylus assembly of the to 25 dB at all frequencies up to 15,000 Hz, .t Nagatron 350E uses a 0.3 X 0.7 mil (76 X remaining strong up to 20,000 Hz. ter iDlti.a;i;.li NCe ' 178 micrometers) elliptical diamond, nude Low -frequency resonance in the test _R44 , '. mounted to a cantilever made of highly arm was at 9 Hz, with an amplitude of 9 dB. rigid aluminum alloy. The molded plastic Square -wave response from the CBS case has been designed to minimize inter- STR 112 record showed a single overshoot nal resonances, avoiding coloration of the and well -damped low-level ringing at the reproduced sound from that source, and 16,000 -Hz stylus resonance frequency. 10000 has a super-permalloy shield to minimize Tracking our high -velocity test records was FREQUENCY IN CYCLES PER SECOND hum induction by external fields. Weighing good at 1.8 grams-and, in most cases, at 6.1 grams, the Model 350E has standard 1.5 grams. The cartridge was able to play Response between 3 and 15 kHz 1/2 -inch (12.7 -mm) mounting centers. Its the 60 -micron level of the 300 -Hz tones on changes less than 1 dB with suggested retail price is $95. the German Hi -Fi Test Record at 1.8 grams capacitance variation of 175 to 375 pF. and the 70 -micron level at 2 grams. Output General Description. The fixed samar- voltage was about 3.1 millivolts at 3.54 were a's a rule indistinguishable by sound ium -cobalt magnet of the Nagatron 350E cm/s velocity, with the channels balance and generally showed no intrinsic quality cartridge is located outside its permalloy within 0.4 dB. differences. shielded structure, isolating the coils from The Nagatron 350E did an excellent job Though not everyone will see it this way, its magnetic field except for the component in tracking distortion tests using the Shure the relatively low compliance of the 350E is modulated by the ferrite armature coupled TTR 102 and TTR103 records. High -fre- an advantage that makes it a good match to the stylus cantilever. According to Naga- quency tone bursts of the TTR 103 were for any of the numbers of tonearms having tron, samarium -cobalt magnets have better tracked with a distortion level not exceed- medium to high effective mass. The 9 -Hz long-term stability than other types. As a ing 1%o even at the record's maximum level resonance frequency we measured in our result, the output of the cartridge does not of 30 cm/s. At 15 cm/s, it was 0.6%. On 15-gram test arm underscores the benefit vary after extended use. the IM bands of the TTR102, the reading of this compatibility-it is close to the The pivot of the stylus cantilever, sup- was 2 to 3°/o. (Few cartridges can track the optimum frequency for tracking record ported by a block d elastomer, is very 27-cm/s maximum level on this record.) warps without affecting the low bass close to the armature: When the stylus In the subjective tracking tests using the response. In most arms, this cartridge assembly is inserted into the cartridge Shure "Audio Obstacle Course" records, would not resonate below about 8 Hz, nor body, the armature bridges the gap the 350E was competent though not out- above 11 or 12 Hz. In other words, the between the exposed pole of the fixed standing. On the ERA Ill record, we heard a Nagatron 350E can be depended upon to and the magnet two internal pole pieces trace of mistracking on the highest level 01 function well in nonexotic tonearms and that channel the flux through the fixed coils the sibilance and bass drum sections. On with almost any amplifier's input capaci- in the body. the ERA IV record, there was definite mis tance. These characteristics, with its fine Rated effective tip mass of the Nagatron tracking on the maximum level (#5) of al sound and moderate price make it a strong 350E is 0.65 milligrams. Intended tracking bands except the solo harp, and traces o' mainstream contender. force is from 1.5 to 2.0 grams (1.8 grams mistracking on level 4 of most bands. CIRCLE NO. 103 ON FREE INFORMATION CARD optimum). Output at 1 kHz for a 5 cm/s velocity is rated at 4 millivolts, and channel

levels are said to be balanced within 1 dB. Frequency response is stated as 10 to ;1 :L11. 25,000 Hz with no tolerance given, and rated channel separation exceeds 25 dB at 1 kHz. Recommended load is 50,000 ohms in parallel with a capacitance of 200 to 400 picofarads.

Laboratory Measurements. We installed the Nagatron 350E in a moderately low -mass tonearm (less than 15 grams) for testing. Preliminary frequency -response measurements with different values of load capacitahce indicated that it was not criti-

cal. There was less than 1 dB change in high -frequency response (between 3,000 and 15,000 Hz) over a capacitance range from 175 to 375 picofarads. The latter value was used for the subsequent tests. Frequency response and crosstalk for left and right channels. 36' POPULAR ELECTRONICS

AmericanRadioHistory.Com - i y pt-

- it on.

You came out of the service with, a lot going for you. Skill. Knowledge. And experience. And much of it didn't come out of a book or a tech manual. It came from, 4.. sometiiody else. Somebody who, the time s . - took to pass what he knew. ."`..)11111111' .. along `.,:. . Well, what about you? M rol000ffooM You've got a lot to give, too._ And you ,cando ít. Part-time. . In the Army. National Guard. In the Army Guard, you can make a difference. By working with people who :° -: I .:' A..

- , ,,,. , want to know what you know. . By showing them the ropes. And watching them grow. Its a satisfying job. The pay's good, too. And you'll be putting time against retirement benefits. Check ít out. There are a lot of people who want what you've got. Pass it on. In the Army National Guard. See your local recruiter os call toll -free 800-638-7600 ARMY (except íñ Alaska, Hawaii, Puerto Rico and the Virgin Islands). In Maryland, call NATIONAL 728-3388. Helpsomebody. GUARD Including yourself: The Guard belongs. CIRCLE NO. 43 ON FREE INFORMATIOA CARD

AmericanRadioHistory.Com V

.5.1-3 -9 a '1ao d ' ev r,14ElpeTE f z.", J r. ' qt . -.ry i µtly 2:5r.:./ °KiR9e WTE(p - / M1.J ® - 1? FtpR4NETR1 Nu".. 5 9 ,.....wr. Mlw1 1 W,L Yy pRE55 . n. Iva r; . /tY. . Tf WYE RJTlarlE /J.

iw , +i.a WA - - - yM _. / - "".?~Í " 41 áfroV.5^

-'-QE^i -t-_.rTK_S. Z'

Let up-to-the-minute`- - weather reports from yóurÓwñ Heatlikit Digital Weather Computer. Heathkit imagination applied to micro-_ a touch of class to any home. Weather Fun to build: Like all Heath electronic processor electronics brings you a. information is- relayed to -the -consolé kits, the Digital Weather Computer personal weather computer that mon- from a special transmitter that mounts comes with its own easy-to -follow as- itors current weather, keeps track of " On your TV antenna mast. sembly manual that guides you step- changes and stores past data - and by-step through every phase of as- puts it all at your fingertips. sembly. Anyone can do it. The Digital - Just push a button to get: Weather Computer is also available Indoor and outdoor temperatures in completely assembled and tested. - Fahrenheit or Celsius Wind speed, both average and gusts, in mph, kph or knots Free Wind direction Catalog Barometric pressure and rate of change The transmitter features a unique infra- Complete details and - Wind chill factor red sensing- device for greater sensi- price on the Digital tivity and accuracy. A special-piezo re- Weather Computer are Time and date - sistive 'silicon bridge transducer senses in the new Heathkit Catalog, along with Memory stores highs and lows and the the 'slightest changes in barometric descriptions of nearly 400 electronic times they occurred, Data remains in pressure. For serious weather research, kits for your home, work or pleasure. memorj for as long as you want, ready the Heathkit Digital Weather Compute& Send for free or be your catalog today to recalled at the push of a button. can interface with chart recorder or dig= pick one up at your Heathkit Electronic Handsome solid walnut console adds. ital computer. Center.*

Visit your Heathkit Electronic Center where Heathkit Products ® are displayed, sold and serviced. See your telephone white pages for the location nearest you. Heathkit Electronic Centers are qp. units of Veritechnology Electronics Corporation. 1'lIt kl MAY 1980 t CIRCLE NO.69 t ON FREE h INFORMATION a CARO Write to Heath Company, Dept. 010-654, Benton Harbor, MI 49022 GX-377 AmericanRadioHistory.Com Popular Electronics by George Meyerle MAY 1980

Part 1 of a series devoted to the use of inexpensive microprocessors in custom applications

Microprocessor Applications for the 1980's... Its a Whole New Ballgame!

THE MICROPROCESSOR (central processing Clearly, using microprocessors in the 1980's will unit or CPU), a powerful and versatile inte- be a whole new ballgame for electronics enthusiasts. grated circuit, was born only in the last decade. To be certain that readers of POPULAR ELECTRONICS will We have witnessed its startling price decline and be able to keep upAwith what we plan to present to reveled in the result-modestly priced computers. you as time unfolds, we're launching this first -in -a - With $10 microprocessors mailable now, it's clear series microprocessor training course for the new that the devices can be used economically for non - decade. computer purposes-electronic games, telephone dialers, photographic timers, robots, "snart" thermo- What is a Microprocessor? In its simplest terms, a stats, sophisticated security systems, or wher- microprocessor IC can be considered an ele- ever your.imagination leads you. And you ti, ment that can read data from inputs, per- need not tie up a $1000 computer for }'u form computations, and control out- _ I these applications. All that ` is puts. What makes it special is required is a reasonable knowl- that it can be programmed. That edge of microprocessors, i is, it can be made to perform which will also give you a its various functions in any better understanding of - desired sequence. This computer hardware and flexibility is the key charac- software. teristic that lets a micropro- To use a microproces- cessor and external circuit- sor for any of a host of ry perform such a wide vari- applications, you need only ety of electronic tasks. become familiar with: A microprocessor -based The way the processor system is shown in Fig. 1. Note functions and relates to its that there are four main ele- inputs and outputs. ments. These elements can- be The processor's program language. included in the microprocessor IC, but The fundamentals of the binary number for the sake of simplicity we will assume system. that they are all separate components. We will The foregoing doesn't require much more effort deal with the microprocessor itself separately. than learning about 100 words or so of a foreign The microprocessor is connected to all of the language and some simple grammar. Mastering this, other components via the data bus by which informa- you can use inexpensive microprocessors where dis- tion is passed back and forth. Control signals from crete parts would be awkward at best and often the microprocessor along with the memory address prohibitively costly and bulky. signals determine which elements communicate with

AmericanRadioHistory.Com Microprocessor Applications . .

the processor at any one time. understanding of binary numbers and sequence of these lamps to light at any The block labelled Program is the ' their =decimal and hexadecimal (base one time, we must remember 'that the storage area for the sequential instruc- 16) equivalents. lamp will go on only when there is a logic tions to be executed by In the micropró- an 8 -bit microprocessor, the data 1 appearing on the data line at the out- cessor. On reset or power on, the micro,- bus will consist of 8 lines. The status of pút port. It will be helpful to remember - processor will automatically obtain the each of these lines can either be a logic that binary digit, 0 or 1, is referred to as .first instruction from 1 this memory via the or a logic 0, each represented by one a bit. This group of eight bits ís called a data, bus. After executing the first of a pair of vdltage levels (high and low, byte. A 16 -bit address is thus made up instruction ,it will signal for the next positive and negative, etc.). If the micro- of two bytes. Four bits (half ,a byte) are instruction; To etc. generate,this series processor ís reading from the data btñs, '.sometimesr referred to as a nibble. of instructions, better known as the pro-' and lines 0, 1, 2, and 3 are logic 1, and gram, is called "programming." lines 4, 5, 6, and 7 are at logic 0, you can The RCA 1802. In, this article we will The input port section is the communi- write that input as 00001111- as shown. discuss the RCA 1802. In subsequent cation link between the microprocessor articles, other processors will be de- ' and data from keyboards, sensor scribed. Although microprocessors vary switches, or the like. An input port usual- 7 6 5 4 3 2 I 0 DATA BUS LIN i NUMBER `greatly in terms of their capabilities and ly can signal the microprocessor viá the 0 0 0 0 LOGIC VALUE specific language or instruction set, they control bus when data is available. Out, OF EACH LINE are similar in many functions. Some are put ports are used to transfer data from faster, more input/output compatible, the microprocessor or memory compo- Writing long lists of these inputs in easier to program, or more suitable for ' nents to output devices. binary form would be very tedious and data processing, ' etc. But if you can As an example, let's consider this cumbersome. It is convenient to convert understand the basic workings of the system to be the controller for a simple this binary representation of the 8 bits 1802 and its instruction set, evaluating robot and follow some theoretical steps into a hexidecimal form. Thus, 00001111 any microprocessor specification sheet which might occur in its operation. On can be represented by OF (hex). Writing will be easier. (The complete 1802 reset or power, on, the processor will - a 16 -bit address in binary will convince specification sheet 'and instruction sum- signal the program memory to put the you of the value of binary to hexidecimal mary'can be had at no charge by send- first instruction on the 'data bus. Thé conversion. This conversion is listed in ing a self-addressed, processor stamped (30C) reads' and executes that Table I. envelope to Netronics R & D Limited, - instruction. Let's assume that the in: We cannot, however, completely for- 333 Litchfield Road, New Milford, CT struction tells the microprocessor to get about binary representation of these 06776) read the contents of the' input port end numbers because in'that form they wilI As bur first example does not require store that data ín one of its internal reg: 'allow easy identification of which switch all the elements of this processor, we isters. The processor now requests the is to be turned on for a given input or 'will omit those that will not be used: The next instruction, which could be to have ,processor elements we will need are: the microprocessor test the data from SCRATCH -PAD REGISTERS: There the input port. Subsequent instructions, are 16 scratch-pad,registers, each of called on the basis of the data analysis, TABLE I-DECIMAL which holds 16 bits. -They are used to would have the microprocessor issue to -BINARY-HEXADECIMAL hold intermediate results. As the data the output port data that, would cause. EQUIVALENTS Decimal Binary Hexadeci- bus' can handle only 8 bits at a time, the robot to. take a specific action. mal these registers are loaded and unloaded - While the robot is performing its mis- 0 0000 0 8 -bits at a time-the high -order byte in sion, -the processor will request its next 1 0001 1 one operation, the low -order byte in instruction, which might be to reread the 2 0010 2 3 0011 3 another. input port that monitors the progress 'of 4 0100 4 D -REGISTER: The D or Data register the robot. Each reading of the input port 5 0101 5 is used as an input and output to the would similarly be tested, with the micro- 6 0110 6 ALU register (Arithmetic Logic 'Unit). processor issuing commands to control 7 0111 7 Data 'is 'transferred to' the b register, the course of action. This general sys- 8 1000 8 9 1001 9 tested or, modified by the ALU register tem could just as easily operate las a 10 1010 A and then returned to the data_ bus. The telephone dialer or other product. 11 1011 B - DF register -is a flag used in arithmetic 12 1100 C 13 operations to determine if a carry or Signal Lines. Before we tackle the 1101 D 14 1110 E borrow occurred. microprocessor functions, let's review 15 1111 F O: This is a single -bit output line the types of signals you find might on the which can be set orreset by a program signal lines. These lines carry voltages instruction. It is often used as an output. that represent binary numbers. The For example, it can turn a light on or microprocessor, the I/O ports, and :' which light or motor will go on as a result off_. . memory also respond only to these elec- of particular outputs. For example, if we INPUT FLAGS: The 1802 has. four trically coded binary numbers. It would are at an output port capable of driving input flags that are tested for their logic be a great asset, therefore, -to have an low -voltage lamps'and-we want a certain level by instructions. 42 POPULAR ELECTRONICS

AmericanRadioHistory.Com Figure 2 shows a practical hook-up of over processor operations- is required. the memory location specified by the an 1802 microprocessor and a simple We will use=three of the 10 instructions byte (__) following the 30 op code. array of peripheral equipment. Control in this subset. For each, we give the B1 -34__ -Short Branch if EF1=1. If inputs EF1,2,3, and 4 sense when any of mnemonic, gp code, name, and descrip- the EF1 line has a logic value of 1,'the the four pushbuttons is closed. The O - tion. program will branch to the memory loca- output is coupled to transistor Q 1 that, in NOP-C4-No Operation. This instruction that follows the op code. If EF1 is turn, drives a solenoid. Instructions, ' tion performs no processor operations. It not T, the processor 'goes to thea next called for from ROM via the 8 -line causes the processor to remain idle for instruction in sequence. address bus, are delivered via the 8 -line" three machine cycles, then fetch, the 62-35__, 133-36_1_ and B4-37_:__ EF2, data bus. This arrangement is sufficient. " next instruction. It is used mainly in tim- perform the same action ..on the to solve our example problem. ing applications -to generate a delay. EF3 and EF4 lines respectively. REQ-7A-Reset Q. This instruction BNZ-3A__-Short Branch if D not 0. If line contains other than zero, The Problem. For our example appli- causes the processor's Q= to the D register ;assume a low state (0 volt). the program will branch to -the specified cation, we have selected a solenoid - If it contains zero, thé operated lock that will -open only when SEQ-7B-Set Q? This instruction memory location. high advances to 'the next instruc-, four pushbutton switches aré 'operated causes-:the=Q line to assume the program volts). tion in sequence. in'the proper sequence: If any..button is state (+5 Normally, a BN1-3C__Short Brach if EF1=0. If pressed out cf sequence, the controller Branch= Instructions: instructions in the !- the EF1 'input line is a logic zero, the ignores all inputs for a period of one processor executes minute. After that time, it will respond only to the entire combination in correct "sequence. To further forestall attempts to solve the combination, each button SYSTEM CONTROL AND SYNCHRONIZATION BUS must be released before the system will register that the next one has been pushed. Finally, when the lock doe's ADDRESS BUS open, it will ,remain in that condition for only five seconds. i ;:Fy

The Instruction Set: The 91 instruc- PROGRAM s INPUT OUTPUT the 1802 fall into MICROPROCESSOR tions recognized by MEMORY PORT PORT nine categories. In this introductory article, however; we 'will need only four. These are the" Control, Short Branch, Memory Reference and Register Opera- i tions subsets. Each instruction has two DATA BUS 1 identifications-one called a mnemonic (memory aid for .humans), the other FROM EXTERNAL INPUTS TO EXTERNAL DEVICES (SWITCHES, KEYBOARD, (RELAYS, SOLENOIDS, represen- ETC.) LAMPS, MOTORS, called an op code (the digital PRINTERS, ETC.) tation required by the processor). The 1. oprocessor-based system. mnemonic is closely allied to the speci- Fig. Block diagram of a mice fied instruction, and in many cases is an abbreviation. This is exemplified by BR, for BRanch and R7=Q for RESET Q. order in which they are stored in memo- program will 'branch" to., -the specified The mnemonic 'REQ corresponds -go ry-the one at the lowest -order memory memory location. If the EF1 line is 1, the the binary op code 0111 1010, which location first, ( then the next, etc. A program proceeds to thé next instruc- can, for convenience, be .written 7A branch causes the processor to depart tion in sequence. (hex). Eight -bit binary numbers are often from the sequence-, jump to another part BN2-3D_ _, BN3-3E_ -, ' and BN4- written as two groups of four (nibbles). of the memory, and execute one or more 3F_ _ are used similarly to test the Each nibble can be converted into a of the instructions stored there. EF2, EF3 and EF4 lines, respectively. single hex digit. Binary numbers are the Branches are .often (but not neces- Memory Reference. These instruc- only ones the processor"understands." sarily) conditional, taking place only tions allow the user to load data into the Instructions and binary data written in When a defined condition arises. They temporary storage registers in the prof binary form or the hex equivalent are require two bytes of data. The first is -the cessor. We use ,only one of the seven said to be in "machine language:" Data op code for the 'branch instruction and provided. ' is sometimes entered into a processor the second is the address to which the LDI-F8_-Load Immediate. This in- via a hex keypad that automatically pro- processor will branch. For reasons of its struction places the "_ _" data, follow- duces a binary output. own internal organization, the 1802 has ing the F8 op code, into thé'D register of Control Instructions. As the cate- "long" and "short" branch instructions. the processor. If.the instruction were F8 gory name implies,, these instructions We will use 10'oí ghe short ones. 55, the processor 'would place '55 are 'used where some ,general control BR -30_ _-Short Branch. Branch to (010101,01) in the -D register. 43 "MAY 1980

AmericanRadioHistory.Com Microprocessor Applications . . .

Register Operations. These in Fig. 3, begin by writing the word START answer is. NO, this' means that no structions allow operations to be per-, in the center at the top of the page. switches were operated, so the flow formed on the data in any bf 'the <16 Since this will also be a label and goes back,to'the start of the 1st Test. temporary storage registers of the referred to in the program, write this As long as no switches are touched, 1802. These instructions are formed word on the same line in the LABEL the flow "loops" 'around the 1st Test from a hex digit followed by a number to column. Referring to the hardware dia- element, waiting for some switch activi- identify the register. We will, use four of gram in Fig. 2, we can see that when the ty. If switch 3 ' was depressed, the the available seven instructions. flow starts, we want the solenoid to be answer to the second decision box is PLO -AN -Put Low Reg N. Placed the de -activated to keep the. door locked. YES, forcing the flow to proceed to the data byte currently in the D register into Since this occurs when the Q line is low, '1st Release that checks whether switch the low -order register 'specified by N. write RESET 0=0 in a small box directly 3 has been released (opened). If .switch PHI-BN-Put High Reg N. Places the under START. A line, signifying flow 3 has not been released, the flow data byte currently in the D register into direction, joins the' two boxes. The four "loops" around, this decision box until the high -order register specified by Nx Pushbutton switches rTiust be operated switch 3 is released. The next nine decision boxes, down

+ 5V to 4th Release, ask similar questions of switches 4, 2 and 1. (the correct PULL-UP 47K 47K 47K 7K RESISTORS sequence). ' If during these queries, a 256a8 EFI wrong switch is- depressed, the YES EF2 answer'to the decision sends the flow to EF3 the 1 -minute delay and back to the EF4 START..Note that in the flowchart, each pair of switch operatioñ NORMALLY decisions form a OPEN labelled Test, and each i"s PUSHBUTTON Release suit- SWITCHES ably identlied. Once the four pushbutton's have been properly depressed and released, we want the solenoid activated so that the Fiy.2. +5V Example of SOLENOID door will be unlocked. Since the sole- how an 1802 noid -is activated when microprocessor OI the Q line is high, the could be hooked next block (labelled UNLOCK) is up in a simple entitled SET Q= 1. When the Q line control system. goes high in response to this block, two simultaneous events should occur: the solenoid is activated, and a five -second DEC;2N=Decrement Reg N.'. Decre- in a 3-4-2-1 sequence, and if°any switch delay is invoked. At the=conclusion óf ment (reduce by 1) -the digital value is depressed out of sequence, a one - the five -second period, the flow returns stored in the register specified by N. minute time delay will be invoked, after to START and de -activates the solenoid. GHI-9N-Get High Rég N. Places the which the flow will proceed directly back It now scans the 1st. Test, awaiting fur- data ,currently in the high -order register to the START. We have also decided ther switch action. designatéd by N into the D register. that after the correct pushbutton sequence has been entered, the solenoid Creating the Program. The program Programming. - The we example will will be 'activated for only five seconds. that enables the 1802 to, implement the use was previously described. At However, this point, some decisions. regard- flowchart .is shown in Table II. ,The that description is in ing human,'terms that switch condition must be made. A extreme left 'column, marked' 'LABEL, make no sense to the processor. There -- decision box is diamond -shaped with .defines the various parts of the program fore the problem has to be restated in the .flow entering the upper corner and corresponding to the flowchart. They are language that the processor can 'de -r" either of the three remaining corners very useful because the various branch code. The restatement will constitute a used for the YES or NO answers. The addresses are usually filled in' after the program. first decision, labelled "1st Test," deter- program has been structured. In the sec- To create a program, it is convenient mines if any of the wrong switches (1,=2 ond column, identified ás PROGRAM AD- to start with a diagram or flowchart that or'4) has been closed. If the answer is DRESS, are the memory addresses where covers all the steps that 'need be taken ,YES, .the flow then proceeds to the oné- each element óf the program will reside. by the -processor fulfill to the task. The minute delay. At the conclusion of the These too can be filled in' after the pro= analysis of the task is necessarily very delay period, the )low returns back to gram has been written. The reason for detailed, because any step .dmitted or the START, keeping the solenoid de- this is a that particular line in the pro- ' misstated, no matter how minor, can. activated. If the answer is NO (neither grammay consist of two or more bytes, cause the program' to malfunction. switch 1, 2 or 4 has been operated), the and each byte must have an address. next decision determine§ if switch 3 (the Programming convention is. that the pro- Creating the Flowchart. As in shown correct one) has been depressed. If the gram address shown in this column. is 44 POPULAR ELECTRONICS

AmericanRadioHistory.Com Start Computing For Just $129.95 With An 8085 -Based Professional Computer Kit- By Netronics 41:10 , Explorer/85 By Netronics 100% compatible with all 8080A and ASCII/BAUDOT, 8085 software & development tools! registers...single step with register display at each break point No matter what your future computing plans may ...go to execution address. Level "A" in the Hex Version STAND ALONE a applications and can be, Level "A "-at $129.95 -is your starting point. makes perfect controller for industrial be programmed using the Netronics Hex Keypad/Display. Starting at just $129.95 for a Level "A" operating system, 149LELYOMPTE you can now build the exact computer you want. Explorer/85 .. Hex Keypad/Display - ON .. . can be your beginner's system, OEM controller, or IBM - Specifications Computer formatted 8" disk small business system... yet you're never Calculator type keypad with 24 95 forced to spend a penny for a component or feature you don't system defined and 16 user want and you can expand in small, affordable steps! defined keys. 6 digit calculator level a Now, for just $129.95, you can own the first of fully , - type display which displays full Terminal expandable computer with professional capabilities -a com- address plus data as well as Terminal Kit is a puter which features the advanced Intel 8085 cpu, thereby Hex Keypad/Display. register and status information. The Netronics ASCII/BAUDOT Computer giving you immediate access to all software and development microprocessor -controlled, stand alone keyboard/terminal Level "B" Specifications It allows the use tools that exist for both the 8085 and its 8080A predecessor requiring uo computer memory or software. of provides the S-100 signals plus buffers/drivers to a 16 (they are 100% software compatible/ -a computer which Level"B" either 64. or 32 character by line professional display for- up to six 5-100 bus boards and includes: address features onboard S-100 bus expansion -plus instant conver- support mat with selectable baud rate, RS232 -C or 20 ma. output, full decoding for onboard 4k RAM expansion se'ect-able in 75 video sion to mass storage disk memory with either 5.1/4" diskettes cursor control and ohm composite output. 4k address decoding for onboard 8k EPROM expan- or standard IBM -formatted 8" disks. blocks... The keyboard follows the standard typewriter configuration sion selectable in 8k blocks... address and data bus drivers for the 128 ASCII upper/lower case For just $129.95 (plus the cost of a power supply, keyboard/ and generates entire character expansion... wait state generator (jumper selectable), terminal and RF modulator, if you don't have them already), onboard set with 96 printable characters. Features include onboard to allow the use of slower memories...two separate 5 volt lock key, alpha lock jumper, Explorer/85 lets you begin computing on a significant level... regulators, selectable parity, shift regulators. to mate applying the principles discussed in leading computer maga- a drive capability of one TTY load, and the ability Ex- zines...developing "state of the art" computer solutions for Level "C" Specifications directly with almost any computer, including the new both the industrial and leisure environment. Level "C" expands Explorer's plorer/85 and ELF products by Netronics. 4.gro. -. The Computer Terminal requires no I/O napping and Level "A" Specifications motherboard with a card cage, allowing you to plug up to six includes Ik of memory, character generator, 2 key rollover, Explorer/85's Level "A" system features the advanced Intel S-100 cards directly into the processor controlled cursor control, parallel ASCII/BAUDOT 8085 cpu, an 8355 ROM with 2k deluxe monitor/operating video processing motherboard. Both cage and to serial conversion and serial to -fully system, and an 8155 ROM -1/0 -all on a single motherboard accuracy. PC boards are the Explorer/85 ,with I cl cards are neatly contained inside crystal controlled for superb with room for RAM/ROM/PROM/EPROM and S-100 ex- and "C"card cage. Explorer's deluxe steel cabinet. highest quality glass epoxy for the ultimate in reliability pansion, plus generous prototyping space. long life. Level "C" includes a sheet metal superstructure, a 5 -card gold (Level "A" makes a perfect OEM controller for industrial plated S-100 extension PC board which plugs into the mother- applications and is available in a special Hex Version which VIIDEO DISPLAY SPECIFICATIONS number S-100 connectors can be programmed using board. Just add required of The heart of the Netronics Computer Terminal is the micro- the Netronics Hex Keypad/ Level "D" Specifications processor-controlled Netronics Video Display Board (VID) Mk Display.) Level "D" provides 4k or RAM, power supply regulation, which allows the terminal to utilize either a parallel ASCII or PC Board: glass epoxy, plated filtering decoupling components and sockets to expand your BAUDOT signal source. The VID converts the parallel data to through holes with solder mask Explorer/85 memory to 4k (plus the original 256 bytes located serial data which is then formatted to either RS232 -C or 20 ma. I/O: provisions for 25 -pin in the 8155A). The static RAM can be located anywhere from current loop output, which can be connected to the serial I/O (DB25) connector for terminal 0000 to EFFF in 4k blocks. on your computer or other interface, i.e., Modem. a the computer must echo the Level "A" at $129.95 is a serial I/O, which can also sup - Level "E" Specifications When connected to computer, complete operating system, port a paper tape reader character received. This data is received by the VID which Level "E" adds sockets for 8k of EPROM to use the popular perfect beginners, hob- ...provision for 24 -pin DIP processes the information, converting to data to video suitable for Intel 2716 or the TI 2516. It includes all sockets, power supply or industrial con- socket for hex keyboard/dis- to be displayed on a TV set (using an RF modulator) or on a biests, regulator, heat sink, filtering and decoupling components. troller use. play... cassette tape recorder in- video monitor. The VID generates the cursor, horizontal and also be used for soon to be available RAM IC's put...cassette tape recorder output ...cassette tape control Sockets may vertical sync pulses and performs the housekeeping relative to 12k RAM). output. -.speaker output... LED output indicator on SOD (allowing for up to of onboard which character and where it is to be displayed on the screen. (serial output) line...printer interface (less drivers)... total of Order A Coordinated Video Output: 1.5 PIP into 75 ohm (E/A RS-1 70/ Baud Rate: four 8 -bit plus one 6 -bit I/O ports Crystal Frequency: 6.144 Explorer/85 Applications Pak! 110 and 300 ASCII Outputs: RS232 -C or 20 ma. current loop MHz Control Switches: reset and user (RST 7.5) Experimenter's Pak (SAVE 512.50) -Buy Level "A" and Hex ASCII Character, Set: 128 printable characters- interrupt...additional provisions for RST 5.5, 6.5 and TRAP Keypad/Display for $199.90 and get FREE Intel 8085 user's interrupts onboard Counter/Timer: programmable, 14 -bit manual plus FREE postage & handling! ,23021-÷- RAM: 256 bytes located at F800, ideal for 015(8044110090 11~- binary System Student Pak (SAVE S24.45) -Buy Level "A," ASCII Key- isolated stack area in smaller systems and for use as an board/Computer Terminal, and Power Supply for5319.85 and RAM expandable to 64k via S-100 bus or ! is+, -./0123456789;;<=>? expanded systems... get FREE RF Modulator plus FREE Intel 8085 user's manual 4K on motherboard. plus FREE postage & handling! System Monitor (Terminal Version): 2k bytes of deluxe fCVEFCf1I3KLM10P9PSTUJYi(YZ[\l"_ Engineering Pak (SAVE $41.001 Levels system monitor ROM located at F000 leaving 0000 free for user -Buy "A," "B," "C," "D," and "E" with Power Supply, ASCII Keyboard/ RAM/ROM. Features include tape load with labeling ...tape .`abcdefghiiklnnópgrstuwxig{;}"i dump with labeling...examine/change contents of memory Computer Terminal, and six S -I00 Bus Connectors for $514.75 10 B AUDOT Character Set: A L M/VOPQ ...insert data ...warm start ...examine and change all and get FREE computer grade cassette tapes plus FREE BCDEFGHIJK manual plus registers...single step with register display at each break point, 8085 user's FREE postage & handling! RSTUVWX YZ-?: 3$#Q)., 9014!57; 2/68 Cursor Modes: Hone, Backspace, Horizontal Tab, Line Feed, a debugging/training feature...go to execution address... Business Pak (SAVE 589.95) -Buy Explorer/85 Levels "A," Vertical 'Tab, Carriage Return. Two special cursor sequences move blocks of memory from one location to another...fill "B," and "C" (with cabinet), Power Supply, ASCII Key- are provided for absolute and relative X-Y cursor addressing blocks of memory with a constant ...display blocks of memory board/Computer Terminal (with cabinet), 16k RAM, 12" Video Cursor Control: Erase, End of Line, Erase of Screen, Form ..automatic baud rate selection.. - variable display line length Monitor, North Star 5-1/4" Disk Drive (includes North Feed, Delete Monitor Operation: 50 or 60Hz (jumper control (1-255 characters/line)...channelized I/O monitor Star BASIC) with power supply and cabinet, all for just selectable. routine with 8 -bit parallel output for high speed printer... $1599.40 and get 10 FREE 5-1/4" minidiskettes ($49.95 value) , serial console in and console out channel so that monitor can plus FREE 8085 user's manual plus FREE postage & handling! Continental U.S.A. Credit Card Buyers Outside Connecticut with ports. communicate I/O Continental U.S.A. Credit Card Buyers Outside Connecticut System Monitor (11ex Version): Tape load with labeling... CALL TOLL FREE 800-243-7428 tape dump with labeling...examine/change contents of mem- CALL TOLL FREE 800-243-7428 To Order From Connecticut Or For Technical ory...insert data... warm start ...examine and change all (203) To Order From Connecticut Or For Technical r Assistance, Etc. Call 354-9375 1 pmmatom aml a>_ tatter ram tats" EMI - aa tam t= Netronics R&D PE- Assistance, Etc. Call (203) 354-9375 Netronics R&D Ltd., Dept. PE -5 Ltd., De pt. -5 333 Litchfield Road. New Milford, 06776 sonalized disk operating system -just1 333 Litchfield Road, New Milford, CT 06776 Please send the items checked below- plus $2 p&It. plug it in and you're up and running!), Please send the items checked below- Explorer/85 Level "A" Kit (ASCII Deluxe Steel Cabinet for ASCII $699.95 plus $5 p&h. Netronics Stand Alone ASCII Keyboard/Computer Version), $129.95 plus $3 p&h. Keyboard/Terminal, $19.95 plus $2.50 Power Supply Kit for North Star' Terminal Kit, $149.95 plus $3.00 postage & handling. plus $2 p&h. Explorer/85 Level "A" Kit (Hex p&h. Disk Drive, $39.95 Deluxe Steel Cabinet for Netronics Keyboard/Termi- Version), $129.95 plus $3 p&h. Power Supply Kit (± 8V % 5 amps) O Deluxe Case for North Star Disk' nal In Blue/Black Finish, $19.95 plus $2.50 postage 8k Microsoft BASIC on cassette in deluxe steel cabinet, 539.95 plus $2 Drive, $39.95 plus $2 p&h. and handling. tape, $64.95 postpaid. p&h. O Experimenter's Pak (see above)] Video Display Board Kit alone (less keyboard), $89.95 8k Microsoft BASIC in ROM Kit Gold Plated S-100 Bus Connectors, $199.90 postpaid. plus $3 postage & handling. (requires Levels "B," "D," and "E"), $4.85 each, postpaid. Student Pak (see above), $319.851 I2" Video Monitor (10 MHz bandwidth) fully assem- $99.95 plus $2 p&h. O RF Modulator Kit (allows you to postpaid. bled and tested, $139.95 plus $5 postage and handling. , Level "B" (S-100) Kit, .549.95 plus use your TV set as a monitor), $8.95 Engineering Pak (see above), RF Modulator Kit (to use your TV set for a monitor), $2 p&h. postpaid. 5514.75 postpaid. $8.95 postpaid. Level 6 "C" (S-100 -card expander) 16k RAM Kit (S-100 Board expands Business Pak (see above), $1599.401 5 amp Power Supply Kit In Deluxe Steel Cabinet Kit, 539.95 plus $2 p&h. to 64k), $199.95 plus $2 p&h. postpaid. (±3VDC @ 5 amps, plus 6-8 VAC), $39.95 plus $2 Level "D" (4k RAM) Kit, $69.95 32k RAM Kit, $329.95 plus $2 postage & handling. p&h. Total Enclosed 5 1 plus 52 p&h. 48K RAM Kit, $459.95 plus $2 p&h. (Conn. res. add sales tax) By Total Enclosed (Conn. res. add sales tax) $ Level "E" (EPROM/ROM) Kit, - 64k RAM KIt,.$589.95 plus $2 p&h. 0 Personal Check M.O./Cashier's' By - $5.95 plus 50c p&h. 16k RAM Expansion Kit (to expand Check O Visa Master Charge Personal Check Cashiers Check/Money Order Deluxe Steel Cabinet for Explorer/ any of the above up to 64k), 5139.95 (Bank Visa Master Charge(Bankp ----) 85, $49.95 plus $3 x----) p&h. plus $2 p&h each. Acct. p ASCII Keyboard/Computer Ter- Intel 8085 cpu User's Manual, $7.50 Acct 8 1 minal Kit (features a full 128 character Fxp postpaid. Signature Exp Date Signature Date set, upper & lower case, full cursor con- Special Computer Grade Cassette trol, 75 ohm video output convertible Print Print Tapes, $1.90 each or 3 for $5, postpaid. to baudot output, selectable baud rate, Name Name RS232 -C or 20 ma. I/O, 32 or 64 char- 12" Video Monitor (10 MHz bandwidth), acter by 16 line formats, and can be $139.95 plus 55 p&h. Address Addre- s used with either a CRT monitor or a TV O North Star Double Density. Floppy 1 set (if you have an RF modulator), Disk Kit (One Drive) for Explorer/ City City $149.95 plus $2.50 p&h. 85 (includes 3 drive S-100 controller, Hex Keypad/Display Kit, $69.95 DOS, and extended BASIC with per - State Zip State Zip L as Send Me Information a J Dia Send Me More Information MAY 1980 45

AmericanRadioHistory.Com LABEL Microprocessor START START

RESET 0=0 the beginning address of that set of (SOLENOID instructions. DEACTIVATED) The third column,' OP CODE, represents the hexadecimal machine code for the instruction plus any extra byte required I -M NUTE DELAY to modly the instruction. In most cases, the extra byte is a Branch address and is filled in after the program has been completed. The fourth column, MNEMONIC, contains the word -like version d the op code. This column, once you get used to it, makes reading a -program considerably easier. 1ST TEST 4 NO The column marked COMMENTS IS strictly for the human being. At some later date, when you return to the program,reading this column will tell you in NO detail what is supposed to happen at each step. Trying to figure out what the - program does without referring to the comments or the flowchart is difficult. 'When first powered up, the processor fetches its YES first instruction at memory address 0000. The label "Start should use program address 0000. Since we have decided that, at the beginning, the solenoid should be de -activated, we use the mne- 1ST RELEASE monic instruction REQ (reset Q) having the op code of 7A on the start line. The comments column then explains this action and the result. The next step is a decision. In the flowchart, the three wrong switches were tested -in one box. In the program, we` force, the processor to test -each switch in turn for an open or closed condition. Like the flowchart, we label this 1st Test, and use .the next memory address 0001. Switch 1. is tested by the mnemonic B1 having oP- code 34. This 2ND TEST op code checks the -1 NO status of switch (actually the EF line associated with it). It is a two-part op code that requires a brapch address if the switch was

NO depressed. Since we don't know the address of the 1 -minute time delay at this time, we temporarily leave the required second byte, of the op code. blank. Therefore, this line of the op code

column is 34___. . YES Since two bytes were used at address 0001, the next memory 'address is 0003. Here the program op code que; ries the status of switch 2 via op ,code NO IS SWITCH' 4 2ND RELEASE RELEASED? Fig. 3. Flowchart, at left and on opposite page, gives steps YES the microprocessor must perform.

MAY 1980

AmericanRadioHistory.Com Applications . . . YES

35. (B2). Thus program address 0003 3RD TEST contains 35_ _. Keep in mind that, as NO each line is created, sufficient detail must be inserted in the COMMENTS column to explain what is going on. bytes were used as Since two NO address 0003, the next address is 0005. IS questions the SWITCH 2 Here, op code 37 (B4) CLOSED?, status of switch.4. Since this is .still the wrong switch, we must branch to the

1 -minute delay. Thus, address 0005

contains 37_ _. YES Now we are left with, only one switch (switch 3, the correct one). Address 0007 checks this switch via op code 36. If this switch was depressed, the pro- NO

' IS gram branches to the 1st Release, SWITCH 2 3RD RELEASE whose address is as yet unknown. Thus, RELEASED? ¿ address 0007 contains 36_ _. Now, what happens if no switches were- touched? This is the purpose of YES program address 0009. If the flow gets to this' point without, branching, address 0009 forces the program to return to the

1st Test, which we now know' is located YES at program address 0001. Now you see. IS SWITCH the value of the label. Since we are 2,3 OR 4 working with only one page of memory CLOSED? (256 bytes), the leading two zeroes of

the address are not required, "so 4TH TEST

address 0009 contains BR (branch NO immediately) to program address 01. Thus, if during the 1st Test no switches were operated, the program "loops" around this section, awaiting switch NO IS action. SWITCH I Since we have determined that switch CLOSED?1 3' was depressed at address 0007, we now perform the 1st Release at address 000B. The 3E instruction at address 000B says that, if the switch was YES released, branch the program to OF, the start of the 2nd Test. If the switch is still depressed, the instructions at 000D NO force the program to return (30, Branch IS

I, 4TH RELEASE OB, SWITCH Immediate) back to memory address RELEASED?' and await switch release. The 2nd Tést, switch 2 Release, 3rd Test-, switch 3 Release, 4th Test and YES switch 4 Release, operate just as did SET 0= the 1st Test and switch 1 Release. The (SOLENOID UNLOCK reader can follow the program, flow to ACTIVATED) make sure that the four switches must be depressed in proper sequence before the program arrives at the Unlock block at program address 0039. The Unlock statement is one -byte

instruction 7B that causes the 1802 to 5=SECOND set its Q -output line -to the high state. DELAY Since the solenoid is connected to this

- POPULAR ELECTRONICS -

AmericanRadioHistory.Com Microprocessor Applications . . .

output, when this instruction is carried "Idop," which should, total five seconds, 'finds a BR (30) that goes back to -the out by the processor, íthe solenoid .. the contents of the D register will be Start at address 00. At this point, the Q becomes activated and allows the door 0000 0000. When this occurs, the pro- line is forced low and the solenoid is to be opened. - gram moves on to address 0046 and de -activated. The program then pro - As soon as_ the op code at program address 0039 is executed, the -flow TABLE 11-PROGRAM

- passes to the next block having the label 5 -Sec. Delay 'located at program rLABEL PROGRAM OP CODE MNEMONIC COMMENTS address 003A. ADDRESS To create a delay, we can take advantage of the fact that it takes time for the processor to execute an instruc- Start 0000 7A REQ Make Q output low (door locked) tion. Therefore, we can give ít a series of 1st Test 0001 34 48 B1 If switch #1 depressed; branch to 1 - "busy work" -instructions to let it waste min. delay, else next instruction

0003 35 48 B2 If 1 , the, required time. Such maneuvers switch #2 depressed, branch to - should of course produce no other min. delay, else next instruction 0005 37 48 B4 If switch #4 depressed, branch to 1 - external effects. In this case, is data min. delay, else next instruction

passed back and forth between internal 0007 36 OB . 63 If switch #3 depressed, branch to #1 registers- of the 1802' in'. a particular Release, else .next instruction sequence. It is -not really important which 0009 30 01 BR It no switches depressed; branch to 1st Test. registers are used, but the instruction 1st Release 000B 3E OF BN3 If switch released, branch to 2nd set allows us to "play" with the D regis- Test, else next instruction ter more easily íthan with some others. 000D 30 OB BR If switch not released, branch to 1st The delay starts 'at program address Release

2nd Test GOOF 34 48 B1 If switch #1 branch to 1 - 003A by loading FF (1 111 11 11) into the depressed, min. delay, else next instruction D register. The next step uses instruc- 0011 35 48 B2 If switch #2 depressed, branch to 1 - tion Al (address- 003C) to load the FF min, delay, else next instruction

from, the D register into the low -order 0013 36 48 B3 If switch #3 depressed, branch to 1 - half of register -1. Then, according to min. delay, else next instruction 0015 37 19. 64 switch #4 depressed, branch to #2 address 003D, the FF ís also loaded Release, else next instruction into high -order half register -1 using the 0017 30 OF BR No switches depressed, branch to B1 instructioñ. Next, the program con-. 2nd Test tains four NOPs (No Operations), in- 2nd Release 0019 3F 1D BN4 If switch released, branch to 3rd Test, structions during which the processor else next instruction 0018 30 19 BR If switch not released, branch to #2 does absolutely nothing but waste clock Release

cycles. The 1802 uses op C4 ' the code 3rd Test 001D 34 48 B1 If switch #1 depressed, branch to 1 - for NOP, each wastes 1'0-11 microsec- min. delay, else next instruction OO1F 36 48 If onds (using a 1.71 -MHz timing reference' B3 switch #3 depressedbranch to 1 - min. delay, else next oscillator or "clock"). The four instruc- instruction 0021 37 48 B4 If switch #4 depressed, branch to 1 - tions at address 003E "pad" the time min. delay, else next instruction delay so that the loop will come to five 0023 35 27 B2 If switch #2 depressed, branch to #3 seconds. Release, else next instr.uction 0025 30 1D BR If no switches depressed, branch As we now know, register-1 contaiñs to 3rd Test 1 1 1 1 1 1 1 1 (FF). Address 0042 uses op 3rd Release 0027 3D 2B BN2 If switch released, branch to 4th'Test, code 21 to decrement (reduce by one) else next instruction the contents of regiéter-1. After the first 0029 30 27 BR If switch not released, branch 'to #3 cycle low-órder register -1 contains Release 4th Test 002B 35 48 82 If switch #2 .branch 1 - .111'1 1110 (FE). Address 0043 loads depressed, to min. delay, else `next instruction the high -order byte of register -1 into the 002D 36 48 63 If switch #3 depressed, .branch to 1 - D register using instruction 91. We know min. delay, else next instruction 002F 37 48 .that the D register will- contain 1111 B4 If switch #4 depressed, branch to, 1 - min. delay, else next instruction 1 1 1 1 (FF). The 3A instruction at address 0031 34 35 131 If 0044 switch #1 depressed, branch to #4 checks'the contents of the D reg- Release, else next instruction ister. If the.D register is- not all zeros 0033 ,30 2B BR If no switches depressed, branch to (and we know. it isn't), the program 4th Test

4th 1 branches back to address 3E and con- Release 0035 3C 39 BN If switch released, branch to Unlock, else next instruction tinues decrementing the contents of reg- 0037 30 35 BR If switch not released, branch to #4 ister -1, moving the. high -order byte into Release the D register, and checking the contents of the D register for all zeros, etc. After 65,280 passes through the

48 POPULAR ELECTRONICS

AmericanRadioHistory.Com ;xr

ceeds to the 1st Test, ánd loops around gram address 0048. It works by running The 12 -times loop starts at address it, awaiting further switch action. through the 5 -Sec., Delay 12 times under 0048 by loading the D register (F8) with The one -minute delay invoked when a control of another outside loop. This OC (0000 1100) which is decimal 12. wrong switch is depressed starts at pro- action requires,5 X 12 or 60 seconds. Address 004A loads this byte into register -2 (A2). The program from address 004B -to 0056 is the five -second delay as pre- LABEL PROGRAM OP CODE MNEMONIC COMMENTS viously described. In this case, when the ADDRESS D register contains all zeros, the program. drops to address 0057 that decrements the contents of register -2 by one now 1011 or decimal 11). Unlock 0039 7B SEQ Set Q output high (unlock door), go to (it contains next instruction The next two instructions (address 5 -Sec. Delay 003A F8 FF LDI Load FF (1111 1111) into the D regis- 0058 and 0059) are the remainder of the ter "outside" loop that decrements regis- 003C Al PLO Loads D register into low order half of ter -2 each time the five -second delay is register -1 003D B1 PHI Loads D register into high -order half executed. After the twelfth pass, regis- of register -1. ter -2 will contain zero. When this occurs, Timer 003E C4 C4 NOP Waste time to increase delay the program advances to address 005B, 0040 C4 C4 NOP where it is told to branch (30) back to 0042 21 DEC Decrement (reduce) the contents of the Start (00). register -1 by 1 0043 91 GHI Load the high -order byte of register-1 Since we now know the address of

into the D register the 1 -Minute Delay (0048), we can go 0044 3A 3E BNZ If the content of the D register is not back into program and substitute 48 for zero, branch to Timer and continue each of the blanks (depicted ás _ _) dec_rementing register -1 and testing the D register. When the D register that were used where the program had contains zero, go to next instruction. tb branch to the one -minute delay. 0046 30 00 BR End of 5 -sec. time delay, branch to Start. Modifications. The basic program is 1 -Min. Delay 0048 F8 OC LD1 Load the D register with OC (0000 by an inexper- 1100) ,easily modified even 004A A2 PLO Load OC from the D register into the ienced ,programmer. For example, at: low -order half of register-2 each switch Release segment (identi-' D (1111 Loop 1 004B F8 FF LDI Load the register wittiFF fied by its program label), you might as 1111) an exercise write a ,small program that 004D Al PLO Load FF from the D register into the low -order half of register -1 requires, say, that the switch be 004E 81 PHI Load FF from the D register into the released within two seconds, otherwise high -order half of register -1 the program branches to the 1 -minute the delay Timer Start 004F C4 C4 NOP Waste time to pad out time delay. Such a new set of instruc- 0051 C4 C4 tions can reside above program address 0053 21 DEC Decrement the contents of register -1 program) by 1 0050 (the end of the present 0054 91 PHI Load the high -order byte of register-1 and can be invoked (called) from, the into the D register switch release segment. Some branch 0055 3A 4F BNZ If the content of the D register is not statements can be used. If you require a - zero, branch to Timer Start. Continue - the decrementing register -1 and testing longer combination, then enlarge the D register. When the D register program accordingly.. Note that you -can contains zero, next instruction change the combination easily by,mod- register -2 Loop 2 0057 22 DEC Decrement the contents of ifying the pertinent instruction in each, by 1. (Register -2 contains 1100 from address 004A) switch Test location. 0058 82 PLO Load the contents of register -2 into the D register In Conclusion. We have seen how 0059 3A 48 BNZ If the content of the D register is not powerful an, element a microprocessor Loop 1. zero, branch to Continue can *be. To realize even the simple decrementing, then testing the D reg- above in -func- ister. When the D regis'er contains example presented single zero, next instruction tion logic gates would be impractical, 005B 30 00 BR End of 1 -min. delay, branch to Start. Implementing the actions we wanted This sets the Q output low to de- from the microprocessor was a task of activate the solenoid and lock the but modest difficulty by comparison. door. The program then awaits further switch operations. Succeeding articles ín this series will extend the uses of microprocessors further. We will also discuss the hardware needed in riore detail.

49 MAY 1980

AmericanRadioHistory.Com N THEORY, "scratch" and " rumble" tion. This circuit is commonly known as The cutoff (-3-dB) frequency of the filters are useful additions to an audio the Sallen/Key design because it was high- or low-pass filter can be calculated In system. practice, however, the filters described in a paper" by R.P. Sallen and from fc = 1/ [2a(R1R2C1C2)2j. In the built into many components have either El. Key that appeared in the March high-pass filter, of Fig. 1A, the value of - inappropriate cutoff frequencies or too 1955 issue of the IRE Transactions on Cl is chosen to equal that of C2 and the gradual slopes (or both) to adequately Circuit Theory. Shown schematically in resistance of R1 'is chosen to be half perform their intended functions. If Fig. 1, are second order, high-pass (A) that of R2. This simplifies the equation you're dissatisfied with those contained and low-pass (B) active filters employing for the cutoff frequency so that it takes in your preamplifier; integrated amplifier, operational amplifiers. Although. op the form: fc = 1/ 2.828TrC 1R 1. Similarly, or receiver, try the, quartet of high-per- amps as we know them were not avail- in the low-pass filter of Fig. 1B, the formanceactive filters presented here. able in 1955, Sallen and Key's paper is resistance of R1 is chosen to equal that These filters are designed , around a applicable to filters employing more of R2 and the capacitance of C2 is quad BIFET operational amplifier IC, and recently developed active devices. chosen to be half that of Cl. The simpli- can be inserted into or removed from the These filters have unity gain within fied equation for the low-pass cutoff fre- signal chain at the push of a switch. The their passbands, a gain that is indepen- quency is: fc = 1/ 2.8287rR2C2. Note project can be built at low cost, and its dent of resistor values. They have sec- that the low-pass filter resembles the compact size allows ít to be tucked into ond -order responses, which exhibit an high-pass design except that the posi- an existing audio component: Also, its attenuation of 3 dB :at the cutoff frequen- tions of the resistors and capacitors modest power requirements can easily cy, and an ultimate slope of 12 dB/ have been interchanged. be satisfied by the host component. octave. For audio applications, the most If optimal filter performance is to be useful VCVS filter is one whose achieved, the passive components used About the Filters. One of thé simplest response is "maximally flat," whose Q should be of high quality..For example, active filter is based on the designs volt-. is 0.707. This" is° true of the filters the resistors should be carbon- or metal - age -controlled voltage source configura - described .in this article. film components and the capacitors

® ,1 BY JOHN H. ROBERTS A41 9l \

Low-cost - ` 1 l - ultrasonic / c. infrasonic circuit plugs into preamp's external jacks HIGH PERFORMANCE 1 ILVTAI it MUM [LIZ" ., FILTERS --y.

50 I -POPULAR ELECTRONICS

AmericanRadioHistory.Com should have mica, polystyrene or Mylar dielectrics. The criteria for choosing the operational amplifier are those that make an op amp well suited for use as a voltage follower-high input impedance, low input current, and high speed. The author's choice is the Texas Instruments TL074CN, a quad BIFET op amp that satisfies these requirements handily. The complete schematic of the project is shown in Fig. 2. In all, four filters (A) (61 appear in this diagram-a low-pass and a high-pass filter for each stereo chan- Fig. 1. Second -order high-pass (A) and low-pass (B) filters. nel. The component designations not shown in parentheses pertain to the left - ground (which will be tied to system cial and system grounds should be tied channel circuit. Those component num- ground), but the artificial ground gener- together. Direct coupling can be em- bers given parenthetically pertain to the ated by the passive components must ployed between the stage preceeding right -channel filters. be kept isolated from it. The artificial the filters and the project input terminals

If both selector switches (S 1 and S2) ground will be at a dc level equal to one as well as between the project output are in their our positions, the filter out- half of the supply voltage, and the chas- terminals and the input of the next stage puts are left floating. Placing HIGH PASS sis (system) ground will act as the -V in the signal chain. However, if the circuit selector switch Si in its IN position con- negative supply for the quad op amp. is powered by a single -end supply, nects the outputs of the high-pass filters If a bipolar supply is used, the artifi- capacitive coupling should be used. (IC1A, IC1B and their associated components) to the OUT positions of Low PASS selector switch S2 and to the inputs of RI(R2) R5(R6) the low-pass filters (IC IC, IC 1D and 12 (10) 14(8) their associated components). C7(C8) C3(C4) .0019F ; If S2 is in its IN position, signals pass 0022PF through the low-pass filters before they SIA (SIB) HIGH PASS appear at the project's output. Other- OUT IN +V wise, they are routed to the output termi- INPUT L OUT S2A (S2B) (INPUT R) LOW PASS nals without being high-pass filtered. + OUTPUT L ICI .TL074CN CIRCUIT This switching arrangement allows the (OUTPUT R) GROUND VSUPPLY connection of either filter alone, both in CI(C2) ' C5(C6) together, or neither the signal chain. .IPF .lyF The circuit can be powered by either a single -ended supply. Maxi- bipolar or R7(R8) mum voltages are ± 15 volts for a bipo- R3 (R4) lar supply and +30 volts for a single - ended one. Current demand is approximately 10 mA. Components C9, R9, and SEE TEXT FOR RESISTANCE VALUES R10 are required only if a single -ended Fig. 2. Schematic diagram of the complete project. power supply is used. They generate an artificial "circuit ground" which is desig- PARTS LIST nated in Fig. 2 using the conventional Cl ,C2,C5,C6-0. I -µF 5% Mylar; mica or suitable power supply and enclosure, chassis -ground symbol. Contrast this polystyrene hookup wire, shielded cable, circuit Mylar, mica board standoffs, hardware, solder, etc. with the system signal ground appearing C3,C4-0.0022-µF 5% or polystyrene * These components are required only if a at the input and output terminals of the C7,C8-0.001-4F 5% Mylar, mica or single -ended power supply is used. project. An earth -ground symbol sig- polystyrene nifies system signal ground to differen- C9* -0.01-µF Mylar; disc ceramic, mica Note-The following are available from Phoenix Systems, 375 Road, tiate it from the artificial "circuit or polystyrene Springhill ICI -TL074CN quad BIFET op amp Monroe, CT 06468: kit of parts includ- ground." The following are carbon -film, 1/á -watt, ing printed circuit board, IC, switches, A single -ended supply is represented 5% -tolerance . (or metal film, I/4- or and resistors and capacitors for two 20 - to the right of the passive components 1/s -watt, I% tolerance) fixed resistors or 50 -Hz high-pass and two 13.000- or as a battery generating voltage VsuPPLY unless otherwise specified. /9,000-Hz low-pass filters, No. P -9/S text for value. $10.00. Also available separately Traditionally, the chassis on which a RI,R2,R,R6-see for R3,R4-see text for value. are.' TL074CN quad BIFET op amp positive, single -ended power supply is R7,R8-see text for value. IC. No. P -91C, for $2.50:- etched and mounted becomes the negative return R9*,RI0=-2000 ohms, 1/2 -watt, 5% or drilled printed circuit board, No. P- and is also used as the signal ground for 10% tolerance, carbon -composition or 91 B, for $2.00,, push-on/push-off dpdt $1.00 each. the circuit powered by the supply. In the carbon film. switch; No. P-9ISW, for SI,S2-Dpdt switch Connecticut residents, add 7% state case of these active filters powered by Misc.-Printed circuit or "perforated sales tax. If order is less than $10.00, a single -ended supply, the chassis can board, IC socket or Molex Soldercons, add $1.00 shipping and handling. be used as the input and output signal

MAY 1980 51

AmericanRadioHistory.Com Construction. The project is relatively accessible. If the project is placed uate the low -frequency rumble without simple, so point-to-point, wiring, wrap- inside an existing audio component, the significantly altering the spectral power ped -wire, or printed -circuit assembly simplest way to satisfy the project's density of the program material. Most techniques can be used. Etching and modest power requirements is to tap the musical recordings contain little informa- drilling and parts placement guides for a host's supply. A high -voltage supply can tion in the bottom bass octave, so 50 Hz suitable printed circuit board are shown be used to power the project by intro- is an acceptable cutoff frequency. Com- in Fig. 3..If another assembly method is ducing zener voltage regulation. ponent values that will produce a 50 -Hz, chosen, observe sound construction You will note that the values of all of -3 -dB frequency are: Cl, C5, C2, C6- practices for circuits containing high the RC components in the active filters 0.1 µF; R3, R4-22,000 ohms; R7, R8- gain -bandwidth devices. Keep leads have not been specified in the schemat- 47,000 ohms. Those readers who want short and run grounds carefully. ic or the Parts List. This has been done any deep bass present in their record- The use of Molex Soldercons or an IC to allow you to choose the cutoff fre- ings to come through.unattenuated will socket is recommended. Be sure to quencies of the filters that you assem- prefer a lower cutoff frequency. Compo- orient the IC correctly and pay attention ble. The design equations for the low- nent values that will result in a cutoff to polarities when making connections and high-pass filters were given earlier. frequency of 20 Hz are: C 1, C5, C2, to the power supply. Use the minimum In the high-pass design, use equal val- C6-0.1 µF; R3, R4-56,000 ohms; R7, amount of heat and solder consistent ues of capacitance (0.1 µF) for Cl, C5, R8-110,000 ohms. For a cutoff fre- with the formation of good connections. C2, and C6. Select the resistance of R2 quency other than the two just given, The circuit board has been laid out to so that it is double that of R1. The value calculate new resistance values. accommodate pc -mount push/push of R1 can be calculated using the high- Low-pass filters are frequently em- switches. These switches are available pass design equation. In the low-pass ployed to attenuate FM hiss and disc from the source given at the end of the filters, use equal values of resistance for surface noise. They are also useful to Parts List. If you want to employ another R1, R5, R2, and R6. The capacitance of attenuate 19,000 -Hz FM stereo subcar- type of switch, simply interconnect the C7 and C8 should be half that of C3 and riers that can interfere with the taping of foil pads with the appropriate lugs of the C4. Recommended values are 0.0022 broadcasts off the air. To be an effective remotely mounted switches with lengths µF for C3 and C4 and 0.001 µF for C7 hiss or subcarrier filter, the circuit of flexible hookup wire. and C8. Resistance values for any should attenuate high -frequency noise, Mount the filter board either in the desired cutoff frequency can be calcu- etc., without the loss of program content enclosure of a host audio component or lated using the low-pass design data. at lower frequencies. Most musical pro- in an enclosure specially selected for The most common application for the gram material contains little information this purpose. The board should be high-pass filter is to attenuate low -fre- in the extreme highs, so 13,000 Hz is an installed in such a way that board - quency turntable rumble. To be an effec- acceptable cutoff frequency. Compo- mounted switches (if used) are readily tive rumble filter, the circuit should atten- nent values that will produce this response are: R1, R5, R2, R6-8200 -R4 - ohms; C3, C4-0.0022 /IF; C7, C8- 0.001 µF. For a higher cutoff frequency, -R8-- -C6-' -C2- -INPUT R say, 19,000 Hz, use the following com- . -R9- ponent values: R1, R5, R2, R6-5600 +V -05- -R7- -R3- SI ohms; C3, C4-0.0022 /IF; C7, C8- CI HIGH PASS 0.001 µF. If you prefer a cutoff frequency -Ce- ICI other than the two just given, calculate INPUT L -C3- RI new resistance values. -R5- - - OUTPUT L CIRCUIT -RIO- GROUND S2 Installation and Use. The project can L C4 LOW S7 PASS be introduced into the audio system at R6 -R2- OUTPUT R any point where signals are at line level. Two possibilities are at a tape monitor _V loop and between the preamp output and power amplifier input. It's good practice to insert a 51 -ohm resistor between the "hot" output terminal of each channel's circuit and the inner conductor of the cable which carries signals to the input of the next stage.This can prevent oscillation due to the effects of cable or Fig. 3. Full-size etching load capacitance. and drilling guide for printed -circuit board In Conclusion. The active filters pre- is shown at left. sented in this article offer a higher level Diagr4zm for layout of performance than those included in of components is above. many audio components. A bit of experimentation will convince you how useful properly designed low- and high-pass aúdio filters really are.

52 POPULAR ELECTRONICS

AmericanRadioHistory.Com X -10 Wins Microchess Tourney" . "Chess Challenger S -Personal Computing Magazine G``-,.ars E February, 1979 eaX

.' ®,>¡3dí,

.E 14-F tool Ge SpP!fl9 "Its successor, the new Chess Challenger '77 is infinitely more powerful:' -S. Samole President, Fidelity Electronics

Chess Challenger -10 did more than win the total flexibility lets you change games mid- At Level 1, its average response time is 5 Penrod Memorial Microchess Tournament, stream or switch sides with the computer to seconds. At Tournament Level 7, the Chal- it literally trounced all opponents. Personal see how it would handle your dilemna. You lenger makes championship decisions in Computing Magazine, February, 1979, re- can add pieces to your side or take away the just 3 minutes. ports, "Chess Challenger -10 emerged as the computer's Queen. It is a superb teacher! Unbeatable in Price As Well As Play easy victor with ten wins, two draws and no Touch the PV key and the "7's" total recall Best of all, the Chess Challenger "7" is the losses" memory will verify every piece position on most affordable electronic unit you can own. the board. You can even set up hypothetical It is just $89.95 complete with Staunton de- All Top Name Performers encounters to test its reaction at each level. signed pieces and UL approved 110V AC There were no amateurs in the champion- Fidelity's Challenger "7" is able to analyze adaptor. ship playoff. Every contender bore the brand over 3,024,000 board positions. It master- All pieces are magnetized, to stay where of a well-known electronic chess game, and fully handles over one thousand book open- you place them on the permanent metal each was accompanied by its entourage of ings and will respond to any deviation. board. The set is mounted in a simulated coaches, programmers, and engineers. After Academic openings as Sicilian, French, Ruy wood -grained housing which measures each contestant had played all of the oppo- Lopez and Queen Gambit Declined, are just 121/6" x 8" x1'.' Bright, one-half inch tall LED nents in round robin fashion, the brilliant some of the challenges to keep you on your electronic digits, provide unmistakably clear Challenger -10, stood far ahead of its second toes. readout. The unit is backed by a 90 -day place runner-up. manufacturer's limited parts and labor war- It Knows Every Rule in the Book ranty. Nobody Knew The Challenger "7" will permit you to castle Enjoy It for 10 Days-At Our Expense the unde- Unknown to the other companies, or perform an En Passant capture or do so As a gift or for yourself, the "7" is unques- feated tournament leader was being retired itself, if that is its best move. When your tionably the finest chess computer you can Taking its place was a far after the contest. pawn has reached the eighth rank, it will be select...but, if within 10 days, you are not more powerful chess computer, the Chal- automatically raised to a Queen, unless you satisfied, simply return it for a prompt, no - lenger "7': This new micro -computer had tell the computer to promote it to another questions -asked refund. already beaten the official undefeated champ piece. It will take on any player and sharpen during a series of pre -tournament warm-up his skills considerably...but it won't permit games at the factory. Its engineers explain illegal moves. CREDIT CARD ORDERS CALL TOLL FREE that it is simply 14 months ahead in tech- 800-228-5600 nology, in finer sophistication algorithm Sound Signals NE RES: 800-842-8177 and in its superb performance. You just cannot believe the chess I.Q. of this 24 HOURS -7 DAYS/WEEK Improve Your Game to Near Brilliant phenomenal unit. The Challenger "7" has a Within its seven different levels of play, you beep audio feedback which sounds to ac- can enjoy every degree of chess competi- knowledge your move, and double beeps when the computer has made its response. r Please send me Chess Challenger 1 tion, from beginner to tournament skill. Its "7(s)" at $89.95 plus $3.00 for shipping and insurance. Ill. residents add S% sales tax. If Reprinted Personal February. 1979. P. 66. (Darker lines ours.) Results Courtesy of Computing. not satisfied, I can return it within 10 days for a refund. (Final OPPONENTS Enclosed please find check or money order. Charge My Credit Card: CONTESTANTS *1 2 3 6 7 8 9 ,n American Express Master Charge Carte BankAmer./Visa Diners Club Blanche ` ve,oi'oO'''O~ Credit Card No W % 1 0 MICRO -CHESS 1.0 0 0 0 Master Exp. Date l\\\\ 1 3 8 2% Charge 7 ---- (Heath 11.8) B % X 0 0 0 0 Name MICRO-CHESS 1.5. W \X X % 0 0 0 2 0 5 7 2X 6' Address (TRS-80) B X 0 0 0 % 0 City MICRO -CHESS 2.0 W 'A 1 1 0 0 % 3 3 4 5 5 4 State Zip (PET) B 1 X 0 0 0 - %C// Signature 4 CHESS CHALLENGER (3 Level) 2 5 5 4X 5 Camelot 70 B 0 X 0 / \ 0 0 X - a.PE-06 J % 10 11 1 S CHESS CHALLENGER (IOTevel)- 1 --:-I'" 2 0 B 1 1 1 / \ 1 X - W 1 X 1 1 0 1 6 BORIS 7 2 3 8 3 B I 1 1 X 0 0

SARGONI W 1 1 1 X X 1 6 5 1 8% 2 (TRS-80) B 1 1 n '4 X 0

W 8 ATARI Did not play DIRECT B Camelot

Note: Microchess 1.5 wins 6th place over Microchess .0 by virtue of the tie breaking analysis of rol live strength of opponents 801 Green Bay Rd., Lake Bluff, IL 60044 A DIVISION OF UNITED EDUCATORS. INC.

MAY 1980 53

AmericanRadioHistory.Com .- -

1"¢ put more thought into our leader than most manufactur s put into their tape.

One of the reasons Moxell has such a It also points out what side of the tape levels without wasting tape. Or time_ great following is because of our leader. you're on (A or B) os well as which Obviously, all the thought that went into It has a built -.in non-abrasive head direction the tape' is traveling. So it's almost ,our leader was designed to help you get cleaner designed to remove the oxide impossibleto make a mistake. more out of our tape. residue other tapes leave behind, without It even gives you a five second cuei.ng So if you think our leader sounds damaging your tape heads. mark, so you can set your recording impressive, wait till you hear what follows it. imaxeli IIIIIIIII IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII111111111IIIIIIII 11111111111111111111111111111 IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII111!IIII IIIIIIIIIIIIIIIII Moxe o1 CIRCLE Ma 40 OM FREE INFORMATION CARD CaPxonon Anarco, 60OaSod Crrve, Moochm, N A 07074

AmericanRadioHistory.Com HERE IS AN easy -to -build, battery - 31/2 -digit thermometer, BY TOM FOX operated which we call "LIDITH" for Liquid -crystal Digital THermometer. It can measure temperatures from -30° F to +199° F. Basic accuracy is better than ± 1° over its entire range and averages better than ±0.5° from 0° to 100° F. Each degree is divided into 10 equal parts, giving Lidith a 0.1° F resolution. Readout is on a %" BUILD LIDITH' (12.7 -mm) liquid crystal display. With some simple circuit modifications, Lidith can perform other functions, such as reading the temperature in °C, measuring accurately down to -67° F and displaying both indoor and A 3½ -Digit outdoor temperatures. Circuit Operation. Shown in Fig. 1 is the schematic diagram of Lidith. (See Box for details on sensors.) Resistor R11 is the series voltage dropper for the 6.8 -volt tener diode in the temperature transducer (IC2). The R12/C6 network provides additional stability if the trans- Digital ducer is used as a remote sensor. Re- sistors R9 and R10 form a precision voltage divider to insure that the proper proportion of the transducer's output voltage goes to the digital panel meter Thermometer (DPM) circuitry. Measures from -30° to + 199° F with Several points should be noted about the 1C2 circuit. At room temperature 1° accuracy and 0.1° resolution (77° F), the transducer's output from pins 1 and 2 to pin 3 is nominally 2.98 volts and increases by 10 mV for every 1°C or 1.8° F increase in temperature. This potential is measured with respect to +9 volts, not ground. This means that T H LID I at 77° F, pins 1 and 2 are at -2.98 volts, with respect to +9 volts. The heart of the DPM is the Intersil ICL7106 single -chip 31/2 -digit MOS A/D (analog -to -digital) converter that drives the LCD. The 7106 uses dual -slope conversion, in which linearities tend to can- ; Ii11411"::".4Y4r1". " ° ..r cel out. Therefore, the circuit does not require extremely accurate or stable (and expensive) components. Also, as long as it remains unchanged for a sin- LCD gle conversion cycle, the clock frequen- DIGITAL cy does not have to be precise or extremely stable. The only real require- THERMOMETER ment is a stable current reference. In addition to ease of use and relatively low cost, the 7106 has several other { features that make it ideal for use in Li- ir dith. Since the thermometer employs

. CMOS circuitry, it consumes little cur-

a ` 0FF rent (about 0.8 mA). It has true auto - zeroing, will directly drive LCD displays, and has a guaranteed ±1 -count accuracy over its entire ±2000 -count range. The RC network for the 7106's inter -

MAY 1980 55

AmericanRadioHistory.Com EVALUATION KIT (SEE TEXT) 0+9V

r RI R6 .22111( 27j 1 ,22K 12K (SEE DISP I SI r R2 k TEXT) 47K 28 -9V- 81 R12 R9 1 4711 IOK .47pF1 29 30 R5 C5 IM ,OIpF - R7 .IpF ""*"..% 5K M/V,Mh rP,31 33 PINS t3 THRU 18 RIO CI ICI ..19F ?TN AND 22,23,24 DECIMAL 40.56 K 34 7106 POINT TP2 R8 R4 36 62K IK - o 35 PINS 9 THRU 14 TP3 AND PIN 25 o 32 40 39 R3 PINS

IOOK' - 2 THRU 8 38 C4 IOOpF 261 37 21 BACKPLANE

Fig. 1. Most of the components are supplied with the meter evaluation kit as shown within dashed lines. Temperature =400I sensor and other components are connected to kit as shown here. IC3 PARTS LIST

B I -9 -volt battery R7 -5000 -ohm, multi -turn trimmer potenti- CI -0. I -µF capacitor * ometer C2-O.47-1,1.F capacitor * R8-62.000 ohms C3 -0.22-11F capacitor * R9-10,000 ohms, 1% C4-100-pF capacitor * R 10-40.560 ohms, 1%

C5 -0.0I -µF capacitor * R I 1 -2000 -ohm. 5% C6-0. I -µF capacitor R 12-47 ohms, 10% DISPI-3' -digit LCD display * S I-Spst switch ICI -7106 31 -digit A/D converter (Intersil) * Misc.-Battery holder, IC socket (I), three - IC2-LX57(0 temperature sensor (National) conductor flexible cable, 3/16" to '/á' ID IC3-4001 quad 2 -input NOR gate thin -wall brass or copper tubing, spaghetti. Note: The following are available from T. R. The following are 5%,'/4 -watt resistors unless E-PDX-E ribbon, acrylic spray, plastic case Electronics, RR#1, Box 604, Newaygo, otherwise specified: (Radio Shack 270-627). I/8" -thick clear plas- MI 49337: Kit containing one LX5700, R9, R I -22,0(X) ohms tic sheet, black spray paint, glue, mounting and RIO at $9.75 postpaid (ask for #ST2R R2-47,000 ohms * hardware, etc. for conventional kit, #CT2R for Celsius R3-100,000 ohms * * These items are supplied in the Intersil Sin- version, or #AT2R for "Alaskan" ver- R4 -10O0 -ohm trimmer potentiometer * gle Chip Panel Meter Evaluation Kit avail- sion). Also available separately: LX5700 R5-I megohm * able for $29.95 plus $1 shipping and han- temperature sensor (with data sheet) at R6 -12,0(X) ohms dling from Ancrona. Box 2208P. Culver $6.50 plus $0.50 postage and handling; a City, CA 90230. Ancrona also sells the matched pair of LX5700s (±I° C or better) ICL7106 IC for $14.70. at $15.00; R9 and RIO at $1.75 each.

nal oscillator is made up of R3 and C4. and REF LO. In Lidith, R4 is basically a work (and connected to IN LO) when the With the values shown, oscillator fre- scale -adjust trimmer potentiometer. transducer's temperature is at 0°. We quency is about 48 kHz. Capacitor C3 Another adjustable voltage -divider can conclude, then, that R7 can be and resistor R2 are the integrating com- that uses the 7106's 2.8 -volt reference is viewed as a 0° trimmer pot. However, ponents, while Cl is the reference capa- made up of R6, R7, and R8. Notice that since 0° F is not easy to achieve, R7 will citor and C2 is the auto -zero capacitor. temperature -adjust trimmer R7s wiper actually be set for a display of 32.1 when Low-pass RC filter R5/C5 is used for im- is connected through filter resistor R5 to the transducer is immersed in ice water. proved noise rejection. pin 31 (IN HI) of the 7106. As the transducer's temperature rises,

A stable 2.8 -volt reference potential Once the thermometer is calibrated, its output at pins 1 and 2 becomes more between pin 1 (V+) and pin 32 (COM- with R7 at a fixed position, IN HI is at a negative, with respect to +9 volts. This MON) is provided by the 7106. Resistors fixer' voltage. For the DPM to display more -negative potential is felt at the R1 and R4 form an adjustable voltage - 00.0, its IN LO (connected to the trans- 7106's IN LO input. When IN LO be- divider network that applies a suitable ducer's voltage -divider network) must comes more negative, with respect to IN proportion of this reference voltage to be exactly equal to its IN HI point. Thus, HI (which is set at a constant voltage af- pin 36 (REF HI) and pin 35 (REF LO). after calibration, the voltage at R7s wip- ter calibration), the 7106 senses this as Adjustment of R4 is made for a potential er must be identical to that coming from a positive voltage at its input, since IN HI of 0.110 volt (110 mV) between REF HI the transducer's R9/R10 divider net - is now more positive, or less negative,

56 POPULAR ELECTRONICS

AmericanRadioHistory.Com than IN LO. Therefore, the DPM displays a positive number. When the transducer's temperature goes below 0°, IN LO is less negative than IN HI and the DPM indicates a negative temperature. DISPLAY The 7106 directly powers all segments of the LCD. Pin 21 goes to the OMIT JUMPER display's backplane, while the frontplane segments connect to pins 2 through 25, excluding pin 21, which connects to the Fig. 2. The main outline decimal point between the units and here is that of the meter evaluation kit. Thermometer tenths decades in the display. Between C3 ICI components can be added the decimal point and pin 21 is a CMOS to the "open" area on the inverter that provides the proper ac volt- T'2 C4 kit board created by R2 age with an insignificant dc offset. It may .-=- CI taking off the battery. -----, I -O C2 R3 seem wasteful to use an entire 4001 for ,TP3 this trivial task when a single MOS tran- *-1=1- v R7 would do the same job, but a 4001 OMIT j sistor BATTERY I Ñ HOLDER i is less expensive and more readily avail- R4 MOUNT R9 ADD-ON RIC R5 able. HERE RI

Construction. Unless you can obtain R12 r J a suitable 31/2 -digit LCD at reasonable _J cost, we strongly recommend Intersil's PINS PIN °IN OMIT CHANGE ICL7106EV/KIT Single Chip Panel Me- 192 3 4 JACKS TO 22K OF OF OF (SEE TEXT) ter Evaluation Kit. It is available from An- IC2 IC2 IC2 crona Corp. (see Parts List) and other Intersil distributors. If you are set on building your thermometer from scratch

instead, follow Fig. 1 and the pin con- TEMPERATURE SENSOR figuration guide for the LCD you buy. SUPPLIERS Except for the remote sensing transducer, all thermometer components There are a number of manufacturers who able. For every 1° C rise or fall, current in- mount on the Evaluation Kit's circuit produce temperature sensors suitable for creases or decreases by 1 A. Premium use with Lidith. The following,is a list of a model AD590M has a guaranteed max- board. Build the Kit following the instruc- few such manufacturers, followed by brief imum calibration error of ±0.5° C- at 25° C. tions supplied' with it. Then, referring to descriptions of the suitable sensórs. If you prefer to deal with voltages instead Fig. 2, replace R1 supplied with the Kit Precision Monolithics Inc' of simply add a precision resistor (1500 Space currents, with a 22,000 -ohm 5% (or better) toler- Park Dr., Santa Clara, CA 95050) pro- in series with the transducer. -film (If duces Ultra -Matched Monolithic Dual National Semiconductor Corp. (2900 ance carbon or metal resistor. Transistors, Series MAT -01, which, with Semiconductor Dr., Santa Clara, CA you can adjust R4 for 0.115 volt or more suitable amplification, can be used in an 95051) produces the LX5600/5700 series between TP2 and TP3, R1 need not be changed.) Eliminate the battery holder, specified jumper, and banana jacks. Drill holes for and mount the extra circuitry as

shown. Refer back to Fig. 1 and interconnect all on -board components. A 1" to 2" (25.4- to 50.8 -mm) length of 3/16" to r/" (4.8- to 6.4 -mm) inner -diameter thin -walled brass or copper tubing should be used as a heat sink for the transducer if you plan to measure air temperatures. If you plan to use Lidith primarily for taking ,body and liquid tem- electronic thermometer.' For detáils; -con- of IC temperature transducer specified in peratures, you can omit the tubing. Use sult the company's application note' No.. Lidith's Parts List. As shown in the diagram a length of flexible three -conductor ca- AN -12' titled "Temperature Measurement in this box, the transducer includes a built- ble to interconnect transducer and cir- Method Based on Matched Transistor Pair in operational amplifier, internal zener di- cuit The can be up to Requires No Reference." ode to.provide voltage regulation, and out- assembly. cable Analog Devices (Rte. 1, Industrial Park, put transistor whose collector can be re- 50' (15.2 m) long with no problems. P.O. Box 280, Norwood, MA 02062) has turned to a potential as high as 36 volts. Referring to Fig. 3, slip the metal tub- recently released the AD590 Two -Termi- There are undoubtedly other semicon- ing onto the cable as shown. Then re- nal Temperature Transducer. It produces ductor manufacturers who make sensors move about 1" of the cable's outer jacket an output current proportional to the abso- and transducers similar to those men- lute temperature. At room temperature tioned above, and this is not intended to be and prepare the ends of the conductors. (77° For 25° C), a 298.2-µAoutput is avail - a complete list. O Slip a length of plastic tubing over each

MAY 1980 57

AmericanRadioHistory.Com conductor. Using a heat sink between PLASTIC TUBING BRASS OR COPPER TUBING transducer and tie points, solder the conductors of the cable to the leads on the transducer. Then spray several coats of plastic insulation (such as GC's Koloid K-29 or Clear Acrylic Plastic) over the connections and exposed wires. Al- ternatively, dip the entire transducer assembly in GC Liquid Tape. When the coating dries, push the plastic tubing Fig. 3. Temperature probe construction. Make sure all soldered down until it contacts the transducer's connections are well insulated. Thin metal tubing is optional. body and covers all bare wires.

Clean the transducer and metal tubing SOLDER TRANSDUCER TO TUBE with fine steel wool or sandpaper. Refer- ring to Fig. 4, solder the transducer to the tube, taking care to be sparing with the heat. Finally, use epoxy putty to make a waterproof probe out of the transducer assembly. Prepare the putty according to directions and then wet your hands and \PULL TUBE UP AGAINST TRANSDUCER form a rough cylinder around the transducer assembly. Do not be concerned if Fig. 4. Solder the optional heat sink to the heat sensor. Then use epoxy your work appears messy. Just make putty to form a waterproof probe out of the transducer assembly. sure the transducer and connections are completely sealed. With damp hands, forming calibration in a warm room ducer specified is almost perfectly lin- roll the rough cylinder between your where ice water will be melting. In any ear. According to the conservative spe- hands until it is smooth and nearly per- event, what you are really measuring is cifications, the nonlinearity of the fectly cylindrical and has a blunt cone - the temperature of the water, which will LX5700 is less than ±0.5%. The only shaped tip. not be exactly 32° F. If Lidith was cali- possible significant error left, then, is a Mount the thermometer circuit inside brated exactly as described above, slight slope error, the worst case of a housing large enough to accommo- there are only two possible sources of which is about ±0.4 mV/°K. With a labo- date it and its battery. error left-the transducer's slope and ratory thermometer and some patience, linearity errors. Fortunately, the trans- even this error can be removed. Calibration. If possible, the following -P reference -voltage adjustment should be - performed with the aid of a digital multimeter. However, a good -quality analog s,t voltmeter can be used if its input impedance is 1 megohm or greater. If you have a laboratory thermometer, you can do away with the need for a meter altogether, but calibration will take considerably more time. (More about this later.) Turn on the power and let the thermometer warm up for at least 2 minutes. Then, with the meter set to its lowest Photo showing range, connect the negative prod to TP3 back of meter (actually a jumper) and positive prod to evaluation kit TP2. Referring to Fig. 2, carefully adjust board after extra R4 for a reading of 0.110 volt. holes have been To calibrate the thermometer, you will drilled and need a plastic bucket filled about three- components for quarters full with compact clean temperature sensor snow, have been added. ice chips, or ice cubes. Pour in enough cold water to nearly fill the bucket. Place the transducer probe in the center of the ice/water mixture and wait a few minutes until the LCD stabilizes at some number. _ .. Vigorously stir the ice mixture and ad- , ' _'- e just R7 for a display of 32.1. This display ry figure is 'more desirable than the usual 32.0 because you will most likely be per - M : ,

58 POPULAR ELECTRONICS

AmericanRadioHistory.Com +9V OUTDOOR tronic Weather Projects published by

INDOOR Howard W. Sams & Co., or refer to some other suitable book on weather in- s2 Fig. 5. Diagram shows how struments.) TO OUTDOOR REST OF to connect two temperature CIRCUIT If you turn on Lidith only when you INDOOR sensors to the basic wish to know the temperature and leave RIO thermometer. For best results, sensors used the power off at all other times, a standard 9 -volt battery should last more than should be matched. a year. For a continuous display, omit *.MATCHED Si and use six alkaline D cells in series IC2* TRANSDUCERS LX5700 instead of the 9 -volt battery. In continu- (INDOOR) ous use, the D cells should last about a year or more. The thermometer can be used to the In addi- Using Thermometer. measure temperatures in two different tion to the use of obvious measuring locations, such as indoors and outdoors, room and ambient temperature, Lidith is using the circuit shown in Fig. 5. Bear in ideal for measuring temperatures in mind, however, that if you select two pools, for isolating excessively warm LX5700 transducers at random, one of To remove the slope error, adjust R4 electronic components in an operating the temperatures measured can be off and R7 exactly as described above. (If a circuit, as a remote -indicating freezer or by as much as 14° F, due to the possible DMM is not available, initially set R4 to refrigerator thermometer, and as a med- ±8° C maximum offset error of the de- íts midpoint.) Place the probe and lab ical thermometer. (If you calibrate accu- vice. This error can be reduced to 4° C if thermometer in warm (about 120° F) wa- rately for 98.6° F against a good -quality you use premium -quality LX5700As. ter and, while stirring the water, adjust oral mercury thermometer, the accuracy Even so, your best bet would be to use a R4 until Lidith's display indicates exactly of Lidith can approach ±0.1° F over a 92° pair of custom -matched transducers the same temperature as the lab ther- to 110° F range.) The Celsius version (see Parts List). mometer. Then place the probe in a can also be used by auto hobbyists as a With a few changes in component val- bucket of ice/water and adjust R7, if water -temperature monitor. ues, you can make Lidith measure tem- necessary, for a reading of 32.1. Return To accurately measure outside -air peratures in Celsius degrees from -55° the probe to the warm water and, if nec- temperatures, you need both an accu- to +125° C. You can even make an essary, readjust R4. Repeat the immer- rate thermometer like Lidith and a suit- "Alaskan" version that measures down sion -and -adjustment procedure until it is able thermometer shelter. (For details to -67° F and up to +199° F. no longer necessary to trim the settings on measuring outside -air temperature, The following changes are required of the potentiometers. see pages 23 and 25 of Unique Elec- for both the Celsius and Alaskan versions. First, change C2 to a 0.1-µF My - V1i1f1At101ñTLf. ° <,rt. x, 9 for a 00.1 reading on the LCD when the Front view of meter probe is immersed in an ice/water mix- 1M , ture as before. 11 evaluation kit 5 showing components For the Alaskan version, change R6 to km> for temperature 82,000 ohms, R8 to 15,000 ohms, and -sr sensor added in RIO to a 1120 -ohm, 1% tolerance preci- area where sion resistor. Calibrate exactly the same battery holder was. as for the regular version, but adjust R4 for a potential of 0.500 volt between TP2 and TP3.

Summing Up. Lidith is a truly state-of- the-art precision digital thermometer. With a few minor changes, it can be "tailored" to your needs. And, in ordinary use, it is highly energy -efficient, thanks to the use of low -power MOS circuitry and liquid -crystal display. O

MAY 1980 59

AmericanRadioHistory.Com . id In 9 Fo tam...n.. YOUR ULTIMATE AIR FRESHENING/ IONIZING SYSTEM. TOP QUALITY. LOW PRICE. STATE OF THE ART.

Breakthrough. The new Ion Fountain' is which masks or deodorizes. The unit actually absolute best quality and doesn't mind pay- in a class by itself. This negative ion genera- removes the dust, smoke, bacteria and pollen ing a little extra to get it. If you want highest tor gives you power to saturate your home or particles from the air by attaching ions to ion output, flexibility, and a beautiful oak office with billions of refreshing ions. With- them and causing them to sink to the earth paneled case, buy the Executive System out fans or any moving parts it puts out a where they can be vacuumed up rather than Four. pleasant breeze. A pure flow of ions pours inhaled. At the same time ions electrically If you want something at half the price of from the top like water from a fountain, filling stimulate the energy -stripped air. the Exécutive System Four, but still better your room. The result? Your air feels like than any other units costing up to $250, buy YOUR CHOICE fresh ocean air-pure, crisp, and wonder- the Ion Fountain. fully charged. OF TWO TOP-QUALITY UNITS! There's only one unit that's better than HOW TO GET ONE The price? Only $79.95. That's a price the Ion Fountain. That's our own Executive breakthrough because no other company To place your order now just send a System Four'. It sells for $159. It has an check for can offer you a unit with higher ion output or $79.95 plus $3 shipping for the Ion even higher ion output. Plus! Our better quality than the Ion Fountain'", even at special Fountain. Or send $159 plus $4 shipping for Dial -Ion triple our price. -An feature allows you to adjust the the Executive System Four. Tell us your full ion output anywhere from low to high. Not street address as we cannot ship to Post HOW CAN WE DO IT? everyone knows that the need for ions Office boxes. (California residents add 6% Six years of experience helps. Plus a lot varies. A large smoky room will require sales tax.) of ingenuity, aggressive research and a higher output than a small room. And some Our unit is dependable and trouble -free, personal commitment to give our customers people want fewer ions while sleeping than but if by rare chance any problems occur our the best we can. while working. The new Executive System service -by -mail center sends off your unit UTP Ion a Research Center is branch of Four is cur answer to this need for output within 24 hours of receipt or sends a replace- our educational publishing company. And flexibility. ment so you are not without fresh air and can our commitment in publishing to give birth enjoy your dust -free And FACTS YOU NEED TO KNOW environment. each to new ideas and methods that enrich Air Energizer is backed a full The Ion Fountain'-System by one-year humanity is part of the Ion Research Center Five limited warranty. too. We're in business to serve you and your Ion density: 430,000 ions per cm3/sec. environmental needs. at 1 meter. 1.55 million ions HOW TO GET ONE FAST per cm3 at 50 cms. Credit card holders can call our toll -free WHAT ARE IONS? Use.' Large room or office -9000 number below. Order a unit now and if you Ions are electrically charged atoms in the cu. ft. are not satisfied with its effects within 10 air with either a positive or negative charge. 1 Warranty: year days simply return it for a full cash refund. The sun and cosmic rays as well as lightning Output voltage: 15 KV Order your Air Energizer today. and fast-moving water (like waterfalls, surf) Ozone: Less than 2 parts per billion generate trillions of negative ions every day. Dimensions: 53/e" x 41/4" x 23/s" The more negatively ionized the air, the' Executive System Four' fresher and is. more alive it Air pollution, Ion density: Low to maximum of 540,000 Read "The Golden Egg" artificially controlled climates (with air con- ions per cm3 at 1 meter. 1.6 the Trees Press ditioning and heating) and electronic equip- x 106 ions per cm3 at 50 University of ment all produce excess positive ions, depriv- cms. ION RESEARCH CENTER , Dept. PE4 ing the air of these small negative air ions Output voltage: 15 KV Box 644 BOULDER CREEK, CA95006 and creating dead "stuffy" air. Ozone: Less than 2 parts per billion Call Toll -Free ... 800-538-0750 Dimensions: 1 1 " x 5" x WHAT'S THE 4" In California call (408) 338-6663 SOLUTION? Use: Large room or office 10,000 Our rapid which Send check or use your Master Charge, -growth technology, cu. ft sometimes takes its toll on the quality of our Visa or American Express card. Warranty- 1 year air, has also come up with the solution. If the Executive System Four is better, Following Nature's model of the thunder- why did we bring out the Ion Fountain? Not DETECT YOUR IONS storm which uses a high electrical charge to everybody is willing to pay $159 for an air This simple but accurate detector instantly purify, revitalize and stimulate the air, the ionizing unit, no matter how good it is. Just gives you a reading of ion intensity. UTP Air Energizer has been developed imitat- like not everyone drives Rolls Royces. Most The Econometer.... (Pen Size).... $7.50 ing this process. Both the thunderstorm and drive less expensive cars. The Executive [If ordering separately include $2.00 for the Air Energizer fill the air with negative System Four is for the person who wants the shipping] ions, restoring the natural electrical balance to the polluted, energy-depleted air. But the Ion Fountain can be used indoors in the SURVIVAL! Spirulina is a new wonder food supplement higher in protein than any other natural home, office, workshop, laboratory, etc., source. Very high in other nutrients too. Find out how you can be a commissioned representative of the Light Force Family and distribute Spirulina in either or keeping a fresh supply of ionized oxygen bulk as special vitamin supplements. Generous commissions and opportunities available. Phone or write available night and day. This new break- for your free information. (408) 338-9436. Please do not use the toll -free number for information. hrough in fresh air control is not a cover-up

60 POPULAR ELECTRONICS

AmericanRadioHistory.Com 1144_14113, .

s`t .i.q 111,

-.r i

-, a P--

BY WALTER GONTOWSKI, JR.

INTRUSION alarm systems are in- creasingly popular today owing to the growing incidence of crime. A new security system based on an IC motion detector developed by the Sprague Electric Company doesn't have the limi- tations of other types while sharing some of their advantages. Called the Optical Detector Modular alarm system (Opdec), the system presented here may be likened to a many -eyed optical dev ce that detects movements through ligh' changes, but is much lower in cost than an ultrasonic -type alarm and is resistant to false alarms. Cther characteristics of the Opdec include modular construction, provisions for timed exit and entry, and input termi-

MOTION-DETECTOR ALARM

nals for optional closed-loop wiring that Many -Eyed Modular System can yield added protection. Finally, Opdec can also function as a fire/ smoke detector at the same time that it Low -Cost IC is on the lookout for intruders. The Motion Sensor. The heart of the Opdec system is Sprague's ULN-2232A Responds to Light Changes Integrated Optical Motion Detector. Un - MAY 1980 61

AmericanRadioHistory.Com +vcc ee , Vcc.? MODE SELECT

4 BIT CURRENT REGULATOR CLOCK CURRENT. SPEAKER COUNTER -SOURCE CONTROLLED I OSC. DRIVER

ALARM 0LOW-LEVEL LENS GENERATOR GROUND

TIMER LAMP PHOTODIODE DRIVER V J

TRIGGER

LOG CONVERTER VOLTAGE AMPLIFIERS THRESHOLD DETECTOR ONC

HIGH.LEVEL V GROUND -J- _L C2 ,-r\ C3 Fig. 1. Block diagram of the Sprague ULN-2232A Integrated Optical Motion Detector reveals chip's internal structure. TRINPUTIGGER ?sr R +VREG O

R18 RIB 09 11121 R22 0 13 270 75 6.2K R251 R26 A n 10K 4.3K 4.3K

/ RI 4 R17 R20 012 68K 51K 6.2K

012 DII 010

. D9 010 RI5

823 R16 5.IK 470A l C20 TOOBF

SIB EXIT DELAY PERIMETER MONITOR LATCH Fig. 2. Schematic diagram of. the Opdec system's supervisory Signal ...- PERIMETER Processor module has major functional stages labelled. Points des - LOOP WIRING

like a conventional optoelectronic alarm room or moves around in it, the amount fier, a threshold detector and an alarm sensor (usually a CdS photocell) that of light reflected to the sensor IC will generator. Sensor operation is as follows. triggers the alarm when the path vary. The sensor has been designed to The photodiode generates a small between a light source and the sensor is respond to this change in light level. electric current when it is irradiated by interrupted, this novel IC senses the A block diagram of the ULN-2232A IC light energy. This photocurrent is pro- presence of an intruder by detecting sensor is shown in Fig. 1. The chip con- cessed into a voltage by logarithmic in changes the amount of ambient light tains, among other things, a photodiode, converter A 1. Taking the log of the cur- reaching it. As the intruder enters the a logarithmic converter, a voltage ampli- rent allows sensor operation over a 62 POPULAR ELECTRONICS

AmericanRadioHistory.Com PARTS LIST FOR SIGNAL PROCESSOR MODULE (including System Power Supply)

CI 10,000-4F, 25 -volt electrolytic otherwise specified. S I -Dpst switch Cl 7;C20,C2I-1000-µF, 6 -volt electro- RI -100 ohms, 2 watts, 10% tolerance T1 -24 -volt, 2 -ampere center -tapped lytic R13-43 ohms, 4 watts, 10% tolerance transformer (Stancor P-8662 or simi- CI8-0.47-µF, 6 -volt tantalum R 14-68,000 ohms lar) C19 -3.3-µF, 6 -volt tantalum R 15,R 16-470 ohms Misc.-Mallory SC -628 Sonalert or C22 -2.2-µF, 6 -volt tantalum R17-51,000 ohms LED, 8 -ohm dynamic speaker (if Siren C24 -0.047-µF, disc ceramic R18-270 ohms Driver module is omitted), printed cir- DI,D2-3-ampere, 100-PIV rectifier R19-75 ohms cuit board, standoff insulators, snap -on D8 through DI4-1N4001 rectifier R20,R21-6200 ohms heat sinks for Ql and Q26 (Wakefield DI5--4.7-volt, I -watt zener diode R22.R28,R33,R35-10,000 ohms 291.80ABC2orsimilar), silicone thermal (1 N3825 or equivalent) R23,R24,R27,R32,R41-5100 ohms compound. suitable enclosure measur- FI-I -ampere fast -blow fuse R25,R26-4300 ohms ing approximately 10" X 5" X 31/4" or IC3-ULN-2232A Sprague Integrated R29-6800 ohms 25.4 cm X 12.7 cm X 8.3 cm (Bud

Motion Detector R30-560,000 ohms RC I 1 100 or similar), barrier block ter- QI,Q26-2N4921 npn silicon transistor R31-62,000 ohms minal strip, hookup wire, solder, hard- (or equivalent) R34-110,000 ohms ware, etc. Q8,Q 10 through Q23-Sprague RT I O8 R36-33,000 ohms Note-The Sprague ULN-2232A late-

npn silicon transistor (or equivalent) R37-82,000 ohms = grated Optical Motion Detector can be Q9,Q24,Q25-Sprague RTIO6 pnp sili- R38-3600 ohms purchased for $7.85 (plus $1 postage con transistor (or equivalent) R39-43 ohms Mid handling in U.S.) from Sprodco

The following are 5% -tolerance. 1/4 -watt R40-1300 ohms Marshall Street, North Adams, MA carbon -composition resistors, unless 01247.

TRIGGER 9? OUTPUT

R29 / R30 R31 R34 6.8K 560K 62K 1105

ENTRANCE DELAY

021 w.ww R32 5.IK R35 D14 C17 r IOK 10009F 017 019 022

020 R37 R36 R33 82K 33K 1OK 023

R28 t_ IOK C22/1 C24 2.2yF .047 SF 024

C19 3.3 yF

10 IC3 AUTO RESET 2232A irinuted by circled letters correspond to those in the system wir- C1e .475F 5 ing guide (Fig. 12) to simplify interconnection of Opdec modules. R38 3.6K

R40 1.3K ALA R M R39 GENERATOR 4311 range of several decades of light inten- which in turn drives A3. Capacitors Cl, sity while restricting signal dynamic C2, and C3 act together to favor low - range to a convenient level. Changes in frequency voltage changes such as R41 SIP the amount of light irradiating the photo - those resulting from sensed motion and diode result in a varying current and to discriminate against relatively high - thence a varying logarithmic voltage at frequency input signals such as those by the output of Al. Capacitor Cl couples 120 -Hz fluorescent lamp flicker. SPEAKER voltage changes to voltage amplifier A2 The logarithmic conversion charac- DRIVER

MAY 1980 63

AmericanRadioHistory.Com cially cónstructed detector module V+ (more on this later) should be mounted in O DI 1) a window and aimed at the sky. When a I 1 RI RI3 Íg+S lightning flash occurs, this detector will 10011 4311 2W 4W momentarily disarm the system and then QI automatically rearm it. This module D2 should not be mounted in such a way that any swaying trees, moving cars, or

CI similar objects are in its field of view. I0,000yF 1 +VREG .JD15 +VREG If you would like to incorporate the .4.7V IW i additional protection of a closed -loop yGND y system, magnetic reed door switches (normally closed) and metallic foil tape L_ -J for glass can be connected to the signal processor. These items can be pur- Fig. 3. This power supply can satisfy current demand of a complete chased at most electronics stores and Opdec system. Most of it .tits on Processor's pc the Signal board. are simple to install. The switches and tape are all wired in series and connect- teristic of A 1 and the gains of A2 and A3 C20 is charging, the pulses appearing at ed to point J and ground (point E). If any are chosen so that the threshold detec- the collector of Q9 are shunted to of the protected doors are opened or a tor is triggered when the change in light ground by 010. When the voltage foiled window is broken, the closed -loop level exceeds ±5% during a relatively across C20 increases to approximately circuit is opened. This cuts off 012, short period of time (about one second). 2.1 volts, Q8 conducts and cuts off Q10. which in turn allows the latch to be set When the threshold detector is trig- The Opdec system is now armed. by means of R21, D11, and D12. After gered, a pulse is routed to pin 11 of the If light -level changes such as those the 30 -second entry delay interval, the IC and to a four -bit counter that is part of caused by motion are detected, pulses alarm is activated. the chip's timing and alarm -generating are sent to Q9, which sets latch An additional feature of the Opdec circuit. An on -chip transistor is capable 015016. The latch cuts off 021 enabl-. Signal Processor module is either a of driving a small loudspeaker, but it is ing C17 to charge through R34. During visual or audible indication if any of the not used in the Opdec system. Rather, the interval that C17 is charging (ap- doors or windows are inadvertently left the pulse appearing at pin 11 of the IC proximately 30 seconds), the alarm is open upon exiting. If, for example, a sensor is applied to the Signal Proces- not activated. This delay gives the occu- window were left open, Q12 would be sor, the central, supervisory module of pant time to enter the house and disarm cut off and Q13 and 014 would conduct. the Opdec system. the system. When the voltage across Either a Mallory Sonalert or a light emit- C17 equals approximately 1.3 volts, ting diode can be employed to indicate The Signal Processor is shown sche- Q22, Q23, and Q24 conduct and that the Opdec system has been matically in Fig. 2. Among other things, it actuate the alarm generator comprising ordered to arm itself. The indicator can detects trigger signals from any of sev- IC3 and drivers 025 and 026. The be connected to the collectors of 013 eral motion sensors, decides if the sen- sound produced by IC3 is similar to the and 014 (point P). If you decide to use a sor has in fact detected the movement "yelping" sound made by police sirens. LED, make sure you insert a 560 -ohm of an intruder (rather than being trig- Once the alarm generator has been resistor between the cathode of the LED gered by lightning, a car passing in the activated, it will continue to oscillate for and the collectors of the transistors night, or some similar phenomenon), 10 minutes. After that time, it turns off (point P). Once the system has been generates exit and entry delays, auto- and the Opdec system automatically armed, the warning circuit is disabled by matically resets the system a few min- rearms itself. This feature is included in 011, which begins to conduct and cuts utes after it has sounded the alarm, and case the alarm is triggered while the off 013 when C20 has charged suffi- provides optional closed -loop periméter occupants are away for an extended ciently. protection. Also included in the signal period and no one is able to turn off the processor module is a power supply for alarm. This 10 -minute reset function is The Siren Driver. There are several the complete system. This supply is generated in the following manner. When different means of signalling that the shown schematically in Fig. 3. Q24 begins to conduct, it provides base Signal Processor has been triggered. In When the system is armed, S1 is drive for 020. This transistor cuts off the author's installation, the collector of opened. This allows C20 to charge Q19, which allows C21 to charge Q26 (point I) was connected to an exist- through R14. In the meantime, Q8 is cut through R30. It takes this capacitor ing intercom system and to two exterior off and allows Q10 to conduct. Transis- approximately 10 minutes to charge up paging horns. In addition, a 12 -volt, bat- tor Q 10 ensures that the latch consist- to a voltage which causes Q18 and 017 tery -operated electronic siren was incor- ing of Q15, 016 and their associated to conduct. When Q17 turns on, it resets porated as a back-up alarm in case resistors is reset. While C20 is charging the latch, which turns off the alarm. there was a power failure, or the power (approximately one minute), the occu- Opdec is again armed and awaits any lines were cut. An 8 -ohm horn speaker pant can move about the premises free- further trigger signals. can be connected to the collector of ly and leave through a protected exit Special precautions must be taken to Q26. The resulting loud alarm sound without setting off the alarm. Trigger prevent Opdec from generating false should bé sufficient to scare away any pulses from the motion detectors he alarms due to lightning, passing cars intruder. passes cause Q9 to conduct, but while with glowing headlights, etc. One spe- The electronic siren driver is shown 64 ( Continued on page 66)

AmericanRadioHistory.Com Fig. 4. Etching and drilling guide for motion and lightning sensor pc boards (shown above.) Fig. 6. Etching and (billing guide for the Siren Driver module's printed circuit board is shown above. Artwork for this and the other two pc boards on this page appears full-size. Fig. 5. Etching and drilling guide for Signal Processor module pc board (shown below).

signal procéssor board

MAY 1980

AmericanRadioHistory.Com schematically in Fig. 7. Signals ap- Finally, if because of some emergency pearing at the collector of Q26 are cou- you want to instantly activate the siren, PARTS LIST FOR pled to Q5 by means of D6 and R8. close the optional, PANIC switch, as- MOTION SENSOR MODULE Capacitor C23 filters the pulses pro- suming that it has been installed. duced by Q26. Transistor Q5 provides C2,C5,C6-47-µF, 6 -volt electrolytic base current for Q6 which in turn sup- Smoke and Fire Detection. Although C3 -0.22-µF, 6 -volt tantalum C4 -0.01-µF, 50 -volt disc ceramic plies base current to siren driver Q7. the motion detector will detect smoke IC 1-U LN-2232A Sprague Integrated If the line -derived positive supply volt- and fire (because both cause changes Motion Detector age V+ is lost because of a power -line in ambient light), it is advisable to install Misc.-Printed circuit board. standoff in- failure or intentional disabling by the one or more commercially available, sulators, suitable enclosure measuring approximately 23/4" X 21/4" X 15/C or 7 intruder, the system will be powered self-contained smoke detectors be- -gym X 5.4 cm X 4.1 cm (Bud CU - automatically by a 12 -volt lantern bat- cause the Opdec system has to be 2100 -A or similar), barrier block termi- tery. In the event that the intruder armed if it is to detect smoke and fire. nal strip, hookup wire, solder, hard- locates the Signal Processor module Thus, the occupants of the premises will ware, etc. and cuts all the wires leading to it, 03 be protected while they are there even will sense a loss of voltage and activate though Opdec will not ordinarily be the siren driver by means of R5 and D5. armed. (Continued on page 68) PARTS LIST FOR LIGHTNING SENSOR MODULE

PARTS LIST FOR - C7,C10-47-11F, 6=volt electrolytic SIREN DRIVER MODULE C8 0.22-µF, 6 -volt tantalum C9,C1 I `4.7-µF, 6 -volt tantalum IC2-ULN-2232A Sprague Integrated Motion Detector 23-1-µF, 25'-volt electrolytic ohms - R4-200,000 Misc.-Printed circuit board, standoff iñ- D3 -ampere, 100 -PI V rectifier -3 R6,R7-75,000 ohms súlators, suitable enclosure measuring D4 through D7 -1N4501 rectifier R8,R 10-5 I ,000 ohms approximately 23/4" X 21/s" X 15/1" or 7 Q2,Q3,Q6-Sprague RTI08' npn silicon RI 1-30,000 ohms cm X 5.4 cm X 4.1 cm (Bud CU - transistor or equivalent R 12-470 ohms 2100 -A or similar), barrier block termi- Q4,Q5-Sprague RTIO6 pnp silicon tran- ohms - R42-360 nal strip, hookup wire', or solder, hard- sistor equivalent Misc.-Siren (Vexoñ 160, Radio Shack ware, etc. Q7-Sprague RTl 14 npn silicon transis- 275-488 or equivalent), printed circuit tor br equivalent board, standoff insulators, snap=on heat The following are 5% -tolerance, 1/4 -watt, sink for Q7 (Wakefield 296040AB or carbon -composition resistors. similar), silicone thermal compound, R2-10,000 ohms suitable enclosure, 12 -volt battery, bar- R3,R5,R9-20,000 ohms rier block terminal strip, eta.

12V BATTERY CH -

Ov+ Fig. 7. Schematic diagram of Siren Driver module appears HEAT DETECTOR at left.

V} OSENSE

OCND

SIREN

PANIC SWITCH i TO D6 SPEAKER O DRIVER L-- 66 POPULAR ELECTRONICS

AmericanRadioHistory.Com s - v R6 R 817

C3 - +n 02 05 RIO R8 C4 i - I + D7 4 . + . + . 07 \/, RII I C5 + V 3 IRi2 0 I ^C23 C6 C2 i R4

_ -D6

1 1 O O O C> O HEAT PANIC DETECTOR SWITCH

F ig. 10. Shown above is the component placement guide for Opdec system's Siren Driver module printed circuit hoard. v+ C7 Fig. 8. Component placement guides for

B 1 motion (A) and lightning sensor modules (B) appear above left. Also see Fig. 11.

Fig. 9. Component placement guide for the Signal Pro- cessor pc board, which includes power supply, is below. +VREG +nnv PERIMETER +VSENSE EOGND O O O O LOOP WIRING 0 / OO 1 F I I } 8 Ri3 -RIB- RI4 T I R25 f R22 .R117 h R26 0 12 'I 1 015 014 013 If Qg I 08l f 011 010 / 1 1 ' 1 815 R27 R24 R23 $'013 R20 1 -R16- I 1 R13 RI 16 I TO 1411-D112)1179 1 SEC ; DIO* TI C21 I -C24-- I , R28 -.1- i h+ - -09- 1\111:L 017 -I*-014- 018

I -R33-C22+ C'0 ' _ R29 RO R31 -R32- C11 I +

CÍ9 C18 o I + 114.

CI 1Q2293O1q 16pg12

ólsod R39 Ij R38

-R40-

R41

MAY 1980 67

AmericanRadioHistory.Com A B Fig. 11. Wiring diagrams for r i motion sensor (at far left) and U special lightning sensor (left).

housed in a suitable enclosure. The + NC= lightning and motion detectors should be C3 ce .22yF .22yF mounted in an enclosure measuring NC- ICI --NC NC IC2 -c-NC - approximately 23/4 X 21/8" X 15/a" C4 C9 .01yF/ 4.7pF (7cm X 5.4cm X 4.1 cm). Each printed d + aiyF circuit is mounted using 1/4" (6.4 -mm) A 5/16" (8 -mm) be ' C2 + spacers. hole should 47yF CII. drilled in the front of each sensor enclosure directly in line with the center of the ULN-2232A integrated circuit to allow J light to reach the IC. The circuits and circuit boards of the Because most smoke detectors do the assembly of the Motion Detector, motion and lightning sensors are identi- not detect fire, it is also wise to install Signal Processor, and Siren Driver mod- cal except for part number designations heat detectors (available at most elec- ules. Full-size etching and drilling guides and component (capacitor) values. trical supply houses) in areas where for printed -circuit boards for these mod- These are given in both the component instant flare-ups could occur (i.e. fur- ules are shown in Figs. 4, 5, and 6. The placement guides of Fig. 8 and the wir- nace rooms, areas where paint and thin- corresponding component placement ing diagrams of Fig. 11. ner are stored, etc.). These detectors, guides appear in Figs. 8, 9, and 10. Note A master wiring diagram for the which behave like normally open that there are two component placement Opdec system appears in Fig. 12. Inter- switches, can be wired in parallel to guides in Fig. 8. The first (Fig. 8A) is the connecting the modules will be greatly point C of the Siren Driver module and guide for the standard motion sensor, simplified if barrier block terminal strips ground. Whenever a heat detector and the second (Fig. 8B) is for the light- are installed on the module enclosures attains a certain temperature, it behaves ning sensor that momentarily disarms and connected to the appropriate circuit like a closed switch. It will then cut off the system and prevents false alarms. board foil pads. The strips should be Q2, which enables the siren driver via Mount all resistors first, then the letter -coded to agree with the scheme R3 and D4. The Opdec system need not semiconductors. The capacitors should used in Fig. 12 and the component - be armed for this to occur. be mounted last. Take care to apply the placement guides, and the wires used to minimum amounts of heat and solder interconnect modules should be color - Construction. Printed circuit construc- consistent with the formation of good coded. Because the cost of the ULN- tion techniques are recommended for solder joints. Each module should be 2322A IC sensor is comparable to that

SONALERT 56011 1/2 W

LIGHTNING :SENSOR O O O SIREN

SIA O

SIREN SIGNAL O DRIVER PROCESSOR / O POWER SUPPLY _V1 O O 22251 PANIC SWITCH Q O ol ® II7VAC HEAT / ?DOOR J DETECTOR 11 SWITCH MOTION.. MOTION SIB SENSOR '- SENSOR PERIMETER ADDT'L LOOP DEVICES WIRING FOIL TAPE

Fig. 12. Master wiring guide for complete Opdec system with optional closed loop and heat detector.

68 POPULAR ELECTRONICS

AmericanRadioHistory.Com of a quality magnetic reed switch, it can ficient natural illumination to permit oper- be used liberally throughout the prem- ation of the sensors. At night, however, ises to be protected. Each sensor mod- some source of artificial light will have to ule should be connected to the Signal be used. Readily available photoelectric Processor module using three lengths of or electromechanically timed devices flexible, stranded hookup wire (No. 22 or can be employed to automatically turn on such lights at dusk. Make sure that larger). Heavier gauge hookup wire (No. You'll save money, 18 or larger) should be used for the rest the artificial light sources are simulta- have fun, and learn - of the connections. neously activated and that one of them by building it yourself is placed near the lightning detector. = with easy -to -assemble Installation and Use. The siren and This module will momentarily disarm the Heathkit Computers. the Siren Driver module should be system, thus preventing the Motion Sen- installed in the attic or some other area sor modules from triggering the Signal See all the newest in where the intruder will not be able to Processor when power is applied to the home computers, video locate it readily. The Signal Processor lamps. terminals, floppy disk module can be mounted in any conven- systems, printers and Options. Depending on factors peculiar innovative software: to each site at which an Opdec system is to be installed, there are several DESIGN SPECIFICATIONS Send today optional changes that can be made. For ULN-2232A if you think that lightning or SPRAGUE INTEGRATED example, fir` your MOTION DETECTOR some similar phenomenon is not a problem in the area to be protected, simply FREE . Supply voltage: +3.0 to +4.5 volts eliminate the lightning detector. Also, dc you can mount a key -operated dpst Ambient temperature: + 10°C to switch outside the premises to be pro- eathki +40°C for use as S 1. If this is done, the Current demand: 20 mA maximum when tected Catalog Vcc equals +4.5 volts exit and entry delays will no longer be Minimum sensing range: 8' (2.4 m) needed. Accordingly, the following Sig- Sensitivity: AL= ±5% at 1 Hz nal Processor components can be elimi- Ambient light: 0.1 fc to 100 fc (1.08 lux nated: transistors Q8, Q 10, and 011; to 1076.4 lux or 1.08 lumens/m, to 1076.4 lumens/m2) diodes D8, D9 and D10; resistors R14, Alarm sweep: 200 to 1000 Hz R15, and R16; and capacitors C17 and Alarm sweep rate: 5 Hz C20. If this is done, connect the position Audio output: 100 mW continuous lug of both portions of the dpst switch to Device fabrication: Monolithic IC con- E. switch pole to the taining linear amplifiers employing pnp point Connect one and npn bipolar junction transistors; base of 013 and the other pole to that I°L gates, counters, and D/A convert- of 015. er; low -leakage photodiode; and bipo- If you prefer to have the alarm remain lar junction power transistors. on indefinitely after the system has been 1. II triggered, eliminate the automatic time- out feature. This is done by omitting the ient area such as an entrance closet. As following Signal Processor components: was mentioned earlier, any attempt to transistors Q17 through Q20, diode tamper with the Signal Processor mod- 014; resistors R28 through R31, and ule will set off the siren. The ARM/DISARM R33; and capacitors C21 and C22. switch, S 1, should be located in a con- Finally, if a back-up battery power If coupon is missing, write venient spot but not easily detectable by source is not needed, the Siren Driver Heath Co., Dept. 010-652, an intruder. module, the siren, and -the battery can Benton Harbor, MI 49022 The ideal number and location of be eliminated. If this is done, the collec- Motion Sensor modules in your Opdec tor of Q26 (point I) can be used to sink Send to: Heath Co., Dept. 010-652, system depends on the size of your current from the positive supply through Benton Harbor, MI 49022. home or office and the number of areas a dynamic loudspeaker to ground. Send my free Heathkit Catalog now. that need protection. Sensor modules I am not currently receiving your catalog. can be placed on kitchen counters, on In Conclusion. Opdec is an inexpen- TV receivers, or even mounted within a sive but sophisticated alarm system that Name suspended ceiling into which a (5/,s' can enhance the security of business or or 8 -mm) hole has been drilled. In decid- residential premises. Its optical sensors Address ing where modules are to be placed, can detect not only intruders but also keep in mind that they sense motion by smoke of fire. The system is thoughtfully detecting changes in light level. There- designed and is readily expanded to City State fore, do not aim a Motion Sensor module include heat detectors, closed -loop toward a window or any flashing lights. sense wiring, and a large number of CL -728 Zip During the daytime, there should be suf- optical Motion Sensor modules. MAY 1980 CIRCLE NO. 31 ON FREE INFORMATION CARD 69

AmericanRadioHistory.Com . -/ when you?re away? Radio Shack's Ultrasonic Alarm System knows. And tells the world! ...and it's only

Every day, people are victimized right at home, but with this alarm system, you can stop intruders in their tracks. It generates an invisible, 95* ultrasonic field that detects all motion within a living area up to 20 feet wide ' and 30 feet long. No intruder can go undetected. The system includes a loud built-in alarm, and you can also add an optional -extra super -loud siren or bell. Either way, the boldest intruder will be scared away and your neighbors will know exactly what's happening! See the Complete Line of SAFEHOUSE° The cabinet, with its simulated walnut finish, will look great in your Security Products home because it simply doesn't look like an alarm-only you know it's a at Your Neighborhood security system. With the Radio Shack ultrasonic alarm, there's nothing to Radio Shack Store install. Just plug it into any AC outlet, and aim.

When dealing with intruders, every second counts. Don't get caught with your guard down-visit Radio Shack today and let's talk about adding 24 -hour protection to your home. These two cards honored at most Radio Shack stores

A DIVISION OF TANDY CORPORATION FORT WORTH, TEXAS 76102 Radie Thaek OVER 7000 LOCATIONS IN NINE COUNTRIES 'Price may vary at individual stores and dealers.

70 POPULAR ELECTRONICS

AmericanRadioHistory.Com WHETHER you pedal according to a button, drive a liquid -crystal display that the switch closes. Thus, a series of strict exercise regimen or just for is highly legible in the brightest daylight. momentary switch closures is generated fun, you probably want to know how far Accuracy of the odometer is limited by when the bicycle is in motion. you travel on your bicycle. Presented the tenth -of -a -mile resolution of the dis- The reed switch is connected to the here is an electronic odometer for play. Parts count is low, and, thanks to rest of the project by a short length of cyclists that allows you to do just that. the use of CMOS ICs and a liquid -crystal two -conductor cable terminated with Its design provides advantages lacking readout, the circuit draws very little cur- subminiature phone plug Pl. This plug is

in many commercially available odomet- rent from its self-contained battery pow- inserted into matching jack J1. When S 1 ers. Wheel motion is sensed magnetical- er source. is open, the CLOCK input (pin 10) of 12 - ly, obviating drag, slippage, noise gener- stage binary counter is at Vol:). During ation, and sensitivity to misalignment, About the Circuit. The Electronic the brief interval that S1 is closed, the one or more of which can characterize Odometer is shown schematically in Fig. counter's CLOCK input is at Vss. It is in this the mechanical sensing systems em- 1. Travel is measured by means of S1, a manner that the series of switch clo- ployed in many commercial products. magnetically actuated reed or LC2 mer- sures is converted into a train of clock Digital counters tally the number of cury -film switch mounted on the bicycle pulses that counter 1C2 can process. wheel revolutions sensed and convert frame. Each time a magnet on the rim of This counter is triggered by the nega- this number into the total distance (in the front bicycle wheel passes near the tive transition of each clock pulse. When miles) travelled. The counters, which switch (which occurs once each time it has counted 74 of them (equalling a can be reset to zero at the push of a the wheel makes a complete revolution), tenth of a mile traveled for a bike with How Far Did You Cycle Today?

BY ARTHUR V. CLARK

Low-cost electronic odometer indicates distance traveled in miles on a three -decade liquid-crystal display

AmericanRadioHistory.Com 53 OISI . S2 / RESET LXD 34DXX02X

V00 37 21

38 20 'TENS b 39 19 RI 81 C 20K -- 4.5V 40 Iei' d 2 17

3 22

16 ... 16 4 23 9 VDD VDD 4 12 9 27 aCLOCK Q7' CLOCK QQ 00 6 25 5 8 7 28.Q1 Q4 01 a 24 UNITS' 7 J 6 29 b 02 CM 02 02 8 15

12 s1 4 5 30 14 CI '- CM 03 Q3 d .001 13 10 13 f IC2 IC3 yF IC4 ICS e 1 4040 4023 4553 I DF411 2 26 2 31 } NC DSI DSI 27 32' TO DI D52 IN914 ICI PIN 6 I i 10 15 331 RESET RESET D53 D53 13 30 c V55 DIS VSS LE TENTHS - - 12 4 NC I 2

10 NC C 6 10 d 9 e 31

32 R2 9 5 IK B ABACK PLANE

34 135

S, 6, 7, 8, Op 12, 28, 34, 35, 36, 37, TOP N16 (ALL UNUSED DIS' PINS OF DISI)

BICYCLE FRAME

Fig. 1. Schematic diagram of the bicycle odometer. Counter 1C2 converts closures of S1 into pulses representing distance traveled. These are tallied by ICS and displayed by DISI.

27 -inch wheels), pins 4, 5, and 7 are at logic one (VDD). These logic levels are PARTS LIST applied to the three inputs (pins 1, 2, and 8) of NAND gate IC3A and cause its output (pin 9) to go to logic zero. This BI-Three series -connected 1.5 -volt al- SI-Normally open reed or LC2 mercu- kaline or NiCd cells negative -going pulse clocks IC4, a ry -film spst switch CI -0.001-4F disc ceramic S2-Spst toggle switch three -decade counter/BCD decoder C2-390-pF disc ceramic S3-Normally open momentary pushbut- with multiplexed outputs. The pulse is D1.-1 N914 silicon switching diode ton switch also applied to NAND gate IC3B, which DISI-LXD 34DXX02X liquid -crystal Misc.-Printed circuit board, IC sockets inverts it to provide a positive -going seven segment display or Molex Soldercons, suitable enclo- 101-CD4049 hex inverter sure, No. 16 AWG wire, wood reset pulse for 12 -stage binary counter brass or IC2-CD4040 12 -stage binary counter' aluminum block, two -conductor cable, IC2. The binary counter then starts to 1C3-CD4023 triple 3 -input NAND hookup wire, battery holder, printed tally the clock pulses generated by Si gate circuit board standoffs, solder, epoxy during the next tenth of a mile. 1C4-F4553 or MC 14553 3 -decade coun- cement, permanent magnet, etc. ter/BCD decoder with multiplexed out- Each clock pulse applied to pin 12 of puts Note-The DF4l I display driver is man- IC4 is counted and stored in the chip's ICS-DF4I I multiplexed BCD -to-seven - ufactured by Siliconix Inc., 2201 Lau- latch, up to a maximum count of 999. segment decoder/liquid-crystal display relwood Road, Santa Clara, CA 95054. Because each pulse corresponds to a driver The LXD 34DXX02X liquid-crystal tenth of a mile of travel, the maximum Jl -Subminiature phone jack display is manufactured by Liquid Xtal P1-Subminiature phone plug Displays Inc., 24500 High point Road, tally will signify a total distance of 99.9 RI -20,000 -ohm, 1/4 -watt, 10% carbon - Cleveland, OH 44122. A suitable LC2 miles. This stored information is time - composition resistor mercury -film normally open spst division multiplexed and presented se- R2 -1000 -ohm, I/4 -watt, 10% 'carbon - switch is manufactured by Fifth Di- quentially, one BCD digit at a time, at composition resistor mension Inc., Box 483, Princeton, NJ 08540. output pins 5, 6, 7, and 9.

72 POPULAR ELECTRONICS

AmericanRadioHistory.Com Fig. 2, Full-size etching and drilling guide .52 for a suitable printed circuit board is at left.

DISPLAY . DRIVER ItttIIiIt!11!!111t!i a DISI a,.. '9a ., -tn, o td .

Fig. 3. Component . layout for the printed circuit board is at right. iulllIisÉuuuiIiu

Anon -chip oscillator, whose frequen- demand is very modest, long alkaline for some close work, so be sure to use a cy is determined by the value of C1, cell life (or, in the case of NiCd bat- tine -tipped soldering pencil and small - governs the multiplexing of the BCD teries, extended intervals between re- diameter solder. When soldering compo- digits and provides DIGIT SELECT control charges) can be expected. nent leads to the board, apply the mini- heat and solder needed pulses at pins 2, 1 and 15 of /C4 for the mum amounts of multiplexed LCD driver. Logic levels Construction. The use of a printed cir- for good connections. appearing on these stobe lines are cuit board is recommended because it A single -sided printed circuit board is inverted by IC1A, IC1B and IC1F to be results in a compact, rugged assembly. employed to simplify its fabrication. This compatible with the levels required by A full-size etching and drilling guide for a means, however, that several insulated /C5. The BCD numbers presented at pins suitable board is shown in Fig. 2. The jumpers must be used. These jumpers 5, 6, 7, and 9 of IC4 are applied to the corresponding component placement must be installed first, because compo- input terminals (pins 27 through 30) of guide is shown in Fig. 3. This board calls nents will be mounted on top of them. IC5, a BCD -to -seven -segment decoder/ Next, install the fixed resistors, capaci- latch/multiplexed driver designed for tors and convenient lengths of flexible use with a liquid -crystal display. hookup wire that will be used to connect This complex chip's multiplexing func- the circuit board to the battery holder, tion and the ac drive required by the switches, and phone jack. liquid -crystal display are generated by The last components to be installed an internal oscillator whose operating .REFLECTOR are the semiconductors and the display. frequency is determined by the value of Be sure to orient each semiconductor JJJ, its and pin C2. The outputs of /C5 drive directly the J'JJ carefully, observing polarity active segments of DIS1, a three -digit -MAGNET basing. Follow the standard procedure liquid -crystal display. At the same time, for handling MOS devices. The use of IC the common back plane of the display is sockets or Molex Soldercons will mini- driven by a voltage that is 180° out of mize the risks posed to the chips by phase with respect to the voltage improper handling, the application of applied to the activated segments of the excessive heat during soldering, etc. Be WOOD OR REED sure to inspect your work carefully for display. In accord with good design ALUMINUM SWITCH practice, the unused inputs of CMOS BLOCK solder bridges. logic chips /C/ and IC3 are committed to In the author's prototype, that portion logic zero. of the circuit board containing the liquid - BICYCLE Power for the Odometer circuit is pro- °RAME crystal display was sawed and sepa- rated from the rest of the board. It was vided by B1, the series connection of Fig. 4. Details of the three 1.5 -volt alkaline or rechargeable author's actuating magnet/motion then interconnected with the display NiCd cells. Because the circuit's current sensor switch assembly. driver using convenient lengths of flexi- 73 MAY 1980

AmericanRadioHistory.Com ble hookup wire (using Fig. 3 as a guide) inserted into this hole and secured with and was stacked above the printed cir- epoxy cement. A drawing of the com- Get down cuit board by two slender rods made plete switch and magnet assembly to business from No. 16 AWG brass wire running devised by the author appears in Fig. 4. through holes drilled in the board and Note that the switch block was cut in with Rainbow through corresponding holes in the dis- half after drilling a hole in it correspond- play board. This assembly was secured ing to the diameter of the bicycle fork's Here's a sampling of software and hardware for together by means of epoxy cement. tubing. This allows the block to be Apple- II from Rainbow Computing-your one-step Apple center. You'll see what we mean when we say An enclosure for the project was secured to the fork by means of retain- Rainbow gets down to business. made from the case of a defunct calcu- ing screws. Note also that the reed +WRITE -ON! lator by cutting it in half and cementing switch was installed in another hole A multi -faceted, professional word processing system. Needs Applesoft and 32k. On disk with operating the end cap back on with epoxy. A drilled in the block. manual. Quick and easy -to -learn.

WRITE -ON I threaded bolt was run through a hole You can edit, move, delete, find, change and repeat drilled in the case and cemented to it Checkout and Use. Connect the any body of text: merge and save on disk. Does right-lustified margins, centering, page numbering. with epoxy. This bolt and a matching probes of an ohmmeter to P 1 and lift the You can enter name and address onto form letters wing nut permit quick, easy installation bicycle frame so that the wheel to which when printing. Edit and merge awry text disk file-even files not created by WRITE-ON-and and removal of the project from the bicy- the actuating magnet has been attached spool text to disk for letter printing or editing. Chain cle's front reflector bracket. Connection can turn freely. Rotate the wheel and up to 100 files in a single printer run .... $99.50 WRITE -ON II of the circuit common to the bicycle note the ohmmeter reading. It should Your data file merging system that can output a personalized form letter, check or document for any frame is accomplished by the mounting indicate an open circuit until the actuat- or all names on a mailing list. You can create and bolt, wing nut, a solder lug and the ing magnet passes near the reed switch, maintain mailing lists or other data files. Or, produce mailing labels. Its preformatted files speed up reflector bracket. at which point a short-circuit reading output on unbuffered or ultra hi -speed printers $150.00

FILEMASTER I Here's a powerful data file manager giving you two programs-FORMAT 8 RETRIEVAL. It handles everything from phone lists to legal abstracts. You can dsign your own data structure with up to 500 , r characters per record and up to 15 searchable fields Eaci +7 r. 3 -- in any combination. Needs 32K. On Disk 549.95 +FILEMASTER II

Has all the same features of FILEMASTER I plus allows for totaling, advanced math routines, more

powerful print formatting, larger data fields, and disk - to -disk transfers. 599.50 +MINI -LEDGER P This practical yet easy -to -use bookkeeping system, o which may be used in conjunction with Programma's checkbook program (Disk -534.95). offers: (1) sales Ilt. i PIN Ñ i`lh:*+ t and cash receipts: (2) payments and expenses; (3) receipts file search; (4) business header: (5) sales ©," t and cash summary: (6) payment and expense summary: (7) general summary statement: (8) expenses file search: (9) receipts index I search: and, (10) .'1 expenses index I search. Needs Applesoft and 48K. I` `. On . .' Disk .. $59.95 Julo Ñ1 U4s1 tl0 Ól7HYN1 :_.., Inquire about our new retail or manufacturing inventory ! . !t 3OQ,:i AVIVAi1j11VH NOi111115, programs on disk, Applesoft, 48K. $79.95 each l: - +VERSAWRITER Plq' This digitizer drawing board, complete with a powerful software package on disk, lets you create any picture in color with high resolution graphics. It's ideal for mass graphics. You can trace, edit, save and recall e what you draw. It's a simple -to -use system for students, artists, engineers and graphic programmers. Has an 8W"x11" working area. New applications r added inclúde: Text Writer adds text to your pictures. You control size, color and direction of text: Electronic Drawing lets you create schematics and includes commonly used symbols for transistors. Internal view of the author's prototype odometer shows display, OPAMPS. and FETS: Distance/Area lets you compute circuit board and battery fit in a compact plastic case. distances on maps or area of any frame. Applesoft ROM and 32K required .. $249.95 Add $5 (U.S.) or $10 (Foreign) for shipping. The wheel -motion sensor switch is should be seen. If this does not occur, To order, add $2 (U.S.) and $5 (Foreign) for shipping. California residents add 6% sales tax. Sorry we installed by securing a normally open adjust the position of the switch assem- cannot ship to P.O. Boxes. VISA/BANKAMERICARD reed switch to a block of wood or alumi- bly until a switch closure is obtained and MASTERCHARGE welcomed! + =Apple Plus compatible. num with epoxy. This block is then each time the magnet passes the secured to one of the bicycle forks. Eith- switch. er the front or rear fork can be used, but Now plug P1 into J1 and apply power it on The should read AAII780w COMPUTING installing the front fork permits the to the project. display

r ry use of a shorter cable (terminated in 00.0. If it indicates some other number, subminiature phone plug P 1) to connect momentarily depress S3. Rotate the Garden Plaza Shopping Center Dept. the switch to the rest of the circuit. wheel a total of 74 revolutions. The dis- 9719 Reseda Blvd. The actuating magnet is installed by play should now register 00.1. If it does, Northridge, CA 91324 Telephone (213) 349-5560 drilling a suitable hole in the plastic the project is working properly, and you ©1980 Rainbow Computing, Inc. reflector of the appropriate wheel. A are now ready to take your first bicycle CIRCLE NO.62 ON FREE INFORMATION CARD strong permanent magnet should be trip with an Electronic Odometer. K

74 POPULAR ELECTRONICS

AmericanRadioHistory.Com orló 'first an ciar-.Guaranteét were é oútperfprm: any watch sold today. .. or, costs you nothing! STAINLESS STEEL CASE The Súnwatch; acclaimed as SEALED MICRO most` ELECTRONIC the most accurate, MODULE versatile, most rugged °(NO OPENINGS swatch ever made: OF ANY KIND) 0 CONTAINING: Dt; SOLAR CELLS These features make all other POWER watches obsolete: STORAGE SYSTEM VISUAL DISPLAY & Clearly visible by day or night , EXCLUSIVE SUNWATCH Natural side -view window MICRO -CIRCUIT simplifies reading MAGNETIC SENSORS ! 100% solar -powered, you never AGNETIC. SLIDESWITCHES replace batteries Unique and memorable gift NO resetting of calendar, not Oven in Available in a special gift -box (see order form) the leap years Sunwatchi makes an ideal gift for special holidays, birthdays, graduation, Father's Day, 'etc. Perfect for Space age accuracy business people, commuters, teachers, athletes and Now you'll never worry about accuracy again. Because sporstmen, who require split second accuracy the Sunwatch will keep you,on time for the rest of your Free custom engraving life. (Accurate to within 1 sec. per month.) At your request, each Sunwatch will be hand -engraved Solar age efficiency with the name you specify. Miniature solar cells automatically convert sunlight, Limited Warranty is your protection daylight or ordinary bulb light into usable energy for The Sunwatch is covered by a 2 year limited warranty storage. The solar cells last virtually forever. So you'll Shock resistan to zo,duu or-- issued by Riehl Time Corporation (manufacturers of the never replace a watch battery again. You can'crash it into a rug -surfaced brick wall at 90 prestigious Synchronar 2100) and included with your Programmed for over a century mph with no noticeable effect. Wear it while doing watch. A copy of the warranty may also be obtained The built-in computer on a chip will always display the heavy work, exercise or any strenuous activity. free of criarge by writing to Riehl Time Corp., 53 S. correct time date and month. Also, it automatically Temperature resistant Jefferson Rd., Whippany, NI 07981. This warranty adjusts the watch calendar for long and short months, Put the Sunwatch in boiling water for 30 minutes, gives you specific legal rights, and you may have other leap years and it's programmed until the year 2100! freeze it in a block of ice for a year. Extreme tempera- rights which vary'from state to state. tures will not damage your Sunwatch. Easy to read 15 Day no risk trial offer The natural side -view display lets you tell the time, day Pressure resistant and date without twisting your arm into an uncomfort- There are no air spaces inside the Sunwatch. There- Order your Sunwatch today and use it for 15 able position. fore, it is not susceptible to high pressures such as days. Then, if you are not completely satis- Numbers always visible might be encountered diving to great depths. fied return if for full money back. Four varying light intensities are built into the viewing The perfect watch far a lifetime display, 'allowing the Sunwatch to adjust automatically Imagine split-second accuracy for the rest of your life. CREDIT CARD ORDERS CALL to any light. This means you can always read it, even Sunwatch is a virtually indestructible, beautifully TOLL FREE 800-621-5199 in three in the brightest sunlight. styled, space-age timepiece, and it's available ID. Residents Call 800-972-5855 exciting Brushed stainless steel, Gold tone 10 Display functions finishes: OR MAIL THIS NO RISK COUPON The Sunwatch is capable of displaying the following stainless steel, or a Durable black finish on stainless information: hours minutes seconds months date steel. All Sunwatches come with a matching stainless day leap year speed calibration AM/PM indicator steel band 'with removable links and adjustable clasp. rRIEHL TIME CORP. S.lefferson Rd., Dept. 44 Whippany, NI 07981. seconds count -off. Made in the United States 53 Extreme accuracy The Sunwatch, designed by Roger Riehl, was being Please send mu: Unlike other electronic watches using tuned crystals to worn by its inventor nearly a year before the first Brushed Stainless Steel Sunwatches control timing accuracy, the Sunwatch incorporates a electronic digital watch was even available to the gen- at $129.95 each unique, programmable, microcircuit synthesizer to eral public. Since that time constant engineering evalu- Black Finish on Stainless Steel Sunwatches make it the first watch in history that is accurate to less ations and design improvements have been made on at $159.95 each. than 1 second per month. That's 5 times more accurate the Sunwatch to incorporate the latest in digital micro- Gold Tone Stainless Steel Case Sunwatches quartz Accutron. technology. Thus the Sunwatch than the latest circuit and solar power at $159.95 each. today represents state-of-the-art electronics technology. The Power Source Hour (Military Time) $10.00 Additional. Tiny silicon power cells, which are constantly being It is built to the same rigid standards practiced by the -24 Gift Boxes at $4.95 each. energized by natural sunlight, daylight or an ordinary manufacturer in creating sophisticated computer micro- Please add $3.95 per watch shipping and insurance. light bulb keep the Sunwatch energy storage system circuits for the U. S.. Government and other major Enclosed is S Check or Money Order charged. Should the watch not be exposed to light, it users of these components. (N.1. Residents add appropriate sales tax' will continue to operate for months on stored power. * A word about other "Solar Watches" CHARGE 1T. (Check One) The most indestructible watch in the world Roger Riehl, designer of the Sunwatch, states that The workings of the watch: solar panels, energy cells, there is no other completely solar powered watch on Master Charge VISA (BankAmericard) quartz crystal, computer on a chip, etc., are all perma- the market today. Claims of solar power by other watch Bank# nently sealed in a Lexan module. This module is so manufacturers are based on the use of a small solar Credit Card# unique it's protected by U.S. and foreign patents. cell. Due to their limited size, these cells can be proven, Issue Cate Exp Date Completely waterproof in technical terms, to be of virtually no significant value Signature Leave the Sunwatch in salt water for months. Dive with in extending the life of a watch battery. For this reason, Name to be engraved It in depths up to 750 feet. There are no openings - all other so-called "solar watches" must have replace- Name magnetic slide bars activate all functions. With Sun - able batteries. The Sunwatch's power storage system, watch's exclusive, permanently sealed Lexan module, however, need never be changed and is, in fact, perma- Address there are no "0- rings or sealsto leak. nently sealed to withstand abuse and the elements. City/StateiLp Quick delivery direct from the manufacturer CIRCLE NO.64 ON FREE INFORMATION CARD

AmericanRadioHistory.Com NOW AVAILABLE! it' -

I'll,OO 10 10 >l0 DO ..OIJMT ~not WATT WIZARD" ..ptimoic. POWER FACTOR CONTROLLER CUTS THE COST OF RUNNING ELECTRIC APPLIANCES BY AS MUCH AS 50% -- AND YOU CAN EVEN SEE THE SAVINGS! For over a year now, in magazines and newspapers the world over, there have been enthusiastic write-ups on a National Aeronautics remarkable new device that can cut your and Space Administration I electric bill while helping the U.S. save Patent No. 4,052,648 huge quantities of fuel. "The NASA/Nola power saver," wrote a Popular Science senior editor, "was developed by Frank Nola at NASA's Right now, the typical consumer pays George C. Marshall Flight Center as an about $8 per month to operate a 16.5 cu. offshoot of a program to reduce power ft. frost -free freezer... $10 to run a 17.5 consumption in spacecraft motors. Nola cu. ft. frost -free refrigerator ... $8.25 for calls it a PFC power -factor controller. an attic fan operating 12 hours a day - and about $60 for an air conditioner I prefer to call it a power saver, however, ... because that's what it does." used during summer months. It's not OTHER MODELS AVAILABLE hard to figure out what you're paying per NASA TESTED IT Air conditioners, washers and dryers year just to run one of,these appliances. require wire -in model. If you lack According to Clyde S. Jones of NASA, And in many parts of the country, the mechanical skill, you probably need an "The device has been tested at Marshall cost is even higher. Center on over 40 types of motors, with electrician to install it. We also offer it in That's why Nola's power saver can 220 VAC single or three-phase. power savings ranging up to 60%, soon pay for itself, then start reducing depending on the loading. The motors your electric bills - the amount of sav- ADVANCE FEATURES tested were both single-phase and three- ings, of course, depending on which ap- The Watt Wizard also includes two more phase, ranging from 1/2 H.P. to 5 H.P. pliance(s) you usetit with. unique features. It's fused, so if you ac- Most motors will show up to 40 -to -50% There's just one catch. Until now, the cidently overload the device, it won't savings when running lightly loaded or device has not been available - except burn out. Just change the fuse, which is unloaded, and some will show 5 -to -7% for industrial models prices at $80 or available at any auto supply store. savings at rated load." more. And the Watt Wizard features an LED NASA's Technical Support Package INTRODUCING THE WATT WIZARD readout, so you can actually tell, at any showed the test results and noted that moment, exactly how much power you're "The Power Factor Controller applies to Cynex, an American manufacturer of saving - 10%, 20%, 30%, 40% or 50%. electrical and a induction type electric motors - the electronic products and There's a "Power On" light, too. And most commonly used type in all major prime contractor for the U.S. Govern- the Watt Wizard comes with the ment, has been licensed by NASA to home appliances and the most common- manufacturer's 1 -year limited warranty. ly used by industry." manufacture Frank Nola's power saver. Cynex calls it the Watt Wizard. LOW COST - AND A TAX CREDIT HOW IT SAVES POWER "The Watt Wizard," says Ray We're offering the Watt Wizard for on- Popular Electronics explained it this Beauchea, the firm's Marketing Director, ly $39.95, with immediate delivery. Want way: "AC induction motors character- "regulates the voltage fed into an induc- two? Then it's just $37.95 each. Or istically run at a nearly constant speed tion motor, reducing or boosting power splurge and get three at $34.95 each. that's fixed by power -line frequency and as required, when loads go up or down. Wire -in models for heavy duty motors are independent of load and supply voltage. Simply stated, it makes motors run more $6 more for each unit. Add just $2.50 When heavily loaded, the motor draws efficiently, especially when idling. It postage/handling for each order (not line current that is nearly in phase with reduces motor heat, affording longer each unit). the applied voltage ... Under light load motor life and reducing the amount of air And next year, when you fill out your tax conditions, the motor develops less tor- conditioning required for cooling return, you can deduct a full 15% energy que by allowing more lag between the (rooms) in summer months. It saves elec- tax credit - for additional savings. voltage and current. This reduces the tric power, because kilowatt hours are 30 -DAY MONEY -BACK GUARANTEE power factor while leaving the current greatly reduced. And it causes the motor Try the Watt Wizard for up to 30 days. essentially the same in magnitude. to run quieter." "Though the low power factor means If not completely satisfied, return it SIMPLE TO USE (insured) for a full refund. that conversion of electricity to The you send for Watt mechanical power is large Cynex makes several models of the sooner the small, the cur- Wizard, the more you can save on your rent causes considerable (heat) losses in Watt Wizard (all with solid state design), including the 110 V AC plug-in model electric bills. To order, send your check the supply lines and motor windings. money This is what reduces we're offering. It's for single phase frac- or order to the address below. Or efficiency. charge it to your Visa, MasterCharge, "To minimize this waste, Nola's tional H.P. motors (less than 1 H.P.) device American Express or Carte Blanche monitors the motor's power factor and, which is the type used in most made -for - credit card. If using your charge card, when it detects light load conditions, it the -home freezers, refrigerators, window and attic fans, swimming pool pumps,fur- you can also order via our toll -free phone reduces the supply voltage ... The cur- number: rent, now more nearly in phase with the nace fans, vacuum cleaners, sewing voltage, therefore does as much useful machines, power drills, etc. work as before, but it and the voltage are Simply plug the Watt Wizard into any 800-257-7850 smaller, resulting in a net savings of electric outlet, then' plug the appliance electrice power." into the Watt Wizard. There's no wiring (In New Jersey, Call: 800.322.8650) required. Unlike some competitor's N.J. residents, add 5% sales tax. THE SAVINGS CAN ADD UP models (if and when available), the ap- Or mail your order to: Like everything else, the cost of elec- pliance does not have to be turned on tric power keeps going up. Not only is before being plugged into the power Dept. P2', Lakewood Plaza the basic rate you pay going up, the saver. You can leave the appliance - Lakewood, N.J. 08701 power companies have now added on a whether on or off - plugged into the "fuel adjustment" charge to help pay for Watt Wizard all the time. Or you can running their generators. In 1980, 1981 move the Watt Wizard to various loca- and beyond, you'll pay more and more tions, depending on which appliance is mercu-41 for the privilege of running your electric being used. (Better yet, order several appliances. Watt Wizards.) The Imagination People® 76 POPULAR ELECTRONICS

AmericanRadioHistory.Com )

- BY FilÁNK `1. -61N

--jr. 0 o e a, a.4o_ 0o evng 9 0

_`,`, " ._ _ , + `, `

...... " .ITS'

vr,

EXPERL TING WITH A UNTIL a couple of years ago, experi- far more convenient. What makes the menting with sound -effects circuitry 76477 unique is that it contains all the was difficult, requiring a large bread- SO»1Mpi active circuitry needed to generate just board to accommodate oscillators of about any sound imaginable. A few various descriptions, modulators, noise resistors and capacitors and a power sources, mixers, envelope generators, supply are the only external components etc. Now, thanks to Texas Instruments' EFFECTS required. SN76477 complex sound generator, an integrated circuit that sells nationally for Inside the IC Package. By considering about $3.00, .sonic experimentation is GENERATOR its complex circuit as a series of function

With a minimum of extra components and a single Texas Instrument SN76477 IC, you can create a host of different sounds

MAY 1980 77

AmericanRadioHistory.Com /

"blocks," it is relatively easy to under- a nominal 0.1 -to -30 -Hz range, contingent signal is present or absent, the system stand and follow the 76477's operation. on the values d resistance (R) and inhibit logic controls the output of the In Fig. 1, the IC's function blocks are capacitance (C) connected from pins 20 envelope generator and modulator. This reduced to simplest form, with basic and 21, respectively, to ground. Two out- signal also toggles the one-shot multivi- in sound -generating blocks gray shading puts are available from this oscillator: a brator that is used to generate the short - and supplemental control blocks in 50% duty-cyclé square wave that is duration pulses used to simulate the color. Typical waveforms available at applied to the mixer and a triangular sounds of gunshots, bells, and explo- various points in the system and what wave that can be routed to an external sions. Time duration of the multivibra- the final output before amplification voltage -controlled oscillator (vco) via tor's output signal is determined by the might look like are also shown. pin 16 or through the SLF's select logic R and C values connected from pins 24 A more complete picture of all the block to modulate the internal vco. and 23 to ground. Maximum usable peri- function blocks contained in the IC's 28 - Modulation of the internal vco covers od is approximately 10 seconds. pin package is shown in Fig. 2. Fabri- a 10:1 range, with the lowest frequency The output from the one-shot multivi- cated from bipolar analog and I°L digital determined by the R and C values con- brator is passed through the envelope - blocks, this IC contains all the active nected between pins 18 and 17 to select circuit that. determines envelope circuitry needed for a user to create an ground. This vco's output goes to the shape and is used to modulate the almost unlimited range of sounds. . mixer and envelope -select circuits. envelopé generator and modulator.

SLF"' OSCILLATOR

JLJ uULJ UL

ENVELOPE GENERATOR & MODULATOR OUTPUT NOISE CLOCK, GENERATOR, & VAR. BW FILTER"'

ENVELOPE. ONE - SHOT SELECT MU LTIVIBRATOR CIRCUIT Fig. 1. This simplified block diagram of the operation of the 76477 shows, in gray shading, the blocks that generate the basic sounds. Supplemental control blocks * CONTROLLED BY EXTERNAL are in colored tints. CAPACITORS & RESISTORS SYSTEM INHIBIT LOGIC

Desired sounds are all user defined. Output pulses from the noise clock, Modulator attack and decay are con- You simply switch into and out of the whose frequency is determined by the trolled by the R and C values connected IC's circuit resistor and capacitor values resistance values connected from pins from pins 7, 8, and 10 to ground. and set a few logic states to "tailor" the 3 and 4 to ground, are used to control The final signal is applied to the audio audio parameter you require. Sounds of the noise generator. The output from the amplifier, which develops a 2.5 -volt gunshots, explosions, sirens, musical noise generator is passed through a peak -to -peak maximum low -impedance instruments, "phaser" guns, etc., can be variable -bandwidth noise filter, con- output at pin 13. A feedback resistor can simulated. You can even create sounds trolled by the R and C values from pins 5 be connected between pins 12 and 13 to you never heard before. and 6 to ground, to the mixer. modify the amplifier's gain. An audio amplifier is built into the IC, The mixer combines the three inputs There are 23 variables under user but you can route its output to a high - (from the noise filter, the SLF's square - control with the 76477 sound generator. quality audio amplifier to obtain a louder, wave generator, and the vco) and, con- Hence, you can be kept occupied for a richer sound. tingent on the dc states of its three considerable time exploring the effects selector inputs, at pins 25, 26, and 27, that can be obtained with various combi- Chip Operation. The super -low -fre- determines type of mixer -output signal. nations of controls. quency (SLF) oscillator in the 76477 has Depending on whether a 5 -volt control (continued on next page)

78 POPULAR ELECTRONICS

AmericanRadioHistory.Com Fun- Circuits

Yóu Can Build GUN 5H01 SIREN OR OR In this section, we.present five fun circuits EXPLOSION PHASER GUN that typify some of the uses to which. the SN76477 complex sound generator IC can be put. All are relatively simple and inexpensive to build, because the IC contains 4 IMAM all the active circuitry needed. 82K SHOT) Circuits A, B, and C can be used to add realistic sound effects to the animation in 330KIEKP) video games. The model railroader will find circuit D useful, while the electronic "organ" in circuit E should appeal to all, especially children. Finally, circuit F illustrates how an outboard transistor amplifier stage 200K 20 can be added to increase the power deliv- RATE 15 ered to the speaker.

C D RACING CAR STEAM TRAW ANO WHISTLE CRASH 1 +5V M/MM 251 27K -

19 17 .0101( 7 + -+5V

II.IpF 23 9I00F 28 - 47K= , ll 2 18 P0 IM IOOK H +5V , 91479F .I7 il 3 21 1(.111F. 9 25 5 76477 39K 4 +5V 76477 26 27 47K 5 i-M/JvVJr- LIMIT 5K 390F 6

IOOK 100 K 10 RATE 10OK 2208F

R LIMIT 14 +9V

5= F É TYPICAL AUDIO ORGAN AMPLIFIER +5V

191-41°1-51 I' 17 25

47K 18 2

IpF ,4 23 47K 220K 24 --MM5 330K 470J1 16 B>- 6 390pF _1- 680R 76477 Moon AH (LOUDNESS) _L IK G:M 180K -L_ 1.5K ' 8 103F F r- --aNJMM 1.8K E- 10 1.51 2.2K 150K D ' J.__ 2.7 K ` C#-. 9L 10K Practical Breadboard. Shown in Fig. 3 3.3K t,01pf C - is the circuit of a practical experiment- 2N3703 er's "breadboard." Although the circuit 47K 47K is really quite simple, to utilize the full capabilities of the 76477 sound genera-

220K tor, a rather large cabinet is required to accommodate all the switches and ,+5V jacks shown. You can use a small piece of perforated board on which to mount /C/ (a socket is recommended) and the 01/ 02 audio amplifier circuit. Alternatively,

POPULAR ELECTRONICS 79

AmericanRadioHistory.Com VCO EXTERNAL PITCH SELECT VCO CONTROL CONTROL 22 19 76417 IRI `7 IRI 20 18

SUPER -LOW EXTERNAL VCO v.;[ OR VCO SLF FREO. OSC. SLF VCO CONTROL CONTROL SELECT'

17 Y-ThY ICI ICI

IRI NOISE 4 CLOCK

CONTROL / NOISE NOISE NOISE (RI FILTER GENERATOR FILTER CONTROL EXTERNAL NOISE CLOCK (RI 3 ICI

15 5V

14 REGULATOR 9VIn 9 SYSTEM MIXER INHIBIT SYSTEM LOGIC INHIBIT I. . > GND

12 FEEDBACK IRI

IC) 23

ONE- ENVELOPE ENV. GEN 13 ONE SHOT SHOT SELECT AND AMP CONTROL AUDIO MODULATOR OUTPUT

24 (RI

CAPACITOR ICI 28 26 25 27 7 181 - RESISTOR ENVELOPE MIXER ATTACK/ ATTACK DELAY AMPLITUDE SELECT SELECT DECAY CONTROL CONTROL CONTROL TIMING IRI IRI IRI ICI Fig. 2. The block diagram of the internal operation of a 76477 complex sound generator IC shows how i contains a complete sound -effects lab in a 28 -pin package.

you can design and fabricate a printed - function. Group arrangements can be circuit board. If you use perforated TABLE I-JACK IDENTIFICATION outlined on the control panel. with a board, you can Wire Wrap or pencil wrap J1 Input for external noise oscillator heavily inked or painted line. the components into the circuit. J2 Input for external voltage -controlled Once the various components are Although the system will operate from oscillator mounted on the front panel, refer to J3 Noise filter resistance a standard 9 -volt battery, you might opt measurement Fig. 3 and wire them into the circuit. for a small power supply that can deliver jack with R4 J4 Decay resistance measurement jack 7.5 to 9 volts instead, if only to free with R6 Use. Note in Fig. 3 that each IC pin that yourself from having to replace battéries J5 Attack resistance measurement jack terminates in a potentiometer has both a periodically. with R8 Make sure, however, that switch and banana or tip jack in series J6 Audio output the cabinet you select will accommo- with the pot. This J7 External vco permits you to use an date all controls,'jacks, and circuitry. measurement jack with R15 ohmmeter to measure the resistance All 28 switches, 12 banana or tip J8 Vco control resistance measurement required for a given sound, arrived at jacks, and 8 potentiometers should be jack with R18 experimentally. After obtaining the de- J9 Pitch control resistance measure- mounted on the front "control" panel sired sound, you simply open the switch ment with R23 and suitably identified with a dry -transfer jack J10 SLF oscillator control resistance for the pot and use the ohmmeter to lettering kit. To simplify experimenting, measurement jack with R25 measure the resistance from the asso- switches, and jacks, pots should be J11 One-shot resistance measurement ciated jack to ground. If you keep a log jack identified according to function as with R27 of the various resistances and capaci- J12 Commori ground shown in Tables I through III. Table IV is tances required for particular sounds, an example of grouping according to they can be duplicated on demand. 80 (Continued on page 82)

AmericanRadioHistory.Com ISOpF R4 R2 R27 NOISE <{ 47K IM FILTER +5V ONE-SHOT C23 .IyF 514 5151 +5v ENV. ENV. C24 S EL. SE L. 475F 2 " $16/ 28 MIXER ' C25 C 0 S20 I 917 -SHOT + MIXER ICÁPÁCITOR C26 A 10 F R6 $18 + IM MIXER C27 DECAY B 508F +

C 1 8 500pF

4 . C19 S13 SI9 .05yFI// NOISE OSC. ONE-SHOT 1 S9 SLF OSC C20 5 CAPACITOR yF ATTACK/DECAY 47 CAPACITOR 512 522 NOISE O C2I J3 =FILTER ,.47p F C9 -0'."149 +5V IyF VCO 10pÓ2F T CI+ SIO ICI OSC .110 + OOFY DECAY SLF 76477 . R8 20 S23/i PMs.^".11-211q,O' ATTACK J9 R24 R25 2.7 K I M _ -L.. 19 - +5Y .. ' . SlF OSC: R9 S24V'. g CONTROL ' ONE'SHOT PITCH LVvVWIE2K 0- + 5V "

. R22 R23

RIO , R7 50K 50K +- r 47K 2.7K - ' PITCH JVvtM, RI7 é i 2.7 K y,A, 526 RII J5 ÁTTACJ( j IOOK t00K - r IEI O---nNvVJJ-- VCO O ' RIM CONTROVCL VMti....- RESISTOR CONTROL - J8 VCO R20 R12 IM _ CONTROL ' tY 220K S4 12 7

8114_ - FEEDBACK O - ú INT -. ._. 33KVr-' 47K _ 13 16 S213 EXT

S3 VCO IOOpF- OUTPUT SELECTOR .12 - 14 15 EXT VCO CONTROL

S 27

SI - WOO CONTROL POWER CAPACITOR

+9V +5V .112 ' IN TO CIRCUIT GND CI? IyF

Fig. 3. The circuit far a complete sound -effects generator uses 28 switches, 12 banana (or tip) jacks and eight potentiometers to allow a broad selection of controllable parameters. PARTS LIST

B1 -9 -volt battery.(see text) J3 through J I2-pin or banana jacks R21-10 megohms -Cl-150-pF capacitor Q1 -2N3703 transistor. ,S1 through S4,S6,S7,SI0,S12 through C2-360-pF capacitor Q2 -2N3704 transistor S19,S21,S23 through S25-Spst slide 3C3 -0.001-µF capacitor The following arc 'h -watt; 10% resistors or toggle switch 5 -position non-; ' C4,C5-0.01-µF capacitor unless otherwise noted: S5,S20,S22-Single-pole, C6,C 14,C 19-0.05-µF capacitor RI -3900 ohms shorting rotary switch C7,C15,C20,C23-0.T-µF capacitor' R2,RI0,R14-47,000 ohms S8-Normally open, momentary -contact C8,C 16,C2I ,C24 -0.47-µF capacitor R3,R5,R7,R 17,R24,R26-2700 ohms pushbutton switch C9,C17,C25-I-µF capacitor R4,R6,R8,R 18,R25,R27-1-megohm S9,S27-Single-pole, 5 -position nonshort- ing rotary switch C l 0,C I I ,C22,C26=d 0-µF, 15 -volt elec- linear -taper potentiometer trolytic R9-22,000 ohms SI í,S26-Single-pole, 4 -position -non- switch C 12-I00-pF capacitor Rl 1,R I 9-1 00,000 ohms shorting rotary slide or toggle switch - C I 3,C18-500-pF capacitor R l 2-220,000 ohms S28-Spdt C27 -50-µF, 15 -volt electrolytic R13-330,000 ohms Misc.-Battery holder; 28 -pin DIP socket -transfer lettering kit; suit- ICI-SN76477N complex sound genera -- RI 5,R23 -50,000 -ohm linear -taper 'pi): for ICI; dry tor (Radio Shack 276-1765 or similar) tentiometer able enclosure; control knobs and dial JI,J2-RCA phono jacks R 16,R22-50,000 ohms plates (7); etc. R20-1 megohm

81 POPULAR ELECTRONICS

AmericanRadioHistory.Com Since the circuit can generate a very board. In this example, we will use the definitely not for wide variety of sounds, let us give an sound of a gunshot. example of you how might go about "tai- First, close FEEDBACK switch S3 and novices . loring- a ... specific sound with the bread - OUTPUT switch S4 to place the audio Dr. Dobb's Journal is the serious micro- amplifier in the circuit. Then close +5V computer journal of systems and soft- switch S2 to activate the ware. You won't find games and never- +5 -volt line. ending tutorials on "How to Program Main POWER switch S1 can now be in Basic" in You will DDJ. find useful TABLE II-SWITCH closed when you are information-algorithms, code for coma ready to experi- pilers, operating systems, editors, debug- IDENTIFICATION ment with the controls. gers, hardware evaluations, comparisons S1 Power switch for 7.5 -10 -9 -volt dc sup- Since a gunshot has fast attack and of architectures-all presented in a ply straightforward, direct fashion. relatively brief decay times, close ATTACK S2 Power switch for 5 -volt dc supply and DECAY If you are an expert who is serious about S3 Output switches S6 and S10, respec- microcomputers you should be reading. S4 Feedback tively, to permit you to adjust attack and Dr. Dobb's Journal. Buy it at your local computer store or subscribe. No need to S5 Amplitude resistance selector decay times via ATTACK and DECAY pots send money now, just send us your S6 Attack resistance R8 and R6. As you experiment with vari- name, address, and zip and we'll bill S7 One-shot, constant when closed you later. $ 15 one ous settings of these controls, for year (10 issues). S8 One-shot momentary close S9 Attack -decay timing capacitor selec- main POWER switch S1 and press and tor release ONE SHOT switch S8 to hear the Dr. Dobb's Journal S10 Decay resistance gunshot sound for each combination of S11 Noise filter capacitor selector P.O. Box E, Dept. G9, Menlo Park, CA settings. Adjust R6 and R8 and press 94025 S12 Noise filter resistance and S13 Noise oscillator resistor release S8 until the sound obtained is S14 Envelope select 1: logic 0, logic 1 "just right." (Calibrated index scales

515 Envelope select 2: logic 0, logic 1 behind each potentiometer control knob S16 Mixer C: logic 0, logic 1 will simplify recording of settings.) S17 Mixer A: logic 0, logic 1 Amusements If desired, required values of attack S18 Mixer B: logic 0, logic 1 S19 One-shot resistance and decay time resistances can be for S20 One-shot capacitor selector measured and recorded by opening the men and S21 Voltage -controlled oscillator (vco): ATTACK and DECAY switches and measur- logic 0, logic 1 ing with an ohmmeter between DECAY S22 SLF oscillator control capacitor se- machines lector jack J4 and ground and between ATTACK S23 SLF oscillator control resistance jack J5 and ground. ENVELOPE SELECT 1 S24 Pitch control resistance and 2 switches S14 and S15 can also S25 Vco control resistance be preset for the required envelope. S26 Vco control resistance selector To produce an explosion instead of a S27 Vco control capacitor selector S28 Internal/external vco selector gunshot sound, close NOISE FILTER switch S 12 and adjust NOISE FILTER control R4 for the desired effect.

TABLE Ill-CONTROL In Conclusion. The sound -effects gen- IDENTIFICATION erator breadboard presented here can R4 Noise filter control be used in either or both of two ways. R6 Decay control For the designer, it is a "tool" that sim- R8 Attack control plifies designing a circuit from scratch. R15 Vco control One can "design" a circuit R18 Vco control with the R23 Pitch control breadboard, measure resistances of the R25 SLF control controls and read off capacitor and R27 One-shot multivibrator control logic -state (+5V or 0) settings from the . panel, and assemble the circuit a í 1 - I around í '104 separate 76477 generator chip. The other way ' e to use the breadboard is to L TABLE IV-CONTROL GROUPING simply experiment with control and The magazine for the imaginative One -Shot Ji 1,R27,S7,S8,S 19,S20' switch setting combinations until you Noise Filter J3,R4,S 1 1,S 12 small computer user. hear a sound you like. Used in this man- VCO Control J7,J8,J9,R 15.R 18,R23,S21, ner, you can record a whole series of Published S24,S25,S26,S27,S28 bi-monthly, $10/year. sound Complete the form below or send us SLF Control J 10,R25,S22,S23 effects that can be used with your name and address. We'll bill you. Noise Clock S13 home movies and slide shows, for thea- Recreational Computing, Mixer Select S16,S17,S18 trical events, etc. Envelope P.O. Box E, Dept. G9, Menlo Park, CA 94025 J4,J5,R6,R8,S6,S9, S 10, Whichever way you use the bread- S14,S15 board, it is a good idea to log Name Amplitude S5 parameter Audio Output J6,S3,S4 values for given sounds for future refer- Address Power On /Off S1 ence. Then, any time you want to repro- +5 volts S2 duce a sound arrived at experimentally, City Ground J12 you can, simply by setting the controls State Zip and switches as detailed in your log. 0

CIRCLE NO.56 ON FREE INFORMATION . MAY 1980 82 CARD

AmericanRadioHistory.Com ject would be greately appreciated.- Hobby Scene/ Michael Wojtusiak, New York, NY. , A typical flash unit is shown schematically A. in the figure. When power switch S1 is closed, the oscillator generates square waves, usually at a rate greater than 20,000 Hz. These ac square waves are stepped up in voltage by transformer Ti and converted into pulsating dc by the rectifier. Storage capaci- By John McVeigh, Technical Editor tor C1 charges up through R1 until the voltage across it reaches a few hundred volts. Similarly, C2 charges up to about two-thirds AMPLIFIER/LOUDSPEAKER COUPLING lossy, are smaller than transformers and cost of the ultimate voltage across C1. Q. Can you show examples of transform- less. However, both have.fallen out of vogue, When the capacitors are fully charged and er-, capacitor-, and direct -coupled ampli- at least in middle-of-the-road and high -end trigger switch S2 is closed, SCR1 receives fier output stages? What are the advan- solid-state audio equipment because of a gate drive and begins to conduct. The charge tages and disadvantages of each?- belief that such coupling techniques cause stored in C2 is dumped into the primary of Harold Armistead, Middleton, MA. sonic degradation. Transformer coupling can trigger coil T2. A high -voltage pulse appears result in high -frequency rolloff, and capacitive across the coil's secondary, which ionizes A. The final stages of transformer-, capaci- coupling can cause low -frequency rolloff if the the gas in xenon flash tube FT1. This ionized tor-, and direct -coupled audio amplifiers are design is inadequate. gas provides a low -impedance path for the shown at A, B, and C, respectively. Those Direct coupling is attractive in that nothing charge stored in Cl. As this capacitor dumps +vcc its charge to ground through the flash tube, a large current flows through the ionized gas +vcc and a brilliant burst of light appears. It takes very little time for Cl to completely discharge, so that even though the flash of light generated by the tube is extremely bright, it is

REI also very brief. SPKR SPKR If S2 is kept closed, the SCR will continue to conduct even though C2 has discharged. RE2 This prevents C2 from recharging and thus prevents further excitation of T2 and FT1. For the tube to flash again, S2 must be opened, - C1 and C2 must fully recharge and S2 must --1\7 be closed once more. (Capacitor CI will start to recharge as soon as it has completely discharged and current through FT I drops to zero; .C2 can't recharge until S2 opens.) From your description of the units you purchased, it seems that they operate in essen- -vcc tially the same manner as the circuit just A B C described. To make such a unit blink on and shown at A and B are single -device stages, gets between the final amplifying devices and off, S2 must effectively be closed, reopened, but transformer or capacitor coupling can be the loudspeaker, but involves the added closed again, reopened, etc. This can be used with two -device (push-pull, Class B or expense of a bipolar supply. Also, biasing is accomplished in any one of several ways. For AB) stages as well. Transformer coupling pro- somewhat critical if excessive do offsets at exarnole, an astable multivibrator can be vides two benefits-dc isolation and imped- the output are to be avoided. Finally, if one of used to drive a relay or switching transistor ance coupling. Because the amplified audio the devices in the output totem pole develops wired in parallel with the unit's trigger switch. (ac) signal at the collector of Q is riding on a a collector -to -emitter short, the loudspeaker The multivibrator should be designed to oscil- dc level, the isolation provided by the trans- could be irreparably damaged. late at the desired flash rate and to cause the former is necessary. Impedance transforma- output device (relay or transistor) to close the tion (usually step-down) is less important in TRIGGERING FLASH UNITS trigger loop for only a brief interval. Before transistor circuits than in tube designs, which Q. I recently purchashed some surplus building the additional circuit, measure the tend to have higher output impedances. photographic flash units that I would like to voltage across the trigger switch. Then Capacitive coupling reflects this by providing convert into blinking emergency lights. select a switching component (relay, transis- dc isolation but no transformation. Each unit is powered by two 1 -5 -volt bat- tor, thyristor, etc.) that can withstand this The direct -coupled output stage shown at teries and is triggered by the closure of a voltage on a continuous basis. An IC timer, a C employs transistors 01 and Q2, which are switch. Keeping this switch closed contin- UJT, or even a neon bulb can be employed as driven out of phase, as emitter followers. A uously does not cause the flash to glow or the nucleus of the astable multivibrator. transistor operating as an emitter follower blink continuously. Rather, the flash lights Remember that the interval between trig- has a low output impedance, obviating the upon closure of the switch and then stays ger pulses should be no shorter than the time need for impedance transformation. If a bipo- dark until the switch is subsequently required for recharging of the main storage lar power supply is employed and the transis- opened and closed once more. How can I capacitor. Also, running the flash unit on a tors are correctly biased, the amplifier's adapt this type of flash into a blinking continuous basis calls for the use of alkaline "hot" output terminal (the junction of Re, and warning light? Any information on this sub - or rechargeable NiCd cells. RE2) will have no dc offset. This is so because under quiescent conditions the VcE drops of both transistors are equal in magnitude and opposite in polarity, leaving the output terminal at dc ground. Disadvantages associated with transform- -051 +A er coupling include losses (eddy, hysteresis and winding -resistance), physical bulk, expense and the fact that distortion -producing core saturation occurs if the transformer is driven too hard. Coupling capacitors are not

MAY 1980 83

AmericanRadioHistory.Com paths or modes they can follow. This causes narrow optical pulses to be stretched, and places an upper limit of a few tens of megahertz on Experimenter's the rate at which data can bé sent through the fiber. Graded -index fibers are manufactured to reduce the delay problem associated with step -index fibers. Instead of a well defined core/ cladding interface, this type of fiber merges the core with the cladding to form a gradual change in refractive index. This causes light rays to curve through the fiber as shown in Fig. 2. Because the light near the cladding travels faster than light in the core, there is considerably less pulse broadening. Accordingly, data rates as high as hundreds of megahertz are possible.

Attenuation of Optical Fibers. The first question most people ask when they learn about optical fiber communications is, "How clear are By Forrest M. Mims they?" The answer is incredibly clear. If ocean water were as clear as typical communications -grade glass fiber, it would be possible to see clearly the bottom of the deepest depths of the sea. OPTICAL FIBER COMMUNICATIONS (Part 1) The attenuation of optical fibers is given in decibels per kilometer (dB/km). Inexpensive plastic fibers such as those used to make optical art displays often have an attenuation of hundreds or thou- OPTICAL FIBER communications is one of the fastest growing sands of dB/km, so they're practical only for very short-range com- areas of modern electronics. Here's why. A hair -thin glass fiber can carry more information than 900 pairs of CoRe copper wires comprising a cable as thick as your fist. Glass and plastic fibers are immune to electromagnetic interference and do not attract lightning strokes. Because fibers are insulators and not conductors, they don't generate sparks or present a shock hazard, nor can they be short- circuited. C -RDD/NG F/BE,P Some glass fibers can transmit a modulated beam of light more than ten kilometers before it is necessary to employ a repeater to strength- en the signal. Communications -grade fiber is already cheaper than coaxial cable, Fig. 1. Light rays in ordinary optical fibre take and even greater price advantages are in the offing. The raw material multiple paths causing narrow pulses to be stretched. for glass fiber is sand, but coax is manufactured using copper (for conductors) and petroleum -derived plastic (for the dielectric). Fiber systems are impossible to jam and difficult to intercept. Glass fiber has a higher tensile strength than a steel wire of the same (small) diameter. In this first installment of a two-part series, we'll find out how fibers transmit light and learn something about their idiosyncrasies. In Part 2, _ we'll put fibers to work in some practical systems communication that F/BE,Q--)i you can easily build. /NDE x OF / /pcFRn07/oN PROF/LE How Fibers Transmit Light. Figure 1 shows how a ray of light travels through an optical fiber by making multiple reflections from the Fig. 2. A graded-index fiber is made so that pulse stretching fiber's core/cladding boundary. The core and cladding are both transis considerably less severe, allowing faster data transmission. parent but the index of refraction of the core is slightly higher than that of the cladding. Just as the boundary between air and water is highly reflective, the core/cladding boundary behaves as a mirror to light munications links of a few meters or less. Communications -grade waves striking it within the fiber's acceptance angle. glass fibers have attenuations ranging from approximately 20 to as

The material in Fig. 1 is known as a step -index fiber because of the little as one dB/km! sharply defined transition between its core and cladding. Step -index A 3-dB/km glass fiber one kilometer long attenuates only half the fibers are easily manufactúred, but have one major disadvantage. light injected into one end. In other words, apply one milliwatt of

Light waves entering one end of a fiber at the same time can arrive at radiation into one end of a 1 -km fiber and you'll receive half a milliwatt the opposite end at slightly different times due to the different travel at the other end. Solid-state detectors can work with signal levels of a AIM 65 AIM 65 is fully assembled, tested and warranted. With the addition of a low cost, readily available power supply, it's ready to start working for you..lt has an addressing capability up to 65K bytes, and comes with a user -dedicated 1K or 4K RAM. Thermal Printer Built -In Expansion Capability FullSize Alphanumeric Keyboard TTY and Audio Cassette Interfaces True Alphanumeric Display ROM Resident Advanced Interactive Monitor Proven R6500 Microcomputer System Devices Advanced Interactive Monitor Commands PRICE: $375.00(1K RAM) Plus $4.00 UPS (shipped in U.S. must give street address), $10 parcel post to APO's, FPO's, Alaska, Hawaii, Canada, $25 air mail to Europe, $45 Australia, Japan, etc. We manufacture a complete line of high quality expansion boards. Use reader service card to be added to our mailing list, or U.S. residents send $1.00 (International send $3.00 U.S.) for airmail delivery of our complete catalog. RNB ENTERPRISES i N C O R P O R A T E D

2967 W. Fairmount Avenue Phoenix, AZ 85017 (602) 265-7564

CIRCLE NO.65 ON FREE INFORMATION CARD 84 POPULAR ELECTRONICS

AmericanRadioHistory.Com EXPERIMENTER'S Valtec Corporation Before ordering large reels of fiber, be sure West Boylston, MA 01583 you know exactly what your application is and CORNER how you intend to implement it. You should continued Siecor Optical Cables, Inc. also have spent some time beforehand exper- 631 Miracle Mile imenting with short lengths of fiber to deter- Horseheads, NY 14845 mine if you can work with the material without few tens of nanowatts, so it's possible to extraordinary difficulty, and if it can solve your transmit high -quality data for 10 km or more E.I. Du Pont De Nemours & Co. communications problems better than an ordi- over a 3-dB/km fiber without the need for a Plastic Products and Resins Dept. nary wire link. repeater. Wilmington, DE 19898 It's important to note that optical fibers do not transmit all wavelengths of light equally Quartz Products Corp. Cutting Fibers. You can cut plastic fibers well. Figure 3, for example, graphically shows 688 Somerset Street with a razor blade or hobby knife, but glass the amplitude -versus -wavelength response of Plainfield, NJ 07061' fibers require a more elaborate procedure. two different fibers. Because of the variations in response over a range of wavelengths, it is important to match optical sources with wavelength -compatible fibers. We'll cover the selection of sources and detectors in Part 2 of this series.

.. Drl: Watt : is no

6o energy,. saver: J11011.

\ o The National Aeronautics & 30 Space Administration holds the o ti basic patent.* Their device was ?zo developed to get the highest efficiency possible out of motors which would run on solar energy. 4 EnerCon, under licence from N.A.S.A., developed Dr. Watt to cut WAELENbTN (/irn) the power used by induction motors of 1/2 -hp., or less. The kind that run home Fig. 3. Spectral response of two ITT appliances. Your refrigerator and freezer. communications-grade glass fibers. Your washer and sump pump. The power tools you have in your workshop. Dr. Watt doles out power. The motors in your home don't need all the power they pull all the time. Where to Buy Fiber. More than a dozen companies have entered the optical -fiber For example: Your washing machine's motor runs "full blast", even when field, and communications -grade fiber should you're doing a light load, even when the tub's not turning. It doesn't have soon become available to experimenters for to pull all that power, but it does. Dr. Watt measures the amount of power considerably less than a dollar a meter. In the needed, cuts it down to the minimum, and delivers only that power to the meantime, you can purchase fiber from motor. Edmund Scientific Company (Edscorp Bldg., Barrington, NJ 08007). Their catalog lists Reduce kilowatt hours up to 60%. high -attenuation plastic fibers and 40-dB/km Depending on the function of the motor, you can save from 10% to 60% fibers is silica fiber. Another source for optical of the power it is using now. The motor will run quieter, cooler, and last Math Associates (376 Great Neck Road, longer, too. Great Neck, NY 11021), which sells communi- Dr. cations -grade, low -loss fibers in lengths as Start to save today. Order Watt now. If you're not satisfied, for any short as one meter. reason, return the unit for a full refund. If you have the money and are serious about fiber communications, you can buy Dr. unjacketed fiber in minimum lengths of 500 or Please send me (Number) Watts @$29.95 ea. (Ohio residents add 1000 meters at prices ranging from 50 cents 41/2 % sales tax.) Plus $2.95 postage and handling. $ Total. to $1.00 per meter. Here are some manufac- Enclosed find my check E money order. turers to whom you can write for detailed Bill my VISA or Master Charge,Account# Exp. date specifications, prices and shipping information: Name Or, ITT Electro -Optical Products Division Address 7635 Plantation Rd. Roanoke, VA 24019 City State Zip 41T Corning Or you may order via our TOLL FREE NUMBER: EnErCon Inc. Telecommunication Products Dept. 800-321-3526. Ohio residents call (216) 585-0610. 30044 Lakeland Bouvelard Corning Glass Works 'Licensed from N.A.S.A. Under Patent #4,052,648 Wickliffe, Ohio 44092 Corning, NY 14830 L De12t. E-1 .J CIRCLE NO.25 ON FREE INFORMATION CARD MAY 1980 85

AmericanRadioHistory.Com T.I./M.M.I. 741S240 2708 16K 1024X8 EPRM EXPERIMENTER'S CORNER 174LS241 continued STFTIC 1,1% "74LS24:. $745 74LS24a! M Here's how I cut them. First, I carefully strip off any protective coat- 741S37: R ing(s) with a hobby knife. Some fibers are coated with acetate lacquer S-100 MEMORY 741S374 450ns AMDSGS ADD-ON which can be removed with acetone. (Use acetone only in a well FULLY STATIC OPERATION ventilated s245 '. USES 2114 TYPE STATIC RAMSMS area and avoid contact with skin.) Next, tape one end of the "` .8 VDC INPUT AT LESS THAN 2 AMPS N. RANK SELECT AVAILABLE BY BANK PORT AND fiber to your work surface and pull the exposed portion of the fiber v RANK BYTE over your index finger. Finally, lightly score the fiber over your finger 411 PHANTOM LINE CAPABILITY STOCK ,-. ADDRESSABLE IN 4K BLOCKS IN 4K with a carbide glass cutter while applying a small amount of tension to 16 Kx 1 IWCR EMENTS l" Static a. LED INDICATORS FOR BOARD/BANK the fiber. 74S373 RAM k+ SOLDER MASK ON BOTH SIDES OF BOARD MEMORY All ON FOR THE 74S374 ASSEMBLED $ 5325 TRS-SO OR APPLE II" TESTEL 26900 95 to 450ns . g for S 59 BR/G/,

0 21141 " 2795 1024x4 Static RAMI` T I. HIT... INT. 450 ns 450ns J4 single+5V a000 CLEAVE J I r.r..' P00 -E' CLEAVE S-100 16K ADDO 1 8038C *AsstuiNC L/Cs/T ENTERS VCO Waveform Gen$ BARE BOARD OPPOS/TE END OF FABER' w/slne WITH DOCUMENTATION AND Q DETAILED INSTRUCTION nu2895 Fig. 4. Typical appearances of well and poorly cleaved LOGIC fibers when viewed under 50 -power magnification. 51795 - PROBE' This procedure should result in an almost perfectly flat cleavage KIT 8 plane, but you must confirm this by examining the exposed end of the CONCORD fiber with a 50 -power phono-stylus microscope. Figure 4 shows what you will see when light is passing through the fiber. If the first cut is unsatisfactory, try again. You might even want to experiment with COMPUTER COMPONENTS other methods of cleaving the fiber, such as scoring the fiber while simply pulling on the portion not taped to your work table. 1971 SOUTH STATE COLLEGE . ANAHEIM, CA. 92806 Incidentally, be sure to carefully discard bits of fiber removed during VISAMASTER CHARGE MINIMUM ORDER.S10.00 cutting procedures. Small -diameter fibers can easily penetrate a fin- CHECK OR M.O. (714) 937.0637 ADD 51.50 FOR FRT. ger or a bare foot! NOC.OD. We stock and sell over 12.000 types olsenn-conductors CA L.RES. 000 6%

Attaching Fibers to LEDs and Photodetectors. The two principal CIRCLE NO.13 ON FREE INFORMATION CARD methods of attaching fibers to LEDs and photodetectors are removable connectors and fiber pigtails. Removable connectors are expensive, but AMP, Inc. (Harrisburg, PA 17105) has introduced a moder- YOU CAN TAKE IT WITH YOU! . ately priced connector which is finding widespread popularity. This connector will probably become available to experimenters in the near Quality Sound takes future. Laser diodes and LEDs with factory -installed fiber pigtails cost to the road ... the sky .. . hundreds of dollars. Motorola's solution to this problem is a new and the ocean! series of emitters and detectors with integral light pipes which mate with AMP connectors. One of the emitters (MFOD402F) includes a built-in integrated preamplifier. For more information, you can request data sheets for the MFOE102F LED and the MFOD102F and MFOD302F detectors from Motorola (P.O. Box 20912, Phoenix, AZ 85036). Although I've found AMP connectors the best solution for coupling

fibers to LEDs and detectors, I often attach fibers directly to epoxy - encapsulated LEDs. The easiest way to do this is to heat a small awl in a flame and push its hot point through the epoxy all the way to the MK I & IIB semiconductor chip that emitsthe light. You should then test the LED to make sure it has not been damaged and that a bright point of light is visible at the exposed surface of the chip. LAB For temporary experiments, you can anchor a fiber in the hole using PCIE52,A MSERIES cyanoacrylate adhesive such as Eastman 910. For more permanence, insert the LED in a short length of heat -shrinkable tubing, insert the We wrote the book on miniature speakers, from Design to fiber into the LED (making sure the end has Production! Our five models speak for themselves in total been cleaved properly) and surround performance, styling, and features that are found in no other the LED and fiber with epoxy. You'll need to hold speakers... such as, Solid Walnut Cabinetry, full 12 db cross- everything together with tape, clothespins or clamps until the epoxy over network, a specially designed cone with our exclusive hardens. rubber surround, and a deep throw speaker basket, These For best results, pulse -modulate the LED and monitor the amplitude are just a few of the reasons why our Bass is unequaled in the of the signal emerging from the opposite end of the fiber while slightly Industry. "Dimension Minis' are Proven best by listening test." moving the end being cemented to the LED until maximum signal is Come in for a demonstration and judge for yourself. received. This procedure is very much like tweaking the catwhisker in See and Hear the New Dimension in Sound at an old-fashioned crystal radio. Your Local Stereo Dealer. Because LEDs can also function as detectors, you cari reverse this procedure as long as the source LED is made from the same type of semiconductor material as the receiver LED. Figure 5 shows a trans- MILIWooffl mitter and receiver circuit you can use to align the fiber. 819 S. Kraemer Placentia, CA 92670 The procedure outlined above works, best with GaAsP red LEDs (714) 630-5440 encapsulated in clear epoxy. The 650-nm wavelength emitted by - Representative and Dealer Inquiries Welcome these diodes transmits well through most glass and plastic fibers, and

POPULAR ELECTRONICS CIRCLE NO.15 ON FREE INFORMATION CARD

AmericanRadioHistory.Com Fig. 5. Schematic diagram (left) of .- FIBER LED transmitter and receiver to be fibers. 4-9V used for aligning spliced glass +, N l ,Q/ /p.F /op II 7 F

RZ /K

/DENT/GAL LEDS

OUTPUT To SCOPE .4M PL/P/EP Fig. 6. One way (below) of mating a glass TONE TRANSM/7/ER TONE RECE /VE R OR PNONES .fiber to a common light -emitting diode. R/- FREOuENey ,4DvsT RC -So cE0

PRE -1 DIGITAL. LOGIC PROBE

Compatible with DTL, TTL, CM'JS, MOS and Microprocessors using a 4 to 15V powe'r supply. Thresholds automatically programmed.' Automatic resetting memory. No adjustment required. Visual, indication of logic levels, using LED's to .show high, lore, bad level or open circuit Iogit and pulses. Highly sophisticated, sidrt pocket portable Cprotective'tip cap

and removable coil 'cord). :

DC to>50MHZ 10 Nsec. pulse response.f

120 K St impedance ° Automatic pulse stretch- to M sec. ing 50 * ADD $2.00 FOR SHIPPING Automatic resetting memory (N. Y. CITY,ANO STATE' RESIDENTS ADD TAX) Open circuit détection Automatic threshold resetting Compatible with all logic - families 4-15 VDC Range extended to'15-25 VDC. with optional PA -1' adapter :-=- Supply O.V.P. to ± 70 VDC No switches/no calibration.

OK MACHINE .& TOOL.CORPORATION 3455 Conner St., Bronx, N.Y. 113475 .(212) 994-6600 / Telex 12509i i CIRCLE NO.49 ON FREE INFORMATION CARD MAY 1980 87

AmericanRadioHistory.Com //// 1111//5""":1/J/ILa\\ dE,y1\r ,M. -..i DX ~tn~ Listening

By Glenn Hauser WIDER BANDS FOR SHORTWAVE BROADCASTING

DESPITE pessimistic early reports, just 6029 kHz, with a Spanish broadcast including before it adjourned the World Administra- "Horizontes de Hielo" at 0000-0200 GMT tive Radio Conference in Geneva approved said to be coming from Argentina's Esperanza substantial expansion of the international Army Base at the northern tip of Palmer NOW-the best shortwave broadcasting bands. The expan- Peninsula. Though the power was given as sion more or less legitimizes longstanding only one kilowatt, the station, named for the in Electronics out -of -band operations, which certain coun- patron saint of communications weapons, training tries have carried out under a regulatory loop- could be heard almost every evening in North can hole. Crowding on the 6 -MHz band and the America except during the peak of the south- cost you less- awful mixture of ham and broadcasting on 7 ern summer when there was too much day- MHz were not resolved, but higher up it was a light on the path. Ironically, in November, No school, large or small, gives you better different story. Here are the new band limits: AFRTS-Washington made a regular seasonal electronics training than E.T.I. Nor, at a 9500-9900, 11650-12050, 13600-13800 (a expansion of its broadcasting hours to fairer price. Compare quality, price, ser- completely new band), 15100-15600, Antarctica, on 6030, resulting in the wiping out vice, background. ETI has been training 17550-17900, 21450-21850, 25670-26100 of reception of LRA-36 in North and South men & women for entry into or advance- kHz (the last, a slight loss in a grossly under- America after 0045 GMT. ment in electronics since 1909, utilizing utilized band). Argentina made the most of the propagan- educational techniques of RCA and Syl- vania. Only ETI combines Autotext pro- Canada has also reserved 3950-4000 kHz da value of LRA-36, claiming that it was fur- grammed learning, "listen & learn" cas- for domestic broadcasting and 7300-7400 ther confirmation of Argentina's sovereignty settes and "hands-on" projects designed for external broadcasting. The AM band also over a sizable hunk of Antarctica (which is for learning at home, quickly, easily. Wide expands, in steps, up to 1705 kHz by 1990. supposed to be an "international continent"). course choice. The new shortwave broadcast bands do not It was also billed as the world's southernmost officially take effect until 1989 (except 9 MHz, radio station, conveniently ignoring AFAN at in 1985), to allow present fixed service occu- the U.S. McMurdo Base. For once, Argentina pants plenty of time to move. However, you rather than the U.S. can be accused of neo- can be sure many countries will jump the gun colonialism. in order to establish squatter's rightson new =-i--_ frequencies. This should help alleviate over- Australia. Once it was OK for people in Chi- crowding on the present bands. na to write letters abroad, Radio Australia

,- -_ - _ --(_ - s ,'. - _ was inundated with mail from China - Afghanistan. In August 1979, long before it 130,000 by the end of 1979. This avalanche invaded Afghanistan, the USSR began broad- persuaded the authorities to give the go- SEND TODAY for all new FREE catalog casting Radio Afghanistan domestic pro- ahead to the reconstruction of the Darwin or for faster service, use the toll free tele- grams from three sites in the Soviet Union. As transmitter site, which was destroyed by a phone number below, day or night. No always, no public announcement was made cyclone several years ago. Darwin would put obligation-no salesmen will call. about this, leaving it to the BBC Monitoring an even better signal into China so the station Service and other astute monitors, such as could begin teaching GY ' the Chinese to speak Victor Goonetilleke in Lanka, NHSC Sri to make the Strine (Australian English). Though it obvious- ELECTRONICS TECHNICAL INSTITUTE proper deductions. However, for the March ly lacked the staff to manage its Listeners' FOUNDED 1909 and April broadcasting season, USSR regis- Club, it was not until this year that Radio 11.1 153 W. Mulberry St., Dept. 10050 trations filed with International Australia '"o,,E sr,er Lancaster, Ohio 43130 the Telecom- disbanded it, and instituted a new . ... _ . munication Union do show three of the four QSL policy, restricting their availability to one . FOR. FASTER SERVICE - frequencies as targeted on Afghanistan or month per year, instead of encouraging floods TELEPHONE FREE 24 HRS A DAY neighboring countries. At last report, these of useless reception reports. 1 800 621 5809 relays were on 7235 and 6190 kHz in the local Illinois residents - 800 972 5858° mornings; listen at 0125 GMT for tone bursts Belize. The 20 -kilowatt Radio Belize trans- typical of Soviet transmitter tuneups, and at mitter on 834 kHz has long had a mixed 0130 for programming. However, during the reception in the U.S. WCCO and WHAS, and ETI Home Study, Dept. 10050 153 W. Mulberry, Lancaster, Ohio 43130 summer, higher frequencies are likely to be their listeners, don't like the heterodyne it used, 11710 15305. Please rush FREE catalog on electronics oppor- perhaps or These chan- causes to their adjacent frequencies; DX lis- tunities, and training. I'm interested in nels have been fed by a frequency known to teners who can pull it past these two giants Basic O Career Specialized be in the "Afghan SSR," 6230 kHz. Both this welcome a bit of exotica on the AM dial. But Advanced frequency and 4775 could be monitored in its days may be numbered. If 9 -kHz spacing is NO SALESMAN IS TO ME, CALL ON EVER. North America around sunrise. Radio Afghani- adopted for the Americas, this "split" could stan's only two English broadcasts (see April be lost. Also, a QSL received by National Name POPULAR ELECTRONICS) remained very difficult Radio Club member Lance Sang revealed to pick up. The next country to be relayed that the station is phasing out AM in favor of Address from the USSR might want to reconsider the an FM network. But that would introduce

consequences. . . . some interesting new DX targets. Sporadic E City/state/zip could bounce as far inland as Amarillo, St. iOhio______Registration NO. 0683H Antarctica. Radio Nacional Arcángel San Louis and Roanoke, while reception along the CIRCLE NO.24 ON FREE INFORMATION CARD Gabriel suddenly appeared last October on Gulf Coast would be relatively common. (Continued on page 90) 88

AmericanRadioHistory.Com = G -

Expand your knowledge Subscribe to

The 1980's are here! The decade of - graphics, word processing, computer - the personal computer has arrived, and music, speech synthesizers, simulations, BYTE has made it happen! BYTE - robotics, personal data base manage- the small systems journal devotedto ment, business computing - and personal computers - has helped usher hundreds of other fascinating hardware in the new era. Leading the personal and software applications. - computer revolution, which is already - Resolve now to expand your transforming home and personal lite, are computer knowledge. Subscribe to BYTE! BYTE's_.160,000 enthusiastic readers. Their enthusiasm has made BYTE the largest computer magazine in the world!

To be knowledgeable in the 1980's Fill in and marl the coupon today. Read your Ilrsr copy nl BVTL:II Call us toll -free is e.wynhing you expected. honor ur Irvnice. N It isn't, lust uae you need to know how to use personal "Cancel" on the Invoice and mail It bank You won't be billet and the firs) issue k yours al no charge. computers. BYTE'is your personal 800-258-5485 guide to the new era. BYTE tells you r BYTE Subscription Dept. P.O. Box 590 Martinsville, NJ 08836 1 how to build, buy, and use computers Please enter my subscription for: for fun, practical purposes, and profit. 1 1 One year $18 (12 issues) Two years $32 Three years $46 r'S1 With help from BYTE, you can experi- 1 Check enclosed entitl6 me to 13 issues for price of 12 (North America only) ment right in your own home with I 1 Bil Visa Bill Master Charge Bill me (North Amen only) sl I P I Card Number Expiration °' I Ásl I Signature Name (please print) ól 1 Address 1 10 the small systems journal City Stare/Province/Country Code I ÑI A McGRAW-HILL PUBLICATION I Foreign Rates (To exped re service, please remit in U.S Funds! O Canada or Mexi© One year $20 OTwo years $36 Q Three years $52 I 1 Enrope, one year (air delivered) $32 1 I All other countries, one year (surface delivered) $3Z Air delivery available on request. 7350 I. i © BYTE Publications. Inc 1980

CIRCLE NO.8OP1 FREE INFORMATION CARD MAY 1980 89

AmericanRadioHistory.Com BIG 21/2"7" ,: AMA ZING DX LISTENING continued :S 9:9 China. It had to happen. On Jan. 1, Radio DISPLAY ,j . SCIENTIFIC -and ELECTRONIC Peking's domestic program began carrying SOLID STATE DEVICES ads (for foreign merchandise only) to the tune CLOCK/CALENDAR KIT ALL NEW AMAZING DEVICES NOW AVAILABLE IN of 70 minutes a day. The cost is $693 per CONSTRUCTION PLANS, KITS OR COMPLETED ITEMS. minute, and those interested should call 0101 Displays time of day, date or alternates All plans Include itemized parts lists with given sources. between both automatically. May be connected to 868581, ext. 2522, or cable 0731. Peking's 8 ohm speaker for alarm clock. Operates from 120 lead was followed by regional stations VAC 60 Hz. LASERS -CONSTRUCTION PLANS such $49.95 Oak case extra, $29.95 #5SL1 - POCKET SOLID STATE 9000A 59.00 as Heilongjiang. #LPH2 - POCKET VISIBLE RED OPTICAL VERSION ... S8.00 #9081 - RUBY/YAG RAY GUN 515.00 Costa Rica. A station which figured in our UNIVERSAL w ` #LC1 - CO2 BURNING, CUTTING 515.00 "Revolution by Radio" article about Radio Iv k #LBT1 - LIGHT BEAM COMMUNICATORS -I mile S10.00 DESIGNER Sandino in POPULAR ELECTRONICS last Novem- fook KIT 6100 ULTRASONICS -CONSTRUCTION PLANS Ler, Radió Noticias del Continente, has Indispensable aid to aPF1 - PHASOR PAIN FIELD 515.00 become a cause celebre. Its leftist program- digital IC design. 2 OPSP1 - PHASOR SHOCK WAVE PISTOL $5.00 ming aimed at military dictatorships in South pushbuttons, 2 readouts, AIPG1 - INVISIBLE PAIN FIELD GENERATOR 0.00 4 8 LEDs, America brought strong official protests from switch outputs, f AHT9 ULTRASONIC LISTENING DEVICE 510.00 - Argentina, 2 generators, 1M® while Costa Rican authorities hem- :eP °I0" 5V 2counters, med and hawed about what do it. It $49.95 SCIENTIFIC -CONSTRUCTION PLANS to about 7,10 supply pins. appears Breadboard extra. $59.95 assembled #BTC3 - 250Kv HIGH FREQUENCY TESLA COIL 59.00 that the nominal "owner," Ana Lor- #TC4 - 1.5 Million Volt HIGH FRED. TESLA COIL ... S12.00 ena Carlin Leiva, a 29 -year -old chemistry stu- s , 1 6101 Digital LogicCourse$29.95 ~ #10G1 - ION, PLASMA & FORCE FIELD Generators .... S8.00 dent, would hardly have the resources to run ASK FOR OUR FREE 8.PAGE CATALOG such an operation, according to an exposé by SECURITY & PERSONNEL DEFENSE CONSTRUCTION PLANS Argentiriian Roberto H. Iglesias in the Review =TASAR - INFO & PURCHASE PACK -Elect. Dart gun ... S1O.00 P/4CCOM of International Broadcasting. She does hap- #&HG4 - SHOCK GUN SR.00 mVWPMS - VOICE ACTIVATED Wireless Phone Monitor .. 510.00 pen to have been the secretary of a former 14905 N.E. 40th. Redmond, WA 98052 12061 883-9200 #FBT7 - LONG RANGE WIRELESS MIKE S' 00 owner, Francisco Aguilar Bulgarelli, whom a O 0101 SOLID STATE CLOCK CALENDAR KIT 5 49.95 RSNP2 SNOOPER PHONE LISTENING DEVICE 57.00 rival Costa 0 0101 OAK CASE FOR ABOVE 29.95 - Rican broadcaster labels as "a MOVEMENT MOTION 510.00 O 6100 UNIVERSAL DESIGNER KIT 49.95 #MMD1 - AND DETECTOR political friend of Kim II Sung." Though sup- 6100 ASSEMBLED DESIGNER KIT 59.95 O OT 595 BREADBOARD 11.00 posedly a "commercial enterprise with noth- For a more complete listing of over 500 different plots, kits and com- OT 59B BREADBOARD 2.50 ing to hide," no ads were 6101 DIGITAL LOGIC COURSE 29.95 pleted products in the fields of LASERS, INFRASONICS, ULTRA. carried for many ADD 52.50 PER ORDER POSTAGE AND HANDLING. SONICS, NUCLEAR, HIGH ENERGY, FORCE FIELD, PLASMA, months until some trade -outs appeared with a NAME ION, CHEMICAL, ELECTRONIC and SCIENTIFIC PERSONNEL few leftist publicationspublications and businesses. At PROTECTION, SECURITY and SAFETY DEVICES, send 51. for our ADDRESS last check, was still plugging away on catalog to: 9615 kilohertz, throughout CITY. ST. ZIP most of the day VISA INFORMATION UNLIMITED, INC and night. CARD NO MSTR CMG Dept 01, P.O. Box 716 SIGNATURE P5 I. Amherst, N.H. 03031. Cuba. During a Christmas visit to Radio Habana, we wondered why they weren't CIRCLE NO.52 ON FREE INFORMATION CARD CIRCLE NO.34 ON FREE INFORMATION CARD broadcasting in English on mediumwave, which could cover much of the US, and reach Even after 100 plays an entirely different, and presumably larger audience than on shortwave. Less than a month later, The Voice of Cuba began a night- your records ly 6 -hour block of English uFES, I (replacing Spanish) on 600 kHz. The programs, which begin at ; "ea ,e 4kIS 4 ¡ will sound midnight Cuban time (EST/EDT) are similar or f identical to those carried at other times from Radio Habana on shortwave. And a month BETTER after that, the same transmitter began carrying Radio Moscow in English all evening long THAN and after 6 a.m., giving Americans for the first NEW time the opportunity of hearing Radio Moscow on ordinary AM radios. with Lifesaver! In the U.S., because of our relative isolation from other countries, we don't think of the AM Introducing LIFESAVERTM, the multi- band as suitable for international broadcast- purpose record treatment from ing, but now the Cubans are proving that it is. Audio-Technica. It's a long-term However, the Voice of America for many antistatic agent which lasts 100 years has been beaming a powerful signal plays or more. And a record preserva-" into Cuba on 1 180 kHz from the Florida Keys. tive which protects against environmental `'- ` " e.- LIFESAVER LS -I Turnabout is fair play. But one thing isn't fair: attack and improves the effectiveness of any with DiscProtecr' formula Cuba jams the VOA. By the way, you'll find wet or dry record cleaner. Treats 60 sides. 512.95 Radio Habana on the top floor of the Radio But LIFESAVER with DiscProtecTM formula is also a dry lubricant which sharply reduces record - Progreso building. But don't bother looking for stylus friction. Tests* prove lower harmonic distortion from a disc treated with LIFESAVER signs -there aren't any. after 100 plays than from the first play identical of an untreated record! We also discovered that Habana has three Your records will sound cleaner and quieter from the very first play with LIFESAVER. And 50 or active FM stations, Radio Progreso on 92.1; even 100 plays later they'll still sound better than new. Just one easy application protects your Radio Musical Nacional, CMBF (classical) on library for years. about 93.75; and with a stronger signal, Radio Enciclopedia, which seemed Enjoy better sound today and tomorrow with LIFESAVER! See dramatic proof at your slightly above and in Audio-Technica dealer today. Audio-Technica U.S., Inc., 33 Shiawassee Avenue, Dept. 50P, 94.9 identifies as stereo on "95". This Fairlawn, Ohio 44313. In Canada: Audio Specialists, Inc., Montreal, P.Q. station, with its easy -listening music and brief informative talks, is heard throughout Habana in public areas, and makes an interesting DX target during tropospheric or sporadic E From independent lab tests reported by Lets openings. The ultimate Cuban FM DX would © Feldman in Audio Magazine, 1980. audio technica February, be to pull in the music -only transmitter serving C) INNOVATION 0 PRECISION 0 INTEGRITY Write for your Gee reprint. the Varadero Beach resort hotels on 98.4

90 POPULAR ELECTRONICS

AmericanRadioHistory.Com MHz. Spotty reception there indicates its power is oh the order of a few watts. We were not invited to visit the Radio Mos- cow transmitter near Habana (dealt with in this column last August), and indeed for months Radio Moscow would not acknowl- edge that it existed. But last winter, Moscow began to register the appropriate frequencies as coming from Cuba. This opened the door last January for Kevin Mikell to receive the first Radio Moscow QSL reported to bear a "via Habana" endorsement. During our visit, Cuba moved a Habana All These station from 790 to 1 140 kHz, more effectively blocking reception of the Miami Cuban station -on -Sight Money Makers WOBA. Meanwhile, anti -Castro elements in Sell Florida have become more active in clandestine shortwave broadcasts varying around Can be Made with just One Tool!* 7080 kHz several evenings per week before and after 9 p.m. local time. Harry Helms Picture yourself turning out hand practice, you'll find yourself chang- reports that two formerly separate opera- sell- ing operations from set-up to set-up tions, Radio Abdala and Comandante David's crafted things like these - and Radio Libertad Cubana, now coordinate ing them for a profit! in less than 90 seconds. transmissions and share facilities. The It's easier than you think. You can chances that they are actually broadcasting What's more, you'll be able to "bor- from "a small piece of free territory in the enjoy hours of pleasure and relaxa- tion making beautiful, useful items row" functions and set-ups from Oriente mountains" of Cuba are rather one tool to enhance the capabilities remote. In February, the FCC cracked down from salad bowls to lamp bases. the tools. And you can add on Cuban clandestine broadcasts from Miami, Then, as a bonus reward from your of other busting a station called Radio Giron, which functions later leisure, you can see these things sell accessory tools and was not familiar to DX listeners. Mark V as fast as you make them. as you need them. So your - can grow right along with your Ecuador. HCJB has been experimenting with a 100 -watt transmitter, 24 hours a day on You may have thought it takes too woodworking business .. . 26020 kHz. Results have been remarkable. much costly equipment to turn out It's heard regularly in Europe and North Amer- this kind of professional -looking Send for your FREE information.. ica; and Arthur Cushen reports that reception work. But you're wrong. You no when it's midnight in in New Zealand peaks longer need to spend a fortune or Ecuador. This is further evidence that most Mail the coupon today. We'll send clutter your limited workshop space countries have been missing the boat by you all the information on the amaz- ignoring the wide-open 11 -meter band during with dozens of cumbersome tools. V. the solar cycle peak. Meanwhile, HCJB con- ing 5 -in -1 tool - the Mark The tinues its project to homebuild a mammoth Now, there is one unique power tool information is absolutely free and 500,000 -watt transmitter. To avoid influencing so versatile, so high in quality, and without obligation. We'll also tell reception reports, they plan to put it on the air so easy to use that it's all you need to you how you can actually use the without announcing for tests later this year create instant best sellers. amazing Mark V in your own home the frequencies and the precise times that it without risking a single penny. is being used. This remarkable machine is the 412 Shopsmith Mark V. It is so amaz- Transkei. On Dec. 26, Capital Radio went on the air from this "homeland" in South Africa. ingly compact that it takes no more Patterned after its London namesake, it's not space than a bicycle. But it out- for the blacks of Transkei, but is a private performs any combination of power commercial outlet for South Africa. This area tools you can buy. has been an extremely difficult one to DX in North America on mediumwave, because The Shopsmith Mark V actually South Africa's very few AM stations have a brings you all five of the most im- 5 kilowatts. But Capital Radio power of only portant power shop tools you need The tool to start with ... has 500 kW on 603 kHz which ought to make the system you grow with! it to North America easily when conditions are -a 10" table saw, 12" disc sander, favorable; North American 50 -kW stations are horizontal boring machine, 161/2" 'Somef,and tool work will be necessary regularly heard in South Africa. The time to variable speed drill press, and 34" Start checking 603 is at the 0300 GMT sign - lathe in one complete free-standing on (0400 on Saturdays and Sundays). But - Shopsmith Inc. floor unit. Capital Radio is also on shortwave, the better Dept. 2388 to serve Cape Town, initially with 10 kW, but 750 Center Drive to be raised to 50 and then 100. The morning Each tool is powered by the same Vandalia, Ohio 45377 frequency was 3950, but this may be rugged heavy duty, precision -built Infor- changed seasonally. motor so the Mark V costs you far Yes! Please mail me your FREE mation Kit on the Shopsmith Mark V. I less five individual tools. understand there is no obligation. U.S.A. Meanwhile, the shortwave scene in than this country is becoming less stagnant. A New Orleans FM rocker, WRNO, has applied for It's easy to make sell -on -sight Name shortwave, to beam 100 kW of rock and net- items with the one tool that's right Address work news northeastward toward Europe. The for all your jobs! The Shopsmith North Dakota Farmers Union is considering Mark V is versatile and easy to City a station. The World applying for shortwave State Zip Christian Broadcasting Corp. has bought land operate. After only about an hour's

MAY 1980 CIRCLE NO.66 ON FREE INFORMATION CARD 91

AmericanRadioHistory.Com on Alaska's Kenai Peninsula where they hope to install a 250 -kW shortwave transmitter. ON THE CUTTING ED Ng.... WYFR has abandoned its old Scituate, Mass. site, where even the towers have come L. down. Installations continue at the new Family Radio site near Okeechobee, Florida. The goal is a total of 10 transmitters. Another microcomputi language, Italian, has been added; coming soon are a 24 -hour "eastern Canada" service 4.7 also audible in the USA and a broadcast to Cuba requiring a new high -angle antenna. The Voice of America had no broadcasts in The .-..magazine today 'St biggest selling Persian until last year. It took the hostage for crisis for VOA to be able to multiply its pro- Microcomputer. Innovative: and informative, grams for Iran and other critical countries in 80.Microcómputing is full of programs, appli- the Middle East. VOA is so inadequately funded that only a crisis will generate the cations and valuable reviews of software and° necessary government concern. Meanwhile, hardware that will save you money. Subscribe: VOA does not bother to broadcast to such

. . ti 'safe' areas as France, Germany, Italy, Spain, Japan in their own languages. If one of these countries were to become hostile to the U.S., then the VOA would consider talking to them as well.

Enclosed is: $15 for 1 year $36 for 3 years Bill me U.S.S.R. Though Radio MoscoWs "news" is. supposed to be live on the World Service, if Name not on the overnight North American Service, Address all its programming suffers from a lack of spontaneity. But twice a year, Radio Moscow City State Zip broadcasts a live event-coverage of the big military parades in Red Square, on Nov. 7, the Canada: SIC per year US funds; other foreign: $26 per year US funds. Please allow 6-8 weeks for delivery. anniversary of the October Revolution, and on May Day. While you won't hear any specula- 80 Microcomputing / POB 981 / Farmingdale NY 11737 tion from this source on the latest pecking 705BP order in the Soviet leadership implied by the positioning of dignitaries, nor any commentary CIRCLE NO.23 ON FREE INFORMATION CARD on Soviet military capability beyond the official line, this kind of broadcast is still a novel-

ty on Radio Moscow. I heard it last November, --PARTS MASTERS and had a real sense of being there, as Gen. Ustinov and his troops hollered greetings STOCKING, DISTRIBUTOR back and forth across the square. Frequen- SAVE! cies aren't known much in advance, but may be announced during the preceding few MONEY TIME FREIGHT days; or if you scan the bands shortly before 0700 QUALITY STEREO EQUIPMENT ° GMT on May 1, you should find this live cov- AT LOWEST PRICES. erage on separate frequencies in English, YOUR REQUEST FOR QUOTA- Russian, and perhaps even Chinese. TION RETURNED SAME DAY. By the way, even before the threat of Olym- pic boycotting arose, Radio Moscow was Ihr FACTORY SEALED CARTONS- making no promises that it would air any sig- . 10 MHZ DUAL TRACE GUARANTEED AND INSURED. nificant Olympic coverage, since it was it OSCILLOSCOPE SAVE ON NAME BRANDS LIKE: I assumed that could be seen throughout the world on color TV. MODEL -302 LEADER PIONEER SANSUI KENWOOD DYNACO Sensitivity calibrated Publications. An Alternative Programming Bandwidth DC or 2Hz to 10MHz SHURE SONY Strategy for International Radio Broadcasting, by Kim Andrew Elliott, is a major new work in a Time Base Calibrated: 1µS to 0.2S per div; MARANTZ KOSS neglected field. It examines the effectiveness AND MORE THAN 50 OTHERS of the "traditional programming approach" BUY THE MODERN WAY we are all familiar with, compared to an "al- dillS,ly BY MAIL-FROM ternative programming approach" exemplified by Rudy Espinal and "This is Santo Dom- ingo." The 196 -page PhD. thesis is available in print or microfilm via University Microfilms (inquire at any large library). 31/2 DIGIT LAB DMM Information Sheet. This free list is all you MODEL B & K 2830 need to become an "insider" in shortwave listening and DXing, not for the information it 0.5% DC Accuracy contains, but because it refers you to many Autozeroing illina'v audio of information. It's for a 100µV, 100 nA, .01 ohm resolution BANK CARDS ACCEPTED other sources yours self-addressed stamped envelope (from 12 East Delaware abroad, mint stamps equivalent to 31c are PARTS MASTERS, INC. Chicago, Illinois 60611 accepted; 17c in. Canada), to Glenn Hauser, P.O. Pinebrook, N.J. Box 684 07058 312-664-0020 University Radio WUOT, Knoxville, TN 37916. (201) 227-7797 We cannot promise a personal reply to specific questions. . Send for fú11 catalog CIRCLE NO.33 ON FREE INFORMATION CARD POPULAR ELECTRONICS CIRCLE NO.55 ON FREE INFORMATION CARD

AmericanRadioHistory.Com REVERSE 1C-$0 CKET Home-brew adapter simplifies BY GENE NELSON, correcting mirror -image wiring errors

are that many' of you terconnected ("incorrect" pir 1 to cor- ing of the socket adapter and socket, the

have'hadCHANCES the following experience.. ;rect pin 1, etc.) with short lengths of'in- - author used wire having red insulation An experimenter builds a complicated sulated hookup wire. for one set of eight pins and wire with analog or digital circuit using printed cir- A 16 -pin DIP socket adapter, such as black insulation for the other set. He also cuit techniques, even thoughtfully in- Cambion Model 3728-01-03-00 can be reccrimends the use of tweezers and a stalling sockets 'for the integrated cir- used, or one can be made from á small soldering iron with a fine tip.. cuits. But he wires the project -for ,,the piece of perforated board whose holes Be sure to -check for' inadvertent mirror image of the proper IC pinouts! are 0.1 inch (2.5 mm) apart and 16 Vec- shorts caused by touching conductors, This error can be caused by mistakenly tor type T-44 pins., A length of hookup' =solder bridges, etc. The socket/socket laying out the bottom of the board using wire is soldered to each socket adapter adapter combination can then be made a top -view pinout. It can also occur if the pin'. The author -wanted to keep his .Re- one rigid assembly by cementing small negative is inadvertently flippedbefore verse Sockets as compact as possible, plastic sheets to the sides of the socket. the etching process is begun. so he used 0.5 -inch (1.3 -cm). lengths of and socket adapter. , Faced with this problem, the unfortu- Kynar insulated No. 30 wire with 0.1 inch

nate experimenter has heretofore had (2.5 mm) of insulation ,removed from c . Use. The author's completed Reverse only a few Options; as follows. Discard _each end. Kynar insulation was found to Socket adds 5/e inch (1.6 cm) to the

the board ;and start from scratch; re- be preferable to PVC plastic because of . height of the -IC with respect to the sur-

move the IC, unsolder the, socket, and its greater,tolerance to heat. _- face of the printed circuit board._ In most Solder the IC to the bottom of the board; or, leave the IC and socket in place but ERRONEOUS PINOUT CORRECT PINOUT carefully cut the necessary foils and compensate for the inversion by soldering insulated jumper wires. The "Reverse Socket" described here provides the experimenter with a much When incorrect pinóut is transposed about simpler solution. It's a home-brew sock- the centerline, correct pinout is obtained.. et adapter which inverts. the mirror ím-,. age again, thereby cancelling out the er- When removing the insulation, take cases, there will be sufficient clearance ror. An easily and inexpensively con-,. care not to nick the wire. Tin all surfaces - between the board and the top of the en- structed project, the Reverse Socket before. soldering. A "third hand") will closure to accommodate the adapter. In can be assembled using a DIP IC socket make the task of soldering much easier: particularly 'crowded enclosures, how-

and commercial socket adapter or a-, The "hand" can be either a commercial - ever, the height of the pc board spacers ' small piece of perforated board. and pivoting vise or a miniclip attached to might have to be reduced accordingly. Vector type T-44 pins.- If the inverted one end of a length of No. 1.4 copper This same basic idea can be used board contains more than one DIP IC, wire, the other end of whichris secured with any size or shape of IC socket, as- as many Reverse Sockets as are need- to the.work surface. suming that an appropriate socket ed can be built. Place pieces of' 1/16 -inch (1.6 -mm) adapter can be purchased or home diameter heat -shrinkable tubing 3/16 brewed. Other types of foil layout errors Construction. The illustration reveals inch (4.8 .mm) long over each socket ,; can -be corrected by interconnecting the that if the incorrect pinout is transposed adapter pin to prevent shorting. Next, socket and adapter to cancel them. about the center'line,,.the correct pinout bend the, leads of a low -profile IC socket Naturally, one should make sure the ís obtained. Accordingly, the Reverse 45 degrees toward the center line of the board will be etched correctly before the Socket is constructed by mounting a - socket and solder the free end of each process 'is begun. But should anyone "correct pinout" socket above an "er- jumper` to the appropriate piit. To elimi- unwittingly make such a mistake, this is roneous pinout".socket adapter, bothjn- nate confusion during the crossover wir- an easy way to correct the error.

CLEAR -CHANNEL AM STANDARD BROADCAST STATI ONS Courtesy of General Electric Co.

Frequency Class I - A Assignment 760 WJR, Detroit, MI 1020 KDKA, Pittsburgh, PA (kHz) 770 WABC, New York, NY 1030 WBZ, Boston, MA 640 KFI, Los Angeles, CA 780 WBBM, Chicago, IL 1040 WHO, Des Moines, 10 650 WMS, Nashville, TN 820 WBAP, Forth Worth, TX 1100 WWWE, Cleveland, OH 660 WNBC, New York, NY 830 WCCO, Minneapolis, MN 1120 KMOX, St. Louis, MO 670 WMAQ, Chicago, IL 840 WHAS, Louisville, KY 1160 KSL, Salt Lake City, UT 700 WLW, Cincinnati, OH 870 WWL, New Orleans, LA 1180 WHAM, Rochester, NY 720 WGN, Chicago, IL 880 WCBS, New York, NY 1200 WOAI, San Antonio, TX 750 WSB, Atlanta, GA 890 WLS, Chicago, IL 1210 WCAU, Philadelphia, PA

POPULAR ELECTRONICS 93

AmericanRadioHistory.Com THIN SOLAR Computer Bits 12/24 -Hour Quartz Alarm .., Chronograph

Now with fashionably thin styling, long-lasting solar power, 12- or 24 -hour selection, alarm and full chronograph.

Featuring: By Hal Chamberlin Famous Quartz Accuracy to 2,5 Seconds a Month ELECTRICAL NOISE Thinnest Solar Alarm Built-in Electronic Calendar Chronograph Available Night Light for Evening Viewing at This Low Price! Constant LCD Display Day of the Week Indicator Easily Adjusted "Snap" Type ELECTRICAL noise is a major problem in While the foregoing sources are responsi- $4488 Bracelet home computers. Generated within a ble for occasional high -amplitude spikes on Solar Power is now combined with remarkably thin styling and computer itself, it can, in many cases, inter- the power line, universal motors (those with famous quartz accuracy in our best selling 1224 -Hour Alarm Chronograph. A combination that Seiko and Citizen can't match. fere with nearby radio and TV reception and brushes) and lamp dimmers generate lower - even at $200 more! even with the computer's own operation! amplitude, but more continuous, noise. The Many See the value you get for only $44.88 unexplained home -computer malfunc- obvious source of noise in universal motors tions can, in fact, be traced to external noise. originates with armature brushes that con- 24 -Hour Alarm-Pleasant, but effective, alarm can be preset Since are usually more for any minute of day or night. Constantly read indicator lets you microcomputers prone stantly spark during motor operation. Lamp know when it's set. to electrical -noise problems than large main- dimmers with silicon -controlled rectifiers 12/24 -Hour Selection - You get conventional 12 -hour time frame computers, let us explore various or 24 -hour military time at the touch of buttons. Switch back the (SCRs) or triacs generate a small amount of and forth as often as you choose. Or, leave it on 12- or 24 -hour sources of noise and their effect on personal - noise on every alternation of the ac line time for as long as you want. A must for pilots. military person- computer operation and nel or anyone who needs the option of 12 or 24 hour time. suggest some meth- because of the rapid turn -on characteristics Powerful Solar Recharger - Fully recharges itself even in ods of reducing or eliminating the problem. of these semiconductors. artificial light. Power that's guaranteed for three full years with lite expectancy of many more. No more troublesome battery One might reasonably ask how power -line charges! Power-Line Noise. Of all environmental noise can get into a computer's logic circuitry Full 12 -Hour Chronograph - With 1/10 second precision, noise sources, -line noise is add time and lap time. Add time lets you time everything from a power perhaps if its very -narrow pulse widths cannot pass telephone call to a trip ... up to 12 full hours. Lap time lets you the best understood and most easily sup- through the power transformer and rectifier time each component within an event. Ideal for production man- pressed. High -frequency spikes and agers, coaches, sports fans, anyone with a critical time depen- "hash" diodes to actually change the dc supply volt- dent activity. generated by motors, switches, lamp dim- ages (large power -supply filter capacitors Continuously Shows: mers, and lightning are the most troublesome prevent this). It is capacitively coupled from SuRMoR Tuts WroTRnFR,Stl Hours, Minutes and Seconds types of power -fine noise. Measured at a wall the power supply's primary wiring directly into j Day of Flag Week outlet, noise I I I- -I Í AM/PM Notation in 12 -Hour this can be several hundreds or the regulated dc output wiring and then into ( Mode I I I _ even thousands of volts in amplitude. Fortu- the logic. In some computers with the primary nately for computer power supplies, however, wiring routed close to the logic circuitry, noise Quartz Accuracy- to a 5 seconds a month. the noise pulses are only a few microseconds bypasses the power supply altogether and

SUMMON in duration, so energy content is actually couples directly into the logic. It is not difficult Month, Day and Date-at TorsWruTRufRiSAT the push of a button. quite low. to visualize how even a fraction of a picofarad l l' I l l Nearby lightning strikes, of course, would of coupling capacitance can transfer =1 I I more generate spikes of the highest amplitude, but than 1 volt Shown: September 18 Tuesday (the typical noise -immunity specifi- strikes a mile or more away can also cause cation for most TTL and MOS logic) of the COMPARE THINNESS! trouble. This noise appears on an oscillo- original 1000-volt spike into the logic circuitry Thinnest Solar Alarm Chronograph available at this low price. scope as a rapid-fire series of narrow 'high - and possibly cause an error. (Note: most Seiko $250 10.5 mm voltage spikes. It can enter the power system computers are sensitive to noise only during Citizen $255 11.0 mm either from a direct strike on power -distribu- part of their bus and memory cycles; hence, it Texas Instruments $125 12.0 mm tion equipment or by induction. Since power is possible for the computer to ignore the Thin Solar $44.88 9.5 mm lines may be strung overhead for long dis- majority of noise spikes.) tances, they efficiently pick up electrostatic Preventing power -line noise from entering a Handsome Styling-Crafted, quality stainless steel back and bracelet. Optional goldtone model now available with 3 micron and electromagnetic fields radiated by light- computer is relatively easy-simply use a quality gold plating at $49.88. ning strikes and conduct the resulting spikes noise filter between the ac outlet and comput- 15 -Day No -Risk Trial -T it for 15 days, it you're not com- into the pletely satisfied with its quality and features, return it to us for a computer owner's home. er's line cord. Filters are most effective if prompt refund of your purchase price. In addition, there's a full Probably the power -line noise with the next located inside the computer's cabinet, right at One -Year Manufacturer's Warranty against defective parts and workmanship. highest amplitude is created by switching off the point where the power cord enters. Even if Easy To Order. Just call our toll free number below, or fill in the an inductive appliance, allowing energy installed at the plug end of the computer's line convenient order form. Order yours today! stored in the magnetic field of an inductive cord, however, they can be very helpful in GIEDJA f1ARKETfG, NC. device to suddenly release as the field col- excluding power -line noise. 10155-9 Plano Road, Dallas. TX 75238 lapses. For a few dozen microseconds, a very While filters are available from a number of O Yes! Please send me Thin Solar 12/24 -Hour high voltage is built up and may arc across sources, you might want to make your own Quartz Alarm Chronograph(s). with 15 -Day No -Risk Return the a - A Privilege, at 544.88 each, plus $2.50 postage and handling. open switch contacts, feeding high filter circuit. good power -line filter consists Texas residents add 5% sales tax. voltage pulse with a fast rise time into the basically of two L -section low-pass r -f filters Silvertone O Goldtane $49.88 power line. Ac induction motors and trans- (to provide both common- and transverse - Name formers-even those in fluorescent lamp fix- mode noise rejection), with inductors de- Address tures-are the most highly inductive. Large signed to handle several amperes of contin- City motors, such as those used in refrigerators uous current. Metal -oxide varistors (MOVs) State Zip and air an are included from Check or money order enclosed conditioners, create electrical to prevent possible damage For even faster service, charge to: noise even when they switch on because an direct local lightning strikes but do not other- O Master Charge/Visa Expires internal starting winding switches off when wise contribute to filtering out noise. (MOVs Account # they reach operating speed. Industrial plants act like high -power zener diodes, shorting out Signature with hundreds of very large motors and trans- electrical spikes that exceed about 300 volts ORDER TOLL FREE 1-800-527-7066 formers constantly switching on and off pre- in amplitude.) In Texas Call 1-214-349-3120 sent particularly hostile electrical environ- A property grounded three -wire ac outlet ©MMI - 1980 PE -5 ments for computers. and computer line cord are required for any

CIRCLE NO. 41 ON FREE INFORMATION CARD POPULAR ELECTRONICS

AmericanRadioHistory.Com C \C ,¢ \\¢ Ce Sk to le JC` i ,`r\`il hrJ ¢ F\ et` k .Q ¢<.Q `.Q t` \C c\Q k \ tís C e c` v s co Q e0 C, C ° c0 Q -o co and ELF II by run Netronics Write -the noise filter to function properly. With non - programs grounded outlets, filtering efficiency will be I very first night -even if you've very low and current leakage through the filter's capacitors could create a mild shock never used a computer before! hazard. You're up and running with video graphics for just $99.95 - Ac -line filters cannot cope with problems then use low cost add-ons to create your own personal system caused by low -frequency power surges and that rivals home computers sold for 5 -times ELF It's low price! Featuring M_.l' prerecorded tape cassettes. are "+«..,,,, dips. Unlike noise spikes, surges and dips R1802 ELF II Gives You The Power To Make Things Happen! long enough in duration for them to affect the COSMAC CPU --tit- Expanded. ELF II can give you more power to make things happen in the real that computer's dc voltages. The only defense Own a powerful home computer system, starting for just $99.95-a price world than heavily advertised home computers that sell for a lot more molten. gets You up and running the very first night...with your own TV for a video Thanks to an ongoing committment to develop the RCA 1802 for home computer is a wide line- against this type of noise display. 699.95 ELF II includes RCA 1802 8 -bit microprocessor addressable to 6111 use, the ELF II products -being introduced by Netronics-keep you right on the voltage range computer power supply or an bytes with DMA. interrupt, 18 registers, ALU, 256 byte RAM, lull hex keyboard, outer fringe of today's small computer technology. It's a perfect computer for expensive external ac voltage regulator. two digit hex output display, stable crystal clock for liming purposes, RCA 1861 engim'erigg, business, industrial, scientific and personal applications. video IC to display your programs on any video monitor or TV screen and 5alot Plug in the GIANT BOARD to record and play back programs, edit and plug-in expansion bus bens connectors) to expand Elf II into a giant! debug programs, communicate with remote devices and make things happen in Electrostatic Discharge. As you know, a ELF II Explodes Into A Giant! the outside world. Add Kluge Iprototypingl Board and you can use ELF 11 to tremendous static -electricity charge can be Master ELF It's $99.95 capabilities, then expand with GIANT BOARD ... solve special problems such as operating a complex alarm system or controlling KLUGE BOARD...1k RAM BOARDS...TINY BASIC...ASCII KEYBOARD... a priming press. Add ek RAM Boards to write longer programs, store more built up on your body simply by walking LIGHT PEN...EIF.BUG MONITOR...COLOR GRAPHICS & MUSIC SYSTEM... information and solve more sophisticated problems. across a carpeted or plastic -tiled floor- TEXT EDITOR...ASSEMBLER... DISASSEMBLER.-.VIDEO DISPLAY BOARD ELF al addons already include the ELF II Light Pen and the amazing ELFBUG Monitor -two extremely recent breakthroughs that have not yet been duplicated expecially in very -low -humidity environments. ... and another great reason for getting your ELF now - by any other manufacturer. When you reach for any metal, even without The ELF BUG Monitor lets you debug programs with lightening speed because coming into physical contact, the charge BREAKTHROUGH! the key to debugging is to know what's inside the registers of the microproces- And, ELF instead through your into what you release of sor. with the -BUG Monitor, of single stepping almost instantly dissipates Netronics proudly announced the programs, you can now display the entire contents of the registers on your TV touch. If what you touch is the cabinet of your the first 1802 FULL BASIC, written by L. screen. You find out immediately what's going on and can make any necessary computer, the rapid discharge can cause a Sandlin, with a hardware floating point RPN changes. The incredible ELF A light Pen lets you write or draw anything want on a running program to crash and, at its worst, math package (requires 8k RAM plus ASCII and you video display boards), $79.95 plus $2 p&h. Also TV seeen with just a wave of the "magic wand." Netronics has also Introduced even damage components in your computer. the ELF 11 Color Graphics Ye Music System -more breakthroughs that ELF 11 available for RCA VIP and other 1802 systems Static discharges make a tremendous owner were the first to enjoy! Board includes area for a ROM version. ELF II Tiny BASIC of noise. Charges of amount electromagnetic Ultimately, ELF A understands only machine language-the fundamental coding 5000 to 10,000 volts are not unusual and, Master This Computer In A Flash! required by all computers. But, to simplify your relationship with ELF II, we've introduced ELF i1 BASIC makes with ELF 11 a when discharged through a typical body Regardless of how minimal your computer backgenund is now, you can learn an Tiny that communicating breeze. impedance of 100 ohms, can flow at peak to program an ELF II in almost no time at all. Our Shorn Course On Micropro. censor b Computer Programming -written in noetedmical language -guides you Now Available! Text Editor, Assembler, currents of 50 to 100 amperes. Coupled with through each or the RCA COSMAC I802's capabilities, so you'll understand Disassembler And A New Video Display Board! typical rise times of 10 nanoseconds, this everything ELF II can do...and how to get ELF Il to do its Don't worry it you've The Text Editor gives you word processing ability and Ike ability to edit a programs text while it is your monitor. creates incredible noise amplitudes. been stumped by computer books before. The Short Course represents major or displayed on video Lines and charac- advance in literary clarity in the computer field, You don't have to be a computer ters may he quickly inserted. deleted ar changed. Add a printer and ELF II can To guard against electrostatic -discharge engineer in order to understand it. Keyed to ELF II, it's loaded with "hands on" type letters for you -error free -plus print names and addresses from your noise problems, a computer system must be illustrations. When you're finished with the Short Course, neither ELF II nor the mailing listl RCA will hold mysteries for you. ELF 11's Assembler translates assembly language programs into hesidecimal designed from the ground up to be resistant. 1802 any In fact, not only will you now be able to use a personal computer creatively. machine code for ELF II use. The Assembler features mnemonic abbreviations

The best defense is to make all exterior you'll also be ab'e to read magazines such as BYTE. . INTERFACE AGE... POPU- rathe- than numerics so that the instructions on your programs are easier to packaging from insulating material, such as LAR ELECTRONICS and PERSONAL COMPUTING and fully understand the read -this is a big help in catching errors. articles. And, you'll understand how to expand ELF A to give you the exact ELF ll's Disassembler takes machine code programs and produces assembly in is plastic. Then nothing the system capabilities you need! language source listings. This helps you understand the programs you are exposed for you to discharge to and static - 11 you work with large computers, ELF II and the Short Course will help you working with... and improve them when required. discharge problems are avoided. Fortunate- understand what they're doing. The new ELF II Video Display Board lets you generate a sharp, professional Get For Just 31 or 6/ character by 16 line upper and lower case display on your TV screen or realize this Started $99.95, Complete! ly, most manufacturers problem $99.95 ELF A includes all the hardware and software you need to start writing video monitor -dramatically improving Your unexpended 199.95 ELF II. When you and house their computers in plastic cabi- and running programs at home, displaying ,ideo graphics on your TV screen and get into longer programs, the Video Display Board is a real blessing! nets. But peripherals, such as disk drives and designing circuits using a microprocessor -the very first night -even if you've Now Available! never used a computer before. A-D/D-A Board Kit includes I channel (expandable to particularly printers almost always have ELF A connects directly to the video input of you TV set. without any addi. 43 D -A, A -D converters, $39.95 plus 52 postage & hand- exposed metal parts. throat hardwire. Or, with an 58.95 RF modulator (see coupon beiowl. you can ling.. While plastic cabinets bestow immunity connect ELF II to your TV's antenna terminals instead. o PILOT Language-A new text -oriented language that ELF II has been designed to play all the video games you want, including a allows you to write educational programs on ELF II with against direct static discharges, they provide fascinating new largellmissile gun game that was developed specifically for ELF speed and ease! Write programs for games...unscram- no shielding for the powerful electromagnetic II. But games are only the icing on the cake. The real value of ELF II is that it bling sentences.. spelling drills ..."fill in the missing gives a chance to write machine language programs -and machine language word" tests, etc.! PILOT is a must for any ELF II owner fields created by discharges to other metal in you is the fundamental language of all computers. Of course. machine language is with children. PILOT Language on cassette tape, only

the vicinity of the computer. Hence, in prac- only a starting point. You can also program ELF II with assembly language and 8/9.95 postpaid! Game Package on cassette tape (requires 4k RAM), tice, system crashes may be just as common tiny BASIC. But ELF Il's machine language capability gives you a chance lo $9.95 plus 52 postage & handling. develop a working knowledge of computers that you can't get from running only as with metal -cased computers. The ideal Clip Here and Attach to Your Order Below! cabinet would be metal encased in plastic. Netronics R&D Ltd., Dept PE -5 ORDERS ACCEPTED!( Road, New Milford, CT 067761PHONE This would not only just about eliminate the 333 Litchfield Call (203) 354-9375 Yes! I want my own Please rush me- static problem, but it would also prevent noise computer! RCA COSMAC ELF II language it s a earning breakthrough or engineers and laymen generated by the logic inside the computer 95 S postage alike S5 postpaid Total Enclosed 5 9 Ik1,r al 6 3 piuss geoan peruse Metal Cabinet with plexiglas dust cover for ELF II. (Conn res add tax) from escaping and interfering with nearby supply) $29 95 Pius 51 50 o&h IT! Exp. Date Power Surely Ireguiredl $4 95 pOSlpdrd for CHARGE --- Q I am also enclosing ppnent (including postage & handling) radio and TV reception. Q visa O Master Charge O RCA 1802 laser s Manual 55 Postpaid the items checked Demo.' If a (Bank/ ----1 you buy static -sensitive computer, (n tom Pitmans Short Course On Microprocessor b Computer I want my ELF II ward and tested with power supply. RCA there are several steps you can take to Programming teaches you lust about everything there is to know 1802 User's Manual anil Short Course-all for lust S149.95 plus about ELF it or any RCA 1802 computer Written in nomleche,cal $3 gbh. Account a reduce the incidence of crashes. The easiest ALSO AVAILABLE FOR ELF A 26 variables A.2. LET IF/THEN. INPUT, PRINT. GO T0. Programs and produces assembly language source list- O GIANT BOAROTM kit with cassette I/O RS 232. is to keep the computer in an environment SUB. RETURN END REM CLEAR UST. RUN, ings to help you understand and 'mprove your programs Cr Icy 110 8'nii P U0 decoders tnr is separate WO GO PtA1 PEEK. POKE Comes lully documented and in. $19.95 on cassette tape and to wear leather - instructions and a system monitor/editor $39.95 plus with concrete floors chines alpnanumenc generator 'equ,red to display SAVE 59.90-Teal Editor. Assembler & Disassembler 52 p&h your tv with. alpnanumenc characters directly on screen purchased together. only $49.95! (Require video pin- soled shoes. You can also obtain an antistat- Kluge 'Prototype) Board accepts up to 36 IC s On additional hardware Also plays lickackIoe plus a day Board plus ak memory I $17.00 Pius 5' pbh game 1! s Mre as a toy - ic floor with metal droning Mal uses ELF keyboard O ELF II Light Pen, assembled & tested. 37.91 plus S1 mat or carpeting threads Addressable to 1k page to O ak Stale RAM kit. any Slick ak memory required 614.9S postpaid p&n if 6ak 589 95 pus 53 p&h for II woven throughout you cannot move your Q Tom Raman s Short Course on Tiny Basic ELF Q ELF II Cdor Graphics & Music System Board kit Gold dialed 86 -pin connectors tone required for earn S5 postpaid se9.95 plus $2 p&h out of a carpeted area. Too, use of plug.m board) S5.70 ea postpaid computer O ELF-BUGTM Oeluse System Monitor on cassette video input ak O ELF II connects directly to the of nut tv o Expansion Power Supply Ireduired wnen adding ape Allows an registers a humidifier in room in which your comput- displaying the contents of on set without additional hardware To connect ELF II to the RAM( $34.95 Pius S208n Also 24 your Iv at any pant in your program displays your antenna terminals instead. order RF Modulator. with ASCII er is located will reduce the intensity of static PrAiessional ASCII Keyboard kit 528 bytes 01 memory with tall addremes, bunking cursor 58.95 postpaid upoertiower Case set 96 printable characters. onnoad and auto scrolling A must for the serious programmer' Coming Soon: A.D. 0-0 Converter, Controuer Board regulator pa, ty logic selection and choice or a hand. snags postpaid discharges. and more' snaking signals to «laic wim almost any compute Q In a 2 of teat Editor on cassette tace gives you inn ability to really tough cases, -watt resistor S6a.95 plus 52 OA insert. delete or edit lines and words prom your programs O Deluxe moat cabinet for ASCII Keyboard. 519.95 while they are displayed on your video monitor, (Add Print 1 megohm or more can be attached at one Otis S2 50 ben peinle, and you can use ELF. 11 to type erroriree letters Name end to your computer's, disk drive and printer Q video Display Board kit lets you generate a sharp. plus insert names and addresses horn your mailing list ) prolessionai 32 or 6a character by 16 line upper aun $19.95 postpaid Address cases. Then, when you approach your equip- Icever case display on your Iv screen or video monitor- O Assembler on cassette tape translates assembly dramaticalry improving your unexpanded 599 95 ELF tl language programs into hendecirrai machine code lo, ment, merely touch the free lead of the resis- (Fits side ASCil Keyboard cabinet 1 S89í5 ELF 11 use Mnemonic abbreviations for instructions City tor first to safely bleed off any accumulated Pros $2 p&n patner than numerics) make programs easier read O ELF II Tiny BASIC on cassette tape Coe, and help prevent errors 519.95 postpaid or Stale zip nnas'nciudea SAVE. l0Á0. . x. D. on cassette lace lakes machine cope static charge. -. O D,sassemsler DEALER INQUIRIES INVITED MAY 1980 95

AmericanRadioHistory.Com DISCOUNT PRICES Top Quality Money -Back Guarantee: All Factory Prime Computer Club MICROPROCESSOR IC'S Z-80 .. 8.95 6800 ...... 6.75 Z -80A 10.95 6802 11.50 80809 550 6502 ..9 50

. . 8085A . . 11 95 6504 ...... 9.50 28001 .. 189.00 6505 9 50 Directory Z8002 .. .. 139.00 2901 8 95 MICROPROCESSOR SUPPORT IC'S (Continued from April 1980 issue)

...... 8212 . . 2 49 280-P10 6.95 8214 .. 3.90 Z80A-P10 825 8216 .2.49 280-CTC ..6.95

8224...... 295 Z80A-CTC 8.25 8226 ...... 2.25 Z80 -DMA . 24.95 Pennsylvania 2377 Dalworth, No. 157 8228 ...... 4.75 Z80A-DMA 32.95 The Central Pennsylvania Computer Club Grand Prairie, TX 75050 8238 ...... 4.90 280-51 0/0 ...... 33.95 1979 Crooked Oak Drive Att: Bill Fuller 3251 ...... 595 180A -S10/0...... 37 95 Lancaster, PA 17601 8253... 1950 Z80-SIO/1 . . . 33 95 El Paso Group . Computer 8255 . . 5 70 Z80Z-$1O/1 . 37 95 Valley 8257 .. .. . 19.50 080-S1012 .. . 3395 Delaware Chapter, SCCS 213 Argonaut, #27

8259 . . . 1950 Z80A-510/2. . . . 37 95 1228 Barrowdale El Paso, TX 79912 6810. .. 4.75 6860 ...... 8.95 Rydal, PA 19046 6820...... 390 6520 . ... 675 Att: Martin Dimmerman Houston Amateur Microcomputer Club 6821 3 90 6522 9 75 (HAMCC) 6850 .. .. 4.10 6532...... 19.95 Kim -1/6502 User Group 4223 S. W. Fwy., #203 6852...... 3.90 6551 .. . 1375 109 Centre Ave. Houston, TX 77707 MEMORY RAMS PROMS EPROMS Morristown, PA 19401 Att: David M. Fogg

21141-450 ns 4 50 2101-450 ns 1 95 Att: Eric C. Rehnke 2114L-200 ns. 595 21L02-250 ns. . 1 10 Houston Amateur Microcomputer Club 4044-450 ns. . .425 21L02-450 ns...... 99 Northeast Computer Assoc. POB 37102

ns . . 4116-200 795 2111-450 ns . 295 834 Fowler Street Houston, TX 77036, 4116-15090...... 1295 2112-450 .... , , ... 1.9595 Philadelphia, PA 4096-5 . .. . 350 2147-85 ns 19.95

. . ns 8 95 MCM 6604 AC . . 350 2708-450 JSC Computer Hobbyist Club

AM 9060 CDC . .. 2.95 2716-450 ns ... . 2595 PET User Group NASA LBJ Space Center 5101-3. .. .. 4.95 2732-450 ns . 79.95 POB 371 Houston, TX 77058 Montgomeryville, PA 18936 Att: W. Jenkins SOUND GENERATORS Att: Gene Beals SN76477 Complex Sound . . .249 Generator MITIBUBUS AY -3-8910 GI Sound Gen (Add 53.001a manual) 64 Pgs . 1195 Philadelphia Area Computer Society 3845 LeBleu Street UARTS La Salle College Beaumont, TX 77707

AY -5-1013A . , 395 AY -3-1015A . 5 10 Science Bldg. AY -3-1014A . .. 650 1016028 3.50 20th & Olney Ave. NASA-JSC Computer Hobbyist Club Philadelphia, PA 19141 1011 LI N EAR LM 340T Series . 1.15 Davenport Att: Dick Moberg or Jon Bondy LM 301N-8 .32 LM 3875-8 . . 99 Seabrook, TX 77586

LM 30168 . ...32 LM 393N-8 . . .99 Att: Marlowe Cassetti

. . LM 3075-8... . 25 LM 39006-14 .. .58 Philadelphia Area Club LM 307H .. . 25 LM 39098-8.. . .99 404 Quince Street Northside Computer Group LM 308H . .75 LM 739DC-14 ...99 Philadelphia, PA 19147 5819 Brenda LM 3116-8 ...59 19 74101-14 19 San Antonio, TX 78240 LM 319H .. .. 90 LM 74768-14 . . .. 59 Pittsburg Area Club 1 Computer LM 320K Series .. 135 RC 1556NB-8.. . . 25 400 Panhandle Computer LM 3201 Series . .. 1.15 LM 4250CH.. .95 Smithfield Street Society IM 323K .. 4.95 CA 31301 225 Pittsburg, PA 15222 2923 S. Spring LM 3396-14 .98 LM 4136N-14 . .95 Att: Fred Kitman Amarillo, TX 79103 LM 340K Series 1 35 LM 3831 1 25 Att: Tex Everett St. Thomas District SOCKETS HS Club Permian Basin Computer Group Wire Wrap #3 Low Wire Wrap #3 Computer Low Ector County School Profile Gold Tin Profile Gold Tin 1025 Braddock Ave. PA POB 3912 8 Pin 14 49 29 22 Pin 28 .99 .69 Braddock, 15104 14 Pin 16 57 .37 22 Pin .16 .99 70 Odessa, TX 79760 16 Pin 20 .61 .41 24 Pm 36 110 85 Wilkes College Att: John Robenaldt 18 Pin .10 89 59 28 Pin 39 139 1.10 Computer Club 20 Pin 28 99 69 40 Pin .55 175 1.40 Math Dept. Texas A&M University Microcomputer Club Wilkes-Barre, PA 18703 POB M-9 SPECIALS OF THE MONTH Att: Eric Jansen Aggieland Station, TX 77844 While Supply Lasts Texas Computer Club ECL 101461 RAM 1 024 01-29 ns .. . 6 95 Puerto Rico Rt. 1 Box 272 AM 3705 PMOS 8 -Ch Multiplexer . 8.95 Caribbean Computer Club Alado, TX 76008 MM 500H Dual 25-90 Stall Register . 49 52 Kings Court, 4A TR1671 Asyn./Sync. Receiver - Transmitter 1695 Santurce, Puerto Rico 00911 Att: L.G. Walker 95890 Hi -Speed Div. 10111 Prescaler . 10 95 MCT6 Dual Optu Isolator 1500V . . 99 Rhode Island Theater Computer Users Group ICI 7107 CPL 316-0190 N0 Cono LED . .1150 Theater Sources, Inc. AY -5-2376 Keyboard Encolder 88 Keys 1050 Rhode Island Computer Hobbyists (RICH) POB 599 4712 Northway Drive AY -5-3600 Keyboard Encoder. 90 Keys 9.95 Dallas, TX 75206 1488 or 1489 liner Dnver/Receiver ... . 99 Bristol, RI 02809 18-Pin Low Profile Sockets End Stackable.. 10 Att: E.D. lannuccillo Utah Salt Lake City Computer Club HOW TO ORDER -Pay by chink. nedwrd, COD EoeeliotaymuS South Dakota Fulls Outer 6 , mkt or mad Frees vabu It. Isor day el Love one 2925 Valley View Ave $1000 mmvvan RCA 301 Users Group Sdnxurq - s< tot tree lnsi 2 tos For surface add 35c to ea add I nl Fa air add 70C Holladay, UT 84117 la excn adai to Wrerye- Cora l0'.. is sn,Roir4 and tomcat% COO s add51 85 Guar RR2, POB 585 anleed salistao00n a your money Lack We reserve the nllhi 10 Aral awrtellü sate Rapid City, SD 57701 items to pot sale We are not re50uaaao la tyro Virginia va,ecr Att: Jay Roman SEND FOR OUR FREE FLYER. Cantata cmgkae not 01 741.500 ICs Amateur Radio Research & Development Corp. (AMRAD) Texas 1524 Springvale Ave. Components Alamo Computer Enthusiasts McLean, VA 22101 7517 Jonquil Att: Paul L. Rinaldo Express, Inc. San Antonio, TX 78233 411 Att: John Stanton Charlottesville Computer Hobbyist Club 1928 Arlington Blvd #209 . PE 1380 E. Edinger, Unit Central Texas Computer Association Charlottesville, VA 22903 . Santa Ana, CA 92705 508 Blueberry Hill (714) 558-3972 Austin, TX 78745 Crystal City Computer Club "Have you kissed your computer lately?" 3008 Mosby Street Computer Hobbyist Group of North Texas Alexandria, VA 22305 PCB 1344 Att: Russell E. Adams CIRCLE NO. 11 ON FREE INFORMATION CARD POPULAR ELECTRONICS

AmericanRadioHistory.Com CQrandfatker''s ClocltjWas Never `Like Thi8 ! A Word About Creative Computing Dyna-Micro Users Club POB 1053 Lexington, VA 24450 You might think the term "creative Att: Dr. Frank A. Settle, Jr. computing" is a contradiction. How can something as precise and logical as IBM 5110/5100 Users Group 5541 Parliament Dr., Suite 104 electronic computing possibly be crea- Virginia Beach, VA 23462 tive? We think it can be. Consider the Att: Richard E. Easton way computers are being used to create in Microcomputer Investors Association special effects movies - - image 2415 Ansdel Ct generation, coloring, and computer Reston, VA 22091 driven cameras and props. Or an Att: Jack Williams electronic "sketchpad" for your home Peninsula Computer Hobbyist Club computer that adds animation, coloring 2 Weber Lane and shading at your direction. How .0I / Hampton, VA 23663 about a computer simulation of an Att: Larry Polls invasion of killer bees with you trying to Roanoke Valley Computer Club find a way of keeping them under 2026 Wynmere St. S.W. control? Roanoke, VA Att: Lee Yosafat Creative Computing is the number 1 magazine of applications and software. Tidewater Competer Club By "application" we mean whatever can 677 Lord Dunmore Dr. Virginia Beach, VA 23462 be done with computers, ought to be Att: Dawson Yeomans done with computers, or might be done with computers. Washington -Baltimore Computer Hobbyist Club 7711 Elba Rd. No magazine carries more on per- Alexandria, VA 22306 sonal computing applications than Att: Richard Rubinstein Creative Computing. Recent issues West Virginia have carried: West Virginia Computer Society 6 articles on investment analysis 167 Iroquois Trail 11 on word processing One, W. VA 25545 Att: Bill English The complete listing of Adventure 7 articles on artificial intelligence Washington 4 on controlling household devices Apple Core Computer Club 220 N. 2nd St. 1717 Comparison of 26 single board Yakima, WA 98901 computers If you love contemporary design but want Att: Jerry Stazinski or Russell Miller Comparison of 6 personal the more traditional, here is the clock for you. computers In creating our own version of the ever popular Hex's Users Group Rd. S 22 Educational applications Grandfather Clock, we use the electronic eye 36012 Military Auburn, WA 98002 18 Games and simulations to display each second, minute, and hour, and Att: Charles C. Worstill ti 9 Animation and graphics also the simulated pendulum motion. Northwest Computer Society techniques The diagonal model which has no simulated POB 4193 30 Evaluations and reviews of pendulum is available for wall mounting or with Seattle, WA 98104 systems and software packages base as a desk clock. Wisconsin 4 articles on communications Our synthesized sounds composed of tic toc, Durant Computer Club networks modified Westminster Chimes and Bongs are 901 S. 12th Street Plus regular columns on the TRS-80, available for any AMELECT clock. The chimes Watertown, WI 53094 Att: Bill Shier Apple, Pet, intelligent games, software, and bongs are composed of six frequencies, book reviews and new products. providing realistic bell sounds. They are totally Wisconsin Area Tribe of Computer Hobbyists within clock cabinet. (WATCH) Shouldn't you be subscribing to POB 159 Creative Computing? A one-year (12 The AMELECT clocks, cabinets may be Sheboygan Falls, WI 22306 your choice of Cherry, Mahogany, Maple, or Att: Don Stevens issues) subscription costs only $15 or Walnut hardwoods. protect yourself against inflation and FOREIGN COUNTRIES order 3 years for $40. Visa, MasterCard Assembled Kit Base and American Express are welcome.. Canada CL7401A Diagonal $75.00 $55.00 S8.00 Apple -Can Send order and payment to Creative CL7402 Grandpa S95.00 S71 .50 2180 Yonge St. Toronto, Ont., Canada Attn: Pamela, P.O.Box Chimes $45.00 S39.00 Computing, Att: Peter R. Zacharkiw 789-M, Morristown, NJ 07960 or call our and Handling, $4.00 Shipping Association of Computer Experimenters (ACE) toll -free hot line: To order write or call 220 Cherry Post Dr. Mississauga, Ontario Canada L5A 1H9 Allow 4 to 6 weeks for delivery Att: Ken Bevis !.w British Columbia Computer Society [800] 631-8112 203-1625 W. 13th Ave. (In NJ call 201-540-04451 Vancouver, British Columbia MELECT Canada V6J 2G9 Att: Karl Brackhaus

INCORPORATED Canadian Computer Club 203 7th East Postoffice Box 367 Saskatoon, Saskatchewan Canada S7H OW9 GOODLAND, INDIANA 47948 Att: Ian McLean computing Phone 219-297-3320 (Continued on page 98) 1creative=4,==4 CIRCLE NO.3 ON FREE INFORMATION CARD CIRCLE NO. 14 ON FREE INFORMATION CARD MAY 1980 97

AmericanRadioHistory.Com SEE YOUR'DEALER'TODAY PUT THE REAL DEMAND THE ORIGINAL® COMPUTER CLUBS LIFE ACTION OF Firestik' continued "THE FUEL -SEEKER" Canadian Computer Club OUR TOWN IN 861 11th St. DON'T TAKE NO FOR AN ANSWER!! Brandon, Manitoba THE #1 WIRE -WOUND AND MOST Canada R7A 4L1 YOUR SHIRT COPIED ANTENNA IN THE WORLD! Att: G. Pearson

Rugged, Shatterproof Fiberglass .. . Kitchener -Waterloo Microcomputer Club POCKET! Antennas and accessories for marine. RV. E2-3354 Electrical Engineering Dept. truck, auto. van and Stx channels of local as it hap- CB motorcycles, etc. University of Waterloo SIX COLORS: pens excitement packed inside Waterloo, Ontario "the smallest high-performance Clear. Spun -Gold. Canada N2L 3GL scanner package in the world" Silver -Gray. Black, Red and White. Att: Roger K. Sanderson Four bands of scanning action! 15 channels per second scanning! scanner Microcomputer Encounter Group Big features like built-in Watch for the New Film Scan Delay, Channel Lockouts 207-885 Old Esquimalt Rd. Manual SMOKEYand the BANDIT II and Channel selection. Victoria, BC Patented Track Tuning on UHF starring BURT REYNOLDS Canada V9A 4W9 bands. The Four -Six ThinScan- is and'Firestik' Antennas! Att: Varghese Cherian small enough to slip easily into a shirt pocket or purse. Now you Zd Montreal Area Computer Society can take all the excitement of police, fire and emergency A TOUCH OF CLASS! 4100 Kindersley Ave., 22 broad- Apt. casts anywhere you go. Outside Montreal, Quebec, Canada Measures 2.4 x 616 x 1:' Rubber ducky Vehicle antenna Included. Frequency range: Ottawa Computer Society 33.47, 152.164, 450-508 MHz. List price is Inside POB 5179.95. but from Communl- Vehicle 13218 cations Electronics' your cost is only firestilt' Kanta, Ontario 5119.00. These accessories are also 4NTENNAB Canada K2K 1X4 available for your Four -Six ThinScan- RIpeERUNNER Att: W. scanner, SP50 AC Adapter 512.00; sew WneR Mitchell SP51 Battery Charger S12.00: SP57 ypt1FNM xn RN. ea SCE VxM xn Carrying case with belt cup 515.00; 1.2 SEND FOR FREE CATALOG Societi d' Informatique Amateure du Quebec B-4 V. AAA NiCad'a (pack of 4)$15.00; A-135 cc Crys a certificate CP 9242 54,00 each. Add 95.00 per scanner for U.P.S. g ound shipping In the 'Firestik" Antenna Company continental U.S. or 99.00 for even faster U.P.S. a rshipping. Add $3.00 Sainte -Foy, PO for all accessories ordered at the same time. Order now by credit card. 2614 East Adams/Phoenix, AZ 85034 Canada G1V 4B1 Call our number below. Name Att: Gilles Paillard Street Toronto Amateur Computer Users Society FOUR-SIX THIN SCAN City (TACUS) 3 The Wynd State Zip Islington, Ontario, Canada Att: Kevin Crowston Serving the CB and COMMUNICATIONS Communications Market Since 1962. Toronto Region Association of Computer ELECTRONICS - .5 -YEAR REPLACEMENT WARRANTY Enthusiasts (TRACE) 854 Phoenix O Box 1002 O Ann Arbor, Michigan 48106 U.S.A. POB 545 Cell TOLL-FRE E (000)521 4414 or outside Ú.5.A.13131994.4444 CIRCLE NO. 54 ON FREE Streetsville, INFORMATION CARD Ontario CIRCLE NO. 1 ON FREE INFORMATION CARD Canada L5M 2C1 Att: Ross Cooling oFREE' Japan YOVRS Japan Microcomputer Club The world of GET Kikaishinko-Kaikan, JEIDA 5-5-8 Shiba-Koen, Minato-Ku Tokyo, Japan electronics Att: Kojiyada

Prof essor Haruhisa Ishida gee -wizardry University of Tokyo ;au 2-t 1-16 Yoyoi, Bunkyoko Equoirremi Beigiry rie ~sire OltbGeitahhrroiwBlcüvYp Tokyo, Japan Netherlands Hobby Computer Club . Delftsekada 12 ! e 2266 AJ Leidschendam .Or--- , , f '. Netherlands . W. Att: Dick Barnhoorn

New Zealand á elCO . , liatesae/ ,n4arlNerOMaitelCMAT. , -- t,1...';:-;1 1 and - Infofile rxu,...,ro.a rE.11..r POB 27-2068 t t Mount Roskill Auckland, New Zealand v

.,aw ye United Kingdom N -r v S 5_ Amateur Computer Club iy;a mew+seiersoamn<"nR' 7 Dordells .--=----. Basildon, Essex -- "' England Att: Mike Lord nagil British Amateur Electronics IN 11 Hazelbury Dr. MUSÓÑICS Warmly, North 'S Bristol v> NEW IDEAS EI.ECTR England r ----=----- 1 Att: J.G. Margetts PLEASE RUSH MY Computer Workshop -YOURS FREE. 174 (field Road 32 -pages of test instruments from the London SW 10 9AG, England - FREE 1980 CATALOG latest digital multimeters to the famous To have your club listed in an addendum EICO scopes. Security systems. Auto- name motive and to this Directory, send information to: hobbyist products. Kits and address assembled. EICO quality. EICO value. Computer Club Directory For FREE catalog, check reader service city state zip POPULAR ELECTRONICS card or send 50é for first class mail. One Park Ave. ~ELECTRONICS. Oept. 5-P 1020 W. Wilshire. Oklahoma City, OK 73116 New York, NY 10016 j 108 New South Road J / ' CIRCLE NO. 53 ON FREE INFORMATION CARD C/ /Cali/` Hicksville, N.Y. 11801

CIRCLE NO. 22 ON FREE INFORMATION CARD AmericanRadioHistory.Com "If you already own a Scientific Calculator, I'll show you how to become a Math Wizard in 10 days! Step up your job skills. Impress your colleagues. Get the answer FIRST in your next conference."

Quickly and easily you'll be doing real math: Algorithms/Functions Triangles/Trigonometry Differential Calculus Differential Equations Sequences/ Series Limits! Continuity Areas and Volumes 'Quick 'Guaranteed Integral Calculus Logarithms/Exponentials Curves/Polar Coordinates 'Easy 'And fun, too!

All this with the Scientific Calculator you now have! marginal costs, motion, cooling, probability, pressure MONEY -SAVING OFFER Now you can step up your math skills fast, even if - and plenty more. If you studied this method in a Seminar, you'd have to you think you've the you once forgotten math knew. Important numerical techniques? They're here, too pay around $500. Even a run-of-the-mill calculus text Send for my new, in prove i -effective method --rational and Padé approximation, bracketing, con- today costs about $20. But, for a limited time, you can guidebook form. It's entitled 'CALCULATOR tinued fractions, Euler's method, Heun's method, invest in 'CALCULATOR CALCULUS' for only CALCULUS' and comes with this firm money iteration - -back functions, Newton's method, predictor 514.95, shipping paid. I use the word "invest" because guarantee: If after 10 days you're not absolutely as- corrector, successive substitutions, Simpson's method ii will pay for itelf fast. (Tax deductible for profes- tounded at the problems you're solving on your Scien- and synthetic division. sionals.) tific Calculator, send the guidebook back for a full and NO RISK WHATEVER immediate refund of your money. No questions asked. LOOT( AT WHAT USERS SAY Order your copy today. Write the words But the point is -- you won't want to send it back. For Professor John A. Ball of Harvard 'CALCULATOR CALCULUS' on a slip of paper here is the easiest and fastest shortcut ever. College (author of and the book 'Algorithms for RPN Calculators') writes: "1 send it along with your check or money order. Be sure Let me introduce myself. My name is Dr. George wish I liad had as good a calculus course." to give me your complete mailing address. If you want McCarty. I teach math at the University of California, Professor H.I. Freedman the of to charg it to your Visa or MasterCharge Irvine. This new guidebook is the result of the of University Alber- account, in- ta, writing in Soc. Ind. Math. Review, clude your Card. No. and the recognized need to cut through the confusion. It does Appl. states: Expiration Date. "There can be no as to the California residents please add tax; just that through WORKED -OUT EXAMPLES, question usefulness of this 6% sales foreign add $2 Airpost. SIMPLE EXERCISES and PRACTICAL PROBLEMS. book...lots of exercises...very clearly written and makes for easy reading." Prompcshipment guaranteed. If 10 The very day you receive your copy in the mail, you'll after days you're C.B. of Santa Barbara, says: has not astounded at the problems you're send want to put it to work. It's that exciting and helpful. CA "Your hook solving, given me much instruction and pleasure. the book back for a and refund. Even people who have not tackled math problems in I do not full prompt hesitate to recommend it. Remember, you don't risk a years find it easy to follow. What's more, it's fun! 'CALCULATOR CAL- cent. CULUS' is a book that inspires the reader to under- Discovrr just what you can do with your Scientific HERE'S HOW YOU WILL BENEFIT stand everything down to the last detail. You seem to Calculator by sending for 'CALCULATOR Need to evaluate functions, find their zeros, differen- have put your heart into the teaching part of good CALCULUS' today! Thank you. tiate and integrate them, even solve differential equa- writing." tions? It's all here. No matter your work -- educator, practitioner, or ©1980 EduCALC Publications, Dept.E If you're in the biological, social or physical sciences, just someone who enjoys the Scientific Calculator and Box 974, Laguna Beach, California 92652 you'll be doing Bessel functions, carbon dating wants to do more with it -- you'll find Toll-free Credit Card orders 800-854-0561 Gompertz' growth curves, half-life, future value, 'CALCULATOR CALCULUS' a joy. (in Calif., 800-432-7257) - ext. 845 - Dept.E

Put Professional Knowledge and a NOW! For the first time ... a clear, concise, understandable book COLLEGE DEGREE on the Earth's most promising energy source. in your Electronics Career through HOME Solar Electricity $o°95d6p 140 EASY-TO -READ FACT educational. consumer. and military applica- FILLED PAGES tions. It also includes solar electric projects. com- STUDY ' e it (ti. Í Loaded with charts, graphs, pic- mercially available accessories the use of solar ili .. tures of actual solar installations.- cells as light sensors rather than as ®$SMn by World's Foremost Authority power sources, and much, much r 411111 - yti5 SOLAREX more. Most books and articles on Solar Don't take our word for it! Energy are either jam packed with Take your time. In fact-take two Earn mind -boggling technical jargon, or full weeks. Order the book. Read it. Your they're so basic you can't find what See if you don't completely agree DEGREE you really want to know. that this is the best Solar electric Here for the first time-is a definitive summary you've ever read. If not- No commuting to class. Study at your study of all the real (not blue sky) ap- simply return the book and we'll refund your money by return mail own pace, while continuing your present plications of solar, written by the world's leading experts . . but or credit your account. job. The Grantham home -study program written in everyday language so /Only Use handy coupon below or you can understand and put to phone 301-948-0202. leads first to the A.S.E.T. and then to the 5°^asE work the real. significant benefits ppd Dealers' inquiries invited. B.S.E.T. degree. Our free bulletin gives I of Solar electricity in scores of STOCK NO. 37005DE... $6.95 Ppd. -80. practical ways, both large and small. full details. Write for Bulletin ET COMPLETE AND ORDER TODAY Must reading for everyone from the ca- I CPD-Dept. 100 DE 1335 Piccard sual enthusiast nght to the Drive Grantham College of Engineering up trained SOLAREX CORP Rockville, MD 20850 solar professional. 2500 So. LaCienega Blvd. o Please send ow copies of "Guide to Solar Nine Clear, Concise Chapters Electricity" ra $6.95 each $ $1.00 Los Angeles, California 90034 Covers everything from a glossary of Shipping & Handling V/S4` solar electric terms. how to use cells and TOTAL practical 0 1 solar electric generators. to the 1 Md. resident please add 5%1 rapidly exploding variety of industrial. Enclosed is _check. M O in amount of $ GRANTIIAM'S FCC LICENSE STUDY GUIDE Charge to my' VISA MASTER CHARGE CPD-Dept. 100 DE -377 pages, 16 FCC -type practice tests, 1465 ques- ISOLAREX 1335 Piccard Drive, Account No tions with answers and discussions-covering third, Corporation (Interbank No.) IIIIIIIIIII Rockville. MD 20850 second, and first class radiotelephone license Signal u re' Visa/Master accepted exams. Preparation for each separate class of li- Charge credit cards Name 1'11 /w1 VNlr.l is cense is presented a separate section of the Address: book. $15.75 postpaid. Order from: 301-948-0202 Minimum Order $15 (Two or More Books) City State Zip GSE Publications eee,'M,n,mum Order st P. O. Box 35499. Los Angeles. Calif. 90035 CIRCLE NO. 71 ON FREE INFORMATION CARD

AmericanRadioHistory.Com TRS-80 CP/M. Working with CBASIC and all Catalogs of Interest. Software Dynamics, other CP/M programs, this TRS-80 Mod -II 2111 W. Crescent, Suite G, Anaheim, CA Software in CP/M requires no changes the operating 92801 (Tel: 714-635-4760) features SDOS, a codes. Source and object files will both work 6800 Operating System; EDIT, a general-pur- Sources on the system and programs from other CPI pose context editor; MAL, a 6800 Assembler; M code suppliers will be fully compatible. IDB a 6800 interpretive debugger; SD BASIC Leslie Solomon $249.95. MPU, P.O. Box 808, San Carlos, CA V1.3, a business BASIC; a chess program Technical Director 94070 (Tel: 800-824-7888). compiled by SD BASIC; an I/O package; and a relocating assembler. Future programs include a relocating debugger for 6800/6809 and a link editor for the 6800/6809. The Bottom Shelf, Inc., P.O. Box 49104-C, Atlanta, GA 30359 (Tel: 404-939-6031) features TRS-80 Level -II programs including: MICROCOMPUTING Checkbook II that has a five -column screen display with a field for alphanumeric codes. a Screen prints can be made to a line printer, or diskette ($18.50); Information System, a data MAKE YOUR MOVE OW base manager that allows up to 40 characters per category and 200 characters per page ($24.50); and Exerciser allows user to create physical fitness goals and analyzes progress toward the goal ($12.50). Other software available includes BASIC Toolkit, System Doctor and Terminal Control, Busi- ness Mail List, Data Base Manager, Check Register Accounting System and Analysis .. to receive' the magazine that gives you more Pad, and Library 100. articlet for your money than any other publication in Microware Systems Corp., P.O. Box 4865, Des Moines, IA, 50304 (Tel: 515-265-6121). the. field. Subscribe today. The 6800 software available includes A/ BASIC, a true 6800 BASIC compiler which is ROMable. The A/BASIC Interpreter is source - Enclosed is: $18 for 1 year $45 for 3 years Bill Me compatible, extremely fast and implemented Name as an incremental compiler. It may be used as Address a text editor for the A/BASIC Compiler. The City State Zip A/BASIC Source Generator is an optional enhancement for the A/BASIC Compiler (disk Canada - $18 In US funds tor one year; other foreign $26 one year In US funds. Please version only) to permit it to produce assembly allow weeks for 6.8 delivery. 705BP language listings and source programs. This Kilobaud Microcomputing / POB 997 NY 11737 /Farmingdale firm also has a LISP Interpreter and 6800 Chess. kilobaud T.M. Surveyor Package. For use with CP/M and BASIC, this program includes traverse (open MICROCQMPUTING or closed) with sideshots, stadia reduction, universal triangle solutions, volume by aver - THE ENCYCLOPEDIA OF MICROCOMPUTING (continued on page 102)

CIRCLE NO. 38 ON FREE INFORMATION CARD

For more "-!Level II. 16K information on RS -80* $669:° advertised Keypad not included. products, A trademark of Radio Shack and randy Corp. equipment tested, etc., Smart Terminal Package... circle Level II, 4K: CAT MODEM: RS -232C Port: appropriate Parallel) Printer Port: ST80 UC Term Software. number on s899;0____ postpaid 800258-1790 Free - 9 QUESTIONS: Information (603) 673-5144 Card. 6 South Street. Milford. NH 03055 CIRCLE NO.29 ON FREE INFORMATION CARD 100 POPULAR ELECTRONICS AmericanRadioHistory.Com THE, ma'.!WI PÚTERJMART

_ COMPUTER RETAIL-STORES

MICROCOMPUTER MART RATE: 1" x 1 Column (1-5/8") $125. 1-1/2" x 1 Column (1-5/8") $187.50. 2" x 1 Column (1-5/8") $250.00. For frequency rates, please inquire. GENERAL INFORMATION: Advertising copy must be typewritten or clearly printed. Payment must accompany copy except when ads are billed on credit cards-American Express, Diners Club, Master Charge, VISA (supply Expiration date)-or when ads are placed by accredited advertising agencies. Ads are not acknowledged. They will appear in the first issue to go to press after closing date. Closing date: 1st of the 2nd month preceding cover date (for example, April issue closes February 1st). Send order and remittance to MicroComputerMart, POPULAR ELECTRONICS, One Park Avenue, New York, NY 10016. For inquiries, contact (212) 725-3485.

ILLINOIS GEORGIA FRff'software catalog All your business & for Apple II J personal computer Radio lhaek R Q needs. SALES SERVICE LEASING COMPUTER CENTER Extensive Software & of Peripherals Stock. 11C130 UANAGEC1E1:1T APPLE ATARI DEC As a Radio S4TiacÍx l Authorized Sales Center owned Or operated Plus all PERIPHERALS & SUPPLIES r SYSTEUS 708 S. Main St. 1 by Pan American Electronics, Inc., Open Tuesday through Sunday we can sell them for less. No taxes (312) 495-9889 Lombard, IL 60148 VISA and MASTERCHARGE collected on out-of-state ship- ments. We pay shipping Or insurance. RAINBOW COMPUTING, INC. TOLL FREE 800/531-7466 , CALIFORNIA 9719 Reseda Blvd. Up lo 15% Discount Texas 13 Main No. 512/581-2765 Northridge, Ca 91324 on TRS-80's 1117 Conway 349.5560 (213) We have the highly reliable Mission, Texas 78572 I~11 Lobo Disk Drive in stock! OHIO Mini-Mail-Downtown Shopping Center Cairo. Georgia 3172a MICHIGAN OHIO SCIENTIFIC 01121 377.7120 G., The fetal, 6 Oar lo. P.ire+ Data Products Maintenance 128 N. Gorreld Ave.. 51/4" +8" Diskettes, $2.99 ea. (Boxe: of 10) Monterey Pork. CA 91754 BAND-ORCH, INC. 0.S.1. 11 -OEM 48K, AMCAP Software, 12131 573-5991 r (714)904-4180 TEXAS Reg $3,874 Now $2.995. Complete Ohio CROMEMCO SYS-3, 64K, Dual Sided 8" Scientific Line Reg. $6,990. Now $5.695. 337 East State Street Other Discounts as well. Shipping Extra. The Original LLOOK!! ' Rt. I, Box 193 Alliance, Ohio 44601 THE Ber,ien Springs TRS-80' Computer Owners (216) 821-2600 FIBACLIS Micligan 49103 MEGASAVINGS! ' VISA/Master Charge ByteShop® 16151429.3034 1415 W. El Camino Real Brand new Percom mini -disk Mountain View, CA 94040 systems: Single -Drive - $325: (415) 969-5464 NEW JERSEY Double -Drive - S650: Triple - NEW HAMPSHIRE Drive - $975. 16K -Byte Memory: 8 prime 4116 ICs $64.95 COMPUTER MART - s advertised in OHIO SCIENTIFIC ° Introductory paces good for a limned time 0 Microcomputing & MICRO -COMPUTERS OF HEW JERSEY only. Paces do not Include slopping, or ilobaud Microcomputing Magazines 501 Route 27 sales tax If applicable. A.A. Office Iselin, N.J. 08830 CALL Toll -free 1-800-527-4196 TRS-80 16K LEVEL II Equipment Company (201) 283.0600 15296 E. 14th St. The ACCESS UNLIMITED CE CpS AOG s7 3 0°° s frt. Microcomputer MAIL ORDER MICROS San Leandro, CA 94578 315 N. Shdah . Ste. 01 Gadand, TX 75042 (415) People 12141 494 0206 olvlof Eo]424]04 357-1737 tt I 11

am am me me am um um um us am ma um' 1 SUNDRIES AND NOTIONS FOR USERS OF I FLOPPY DISKS FROM THE SOFTWARE SUPERMARKET I .9/,, . 7/ás -f0,3> ;,/1~, z) ;

1 FLIPPY*******************1 DISK HEAD CLEANING FLOPPY SAVER Please send me the following: Protection for center KIT Template DISKETTE Cleans Item Price 1 and instructions the drive read/write holes of 51/4" floppy , to modify single head in 30 seconds. disks. Only 1 needed I side 51/4" disk- Diskette absorbs loose per diskette. Kit con- ettes for use of oxide particles, finger- tains centering post, I I second side in prints and other foreign pressure tool, tough :° Lifeboat Associates single sided particles that might 7-mil mylar reinforcing I I - drives. hinder the performance rings. Installation THE I $12.50 of the drive head. Lasts tools and rings for SOcFiTWARE I at least three months 25 diskettes. I with daily use. Specify $14.95 I ; C.O.D. I Credit Card SUPER- I Master Charge tel charge 5"or8" $7.95 (Re -orders of MARKET or Visa 8 I $20. each $55. for 3 rings only) I Sh ppinglhandling charges extra. I I Name Address ILifeboat Associates,TM N.Y NY 10024 State Zip 2248 Broadway, E City (212) 580-0082 Telex 220501 `tamet:aA--a--me im m---aaamafa-fafafafafaam all CIRCLE NO. 39 ON FREE INFORMATION CARD

AmericanRadioHistory.Com 44 \c a THE ONE -STOP N Q I a MUSIC SHOP -í \9$1.\ 0: .0 -rS .0 AT WHOLESALE PRICES BOOKS FOR THIS MONTH'S SOFTWARE SOURCES cont'd SUPER SPECIALS! age end area, circular curve solutions, hori- THE HOUR... CAR STEREO 511,: zontal curve layout, universal intersections, vertical curves and grades, volume of a bor- sa - (h CASSETTEE IN -DASH PIONEER' row pit, and coordinate transformation. Gra- WITH RADIO CASSETTE IN -DASH FT.ir 98 . 5259 90 ham -Dorian N. F1-2400 WITH RADIO Software Systems, Inc., 211 AP 3129 9 0 F1.4B9 139 90 103.3500 44 90 Broadway, Wichita, KS 67202. FT -646 151.90 KP.5005 14490 FT -I493.2 164 90 KP-0000 154 90 FT -1495 169 90 KP-8005 154 90 R.642 94 90 KP.8500 179 90 FT -644 .106 90 COP400 Assembler Editor. The ASMB- 65.2000 184 90 CASSETTE UNDERDASH KE-2002 _20990 10-1400 COP400 assembler/editor development sys- .S 95.90 KE3000 . 274 90 77.1405 .. 111.90 KE-5000 .. . 274 90 tem can be used with the North Star operating KP%.9000 ...... 184 90 JENSEN KPx-9500 .. 209 90 system. Programs developed on a Z80/8080 J11901(6.9 CASSETTE UNDERDASH

KP-272 .. . 90 Separates) 50*911. 594.50 .569 host must be off-loaded to the target proces- 21065 6,9Tna.- 5) .62 50 1(7.373 ... 84 90 sor. The complete instruction set fór the J1033 (649 Tux (1- KP-250 ...... 104 90 100 Walls) 78 50 KP.500 .129 90 National J1101 (4x10 Tria, AP-575 99 90 COP400 is. supported, as well as 45 Walls) 62 50 67.660 .. 89 90 pseudo . . . 41130(4.901rM, II. KP.770 114 90 -operations for conditional assembly, 50 Watts) 78.50 KP.88G 109 90

41174 (51. Tux- KPK.600 . 129 90 data and string definition, and multiple loca-

. 50 62.50 80.7075 16490 J1175Wans)nax'W1atts) 11 POWER AMPS/EOUALIZERS tion counter program development. On dis- 78 50 ÁD392912 Walls) 539 90 J1069 (60 Coa, - 4D-320120 Watts). 4790 kette with documentation is $75. Allen Ashley, 5 Watts) 39.50 AD360170 Watts 13990 21037(6e9 Coa. II - 60.30 (5 Band Ell.) .9490 395 Sierra Madre Villa, Pasadena, CA 91 107 o 90 Watts) 58 50 40.50 (5 Band E9 9 .159 90 41077155. Coa. - GM -12(12 Watts) 3190 (Tel: 45 213-793-5748). HOU: Watts) 39 50 04.50(20 Watts) . 52 90 21075 al. Coa. II 06.120 (120 Watts) . .. .129 90 It41 s) 46 50 00.717 Band 69) 12990 We carry the lull line of car CAR SPEAKERS 8080/8085 Books. The two -volume 8080/ TS -e2 Tweeter . 2B 91175 equipment by such names as . ' TS . IS -T3 NOW! Tweeter 39.90'79 8085 Software Design handbooks (Book 1 at Sanyo, Craig, Marantr, TS -168 Three Way .. ea 90'PR Pioneer, Jensen& Audiovox. 15-694 6,9 Coax . 59 901PR $9.50 and Book 2 at $9.95) published by New! BASIC COMPUTER PRO- 79-695 6x93 Way . 89 9%PR Write for tree catalog. TS -x62 Way Surface 6990175 Howard W. a GRAMS FOR THE HOME 1x.092 Way Syrlace 134 90'70 Sams form complete compila- (Stern- tion of programs and subroutines for the berg). Over 75 home application .,I3LANN'ÍAPES 8080/8085. Included in each program and programs. Each is documented with CASETTE TAPES Ampex Grand Master 11C-90 3 11 subroutine is an in-depth study of the goals a description of functions and oper- 2 79 REEL-TO-REEL TAPES 17"114'''''C'SPF 2.88 S00101 212 18 00 FT 4.35 that the software must accomplish, ation, a listing of the BASIC pro- BASF P101101(11 C-90 2.99 Scorn5001511207800 ET 5.19 the Fop 1Ior II C-OO 2.99 MK 1.1800 1800 FT 5.22 instructions used, and the strong and weak gram, a symbol table, sample data, 5colcn to Herea-%l306 4999 VIDEO TAPES Scolds Master 111C-90 329 BETA FORMAT points of the developed software. The TEA and one or more output samples. Sony C-90 1 64 TM( 1-500 Hour) Sony HFxc-90 235 (2 . .12 95 Sony 1-500 Hour) . ..12 Sony Fernehrome C.00 .3 25 (2 95 (Tychon's Editor Assembler) at $8.95 #5154-9, $8.95 Fop de- 70110C-60 119 1.500 (2 Hour) ..12.95 Scotch 1.500 Hour). TDK -90DC 1.68 (2 ..12 50 scribes this co -resident editor -assembler in- Sony 1.75013 Hdor) 17.50 TN DC -120 210 . New! HOME COMPUTERS CAN TDKDC-100 299 VHS FORMAT cluding source listing, while the DRUG 8080 TOK As C-60 t 68 Maxell 7.120)4 Hour) . 14.95 MAKE YOU RICH (Weisbecker). 10640C% 2.45 MK T.120 (4Haur) 1495 Interpretive Debugger at $4.95 illustrates a TOK AD C.120 348 JVC T-120(4 Hour) . . 1395 Introduces the home computer own- 14 101(5A C-60 2.15 lop 1-12014 How) . 95 MK program for entering, debugging and storing SA 0.90 3 16 Scotch 0K-25014 Hour) 4 95 er and nonowner to the microcom- MINIMUM ORDER 12 TAPES -100% GUARANTEED assembly language programs, complete with . Call or write for super low prices on Maxell tapes. puter industry and the people source code. All books are from the Blacks- involved in it. Discusses money- CARTRIDGES burg Group of Christopher Titus, Peter Rony, making opportunities in freelance audio-technica David Larsen and Jonathan Titus. writing, AT -20S5 .. 134.95 programming, consulting, 41.1555 89.95 AT VIS inventing, and much more. #5177-8, -145A . . 49.95 Typey 8990 II1 AT.12SA . 79.95 4M9155eTyy 6250 CP/M for the Altair. Implemented on the 07.10 12.95 . 3 0 $5.95. sY33NTpe M95E0 .. .29 90 Altair and MITS 3202 series of floppy disks, 09150 50 881S 79 95 .20 5B1EEE-5 044E the Altair New! DR. DOBB'S JOURNAL OF 59.95 070E4 CP/M allows access to all CP/M 681EEE 49 95 . 990 680EE 17 95 software. $145. Lifeboat Associates, 2248 COMPUTER CALISTHENICS & 500E 14 95 ©PICKERING 0SW5000 ...... 8990 Broadway, New York, NY 10024 (Tel: 212- ORTHODONTIA Vol. 1, 2 & 3 fJ1rrENPIFE x543000 4590 20002 54 50 0915/50 34 90 580-0082). (The People's Computer Company 20031 .29.50 0015625 . . 24 50 9915400 2000E/111 18.50 21 50 Series). Each volume includes al- 9 WA 114 50 P/AC . 9 90 OSI Sort. BPSort is a high-speed, machine - most everything from all issues of 1 ACCESSORIES ,w code sort/ merge utility for Ohio Scientific Dr. Dobb's Journal. Vol. 1 reflects DISCWASHER Complete System floppy and hard -disk systems. 20,000 bytes the changes that took place in per- 0,561 34 95 t1 n HEADPHONES sonal computing in 1976. Vol. 2 95 Koss Pro 4ÁA can be sorted in 10 seconds. Files can be as . . 39 90 11`á3164 5d151 10 95 Koss Pro 44ÁA 46 Zerostat s ane Gun 1495 50 (1977) looks at the of Koss HVVIC long as an entire hard or soft disk and five emergence SC -1 a 95 Koss HVVA Dlsdaol 15 95 31.50 small Sennnnse, 00414 42.50 keys handle ascending and/or descending the computer as a useful tool. Fue/buster It Radar Delectar 82 90 Sennnn5et 00424 64 50 Beam Box FM -8 Antenna 34 50 Sennnetset 00020 ... 4950 sequence. Sort parameters use a simple Vol. 3 (1978) chronicles the grow- Beam Boa FM.It Antenna 64 50 Sennnelser H0430 72 50 BASIC program. BPSort is OS -DMS compati- ing interest in programming lan- RECORDS ble and is supplied as part of the BPS Inter- guages, along with articles on active Data Management System. $124 from specialized applications and utilities. Pop. Rock. Jazz. R&B BPS, 322 W. 57 St., New York, NY 10019 Vol. 1, #5475-0; Vol. 2, #5484-X; All 7.98 List $4.99 (Tel: 212-765-0815). Vol. 3, #5490-4; each $18.95. All 8.98 List $5.49 o All 9.98 List $5.99 Available at your local 50. add,ttunal Ior cassette or 8-1,acw, please speedy: TRS-80 Statistics. The Advanced Statisti- Minimum order: 525.00 cal Analysis package may be used with Level computer store! WE STOCK THE COMPLETE SCHWANN CATALOG. II BASIC or Disk BASIC on a 16K TRS-80. HOW TO ORDER. For Immedlere shlpmenl, sand money order or Or Toll FREE, 24 certified check. Two reeks delay on personal checks. Please add Included in the system are 10 programs for Call hours a day, 03.50 p r order for shipping a handling ($6.58 for orders outside describing data sets and conducting statisti- (1-800-827-3777, ext. 302)' continental U.S.) M.Y.S. raldenla add tea. Payment must De In U.S. Wm Ny. No C.0.0: s. All merchandise 1001. guarsmeed, orsnd cal data analysis; two utility programs for pre- TO CHARGE YOUR ORDER TO new i factory fresh. paring, updating and listing data files stored Master Charge or BankAmericard! on tape or disk; and a program to aid in MUSICAI, selecting data samples. Programs include Minimum order is $10.00; tape data files, disk data files, random sam- customer pays postage and handling. WORLD ple, descriptive statistics, histogram, frequency distribution, analysis of T -test 'From Missouri, call 33 PARK ROW, DEPT. PE, NEW YORK, N.Y. 10038 variance, for TO ORDER: CALL MON-SAT 9AM-6PM EASTERN TIME matched pairs, correlation and linear regres- 1-800-892-7655, ext. 302 TOLL FREE (800) 221-8180 sion, multiple linear regression, time series ALL OTHER MATTERS: CALL 12121 732-8600 analysis, and chi square analysis. $39.95 at Hayden Book Company, Inc. 50 Essex Street, Rochelle NJ CALL OR WRITE FOR FREE 1íiÓ PAGE CATALOG. Radio Shack stores or computer centers. Park, 07662 . e CIRCLE NO. 30 ON FREE INFORMATION CARD 102 CIRCLE NO.37 ON FREE INFORMATION CARD POPULAR ELECTRONICS

AmericanRadioHistory.Com Light-Wave Voice Communicator

BY FORREST M. MIMS

THIS MONTH'S project is an amplitude - power amplifier. Potentiometer R2 is the through a single optical fiber. Of course, modulated light -wave voice communi- gain control. you'll need two complete transceivers to cator that you can assemble from inexpen- You can use various kinds of detectors fully use this operating mode. sive, readily available components. You as the front end of the receiver. Phototran- can use the communicator to send and sistors are very sensitive, but they do not Going Further. This transmitter and receive high -quality voice signals over dis- work well in the presence of too much receiver system will send voice across a tances of hundreds of feet through the ambient light. Note that a 100,000 -ohm room without the need for external optics. atmosphere or through an optical fiber series resistor is required if you use a pho- For ranges of hundreds of feet, you must "waveguide." totransistcr. Solar cells and photodiodes use a lens to collimate the light from the work well. So do LEDs of the same semi- LED. You must also use a lens to collect The Transmitter. The transmitter, which conductor as the transmitter. and focus light on the receiver's detector. is shown schematically in Fig. 1, employs a An interesting aspect of using LEDs as For more information on the use of lenses 741 op amp as a high -gain audio amplifier detectors is that, although they are not as and related subjects, see Light -Beam which is driven by a microphone. The out- sensitive as phototransistors, they are Communications (F. Mims, Howard W. put of the 741 is coupled to Q 1, which much less sensitive to the adverse swamp- Sams & Co., 1976). serves as the driver for a LED. Potentiom- ing effects of ambient light. Using a LED as It's difficult to align the invisible beam eter R1 is the amplifier's gain control. Min- a detector also means you can switch the from an infrared transmitter LED, but you iáture trimmer resistor R6 permits adjust- LED's anode between the input of the can eliminate this problem and communi- ment of the base bias of Q 1 for best trans- receiver and the output of the transmitter to cate around corners by using an optical mitter performance. form a light -wave voice transceiver capa- fiber. See this month's "Experimenter's Gain control RI can be eliminated if Cl ble of bidirectional communications Corner" for more about this subject. 0 and R2 are connected directly to pin 2 of +9Y the 741. For maximum sensitivity, increase the value of R2 from one to ten megohms and use a crystal microphone with a large R5 - diaphragm such as the Radio Shack Model /I< 270-095. The miniature crystal micro- phones sold by many parts suppliers will also work, but they generate less output. CZ If you prefer, fixed resistors R5 and R7 + R6 and potentiometer R6 can be replaced with XTRL Sok two fixed resistors after R6 has been M /C .ZNZZ-ZZI ¿,N 39054/ adjusted for best transmitted voice quality. +9V ETC. Disconnect R5 from +9 volts and R7 from ground, measure the resistance between R3 R,! the wiper of R6 and the disconnected ends S.6k S,6K of R5 and R7, and substitute fixed resistors having similar values. The transmitter works best with near - infrared emitting GaAs, GaAlAs and 4ie sEE -TEXT GaAs:Si LEDs. GaAsP red LEDs can also be used, but they emit considerably less optical power and therefore are best suited Fig. 1. Schematic of a light -wave voice transmitter. for optical fiber links. Whichever LED you select, it is impor- +9v tant to limit its forward current to a safe operating level. A reasonable range of quiescent current is from 10 to 40 milliamperes. High-level audio inputs will raise the current substantially. Resistor R8 determines the quiescent current, and its resistance should be 100 or more ohms. In my i SOLAR prototype, 330 ohms gave a stándby cur- CELL 1 I OR rent of 22 milliamperes. LEO For best results, insert a milliammeter 6 between the emitter of 01 and the LED's (OPTIONAL s PNOTO- cM386 + anode and substitute a 1000 -ohm potenti- TR.INS16TR) cz1 'y 22OrF ometer for R8. Adjust the potentiometer 9n until the desired current level is achieved. SPKR Then remove the pot, measure its resistance, and replace it with a fixed resistor. L SEE TEXT The Receiver. The light -wave receiver, which is shown in Fig. 2, consists of a 741 operated as a preamplifier and an LM386 Fig. 2. A light -wave receiver to go with the transmitter.

MAY 1980 103

AmericanRadioHistory.Com POBOX401244P_ ÇiUL GARLAND TEXAS for those who are getting or merely thinking of LEI 75040 getting started in mobile ,radio servicing. la cIr.lIcs Starting with a chapter devoted to servicing SE 0/ Saud E::'L«eda 17.50 requirements, the book goes on to detail The SE -01 is a complete Mt that required licenses, skills, and contains all the parts to build a technical test 1 programmable sound a is generator. Designed around equipment required; equipment inspection; 5 a r 1+ Me new Texas Instruments performance measurements; and alignment j pt sN76477 Sound Chip. the 1 r board provides Danks of MINI and tuneup. The last two chapters are e DIP switches veer; program tnc ousotcon,° devoted to troubleshooting and field servic- ate. binatiVCC).ON Se ShoOsct.a ;r En peso.Noofte, One Snot. and ( ing. The book closes with a glossary of terms ^iicej' Envelopes Ito AOuam Op Electronics Library Amp IC Is used to implement commonly used in mobile radio. 1 f tii an Adjustable Pulse Genera- tor. Level Comparator and Published by Howard W. Sams & Co., 4300 iilli Multiplex OOscillator r for even itL Bversatility The t x 5e West 62 St., Indianapolis, IN 46268. Soft cov- a Board a area to avow roer er. 144 pages. $4.95. circuitry caty programmed HANDBOOK OF AUDIO CIRCUIT DESIGN f 4 to duplicateExplosions. Phsor Guns, StearnTrains. or by Derek Cameron 61 / almost an ¡Monde number of r TOWERS' INTERNATIONAL OP AMP - other sounds. The unit has Bridging the gap between theory and basic multiple of applications The LINEAR -IC SELECTOR price includes all parts, design practices in audio, this book is written assembly manual. programming cnarts. and detailed 76r77 chip spool. by T.D. & N.S. Towers 4 I cations. It runs on a 9v battery (not included) On board I00Mw amp for the reader who has completed a course in

I drive a small speaker directly. or the unit can be connected to your stereo with incredible results) (Speaker not included). basic electronics. It begins with an overview of basic design principles and This handy reference book lists important 15 INCLUDED. EXTRA CHIPS $2.95 EACH proceeds 76477 CHIP electrical and mechanical specifications and 517.50 LESS SPEAKER & BATTERY through the principles of general audio-circuit design and then into amplifier planning and substitutes for almost 4500 domestic and for- From T.I.: TL490 BAR/DOT DRIVER IC. Drives 10 eign linear ICs. It begins with a general intro- LED's with adjustable analog steps. Units are implementation. Important coverage includes cascadable up to 10 (100 steps). Drives LED's directly. both positive- and negative -feedback, bias duction to basic op -amp theory, followed by Great for voltage, current, or audio displays. Similar in tabulated listings of the devices. Seven with specs and circuit notes. stabilization, and output arrangements. features to LM3914 appendices are included. The first four 2.95 Published by Reston Publ. Co., Inc., Reston, VA 22090. Hard cover. 225 pages. $17.95. explain tabulation coding, op -amp terms, NE IiI manufacturer codes, and manufacturer house II1II! numbers. The final three appendices contain MOBILE RADIO SERVICING MADE EASY tabulation codes for device applications, AY 3.8910 G. Sands an9 by Leo case outlines and pinouts, and codes for Servicing two-way mobile radio equipment pinout connections. A good one -source refer - can be a lucrative pursuit, but only if you know erice book for op amps and other linear ICs what you are doing. This book can get you with op -amp characteristics. tweet , ". started. Its seven clearly and concisely writ- Published by Tab Books, Blue Ridge Summit, ten contain a wealth of information PA 17214. Soft cover. 190 cages. AY3-8910 PROGRAMMABLE SOUND GENERATOR r chapters $7.95. The AY3-8910 is a 40 pin LSI chip with three oscillators, three amplitude controls, programmable noise generator, three r mixers, an envelope generator, and three D/A converters that are controlled by 8 BIT WORDS No external pots or caps required. This chip hooked to an 8 bit microprocessor chip or Buss 18080. Z80. 6800 etc.) can be software controlled to produce almost any sound. It will play three note chords, make HOBBY WORLD® bangs, whistles, sirens. gunshots, explosions. bleets. whines, or grunts. In addition, it has provisions to control its own memory chips with two lO ports. The chip requires x5V 75ma and a standard TTL clock oscillator. A truly incredible circuit. ELEcTRONICS l41 514.95 W/Basic Spec Sheet (4 pages) 60 page manual with S-100 interface instructions a0d several programming examples. $3.00 extra i A 19511 Business Ctr. Dr. Dept P5 ASSORTMENT A mix of new. panel mount 3/8" bushing pots in various values Some dual. Aim Northridge, Co. 91324 4POTENTIOMETERsome with switches ( 10/2.00 1/2W RESISTOR ASSORTMENT u good mix of 5%and 10°6 values m both foil lead end PC lead devices All --orir SEND FOR FREE new, first quality

7 (Asst 1200 pieces 2.00 SLIDE SWITCH ASSORTMENT FLYER FEATURING: I An outstanding includes m nature and standard sizes and mu0i- 1 \/ position units All newnrsiqualny. name brand Try onepavk and 4 you'll reorder more SPECIAL - 12 tot 5t 20(Aslcnes(Assortment) Page after page of exciting products. Com- (1 7 WATT AUOIO AMP KIT PARTS Son, SINGLE NvaR,D IC AND puterized toys and games, personal com- COMPONENTS en ON A 2 . PO ROAR(' IINCLUDEDI RUNS On 12YDC GROAT FOR OP301 AMPMV LLEo CAN PROJECT NAT NEEDS AN puters, disk drives, integrated circuits, 723 VOLT REG. 10 cosCAx LE, f APENSWE AMP LESS n5N T TKO g 5 723 IA PIN tSSCOMPTreLE WahlWahlSE Oi SOUND PETDINPUT 7r I.IP W. sT is semiconductors. Add new dimension to your 001102 Isv COMPUTER GRADE VIM TUNES SYNTHESIZER wrSPE[s NT The AYa-1150 h a MOs micrdcxmpuler Apple, Atari, TRS-80, etc. with our special ap- L11310 2w AUDIO IC wisescs 109 syntrie,eer of preprogrammed tunes In, Mo wrseecs a0evl,r names ini toys. music boxes. and uan MrloRTON MP or Standard deice has a plication boards and comprehensive software 1 1.11324 D PP MP 55 set of 25 diemenl popular and IA chimeMa s T REG IA 35v aing I f 25 tunes library. Hundreds of products available at ter- ISOLATOR FEATURES 71 OUALGATE MOSEET Minimal external components PROTECTED. SIMnAR Aulomalic swath -on signal at end of rific HOBBYWORLD prices. tune for power saving o PEP 3s Envelope Control to give organ or 1.148 R.CeP DIODE i Piano guantynt Our line of name brand include: ATARI, an .13 NOE. pl. RATIO AS Sequential tune mode products 1.003 IA 2.13v DIODE 11/1.00 door capability when used as door EXIDY, COMPUCOLOR, MATTEL, COLECO, VI DO nre MCvsiP OP d. DISC RIC 50 Operation won tunes en externs open08) ENTEX, FIDELITY, CALIFORNIA COMPUTER iaoicTrs,TEMis-MOUSE NUNsEREp Trun supplys Tune include STAR SYSTEMS and more, more, more. Circle our reader BEETHOVEN'S 9th a 6th. JINGLELE LEN'S SPANS. YANKEE DOODLE, STAR service number or write/phone for your free il- SPANGLED .E EN SE. '..°::11::" Val GOD SOLE lustrated flyer today! MIS, WEST MINISTER CHIME and M pRocreivow is DESCENDING OCTAVE CHIME 41 WOOL. LED PLUS MANY MORE. Two COLON RED WIN .59 NOEEDSPECSUR S14.50 11 /'ND INSTRUCTIONR all Toll -free: USA (800) 423-5387 1 NO C.O D.'s SEND CHECK M.O. OR CHARGE CARD NO. In Calif: 382-3651 PHONE ORDERS ACCEPTED ON (800) VISA AND MASTERCHARGE ONLY (214) 278-3553 Local & Outside USA: (213) 886-9200 ( ADD 5% FOR 'SHIPPING

1 TX RES ADD 5% STATE SALES TAX ` FOREIGN ORDERS ADD 100% (EXCEPT CANADA) Your #1 Mail -Order Computer Store! 1 120% AIRMAIL) U.S. FUNDS ONLY

CIRCLE NO 32 ON FREE INFORMATION CARD 104 POPULAR ELECTRONICS

AmericanRadioHistory.Com TOW.' * CORPORATION 00-34á-5144 Electronic Components ...... Quality. FREE , MN., AK., HI. RESIDENT4 ,218-681-6674 *. DON'T *, I.C.'S RESISTORS TRANSISTORS CAPACITORS DIODES I.C. SOCKETS & PINS SWITCHES 11 FORGET 6OUR - " JJI *I TESTING DEVICES DRAFTING SUPPLIES *1 DISCOUNTS'WHN COMPARING PRICES CLOCK MODULES OPTOELECTRONICS BREADBOADING & * DATA BOOKS s HEAT SINKS WIRE TOOLS ... AND MORE ... WRITE FOR FREE CATALOG * TEXAS INSTRUMENTS TIME -TEMPERATURE INTEGRATED CIPLCUITS SILICON TRANSISTORS PANASONIC IiRCTROLTI IC CA PAPA *r A55. -klTyy(6RI.C'- 1_IP- 4000 496016112405 43462 la -05P _PROGRAMMABLE MODULE lee I lO 1.C. SOCKETS ...1.80 16.50 150.00 1:00 00 4036 1 10 I0: ti 40^N 115015 .3 00 .31 ^O8e 11 5EN .17 1.03 9.53 - 190 '71.6 USER PROGRAMMABLE FOR: N324L°i05< 20 1.19 16.25 1-6.x5 .. .I) :a0 N 741_50211 1/WV 17 I.oJ 9.91 .11 1..10 íl.40 * SOlOEºT A IL DIP SOCKETS 2uooe .79 16.05 159.35 0, o W. 14034 .3.3 7415035 .3. -006 I.á U751214i 3:ié '7 IOJ .1/ 190 11.611 r 2124 7' 1.03 11.50 15,.50 2.2 504 n,wx . - 1.:0 11.6F f. C . w.. r...6, v.a .35 415046 .3 007 643937 1.40' 3.3,101. 1 1.03 Ili9.53 ".1) Eu126 ' 201 16.2`5 15.x5 WIZ .14 1.15056 000 1.12143966 190 67á5Y. I03 11.53 .31 4.5 11.67 1' 1.93 11.50 5 . I ISLW * o_ G9 15086 .3 0m .5- 196 198' 114401 2,1906. I OD O,a .10 Lev 14.07'. al - 93 11,50 151 W .41 .5. 37419 .16 164403 : 104966.. 1.03 1193 .n 1.40 49.24 ,,,,/¡¡rrrIJJJ1 .3 .36 :.70 2430 1 i0iú 11651040Ni 011 [I 499.6 l0 3sv.. i 1 m es3 .v Lao 49.64 * 66.1144 .37 4151111 . 4012 076 :eBl 24/5087 : :.70 .00 160.00 10 35V.. 1.09 0.08 .10 1.<9 14.071 009 .37 7415120 .36 7174111 013 .00 P15090 ]4 2.10 20.50 I p0 00 10 504. . 5 1.25 10.42 .13 1.91 15.671

. v0' ,4749 .35 7451396 JN .50 01e 1.0 265110 $7 1.45 n.50 2m 50 10 164.. ' 1 I.m 0.08 .70 1.69 14.0F' * ('O3Yd,1,.MP4x9r.rN.a.1 70109 1.35 01s 10 254.. 13 I.m 9.08 .n 1.71 1199 ' 1 ñ,6s1 s4 .65 0J.01 394.88 s 111004.95110TINx1.100461, , 74116 :61w41' 14w56 .38 016 °.5 I11 72 3$4.. I.4B 12.33 .n 1.01 15.87) 9xrP01 33 3.42- 30.66 ]77.00 INLAYSIIID[RTAIL 20411 91 7415216 .38 -017 1.0+ Np 1 16 1]65 1e 321 le39 .2t,' 91PU10 10 3.47 30.8: n9V 141)5 .41 7415006 .38 019 .0 IBN b 3JII6V.. 1.16 o:W .20 1.69 11.0T 9xNN5A 1 ] e9 33.3: 8x .. )4 '. )tl041 -019 .5 LKt7P42.5 35/35v I I la 911 .23 1,91 1167' _ 10 - 1.42 I. 74236 .3 7.102256bx 030 1,31N32012.d /1 OxNl51e JOeI' 1)),110 337N.. l9 1:61 1140 .n 331 12.39 .5.1. 4.ad * .. "ef53 "7290 .3 413279 'b 5,0[ Ja0NR6 .1 ,CrNSs 13.48 1:1.K1 lIm]5 1.71 14,34 .30 257 2135 6Ltt x1N.. r>.. ml 'I ll WV.. T .3 ),153BN b!y¡} 1.0: N1a0N2.0 )4 14.01 G 11 1.76 00 ,.h`14" ':1aaeN MIFI>a. p.m 00.13 511.1J 47 10V.. ] 1,11 3,n .a0 1.69 .31 . , 3 ,) 14 ©GN1 ñ 1im " ' ''.1aa1N 11305 2VM-11 ,AIF747 ) 646 58.5Tr s7e.W. 47 164.. ; 1.25 10.42 .23 1.91 15.e7' S 741531n 14 Gs» FEATURES _716 .3 .4 r.15 JEl4J: 4.80 40,04 60.00 47 254.. 1.25 10.41 ]e 1.24 13d' * may , .37 415376 .3 )1, 4)35V.. 1,73 14.34 )I tü n.o3 N4Ju 6.12 55.2: 40L25 : s] n ...,6aru0myxrn,al.r - 91 )415)06 3 ). I .14 AW.7 .)a 4) 1.x4 15.78 2.00 24.12yI - ii-mL.m,.-''u0.ru.. I2,-.1e 650.Ba SOV.. .6 *13)4 ^° ]] i:ef )1)Bx 91 14W09 ..018 .00 98. 1,8 1092 1.03 Is.B)3 22 4N allí ro 100 1w, !1 .1I - M73n 0.00 893e Ba.30 . .4.1.41...' in.. N., 1132x . :0s 9z 1441 ». . ' r «, w,. On I.I9 21N ,. 100 16V IJ.40 76 2N 7.eo 001.13 INLAY 30L0lRTIL ` `144pN .32 )4W)H I.O9 OW . SN ,1If570 ).)4 p9.6, e28.80 1 1,61 13.40 .31 2.65 10.05' t 4.9..0..MAsw.i.w91o,.xr,r-w 700 xSV. .(wL»,.nm.1.r...N.. ,.. . 1u14 .1371W89 1.0: r34 IÍ <1 MI671 - 1.7 e9,4: @6.80 1005sV. 4.04 15.28 Al 3ae 2e95 :.4;14.:4, ],{47031:71171.13 9.x,6x n - Fn-.+ w,+L,.prr.rab°,«,d..:<. 14459 .0374L5199 1.1. 035 5.1 a7x1579 17:10.17 67.1: 82431 1001104. 1.81 23.40 .3 34481 50.a 744.SN 1.0. 74ü51N .3. 040 1.2 67 8UE712 r , 11.i8 ae I0.50: * L,1r4i410Y Ioxu.xs+1u , r4l .Nhrr6,°.°n...rr.s.,o'c1 54 6.66 eo.l:s 541.I3 7201104. L74 26 a94 10. ,a : 74471 741569 .3. a1 1.0 .7 D3F)10 ,4 6.66 60.13 541,13 7201164, ¢47 N 1s 20 .71 7.34 10.55 3, 8.13 1.0 7K ©-1 r.i- 4e4.W.rw.ev,.,a.-re.. 74409 715556 . a2 1.0: ,üE00] .I 0Op e2.D)- ISeS) x10725v. 17,74 14:48 947 ,.íl a0,)s' .7496 .3 74613N 4' a3 4.0: 11 i4 7X:354. 3.m 25.70 .9 2:o14,1 ill); +. ::.n .x,6M.N..rn4M1w, 41 1.95 Is.M 405 00 10 14 .654,40 x.d.q.<..w,.,-..n.N49°..x:..a.4 4pL10 .31 SVKIJ LD I1.S1 167.00 330556. . 391 32 50 .6 Le1 619 NN,.ym 2eH1,x2.,i:C 7415a6N 7,1 57.11 ,3 ].pS33L -0'/ 270 m.50 180.00 ,S 6.41 53:33 .73 '6.19 21.01,0 `164 '' 37050., h4i:b.a.fin4N'',-. xR . m n , .e. 1a]5N 46905 057 I.I' 0r -IS l ppv3: " 3.A 70.50 IB0,00 47orev r 1.)3 14.77 .6 2.es 17,05 )4)SN e 3 w..].ry4n.m1),«s.rv 746036 '053 i.l' Or-IB 6.21156) 7 1.93 1730 157.50 70'IOV, 147 2.63 7237 .I7 5.57 A.4B <] ,476N + 7461019 5. OT.1a I y.4..1...r.w,areá ',p,rV1w.-r 'L 00001,..E .) ep13se5 7 193 V.W IS).W1roIeV. x.92 24.33 6m 37.1)r 143Jx .,:40 J1610ºN Oee '. 341P.5 ,a :' 3.m 25.70 s5 LR »,291 - K..,o n w11e6: '1 19] V.9 107.0g 47025V. .1) I. .4..,. .xl. ,ies9 .9 7.61129 on 1Pa .a. - 4ro 3sv. 4.99 40.n :wo 4..../.4/..14..101.477 HPat617 71 19] 17.9 ISLW . )111eN .1.74663N. g1 : 1P-e 470 WV. :.; 7.09 59.03 ÍSÓ .n4..4, iK ..,mi.wmeM.r.i.a..._ ...... :.::.: .iii 5213 393 '3 dQ'0 1.7 >16114H ml JS IP.10 0 :, 71 1730 IS)s0 1o001ev. x.34 10.60 97 4:06 33:34 4461' N.n w N,t.- 5116.... .n,..uala76. >)N I',1 3,10 x5.80 *'1(e.«¡.e;rv:.+i49Nwá::2 ax.Au]]r,,...'^50°°'°" )v1 :évi;l6sii3rwi IóJ -óéi ii irP:iS ó rwvi: ':i i:9m3 éi.9 is.w so°0°ooisév ': 3.15 31.1J si iéé á7i:° ,., 74917 r161a5N .e4 oev 1:7s 1P.4e n25,:1+. 2.48 1x.D 202.50 1 6.43 53.n .eo G.a1 se.vv, ° >,.,.1..L,4.114.L.r- +,4+ .r 7, 7000,25V * 70)N .57 11611dN .62 .76 9-74 .01 441,....,n...P-., nu,.r....wm.4 34 r] 'IP1147. 11.40 10.00' 6]0.00 .94 é.o0 6eA8: 0» ...-.....1Da..1re..u. ^.sa.~'M41.nwx4,0,°iy°..,yono., ,... 74054 -./1N61nH .9 ':OW a.m eN .ea 019 i100/év4 .. 4: Óé:V? 74051 .1' 761369 .40 /503 3N .52 3710/10V 3: 530 .13 11:]3 6Y:1' ..,..vvr 1 .hlr,.,.rr uvi70 ió:ii Vis 9195000 / ii *' a .. )Ilmx .)161JB5 .91 s10 .17 SOK E5 i'i 6.85 ee 1.9 e7Je NPIn. 16 1370 uD© 990.00 7200,16V ,' 5).m 1nM,;eG.b`ie]°5.115+rWexawI u 71095 067WJ9H e11su 32: SeH .,o 1300/a5V 8.64 74.48 1.11 944 73.611 w 7 ' : ` °""nww44Uu34""a~r'- ' 741216 .5 16 D tg121 16 13.70 110.0 990.00 .7 461516 771s12 13' [A61NfT.urOg 03441/T e á x ,rw ,ir. .... 1 3300164. I 5 ro 47.49 20 6.61 55.00; ;.r ,P1JT. 0 20.68 74127, .I1 161s1N 34 511 2.Br Ml)BN .Is- .-_-- :: Ip.L 19e.W 3300/IOV 4. 60l 6.02 .04 7,09 67.03 TIN PL11nw13EwxP r 6 ------74259 ---- 33501164 1 re y,a<+ !y ,11111: _Jf} * THE "PROGRAMMABLE" e1 161555 91151 1.a :DN.e IPa9C. [ 6.W A9 5T7.SD 3300,2áv 12.62 IDSn 1.6 I].17 1m.I0. N. 4..014.1.4 41329 .847 761565 91 i7 LV :1,, .31 W30C. 6.90 57,sD s17s0 4700,64, ).OV so.W .m O9I 10.N i :3 ]:NO CLOCK MODULE a419 1.1' 461579 .77 4519 °6 7 1Pmc. 11.5 70.® e3o.oD uronOV ';' 1.5 )o]s Ln IO.a *'111.114o: w.,. " L1 4745N .9 n6150, 86 520Al GP3x. 8.70 7259 651.W 4700,164 - 11.15 709.75 190 12.76 10637' USER ,})41UN 1] 7161Wx 1,) Yt-Pá-áé'64 PTiOGRAMM- L01 sn ' rlPelt. :.,,,oso SLD s1/W 6800/eV. m-35 70.15 I]I IO.Je ee.n * s as rv..aw:. ' II747186 3 7me111 t.m s1e v' - nPex.. eeoo5ov N n.n 93n ue n.e3 1os.asr á,m )4150N 1.1 I... _ -' r r»1N,..Y 1 -.? 461616 1 07 11 13 09 A¢ -Wr 61100116Y.._ .119 16.10 1)4.13 1151H 111'5 1.61 Ifl00N ] ., 16163N I01 s» n!1 o9.j7147 1255 507w .a.- I WIRfWR4PPINGWIRF 10.000,ev..ISe laso *E111l'..1"..1:2:.: °0-°^'- 11á]H .] /61615118 )3, 1.5 IN yo.aa05ov._ LEO Ie,10 111.84 nt6x 1.a1 3.61ee9 1.51 Ls le 1x PRE CUT - PRE STRIPPE ) 'á v .. r,' e.m /- .---- f. atssX 4151699 POLYESTER CAPACITORS x 1.51 lax PANASONIC ',t .r .--N{,¡wl.wr.vv 6R67o!a.ssNN[3TNu * , N OOlDIH1TwREwOA ,el Irr ']I15eN .]' 161Rp11.N J I.ON IWYr f 1"iNEMa . rxlW<,10,IOU[]x(! // ,.741574 .1 461739 1.34 14CO21 ]5 111 -Fl^-3L NMSM w4P6 . N . .72160N r79 . .0 461749 I. (a9 3 -.j irSv 044 I l C.,* . 19 104 ' II61N I.r.461759 )4COaN 3 291I 1 't5d* .35 lllell 0 7w31X 2 ,r51a2 743 11 95 n ]1:Fbmrawwl.y- Mi,n ii.rrr.-1.,v 41e71 9,a6100x Ib aO16 . 000N 0 EI,464x .0 7461070 1.35 4006 .35 005x o :E1 33 4e5x Lt 4wo2x Ll acJax 35 a0vx 4-o..x44-! 4 ila 11%00 16. 30.0...... 11 7sv It.;1Ó ie i:ii IM!á ñáá .-s-v 71. _..[Sss:as. . MF '741156 . :va .+L..ir..s-0rt1.y9 ..u.w<..r.»O6r^^rw°rrrn,w.r :eii15}iT1 i:i i()4M 14ó6X 1á.w '',7,,)6N K1301P ,10' ] w.,[" eo..,au..i. .. ,06,46a48,, MOLEX I C SULK' I PINS ....wrw..NO.mw6x.d,.....nxn 4,11C7 :1a MN xw 4 1774 .0. 462406 1.1 4CO3x 1.51 55v .ib.. M ,18DN . . /C_ EM S2rD'.00150M J x. m.-.ww..^ 1. . 4674JN 1.0 r4C81 1.s1 356A 1.07 ]I7 4.7,44111/14/3. ' I71elx 7 3 .62sJ11 .e .CBeH e e J.2a 1.31 nx * * Tg)(1A INSTRUMENTS GOLD 41026 I 11 r46250N 9 4(309 1 74 .5A n-Nr'q 741816 a3. 462eox .5 4036 ul ..v Isg ' 1'° N * EDGEBOARDCONNE:7'RS ,6y,ºe,+.:pir.uµn:.a ....,.,,741151 3,3 .115.r, .N 1]3.- Mm a.N4 17e']s .1IPR'6E A .9111LSb1N .61 4CI8111.1 .n r:11m]f ^?M.P 01°f ¡l panosonicTrlrNentlOmeters ú:rt' b 741086 laJa56eX .61r4C161N1.1 ')WKU .n . r..1...,1w. . ' ' Seldr 1 .4102 a4<0 ]4.» .i.w..-.r...wio7r 1109M 1974586N .55 40165611' -te10N .a)' ,7W' - Sola.rE i 17 * Y ..yyxp50rMaN,. i<: M iá 71731N 1.12745)U4 f.59r4C,)3N13 A7812W .n, .u.Ir.r:.r.,eaii . ñ1 '.7rnill,]4 AC'a3101Cd... 1 ,50 4C%í41 UA7We(U I,JOP 0415 1afERa3.100"a.200"LDGEeOlOCONNECTORS .4400 ].7o Hm * A[a111CC1... 1ís0 4C926X).e UA)00GCU IJ , a, ,] I.ei (3a7N1. uA)vlxv 1.)r e.` l Is yN LI I'. Decoeoaa... 1:224<2.,':r;' 7040 7,06 (;.la :149 ,IÑ ,56.01 aoel(N... 1.37 74(91897, u47v15CU 110 APANASONICTRIMMlRPOTENTIOMf[ERS ]] ¡. {7 1:.;. ,fineio 6N ?SS 0.0 LF _ y 6W6nIN ].ve sN e uarole(U Lro' .1,;10:111446.30101.1111%9114.11.4912,12.u'u..10u n n iU 1117 r.1/ m 0.17 ] -- p-ñ11v.5ooliE pN :e Lam.. Lee Y-.. [,1[11[ErS,y4. 9.` I 4' .I] . 16 ]N .0. 800929 e ,w9... x-46 ..1/.r. 19 1. '... 146 <] y.0 250 áa [rslDT , * 4m 3N 0.» á ñ , 7' y _ eocveN -- swa ' iáes , ,:11 $1-9" [unrav 1,'06 12/44 n14. in ru .r7rt1(1 2.40 443 160 CO n,.N 01452 503 n Ill 75 00 00 NS 00 yd6, :'" w40 , ' 2 rrn 2>: ó7i 'H i A 57° CARBON FILM RESISTO w.éo-"iDss.. ::90011:: ;' m aso 6.5 . 4o n 32 RE T R 31SSORTMEN-i ,yj¡1'r, .éó' .,. 'n yyyy m 31.a Y** `ms°N 00 C3.f, . WATT I:ii elizx4 i is .80 2.0 143 4» 3. 4.,h _ . lim: !.n 811eN 12s' a' n ii0é µ yr< pp..»mNN44 -_ eo... o! ;y 070e If A 8221N l.}" 504 37 m 140 00 S..)5aldñ. 11 .9'1' m34 40154 111 Cm :.:21.11 0151--. '90 13am 613 ,° 3'9d9'Í i i 7-11 54119 .65 á n á.00 . . 'i 79, áá 1151M :.I 9a69 611 6p RS115 : ,.x.,:¡:ió.`xP4M4`.n:''.;dpi. 1'S990 54529 71-00 13 5 35 4412 47 peox:o.,: 5990 54915 84 ,wo4,]106....,..].m..].2"]11 s:7 - 3 145_ 73.14 f. , )KS)IN 54979 1auNl[I i.s35,.330'[l]GEeoR000NNECTORS . y y1TAnRE51STOR54550RTMENTs 57 'ei 1 PLESTT MCIIBOR METALLIZED POI TESTER '- PANASONIC RESIN [ZIPPED TANTALUM I© I res ACCEPTS - - 54049 7:ói CAPACITORS CAPACITORS REilr7»1'ñ 1116 7 .N,.,,1... pw Iwl- - '- :1»x11 M45Eºi»A4,[, VISA. CODS. 11930 1.17 17 15/10 LIS 49x.7 zc. { MONEYC ASRS 1.17 IN. 7150 306 5.,.,5 4.5-1D .f. 1.3. 1.6 I/ ^ 10 104 164 ° ' ia.d..0 8 JfW50901330 I. 5004 31 110 N0C' 1. O,d.r.«.P,.d.yPnoxoorMall 01 4 33 NARD'WAPE Chock 05404 N .. M 0-'e 25 COD Mon, ra..-I] S111COduWULS 1vm P. º: ' 21 t 1.SeIr15CwFW...I. y/ 7}ser Y5021 rS I du19OrDaTaBOO P.o. e..n.anLEºL.fau..Mlnn.se7os 500V 3 46 45 Se Bd ff qq dY - °°O1mi ^`"' ...Car.. L - ro3 eo i.a 16ar '1-40117SCRFW 'wlf i S» 4 4d7 eaal7xREw .;.-tt1ó iM003 so 3.W a ., WM 5 se 1,1112"' -;i" Drl@ b IÓÓ l e -3x 3B scTFw 'i.39 c 161W5 5'.W 100 9.00 1.152 Y 11/0 AO 470 : 83as//exRFw::.0.' /C II.Oa N.4i.r'ten3á: KE.Y 100 9.06 IN1001 sw a1eNF[NUr 1 C . DIGI epa , á f1 I15 ... 113,N 1., r. . X 35 7.1 -h. N' L.32 14114 CORPORATION .0141. 504 Al 4 19 5 11iá.1*11.x n.- x..+ - FM . ssoc r 131 NUT - LIDS SWITCHES R. . u° ]W I 1 _ GAO N, . rxo.11oc[wAsxE[ Y.xsif á0 .1 .I....,.,r.1,:,n....o, N...... N ji L 0nn QZ{alFl1 MSC Components 16.W C :awx...-N6.r .sd...11.4.N521:41632 0.1lOCJ(W45NEP 1.00/C ' Electronic 'ten a0 I.[D/10 o'r.' i.. 2W w 1w »m W.1. , N0.6LOCIIW45N{ 1.00IC V50v.10 le.e1 c 1/1 1 4»- P 0. Ros 677 Thief River F011s, MN 5A70í (118) 681.6674 Loso 4'.:' ' rr . nao 11fi 611 60.elOawAw °_OOUc , ...... a Rn' LidnsNie....,-1-v1.-..+(..rx.lmrE.- . o. r. r .11 LO710 IO.arC.

---4.. 0. * * * * * * * * * * * * * * * * * * * * * * * * * * 7r 1 * * * * - * *I.': * * m* * * * * * * * * © NS11(i CIRCLE NO.18ON FREE INFORMATION CARD AmericanRadioHistory.Com TELEPHONE/KEYBOARD CHIPS 7400 TTL AV.5/1100 Puss Button TolellEOne Dialler 514.95 5N7470N .29 AY -5.9200 Repertory Dialler 14.95 TIM Cromemco AV -5.9500 CMOS Clock Generator 4.95 5N7472N .29 Incorporated AV -5.2376 Keyboard Encoder 88 keys 14.95 5N7400N .20 5N7473N .35 5N74160N .89 HD0165 Keyboard Encoder 16 keys 7.95 SN7401N .20 5N7474N .35 SN74161N .89 74C922 Keyboard Encoder IS keys 7.95 SN7402N .20 5N7475N .49 SN74162N 1.95 Z80-4MHz Single Card Computer 74C923 Keyboard Encoder 20 keys 6.25 SN7403N .20 5N7476N .39 SN74163N .89 SN7404N .25 5N7479N 5.00 SN74164N .89 e,.....:. sue dwe e..a..., k. eD.Dien ee4e.u,,.8. ee,e,.n. ICM CHIPS ..M. al Om 1W M n,. m,e.elry .I me LIDO e.. re the d.eenee o... ICM7045 SN7405N .20 5N7480N .50 SN74165N .89 CMOS Precision Timer 24.95 SN7406N .29 5N7482N .99 SN74166N 1.25 ICM7205 CMOS LEO Stopwatch/Timer 19.95 The Ma e.4 MN, nw.unFeN bMs m u e...4 U16 redM. w le ICM7207 SN7407N .29 5N7483N .69 5N74161N 1.95 Osdllator Controller 7.50 lone cad AM advaIM an RS 232 ICM7208 Seven Decade Counter SN1408N .20 5N1485N .89 5N74170N 1.59 url wewira 19.95 . rIMM ICM7209 Clock Generator SN7409N .20 5N7486N .35 SN74112N 6.00 nAoo...1 luoW e S ad 6.95 SN7410N .18 5N7489N 1.75 SN74173N 1.8 men.. The s é SUM READ SN7411N .25 5N7490N .45 c.. NMOS ONLY MEMORIES SN74174N 1.00 The Mower w[enn.i a46iC are ne4.W L.wu I RUnreeaM MCM6571 128 X 9 X 7 ASCII Shifted with Greek 13.50 5N7412N .25 5N7491N .59 5N74115N 1.00 M41 2161. a44aler MCM6574 128 X 9 X 7 Math Pictures SN7413N .40 5N7492N .43 SN74116N .79 Symbol 8 13.50 MCM6575 128 X X 7 Alpha SN74I4N .70 5N7441N .43 SN74I77N .79 SCC'W (Alserwnleal $450.00 9 Control Chan.Gen 13.50 SN7416N .25 5N7494N .65 SN74179N 1.95 MISCELLANEOUS 5N7411N .25 5N7495N .65 5N74180N .79 "01~s RS ad,/ mao ma Cal Rumenmada TL074CN Ouad Low Nose hi -let Amp SN7420N .20 5N7496N .65 SN71181N 1.95 Op 2.49 TL494CN Switching Regulator 4.49 SN742IN .29 5N7497N 3.00 5N74182N .79 TL496CP Switching 1.75 SN7422N .39 5N74100N 1.25 SN74184N 1.95 weT ham sw, e., R100 Single Regulator 11C90 Divide 10/11 Prescaler 19.95 SN7423N .25 5N74107N .35 5f474185N 1.95 95H90 HI -Speed Divide 10/11 Preslaler 11,95 SN7425N .29 5N741031N .59 SN16186N 9.95 RAM I' Sum 4533 Photo -Darlington Opto SN7426N .29 SN74116N 1.95 SN74188N 3.95 -Isolator 3.95 MK50240 Top Octave Freq. 17.50 5N7427N .25 5N74121N .35 SN74190N 1.25 Generator DS0026CH 5Mhz 2 -phase MOS driver 3.75 SN7429N .39 SN74122N 39 SN74191N 1.25 clock TIL308 27' red num. 5N7430N .20 5N74123N .59 SN74192N .79 DISCRETE display wdnteg. logic chip 10.95 .25 ale- MM5320 TV Camera Sync. Generator 14.95 SN7432N SN74125N .49 5N74193N .79 XC556R .200" 5/51 MV50 MM5330 415 is 5N7437N .25 5N74126N .49 5N74194N .89 red .085" red 6/Sl XCIIIR .190" red 5/51 Digit DPM Lo Block (Special) 3.95. XC556G .200" 4/51 L0110/111 A/D SN743eN .40 5N34132N .75 5N74195N .69 green XC209R .125" red 5/$I XCIl1G .190" green 4/51 344 D101í Converter Set 25.00/set XC5567 .200" 4/Sl XC2090 64c 5N7439N .25 5N74136N .75 531741960 .89 yellow .125" green 4/SI XCIIIY :190" yellow 4/51 14433P 344 Digit A/D Convener 13.95 XC556C .200" clear 4/51 XC209V .15" yellow 4/Sl XCI11C .190" clear 4/51 SN7440N .20 SN74141N .79 SN74197N .89 SN XC22R .200" LITRONIX ISO 1 76477 5N7441N .89 5N74142N 2.95 SN74198N 1.49 red 5/SI XC526R .185" red 5/51 -LIT XC22G .200" 4/51 XC526G .185" 4/51 SOUND GENERATOR 5N7442N .59 5N74143N 2.95 SN74199N 1.49 green green Photo Transistor Opto -Isolator XC22V .200" 4/51 SN7443N .75 SN74144N 2.95 SN745200 4.95 yellow XC526Y .185" yellow 4/$I INFRA -RED LED (Same as MCT 2 or 41425) Generates Complex Sounds MVIOB .170" red 4/SI 4/51 5N7444N .75 5N/4145N .79 SN74251N .99 XC526C .185" clear N"xW"01/16"flat 5/Sl Low Power - Programmable SN7445N .15 SN74I47N 1.95 SN74279N .19 494i each $3.95 each SN7446N .69 5N74148N 1.29 SN74283N 2.25 DISPLAY LEDS SN7447N .59 SN74150N 1.25 SN74284N 3.95 TV GAME CHIP AND CRYSTAL TYPE POLARITY HT PRICE TYPE POLARITY HT PRICE SN7448N .79 5N14151N .59 SN74285N 3.95 8. stal SN7450N .20 .59 MAN 1 Common MCde.red .270 2.95 MAN 6730 Common Mode.red _ I .56D .99 í1c SN74152N SN74355N .69 includes Osccore display. 6 and 4 4.95 games select angles. etc. 5N745IN .20 5N74153N .59 SN74366N .69 MAN 2 5 7 001 Alatdx-red .300 MAN 8740 Common Calnode.red-D,O. .560 99 7. 95/Set MAN3 Common Cathode -red .125 .25 MAN 1 SN7A53N .20 5N74154N 1.50 5N74367N 69 6750 Common Cathode -red e .560 .99 X6205 58,40 XR2242CP 1.50 MAN 4 Calhode.red SN7A54N .20 5N74155N .79 SN14368N .69 Common .187 1.95 MAN 6760 Common Anode-red .560 .99 08210 4.40 X82264 4.25 MAN 7G Common Anode.gteen 300 1.25 MAN 6780 Calnodered .560 .99 5N1459A .25 SN74156N .79 5N7490N 1.95 Common X8215 4.40 EXAR 082556 3.20 MAN 77 Common MOde.yenow .300 .99 31707 Anode -red _ 1 .300 SN7460N .20 5N74157N .65 SN7493N 1.95 Common .99 59320 1.55 082567 2.99 MAN 72 Anode -red .75 Common .300 01704 Common Ginode.red .300 .99 XR-L555 1.50 JE2206KB 19.95 X83403 1.25 MAN 7 Common Cathode -red .300 1.25 31707 Anode CD4000 .39 C 0407 .55 Common -red ,300 .99 X6555 .39 001800 3.20 984136 1.25 MAN 82 Common Anode yellow .300 479 31728 Cathode 149 CD4001 .39 CMOS CD4571 .49 Common -red 500 X8556 .99 082206 4.40 X84151 3.95 MAN 84 Common Cathode -yellow .300 .99 01741 Common Anade.ed .600 1.5 C 04002 .39 C 04028 .89 C04072 .49 XR567CP .99 X192207 3.85 X84194 4.95 MAN 3620 Anode -orange .300 .49 01746 Anode I 1.49 C04006 1.19 C D4029 1.49 CD4076 1.9 Common Common -redo .630 XR567CT 1.25 082208 5.20 X84202 3.60 MAN 3530 Common Anode-orange m 1 .300 .99 0747 Anode -red 149 C D4007 .25 C 04030 .49 CD4081 .39 Common .600 XR1310P 1.95 X62209 1.75 984212 2.05 MAN 3640 Common Cathode -orange .300 99 01749 Common Colhode-red e I .630 1.49 C 04009 .49 C04035 .99 C 0408 .39 XR1468CN 3.85 082211 5.25 094558 .75 MAN 4610 Common Mode -orange 0L750 C D4010 .49 CD4040 1.49 CD4093 .99 300 .99 Commas Cathode-red .600 1.49 081488 1.95 X92212 4,35 094739 1.15 MAN 4640 Common Cathode -orange .400 .99 01330 Cathode .11D CD4011 .39 C04011 1.49 CD4098 1.19 Common -red .35 X91489 1.95 082240 3.45 X94741 1.47 MAN 4710 Common Mode -red .400 .99 CD4012 C 04012 .99 MC14409 14.95 8070 Common Cathode 250 .69 .5 VOLTS MAN 4130 Common Anode -red _ I .400 99 F5D35E1 Common Cathode e 2 .357 .99 TYPE IV PRICE CD4013 .49 CD6043 .89 MC14610 16.95 DIODES PIA MAN 4740 Common Calnode-reo .400 .99 140359 Common Cathode .357 .75 1N4002 100 1 AMP 12/1 00 CD4014 1.39 C D4044 .89 MC14411 14.95 TYPE VOLTS w PRICE MAN 4810 Common Anode -yellow .400 600503 104003 200 PIV 1 AMP CD4015 1.19 CD4346 1.79 MC14419 4.95 .99 Common Cathode/{N0500) .500 .99 12/1.00 MAN 4840 Common Cathode -yellow .400 803507 Anode 1N746 3.3 400m 4/1.00 14481 400 PIV I AMP 12/1 00 CD4016 .59 CD4047 2.50 MC14433 13.95 .99 Common 00510) .500 .99 14751 5.1 4000 1/1.00 164005 600 PIV I C 134017 1.19 1.35 MAN 6610 Common Anode.oranae-0.0. .560 .99 5082.773 Common Anode -red .300 .99 AMP 1011 00 CD4D18 MC14506 .75 14752 4095n MAN 6630 Common Mode -orange _ 1 .560 99 161SP.3400 Anodered 5.6 4/1,00 149006 800 PIV I AMP 10 1 CO CD4018 .99 C 04319 49 MC14507 .99 Common .000 1.50 MAN 6640 99 0096.34 3 Cathode red .8D0 1N153 6.2 4000 a/1.0o 004007 1000 116 1 AMP 10100 CD4019 .49 CD4050 .69 MC14562 11.95 Common Cathode-oiange.D.D..560 Common 1.50 14751 400n - MAN 6650 Common Cathode -orange o 1 .560 5082.730 4 4 7 591. .600 6.8 4/1.00 153600 50 200. 6100 CD4020 1.19 CD4051 1.19 MC14583 2.49 .99 Digit.RHDP 19.95 MAN 6660 Anode -orange .99 4 4 7 SDI 14757 10 4000 a/1.00 164148 75 tom 15'1 CO CD4021 1.39 C D4053 1.19 C Common .560 5082.730 010-1.HDP 600 19.95 0450 3.95 15759 12.0 400m 4/1 00 194154 C 0402 1.19 C04056 2.95 CD4510 1.9 MAN 6680 Common Cathode -orange .560 .99 5082.730 Overrange character (_1) 600 15.00 35 Mm 12/1.00 MAN 6710 Anode-mA.O.D. .99 5082.7340 4 e 7 141959 8.2 400m a/1.00 154733 5.1 Ica 28 CD6023 .29 CD4059 9.95 CD4511 1.29 Common 560 SDI 0,D'r.He.adenmal 600 22.50 18965 15 4000 4/1.00 144734 5.6 to 28 CD4024 .79 C 04060 1.49 CD4515 2.95 145232 5.6 SOOm 28 154735 6.2 lw CD4025 .23 CD4066 .79 CD4518 1.23 CALCULATOR 28 RCA LINEAR CLOCK CHIPS 1N5234 6.2 500m 28 144736 6.8 tw 28 C04026 2.95 C04068 .39 C04520 1.29 CHIPS/DRIVERS MOTOROLA C A913T 2.15 CA3082N 165235 6.8 500m 28 154138 6.2 to 28 CD4o27 .69 CD4069 .45 CD4566 2.25 2.00 CA2023T 3.25 CA3083N 1.60 MM578 62.95 MM5309 4.95 MC1408L7 4.95 1N5236 7.5 5000 28 144742 12 lw 28 74C00 .39 74C00 740163 2.49 CA309T 2.48 CA3086N 85 MM5738 2.95 MM5311 4.95 MCI408L8 5.75 1145242 12 50061 28 1144744 15 lw 28 74002 .39 14C164 2.49 CA309T 1.35 CA3089N 3.5 DM8864 2.00 MM5312 4.95 MC149L 2.95 145245 15 5000 28 151183 5D Ply 35 AMP 1.60 1 40m 74C04 .45 7aC85 2.49 74C173 2.60 CA3046N 1.30 CA3130T 1.39 0638865 1.00 MM5314 4.95 MC3022P 2.95 N456 25 6/1.00 151184 100 P10 35 AMP 1.70 15458 74C08 49 74C90 1.95 74C192 2.49 CA3059N 3.25 CA3140T 1.25 DM88B7 .75 MM5316 6.95 MC3061P 3.50 150 7m 6/1.00 141185 150 Phi 35 AMP 1.70 154854 74010 .39 74C93 1.95 74C193 2.49 CA3060N 3.25 CA3160T 1.25 DM6889 .75 MM5318 9.95 MC1016(7441617.50 ISO 10m 5/1.00 110186 200 P135 AMP 180 154001 1 AMP 74014 1.95 74C95 1.95 740195 2.49 CA1080T 1.25 CA3401N .59 9374 7-seg. MM599 2.95 MC4024P 3.95 50 PIV 12/1.00 151188 400 PI0 35 AMP 3 00 74020 .9 14C107 1.5 740922 7.95 CA30B1N 2.00 CA3600N 3.50 LED driver 1.50 MM5381/1998a4.95 MC4040P 6.95 74C30 .39 740151 2.90 74C923 6.8 MM5309 4.95 CT 1001 6.95 MC4064P 4.50 SCR AND FW BRIDGE RECTIFIERS 74042 1.95 74C154 3.00 740925 8.95 0363 154 4.4006 SCR/2141849) 51.95 74048 2.49 74C157 2.15 740926 8.95 LOW PROFILE SO LDER TAIL C3614 354 6006 SCR 1.95 74C73 .89 74C160 2.49 80095 1.50 / 242328 1.6A 3006 SCR 7aC74 .89 7aC161 2.49 80C97 1.50 (TIN) SOCKETS STANDARD (TIN) 4 so MOO 980-I 12A 506 1-24 549 50-100 4 FYI BRIDGE REC. 1.95 18MG 1.75 LM710N .79 1-24 25-69 50-100 MU 980.3 12A in 2000 RV BRIDGE REC. 1.95 LMl06H .99 8 pin LP .17 .16 .15 LM711N .39 14 Pin ST .27 .25 24 LINEAR 14 Pin LP 20 .19 .14 LM30oH .80 LM723N/H .55 16 pin ST .30 27 C106B1 .so TRANSISTORS 253904 - 4/1 00 .35 16 pin LP .22 .21 .20 MPSA05 .30 LM301CN/H LM340K-18 1.35 LM733N 1.00 18 pin ST .35 .32 .30 243055 .89 243905 111 00 18 ele LP .29 .28 .21 MPSA06 LM302H .75 LM340K-24 1.35 LM739N 1.19 24 pin 511 49 .45 .42 5/1.00 MJE3055 1.00 293906 411 00 LM304H 20 pin LP .34 .32 .30 71597 611.00 1.00 LM340T3 1.25 LM7410N/H .9 28 pin ST .99 .90 .81 253392 5/1.00 204013 3/1 00 22 pin LP .37 .36 .35 11598 LM305H .60 LM340Tá 1.25 LM74I-14N .19 36 pin ST 1.39 126 6/1.00 253398 5/1.00 254123 611 00 24 pin LP .38 .37 .36 1.15 40409 LM307CN/H .35 LM340T-8 1.25 LM747N/H .79 .10 pin ST 1.59 1.75 P43567 3/1.00 P44249 1/1 00 28 pin LP 45 .44 .43 145 1.30 LM308CN/H 1.00 LM340T-12 1.25 LM748N/H .39 40410 1.75 P53568 4/1.00 P54250 4/1 00 36 pin LP .60 .59 .58 40673 LM309H 1.10 LM3401-15 1.25 LM1310N 1.95 1.75 P43569 4/1.00 2144400 4/1 00 40 pin LP .63 .62 .61 WIRE WRAP SOCKETS LM309K 1.25 LM340T-18 1.25 LM1458CN/H .59 25918 4/1.00 MP536384 5/1.00 244401 411 00 (GOLD) LEVEL 2/0.00 LM310CN 1.95 LM340T-24 1.25 MC1488N 1.95 #3 2022194 MP53102 5/1.00 254402 4.1 00 LM311N/H .90 LM358N 1.00 MC1489N 195 SOLDERTAIL (GOLD) 1-24 5-49 501.100 242221A 4/1.00 253704 511.00 244403 41Do LM312H 1.95 LM310111 1.95 2422224 5/1.00 5963704 LM1496N .95 STANDARD . B pin WW .59 .54 .49 5I1.00 264409 5200 LM317K 6.50 602222 Plasdc 7/1.00 LM373N 3.25 LM1556V 1.75 10 pin WW .69 .63 .58 243105 5/1.00 245086 4,1.00 LM318CN/H 1.50 4.00 1-24 50-100 2423694 4/1.00 4/1.00 LM377N MCI7415CP 100 5i9 14 pin WW 79 .73 .67 0793705 5/1.00 205087 LM319N 1.30 MPS2369 LM390N 1.25 LM2111N 1.95 8 Pin SG .9 .35 .31 16 pin WW .85 .11 .70 5/1.00 253706 5/100 245088 4/1.00 LM320K5 1.35 .99 242484 4/1.00 0753106 LM90CN LM2901N 2.95 14 Pin SG .49 .45 .41 18 pin WW 99 .90 .81 5/1,00 245089 4/1.00 LM320K-5.2 252906 6/1,00 1.35 LM91N 1.79 LM3053N 1.50 16 pin SG .54 .49 .44 20 pin WW 1.19 1.08 99 243707 5/1.00 745129 5/1.00 LM320K-12 1.25 LM382N 1.79 LM3065N 18 252907 511.00 253711 5/1.00 645134 5/1 00 149 pin SG -59 .53 , .48 22 pin WW 1.49 1.35 1.23 LM32014-15 1.35 NE501N 2417246 8.00 L1,3900N13401).59 24 pin SG 79 .75 .69 24 pin W W 1.39 1.26 1.14 .65 16.15138 53 00 LM320K-18 1.15 NE510A 6.00 LM3905N 1.49 28 Pin 5G 1.10 1.00 .90 28 pin WW 1.69 1.53 1.38 2N2925 5/1.00 2437254 1.00 255139 5/1 00 1.35 LM320K-24 NE529A 4:95 LM3909N 1.5 36 Pin 5G 1.65 1.40 1.26 36 WW MJE2955 1.25 253172 2.25 255210 5/1 00 LM320T-5 pin 2.19 1.99 1.79 1.5 NE531H/V 3.95 MC5558V .59 40 pin SG 1.5 1.59 1.45 40 pin WW 2.29 2.09 1.89 253053 2/1.00 20923 100 245419 3/1 00 LM320T-5.2 1.25 NE536T 6.00 8098 495 243903 5/1.00 255951 3/1 00 LM320T-8 1.25 NE540 6.00 LM75450N .49 LM3207-12 1.25 NE544N 4.95 75451C .39 LM720T-15 1.25 NE550N 1.30 75152Civ .9 1/4 WATT RESISTOR ASSORTMENTS 5200LIC000d1= CORNER LM323T18 1.8 NE555V .39 75453CN .39 -5%CAPACITOR 10 OHM 12 OHM 15 OHM 16 OHM 10 .05 LM3207-24 1.5 NE556N .99 75454CN .39 72 OHM pf .01 OJ .00loF .OS .035 ASST. 1 5 ea. OHM g 22 .05 .O3 LM323K-5 5.95 NE560B 5.00 75491C .19 27 33 OHM 39 040 14 OHM 56 0NM 50 PCS $1.75 DI .D/ .0047a.í .05 .04 .035 17 DI .05 .04 :03 .DIPF .05 04 .035 LM324N 1.49 NE5626 5.00 75A92CN .89 68 OHM 82 OHM 100 OHM í2O OHM 150 OHM 100 pr .OS .01 .03 .022657 .06 .05 04 LM339N .99 NE565N/H 1.5 75493N .89 ASST. 2 5 Co. 180 A 50 PCS OHM 770 ON 210 OHM 330 OHM 391/ OH%A 1.75 220 01 .OS .04 .03 .047 66 .06 .05 .01 LM340K-5 1.35 NE566CN 1.75 75494CN .89 ONrA 470 or .OS .01 .035 .12 .09 .075 410 560 OHM 680 OHM 820 ONZA Ix 1.M34011ó 1.35 NE567V/H .99 RC4136 1.25 0017 .007ÁR FILM CAPACITORS ASST. 3 5 ea. 1.20 1,54 1.60 2.76 2.74 50 1 LM340K-8 1.35 NESION 4.95 RC4151 3.95 PCS .75 .00101 .12100 .10 ,13 .11 .OB LM340K-12 1.35 LM703CN/H .69 RC4194 4.95 3.36 3.90 4.7e 564 6.84 0022 .12 .10 .07 .04701 .21 .11 .13 LM340K-15 1.35 LMI09N/H .29 RC4195 4.49 .004701 .12 .10 .07 .Iml .27 .17 ASST. 4 5 ea. 4.70 IOr. 120 156 lee 50 PCS 1 .75 .01 ml .12 .10 .07 .2201 .33 .2727 .22 74L500 74LSOOTTL 74L5179 1.05 220 276 330 396 170 4.20% DIPPED TANTALUMS 1501101 CAPACITORS .11356 74L501 .35 74L551 .29 74L5151 1.05 ASST. 5 5 ea. 561 680 820 1000 120( 50 PCS .41 .33 .26 1 .75 .15/356 74LS02 .35 741.554 .29 74L5155 .39 .31 .5 2.2/359 .51 .45 .31 1.8 1504 1808 720a1 2701 390 74LS03 .35 74L555 .29 74L5157 1.05 .22/350 .9 .31 .8 3.3/255 .53 .43 .34 ASST. 6 s ea 1904 4706 5606 6830 9296 50 PCS .33/359 .39 .31 .8 4.7256 .63 .51 .41 7aLSo1 A2 74L573 .54 7415160 1.15 1.75 .47/356 .39 .31 .25 6.8200 .79 .63 .50 74L505 .42 74L514 3.1 1.261 1.564 1.98 74L5161 1.39 2.2M .66/350 .39 .31 .5 15255 1.39 1.12 .89 74 L508 .35 14LS75 .554 ASST. 7 .OA .'4 4.10 1 .39 74LS162 1.8 5.610 50 PCS .75 1 095 .31 .5 22/6 V .79 .63 .50 741.509 74L576 .54 74L5163 1.39 MINIATURE ALUMINUM ELECTROLYTIC CAPACITORS .35 ASST. 8R Includes Resistor Assortments 1 -7 PCS.) S9.95 141.510 74L578 .49 74LS164 1.50 (350 ea. Axial lead Badlal 74 Lead L511 .75 74L583 1.05 74L5175 1.25 .41/509 .15 .13 .10 .47250 .15 13 $10.00 Min. Order - U.S. Funds Only Spec Sheets - 25f . .lo 74L513 .59 74LS85 1 .0 .16 .11 1.50 74LSIS1 2.49 Calif. Residents Add 6% Sales Tax 414 50V .14 .17/500 .16 .14 .11 74L514 1.5 71LS86 .54 74LSI90 1.39 1980 Catalog Available --Sens stamp 3.3/506 .14 .12 .09 1.01166 .15 .13 .10 74 L5I5 -35 74L590 .71 74LS191 1.39 Portage -Add 5% plus Sl Insurance (if desired) 4.7250 .15 .13 .10 1.0250 .16 .14 .11 74L520 ,35 74LS92 .90 74LS192 1.9 10256 .15 .13 .10 1.01500 .16 .14 11 74L521 .9 14L593 .90 74L5193 1.9 PHONE 10/50V .16 .14 .12 0.7/160 .05 .13 .10 22/250 .17 .15 .12 .15 74L522 .35 14L595 .99 74 L.5194 1.9 4.7250 .13 .10 ORDERS 22000 .24 .20 .18 6.7)500 .16 .16 .11 74L526 .35 74L596 1.15 7415195 1.39 47250 .19 .17 .15 10/166 .14 .12 741527 .35 14LS107 .54 741_553 WELCOME .09 1.5 47/506 .25 .21 .19 10250 .15 .13 .10 74 L528 -35 74LS109 .54 74L5257 1.05 (415) 1001250 .24 .20 .18 10/509 .16 74L530 .35 74L5112 592.8097 -14 .12 .54 74L5258 1.5 ELECTRONICS 100/500 .35 .30 .28 47/506 .24 .21 .I9 741.532 .42 14 LS123 1.50 741_5260 .83 Jameco 2201256 .32 .28 .25 100/166 .19 .15 .11 .45 74 L537 74 LS125 1.05 74L5279 .90 MAIL ORDER ELECTRONICS - WORLDWIDE 220/506 .45 .41 .38 100/250 .24 .20 .18 74LS40 .35 IaL5132 .99 74L5367 .15 1355 SHOBEWAY ROAD, BELMONT, CA 94002 470256 37 .29 27 100150/ .35 .30 28 74L541 1.05 741..5136 .59 74L5368 .75 1000 16V ,55 .50 .45 220/160 .23 .17 I6 141.541 1.05 74L5138 1.05 71LS670 2.49 5.80 PRICES SUBJECT TO CHANGE 2200 16V .70 .62 .55 470/250 .31 .28 z

106 MAY 1980

AmericanRadioHistory.Com MINIATURE SCREWDRIVER MICROPROCESSOR COMPONENTS The Incredible BO80A,8080A SUPPORT DEVICES MICROPROCESSOR MANUALS 8080A CPU S 7.95 103x41111 M -Z80 User Manual 57.50 "Pennywhistle 8212 8.911 Input/Output 3.25 M'CDP1E02 User Manual 7 50 8214 Priority Interrupt Control 5 95 M-2650 User Manual 5.00 434" 8216 &.Dinaonal Bus Driver 3.49 a RUGGED CONSTRUCTION 8224 Clock Generale/Omer 3.95 ROWS 8226 Bus Driver 3.49 $139.95 Kit Only _" 10001 OF USES- tin- TIP 2/61.00 Character Oeneratorlupper rase) 59.95 4.95 2513121401 8228 System Contr.:Per/8os Omer The Pennywhistle 103 r5 Capable el recording data to and` Iron audio tape without 2513(30211 Character ienerataglawer case) 9 95 8238 System Controller 5.95 speed requirements for the recorder and R is able to communicate erectly with 2516 Cnanctar Generator 1095 corset 8251 Prop. Comm. 121 (USART) 7.95 ancler modern and terminal for telephone "hamming' and CommunicaUOns In MAGNETIC RETRIEVER TOOL MM5230N 2048.Bit Read Only Memory 1 95 8253 ;Wog. Interval Timer 14.95 addition, ,t 65 tree of ennui adjustments and Is bulb with nOmpreeinon, readil.vaia11e 8255 Prog. Penph 110 (PM) 9 95 RAM'S caes. 8257 Prop. DMA Control 19.95 Data Transmission Method ..-.FrequencyShih Keying, full -duplex (hall.dupie. 1101 25681 Static S1 49 8259 Rog. Interrupt Control 19.95 setectable). 1103 102401 Dynamic .99 680016800 SUPPORT DEVICES Maximum Data Rate 300 Baud Picks up elusive metal parts or tools 2101(8101) 25604 Stabs 3.95 IIC6800 MRS 514.95 Dar. Former Asynchronous Serial (retina to mark level required in hard -to -reach places. 2102 102191 Static 1.75 kIC6802CP MPU with Clock and Ram 21,95 between each character) 21102 102461 Static 1.95 TO ROTATES UIC6810API 12888 Static Ram 5.95 Receive Channel Frequencies 2025 Hz for space. 2225 Hz for mark, EXTENDS 2634' - 360° 20111) 25684 Static 395 1,106821 Penph. Inter. Adapt (MC66969 7.49 Transmit Channel Frequencies , Switch selectable Low 1070 .Wee. STRONG, LIFETIME MAGNET 21121111 25594 Static MOS 4.95 (leO MC6828 Priority Interrupt Controller 12.95 1270 mad: High 025 space, 2275 mars 2114 102404 5ta9e 450ns 795 M R $3.95 MC683018 102408 81 ROM (8268030.6) 14,95 Receive Sensitivity -46 ebm accousr coupled. T-2281 21141 102484 Static 45Ons low prover 1095 MC6850 Asynchronous Comm Adapter 7.95 Transmit level -15 Mom nominal, from -6 dbm 2114-3 10211(4 Static 300ná 1C 95 k106852 Synchronous Sena1 Data Maul. 9.95 to -20 dbm. 21141-3 102494 Static 300ns Ion power 1195 MC6860 0.600 bps Dlptat MODEM 12.95 Receive Frequency Tolerance Frequency relerenee automatically a2Iusls to SPECIALTIES 5101 25614 Static 7 95 CONTINENTAL for =0= MC6862 2460 bps Modulator 14 95 allow operation between 18110 Ha and 2400 HL 528062107 409601 Dynamic 4.95 58268300 Ouad 3 -State Bus Trans Digital Data Interlace EIA R5 -232C Or 20 mA Current toot/ (receiver d (MC8726) 2.25 7489 1684 Static 8.75 MICROPROCESSOR oplmscldted and non.00100 LOGIC PROBE KIT CHOPS -MISCELLANEOUS 745200 25681 Stall Tnstate <.95 Power Requirements 120 VAC, smote p 10 Walls. -28017800) CPU 513.95 - 2 93421 25601 Static 95 Rgsical All components mount on a single 5" by 9- 180617801) CPU 15.95 UPD411 48 Dynamic 16 pin < 95 pnntee drool board MI components included. CDP1802 CPU 19.95 18540271 Requires a YOM, Audio Oscillator, Frequency Coupler and or OscillOSCOpe 10 align. 2650 MPU UP0416 168 Dynamic 16 on 25015 995 6502 CPU II 95 (0641161 SPECIFICATIONS 8035 8.011 MPU w/clods. RAM. 1 O ones 19.95 75154044. 48 Static 14,95 TRS-80 P6085 CPU 19.95 4561 Input Impedance: 300,000 Ohms. TM5990%JL hardware. 16.5, MPU w multiply 0054045 102494 Static 14,95 16K Conversion Kit Thresholds: "Lo" 30%Vcc - "Hi" 70%Vcc 6 divide 49.95 2117 16.38457 Dynamo 35019 9.95 SHIFT REGISTERS mouse marked) 4K TRS-80 System to 16K. Maximum Speed: 300 nsec., 1.5MHz Expand your MM500H Dual 25 Bit Dynamic 5.50 005262 2801 Dynamic 181.00 Kit comes complete with: Input Protection: ±50VDC continuous 117VAC MM503H Dual 50 ea Dynamic .50 PROM'S 8 each UPD416-1 116K Dynamic Rams 1 250NS for 15 sec. 905048 Dual 16 &t Static .50 Documentation for conversion 1405066 Dual 100 Bit Static .50 17029 2048 FAROS S5 95 Power: 30mA @5V -40mA @ 15V - 25V max. 905108 Dual 64 &1 Accumutlor .50 2716161E1 168' EPROM 59 95 reverse voltage protected; 36" cable with color IAM5016H 500/512 88 Dynamic 89 TMS2516 161' EPROM 39.95 TRS-16K $75.00 2504T 1024 Dynamic 395 (27161 'Require: smote 4.56 power supply coded clips included. 2518 See 32 Bd Static 4.95 TMS2532 4698 EPROM 89.95 Operating Temp.: 0-50°C. 2522 Dual 132 &I Static 2.95 2708 95 EPROM 10.95 .99 2716 T.I 168" EPROM 29.95 x 1.0W x 0.7D in, 2524 512 Static Dimensions: 5.8L 2525 1024 Oynami< 2.95 "Requires 3 cottages, -5V, 5V, +12V (147 x 25 x 18mn1) 2527 Dual 256 94 51a80 2.95 5203 20,8 FAM05 14.95 Weight: 30 oz. (85 gin) 2528 Dual 250 Static 4.00 6301.1176111 1024 instate Bipolar 3A9 2529 Dual 240 Bit Static 1.00 6330117602( 256 Open C Bipolar 2 95 LPK-1 521.95/Kit 2532 Quad 80 Sit Static 2.95 82523 3208 Open Collector 3 95 3311 Filo 6.95 825115 9096 &polar 19 95 7410670 41(4 RegOter File (TnSlate) 2 49 825123 3288 Instate 3 95 30 AVG wire .025 square posts /////// 74186 512 111 Open Collector 9 95 Daisy chain or Built-in cut off DART'S 74188 256 TR Open Collector 3.95 point-to-point Includes 50 ft. wire ,, 1024 2 95 Proto Clips A.1.5.1013 305 MUD 5.95 745287 Static No stripping or slitting required - /gil, just wrap 14 -PIN CLIP PC -14 .... S 4.50 JE600 HEXADECIMAL DIGITAL W103 16 -PIN CLIP PC -16 S 4.75 .... ENCODER KIT THERMOMETER KIT Pan No. Color Price 24 -PIN CLIP PC -24 . S10.00 JW-1,8 Blue S14.95 40 -PIN CLIP PC -40 S16.00 FEATURES: 'WW1 .... JW-1-W White 14.95 Fan 8 bit IMO.," Output let m,ero' processor use JW-1,Y Yellow 14.95 3 User Define keys Will one being be JW-1-R Red 14.95 stable at:arg an Proto Boards for an 19 Denounce taco provi0ea keys P13-6 $17.95 1t- JUST UJRAP' Replacement Wire LEO readout nnry entres J4i.. PB-100 19.95 Easy nsertanrg with standard 16 pin X Pan No. Color Prke PB-101 22.95 IC connector J R-JW-B Blue 50 ft. ron S2.98 PB-102 26.95 Only .5VDC remind tot operation, 11 R-JW-W White 5011. ron 2.98 y t / PB-103 44.95 FULL 8 BIT LATCHED OUTPUT -19 KEYBOARD Duels so -witching control for in. R-JW-Y 50 /t. S PB-104 55.95 The 28600 Encoder xeye,ard provides tars separate heradecimal door/outdoor or duel itoring Yellow roll 2.98 Omits produced horn sequential key entt,n to allow pied pre9. Continuous LED .8" ht.dIsplay R-JW-R Red 50 ft. roil 2.98 _ PB-203 99.95 Range: -40°. to 1990E / .40°C to 100°C ow.,^ PB-203A 155.00 ramming 5,667 microprocessor or 8 bit memory circuds Three Accuracy: ±1t nominal PB-203A-Kit .. 131.00 431 add,boral keys are provided for user ode'aiens with one having Set for Fahrenheit or Celsius reading a listable output avalbble The outputs are alcnea and monitor ea Unwrap Tool $3.49 Sim. walnut case - AC wall adaptor Incl. JUST WRAP' with LEO 'cutouts Also included 6s a key entry space Slze: 3.1/4-H x 6.5/8"W x 1.3/8"D JE600 $59.95 6 Clock Kit e. Jumbo -Digit 1 ; 7 a Hexadecimal Keypad only 514.95 JE300 $39..95 Four .630"ht. and two .300"ht. oic common anode displays Uses MMS314 clock chip Vacuum Vise Switches for hours, minutes and hold functions 62 -Key ASCII Encoded Keyboard Kit Vacuum.based light -duty Hours easily viewable l0 30 feet FEATURES: vise for small components Simulated walnut case 60 Keys generate the full 128 char- and assemblies. ABS con. ISS VAC operation acters, upper and lower case ASCII 5 uctlon. 1'h" laws. 1:4'' 12 24 hour 2r+ .« permanently or operation .yaj set travel.Can be Installed, Includes all components, case and wall transformer inn iellrEL"sYI[rd_. Fully buffered + 514e, 684 a eve x 11. fa) J6PrrlatrP Q]. 2 user.deline keys provided foe VV -1 I0351114. l9l11I9rl'tY -z74 custom applications $3.49 c k pL It i Caps lock for upper case only JE747 $29.95 alpha characters ADJUSTABLE WRENCH Utilizes a 2376 140 pin) encoder cart,. - Borlght s30Óht. comm. read only memory chip 11 rl.sr-ter-tí s^_ The JE610 62 -Key ASCII Encoded Keyboard 7a) clock chip Outputs directly compatible with Uses MM5314 Kit ca n be interfaced into most any com- TTL/DTL or MOS logic arrays witches for urs, minutes i . 1 1:0d O0 S Two Sizes: 6" and 10" an hold modes puter system, The JE610 Kit comes com- Easy interfacing with a 16.pin dip or 18 -pin edge connector Professional Quality Hrs. easily viewable to 20 1t. plete with an industrial grade keyboard Chrome Vanadium Steel _ Simulated walnut case switch assembly 162 keys), IC's, sockets, Y 115 VAC operation connector, electronic components and 6ee- AW-6. , $4.95 10ee- AW-10.. $6.95 12 or 24 hr. oporatlon double -sided printed wiring board. The JE61O $79.95 walll t as n 6 119, keyboard assembly requires +5V @ 150mA J E 701 transformeri @ for 62 -Key Keyboard only..S34.95 JOYSTICK S i e: 6'/a" *3-1/001%" and -12V 10mA operation. VIDEO CONTROLLER 6 -Digit Clock Kit $19.95 HICKOK 1X303 Portable LCD Digital Multimeter e, MY. hwh,3,0qLnullGrtaDnn, 0.x10w°u.r non .Don ,,rna,Nnu,wr Regulated Power Supply ,Ro. ..°...° ae. - as i,-,.na ro.st Uses LM309K. Heat sink tul provided. PC board con- "- . o° ::1F. ., e ,.s.i. n... -x4 k : struction. Provides a solid" oc - sra .aa,..la,. Se .,w,.,.w- «,..i -.n.. -..c-.,. 1 amp @ 5 volts. Can supply up - rzur 4,.. to e5V, e9V and á-12V with , JE205 Adapter. Includes compo- _ LX303 Digital Multimeter $74.95 nents, hardware and instructions. Size: 3%" x 5" x 2"H RC] 115V AC ADAPTER 7.50u,c, CC:17 PADDED CARRYING CASE 7.50 VP0 X10 DC PROBE ADAPTER 'Up to 1010 14.95 JE200 $14.95 VP 40 40kV DC PROBE...... 35.00 CS.I 10 Amp DC Current Shunt . 14.95

510.00 Min. Order - U.S. Funds Only Spec Sheets - 25d 1.," ADAPTER BOARD 6% Sales Tax 1980 Catalog Available -Send 41d stamp ,9"41.ti,, Calif. Residents Add . -Adapts to JE200- Postage -Add 5% plus Sl insurance (if desired) IDEAL FOR ALL VIDEO GAMES OR REMOTE CON 11 ±5V, ±9V and ±12V PHONE TROL PROJECTS 1-1/2"H x 2-3/825 x 4-5/16"L ORDERS SMALL CASE SIZE: DC/DC converter with +5V input. Toriodal hi MINIATURE POTENTIOMETERS-40K OHM EACH Emeco WELCOME 2 speed switching XMFR. Short circuit protection. SPOT PUSH BUTTON CONTROL PC Piggy 111 ELECTRONICS (415) 592-8097 board construction. -back to JE 200 5 -WIRE CONNECTION CABLE - 5 FEET LONG board. Size: 3Ye" x 2" x 9/16"H MAIL ORDER ELECTRONICS - WORLDWIDE RUGGED PLASTIC CASE 1355 SHOREWAY ROAD, BELMONT, CA 94002 JE205 $12.95 5.80 PRICES SUBJECT TO CHANGE JVC-40 $4.95 each)

AmericanRadioHistory.Com 'MURAPH0NE'r DIGITAL MULTIMETERS '`Portable VOM 100 MHz 8 -Digit Counter CSC "6" x 9" 3 -Way Speaker Cordless Model MAX100Re Sinclair PDM35 Hickok LX303 Multitester('J 20 Hz to 100 MHz r 20 oz. ceramic magnet 1 . S150.00 Model Reg. $69.95 $6950 Telephone Model LED display BP2000-69TR VM520 1995 Fully automatiec $4995 System 2750 $1495 ea. Reg. 589.95 20K11VDC10KDVAC $7495 CODE -A -PHONE i HICKOK =S= Logic Monitor'Telephone \xi. Automatically Answering Digital CB In Line Vdisplays static and dynamic logic Model 1500 $24995 8 pc. Tool (value Tester Model LM -1 Works with DTL, HTL, Call Control Set Reg 5349 95 514.95) with 5200.00 31/2 1111. TTL, and CMOS 16 -Digit Beckman GTE Flip-Phoned purchase from this ad. LED display Model 1400 $1 Portable TECH310 $3795 $16995 9995 Reg. 1165 $130. $399.00 j+%PN£CISION Portable WAHLL Miniature High Fidelity Model 2800 ' Model 388 3 -Way Stereo Speakers Digital Ca í acitance Cordless Reg. 5149.95 Portable Oscilloscopes,r Weller Xcelité Meter 1450 Soldering 56950 1116102 15 MHz Function Attache Iron Model 820 7PRi fw '3 l Dual Trace Generator Style Measures IRr capacitance $2995 Triggered Tool Case Model 7800 !Model 99 from 0.1pF to 1 Farad Resolves to Model TC100 ST HE -9 Miniscope e=. . 0.1pF 10 ranges for accuracy and L/1 Model 2001 Thera. L Model sue resolution 4 digit easy -to -read LED a -S 1 Model MS -215 Reg. 5185.95 SI $27995 :2995' '369955475900 display 0.5% accuracy Circuit Tester In -Dash Car Stereos $15795 Service 8 Track Tape Player with 15 MHz Triggered Miniscope Sine-, square-. Master CS= 31/2 -Digit 0.1% Digital AM'FM/MPX Radio Model MS -15 Reg S319,00$269955 triangle- and Capacitance Meter Model 3001 Model C-777 .7 separate TTL Tool Kit t it ranges from 1999 square wave Model 99-SM . 9 pF to 199.9µF 0.1% of reading accuracy $5250 v (A 30 MHz Dual Trace output Reg. . Reg. $1 ) $4750 5190.00 --' Frequency range: 569.95 _ 70 Triggered Miniscope 1Hz-100KHz DIGITAL MULTIMETER Cassette Tape Player Model MS -230 Reg 5559 00 $47995 461 with AM/FM MPX Radio Proto Complete with nickel - =M= Proto Board with gA Model cadmium batteries. AC Preassembled CAS -888 Built-in Power charger/adapter, test Logic Boards leads $5750 Probe Nadel Supplies $14995 !1J Compact circuit powered AL_ tO~. PB-104 Regulated Detects pulses as shod as 50 Fully assembled breadboard Short -proof Remote Control for µsec DTL TTL/HTUCMOS contains tour OT -59S sockets. Reg. 5154.95 BSR Lights 8 Appliances Stereo Power Booster compatibility X-10 $4495 seven 01-598 bus strips and four odel PO -way binding posts $12995 111-2036 25ií l 40W eo $2495 ®®n t ¢@Dn-1 t1`.el FRC Circuit Box .; 30 MHz LEADER Pe standard Stoner Kit One In Stallard Command Red 581 95 C moo Too 121 U,0 moues One 02000ncn 36 resistors 115 it -. If) 57950 t0 10 MO) 18 Dual Trace Magnifier Lamp Pc Ultrasonic Starter ire One II) Otiue Ulnasone Reg 5112 9 o E 4'= r capacitors (100 to with Delay P Csonic One Hand Held pl Precision ground and polishhed 11) Remote and T., s9995 121 Lmp Mod Oee 111 UnT 0.22 Line 5. Appance 0 n magnification lens $4995 855 Conklin St. Farmingdale, N.Y. 11735 Reg.S49.95 95 Lane dnies $14.50 standard Command Console 536.00 Master Charge $42 Model MG10A 7 899 550 FOR SHIPPING ANO INSURANCE APPKWIC!corn ! rimes 514.50 wnaso i5 Console s59.95 Ban N Amencard 'Includes test leads viz Model WC 412A to 3 2sa.00 3 3.50 Model L80-520 w,R eicame 7adv«s 014.50 Hand "8816."'"15, VISA COD 5251.0010 500.00 5.00 Money Order 501.00 m 750.00 7.50 Chess Model WTCPN PRECIS/ON 751.0010 1000.00 10.00 WellerControlled 30 MHz N.Y. reeeents add Reg. 077.50 Stale COP1000.00 12.50 sea Challenger 7 Output Soldering Portable Frequency Dpropeale sales S talla Reg 5110.00 Model $4995 Station Counter Reg. 513Q00 _. TOLL 7995 BBC FREE (800)645-9518 in N.Y. State call (516) 752-0050

- SOUND EFFECTS GENERATOR BASIC KIT camputiqué cr' camputique . ty -camputique Now CHANEY ELECTRONICS HAKES IT POSSIBLE TO BUILD YOuR Ow, SOU Eet Etts GENERATOR WITHOUT SPENDING Aral LANE. WE SUPPLYPPLY YOU a THE 1176477 SOUND CH PLUS AN ETCHED T ANC DRILLED S (EPDXY PC OARD HIT» SCHE TIC AND LAYOUT INSTRUCTIONS. TEXAS INSTRUMENTS INTRODUCING THI6 BOARD !MBES IT SIHPLE TO BUILD A GENERATOR CAPABLE OF E TT PHAE SOUNDS, SIRENS, [hP] HE DOES NOT REQUIRE DPDI D SWITCHES oa OTHER EXPENSIVE/UNUSUAL electronic colculotors THE HP COMPONENTS.1101roAoeD RESISTORS, CAP- HP867 $299.95 -85! ACITORS, POTS, SPEAKER, 2N2222 TRANSISTOR AND 9V TI35 NEW S24.95 TI.5100 $39.95 BATTERY. BASIC IT 0.0.110 NG HP92 399.95 sea06i¡Ns ao - 11.50 33 50 Programmer 48.95 B HP97 584.95 nRvcno"s orar $5.95 TI.55 3495 MBA 59.95 HP -33C NEW .109.95 ) 1RA141610R FOR Aeon 262222 =ACM TI.58C NEW 109 95 Business Analyst I 21.95 -Tor .... -34C NEW IF HAVE ALREADY PURCHASEDP THE 1176477 HIP YOU WAY Bur HP .124.95 6,p 54,Ó0 TI 59 209.95 Business Analyst II 39.95 THE PC eoARo ASO INSTRUCTIONS ONLY. C23885 HP -38C NEW .124.95 TI.58/59 Libraries ..28.95 Business Card NEW 39.95 \\ StrobeTube &Trigger O° LED HP -31E 41.95 TI.30SP 17.95 Language Translator NEW 279.95 j Flasher HP.32E 54.95 - PC -100C 146.95 Digital Thermostat NEW 104.95 r«.a.R uaQ Kit HP -33E 73.95 The HP -85 'is a powerful 021051 71.1750 19.95 Speak & Spell . 65.00 HP.37E BASIC language computer Modules 59.95 51.75 .o 11 5015 64.95 ea. 14.95 complete with keyboard ),,,.i%::05- Q HP -38E 94.95 715040 94.95 Chrono Alarm 806.31 39.95 CRT display, printer, and a, 52.49 HP -41C NEW CALL 2.- tape drive - all in one com- World Time Alarm.Chrono 8073 .. 89.95 . 6VDC Xenon U t Digital ^1 HP -85 . NEW 3250.00 pact unit. Flasher 4 I Counting Y Kit ( O° Module TI HOME COMPUTER 99/4 ... $1150.00 400 $599.95 .'1till 800 ...... 999,95 0-000 JIB (STARTER SYSTEM) X(B1101101 many others. All at GREAT PRICES! 1.85. Each Module 14.95 12 sets for 81.00 sa EI. roHt WE BEAT WILL OR MEET ANY COMPETITOR'S PRICE ON MOST ITEMS IF HE HAS MERCHANDISE ON HAND. R0170 Mini Reed All units shipped in original factory cartons with accessories according to manufacturer's specification. CALL Rectifier IHIANRE Switch TOLL FREE (8001 8540523 CA) or DJUSTABLI (outside 1714) 549-7373 (within CA). Visa and MasrerCharge; money order; Pers. Ck. Wks. to c"'°' 5 for 51.00 CAPACITOR (3 clear); COD accepted. Min. 94.95 for shipping in USA. We ship AIR on request. CA residents add 6% sales tax. 100 for 515.00 5 for 51.00 c240e350Q . All merchandise subject to availability. Prices good only with this ad for limited time only- s.-^ Send orders to Dept. POPE L -M Tube Specials Ple070~, ' Horse- - WRITE OR CALL FOR FREE CATALOG ss CRP/ ( shoe ( Tube 350 ref 330V 100 a Im 720 511 360V 150 I 53.95 cry computique Minimum order 55.00 Please Include 57.00 for postage 3211 SOUTH HARBOR BOULEVARD, SANTA ANA, CA 92704 6 Stores in California -f{_CHANEV Visa, MC and COO accepted electronics inc. Phone orders are welcome CALL TOLL FREE (800)854-0523 (outside CA) (714) 549-7373 (within CA). .14.0.80X 27038, DENVER, CO. 80227 1303) 781.5750 Send for our free giant catalog of unique items !!! PROFESSIONAL DISCOUNTS CIRCLE NO.9 ON FREE INFORMATION CARD CIRCLE NO. 12 ON FREE INFORMATION CARD

AmericanRadioHistory.Com Zilog

28001 $195.00 16 Bit CPU with segmented address space to 8 Megabytes. Z8002 5150.00 16 Bil CPU with non segmented address space to 64K bytes. Z8000DB 51500.00 A complete single board Z8000 microcomputer system. Contains the Z8002 microprocessor, 16K words of dynamic RAM, 2K word monitor PROM. dual serial interfaces, lour counter/timers and 32 programmable parallel I/O lines. All Products Stocked in Depth Largest Zilog Inventory

Z80 -CPU 2.5 MHz $10.50 Z80 -DMA 2.5 MHz 526.85 Z804 -CPU 4.0 MHz 12.50 Z80A-DMA 4.0 MHz 33.60 ZOO-P10 2.5 MHz 8.00 Z80-SIO/O 2.5 MHz 36.00 ZBOA-PIO 4.0 MHz 1 9.60 Z804-SIO/O 4.0 MHz 44.10 Z80-CTC 2.5 MHz 8.00 Z80-SI0/1 2.5 MHz 36.00 Z804-CTC 4.0 MHz 9.60 Z804-510/1 4.0 MHz 44,10 Z80-SIO/2 2 5 MHz 36.00 44.10 METAL POWER TRANSISTORS Z804-SIO/2 4.0 MHz MICROPROCESSOR Homotaxial - Best Quality CHIP SETS 2N3054 .65 60V NPN TO -66 MOS MEMORIES RAM's 2N3055 .69 70V NPN TO -3 Part 5o MOS Static Price 2102LFPC 1.19 Pan No. Price Part No. Price Part No Price 2N3442 1.50 160V NPN TO -3 16 (16 x 1) Low Power 350ns 16 PIN TO 2N3771 1.95 50V NPN -3 2102LHPC 1.29 $5.95 6800 56.95 6502 $9.95 8080A 2N3772 1.95 100V NPN TO -3 16 (1 6 x 11 Low Power High Performance 250ns 16 PIN 8085 12.95 6802 11.95 6504 9.95 2N3773 2.50 160V NPN TO -3 2102.1 PC 0.94 6505 9.95 SCR 16 (16 x 1) 450ns 16 PIN Universal 0.89 8212 2.95 6810 3.95 C106D .34 400V 5.0 AMP TO -220 2102-2PC 1K (16 x 1) 650ns 16 PIN 8214 3.95 6820 3.95 6520 6.95 P2111-25 2.25 16 (256 x 4) 250ns 18 PIN 8216 2.95 6821 3.95 6522 9.95 EPROM'S P2112-35 2.25 6850 4.25 6532 13.95 1K (256 x 4) 350ns 18 PIN 8224 3.45 C2708 $ 6.95 2114L 5.95 8226 2.95 6852 3.95 6551 13.95 1K x 8 4áo ns Low Power 46 (1024 x 41 300 ns 8228 4.98 1`' TMS2716 S24.95 MOS Dynamic RAM's 16K (2K x 8) 450 ns 8238 4.98 TMS4O60.30 2.95 11.1, 13 power supplies) T.I Version 41( (aX x 1) 300ns 22 PIN 8251 6.95 C2716/TMS2516 523.95 TMS4060.20 3.95 8253 10.95 16K(2Kx8) 450ns 46 (46 x 1) 200ns 22 PIN I Single 5V supply Intel version) UART's 8255 6.95 Speciall - A05-10134 $4.95 10.95 8257 1.:::: 0 to 406 BAUD 40 PIN 8259 12.95 of the month --)Iii "1""g AY3-1015 5.50 16K MOS DYNAMIC RAM'S (16 PIN) 0 to 306 BAUD 40 PIN Single 5v suooiy 1K RAM MU 416-5 (300ns) CERAMIC 55.95 CMOS mu IZ;;;;, 4.95 S7.95 5101 \ 416-3 (200ns) CERAMIC 16 (256 x 4) 450ns 22 PIN Low Power LINEAR I.C.'s mizi ma nu IV-. 4K CMOS RAM LM3015-8 .34 LM739CN-14 1.29 P4315.45L 4K (4K x 1) 450ns 18 PIN 14.95 LM307N -8 .29 LM74 I CN-8 .49 -ti` P5047-55/UPD455 LM308CH .95 LM747CN-14 .59 1980 IC MASTER 4K (1024 x 4) 550ns 20 PIN 110MW 14.95 LM311 N-8 .59 LM748CN-8 .39 JUST RELEASED over 2700 PAGES P6504 LM324N .59 TBA810DA$ 1.29 4K (46 x 1) 550ns 18 PIN 110MW 14.95 Master guide to the Iatesl 1 LM339N .99 LM1458N48 .49 Complete integraled circuit data selector. P6514 and consumer circuits. 45,000 1M3485-14 .55 LM14885-14 .69 I C.'s including microprocessors 46 (16 x 4) 450ns 18 PIN 110MW 16.95 device types listed 5.000 new device types added. Complete new LM358N-8 .99 LM 1489N-14 .69 SecliOn on MPU boards 3 Sysla ms. SHIFT REGISTERS LM5555 .59 LM3403N-14 .99 4.95 LM5565-14 .49 LM3900N .59 Free 05:01 3341PC FIFO 700 KHz .99 Quarterly LM723CN-14 .49 LM4136N-14 5.50 Special S59.95 3341APC FIFO 1 MHz LM725CN-8 1.25 /".:Updates 3342PC 64 Bit Shill Register 4.95 :':.. 3347PC 80 Bit Shift Register 4.95 SOUND & MUSIC DUAL -IN-LINE - LOW PROFILE - I.C. SOCKETS ECL RAM # 10410ADC/HM2106 Special 1.95 PRICE CONTACTS PRICE 16 PIN GENERATOR I.C. CONTACTS 256 x 1 Bit Fully Decoded 15ns .07 22 PIN 21 Creates almost any type of sound. from music to 8 PIN PIN ,it 24 PIN 23 gunshots and explosions. High level op amp output 14 16 PIN .13 28 PIN .27 L.E.D. LAMPS 28 pin DIP. Operates from one 9V battery. 18 PiN .17 40 PIN .39 1%1 mm Red .09 With data 20 PIN .19 LED209 3 LED211 7-1 3 mm Green .19 FOR THE HIGHEST OUALITY. AN UNBEATABLE "Lowest Price Offered LOWEST PRICES ANYWHERE LED21 2 T.1 3 mm Yellow .14 Anywhere" COMBINATION. PERFORMANCE CHARACTERISTICS CONFORM TO THE REQUIREMENTS OF LED220 T -Y. 5 mm Red .11 S 2.49 SN76477N (.600" centers) MIL-S.83734A LED222 T-1'/. 5 mm Green .24 .16 SN76477NF (.400 centers) $2.29 OPERATING TEMPERATURE: -65 C TO -125 C. SOCKET SALE LED224 T-11'. 5 mm Yellow DISPLAYS New small package" FLAMEABILITY RATING UL345-0 J F5D357 .375- Common Cathode 1.09 FND367 .360 Common Cathode 1.29 PLASTIC POWER (high brightness) SMALL SIGNAL TRANSISTORS FND500 .500 Common Cathode 1.09 METAL CAN PLASTIC TRANSISTORS FND507 .500 Common Anode 1.09 FND560 .500 Common Cathode 1.29 .29 252484 .21 253391A .10 254402 .09 2N697 TIP30 .39 PNP 1 AMP 1000 (high brightness) .10 254403 .09 1.29 25918 .21 2529044 .29 253415 TIP31 .42 NPN 3 AMP 1000 FN0567 .500 Common Anode (high brightness) 25930 .21 2529056 .29 253704 .10 254410 .13 .43 PNP 3AMP 100V TIP32 01704 .300 Common Cathode 1.29 2N5064 .24 2N1304 .49 252906A .21 2N3819 .29 TIP41 .59 NPN 6 AMP 100V DL707 300- Common Anode 1.29 2N1307 .59 252907A .21 2N3904 .09 2N5401 .14 TIP42 .64 PNP 6 AMP 1000 DL747 .630- Common Anode 2.29 251309 .79 2N3019 .25 253905 .09 2N5550 .14 TIP115 .59 PNP 2 AMP 60V 60V ISOLATORS .34 2N3053 .29 254058 .14 255770 .12 TIP120 .64 NPN 5 AMP 251613 ILD74 Dual Opto Isolator 1500V 1.29 TIP122 .74 NPN 5 AMP 100V 25/893 .34 2N3250 .15 254123 .09 255772 .12 IL074 Quad Opto isolator 1500V 3.95 TIP125 .74 PNP 5 AMP 60V 1.29 252219A .29 253251A .25 2N4124 .09 2N6027 .24 MCT6 Dual Opto Isolator 1500V 1000 1500V .59 .09 256028 .24 TIP127 .85 PNP 5AMP TILIII Opio Coupler 2N2222A .21 2N3962 .25 2N4125 .59 TIP2955 .83 PNP 15 AMP 60V 4526 OpIo Isolator 2500V 2N2270 .34 254093 .55 254126 .09 4N28 Opto Isolator 500V .59 TIP3055 .70 NPN 15 AMP 60V 4N29 Opto Isolator 2500V .69 2523694 .21 255109 1.45 254400 .09 FT3055 .59 NPN 10 AMP 60V 4532 Opto Isolator 2500V 2N2483 .15 2N4401 .09

P.O. BOX 1035 FRAMINGHAM, MASSACHUSETTS 01701 Over-the-counter sales. MINIMUM ORDER 510.00 . ADD 52.00 TÓ -- 12 Mercer Rd., Natick. Mass 01760, COVER POSTAGE & HANDLING Behind Zayres on Rte. 9 Foreign customers please remitipayment on - 879.0077 Active.4E1mtrOniç Telephone Orders 8 Enquiries (617.) an International bank draft or international postal money order in American dollars. - I 'CANADA .I 4800 ST. BAXTER CENTRE 3070 KINGS W AY 1 5651 FERRIER ST. DUFFERIN master 1 B.C. charge MONTREAL, QUEBEC -DOWNSVIEW. ONTARIO - 1050 BAXTER ROAD ' VANCOUVER. H4P 265, M3H 5S9 OTTAWA. ONTARIO V5R áJ7 li Sales Corp. Tel.: (604) 438-3321 - Tel.: (514) 731-7441 Tel.: (416) 661-5115 K2C 3P2 I Tel.: (613) 820-9471 rl " It

MAY 1980 CIRCLE NO.2 ON FREE INFORMATION CARD 109

AmericanRadioHistory.Com P.O. Box 4430C, Santa Clara, CA 95054 Will calls: 2322 Walsh Ave. NEW PRODUCTS! Same day shipment. First line parts only. (408) 988-1640 Factory tested. Guaranteed money back. Super Color S-100 Video Kit S99.95 Elf II Adapter Kit S24.50 Quality IC's and other components at fac- Expandable to 256 o 192 high resolution color Plugs Into Elf II providing Super Elf 44 and 50 pin tory prices. graphics. 6847 with all display modes computer bus plus S-100 bus expansion (With Super Ex- controlled. Memory mapped. 1K RAM expanda- pansion). High and low address displays, state INTEGRATED CIRCUITS ble to 6K. S-100 bus 1802, 8080, 8085, Z80 etc. and mode LED's optional $18.00. 7100111 1413236-5 5.95 C04021 1.25 ELECTRONICS Gremlin Color Video Kit $59.95 1802 16K Dynamic RAM Kit S149.00 741106 17 313201012 1.50 c04022 1.10 1 74024 I 1.613208.15 54 C04023 28 4 95 RESISTORS 11 wan 53. 1 75 210481 32 x 16 alpha/numerics and graphics; up to 8 1802/S-100 71045 19B 14132015 6 004024 expandable to 32K, Hidden refresh 3 75 10 03 1000 type 012 1.60 28 210706 per 0pe per , 74094 13 332076 001025 Plugs 4 MHz 2111.1 3 75 25 per type 025 350 pope paco colors with 6847 chip; 1K RAM at E000. w/clocks up to wino wait states Addl. 16K 74106 .18 114320112 1.5'1 004026 2.00 N82026 3,25 lOD per type 015 5 per type 6 75 7414N 10 313201.15 1 63 C0027 66 9825729 3 75 into Super Elf 44 pin bus. Not expandable to high RAM $79.00. 11141 30048 1 áá W wan 594 per Iyoe .05 7420N 18 143244 1 15 004028 .85 5825131 3 75 4116 700ns 9 50 74224 1617396 1.55. 004029 1.02 8825136 8 75 KEYBOARDS resolution Graphics. r 814116 200ns 64 00 71306 A L43409.5 8.31 C04030 45 5825137 8 75 56 MI 577 1,02 25138 6 30 + 74424 I143406.8 135 004035 068577 290 9145261 40 44ssembleaypoara 50 74454 1613409.12 1,35 C01040 1.02 23 2 90 53 key ASCII keyboard 44 60 00 Quest Super Basic programs. Cassette version in stock now. RUM .69 61115280 300 74011 143405.75 1.35 CD4042 85 822716 Intel 240 00 Fpby assemmm 70 00 6 0 46,5320 9.95 versions coming soon with exchange privilege 74485 183406.24 1.35 85 Enclosure 14 95 Quest, the leader in inexpensive 1802 systems 69 14115330 591 1434013 1 25. D Ó44 BS CONNECTORS 97,111 for version. 71505 15 P04110.3 400 Enclosure 2995 allowing some credit cassette 1 announces another first. Quest is the first com- 74144 35 143407.8 1 25 C04046 67 30 pin edge 2 50 7041111-4 5 CO LE09 71754 49 313401-12 1.25 004019 45 pin edge 1 75 P5101L 8 95 Red 1018 15 pany worldwide to ship a full size Basic for 1802 Super Basic on Cassette $40.00 74554 BB L14340115 1.25 004050 42004 9.95 Green yeuow 1018 20 74890 1.85 31740118 1 25 001051 1 179 100 ppen edge WW 5.25 systems. A complete function Super Basic by 82525 2 90 Jumbo Red 20 Tom Pittman's 1802 Tiny Basic Source listing 7490N 143401.24 115 C0460 1 42 911024 1 50 G,een, Orange. Bolo* Jumbo 25 71924 433 33434 450 C04066 77 IC SOCKETS Ron Cenker including floating point capability 900165.5 6 95 Mounting now available. Find out how Tom Pittman wrote 74935 13 14350 /.50 004068 10 Solder no low Pm11Ie Cllpli81110 Clips 1135 25 14457100 4 50 end, ambo, ydmw clear) with scientific notation (number range z.17E0), 7495N 14370 115 004069 40 PIN 1UP PIN 1UP Ispeols green, Tiny Basic and how to get the most out of It. G1AY38500-1 9 95 741006 90 11377 3 00 C04010 50 32 bit integer s2 billion; Multi dim arrays; String 28 MC4661514 9 95 14 CONTINENTAL SPECIALTIES In :lock Never offered before, S19.00 741075 1.14379 500 004071 11 2 3355 9368 3 50 Complete ene of 5,eadbwnl7esr,gulp I/O, Save 74121N 31 1.438011 100 004072 .28 I6 .161 28 arrays; String manipulation; Cassette 4100 10 00 488.100 B 41011 1re9. Clr. 5128.95 741235 59 1.61381 160 004073 28 18 2 36 581 S-100 4 -Slot Expansion S 9.95 416 1600 1 28 and load, Basic, Data and machine language pro- 741254 45 11382 60 C04075 20 29 40 57 OK WIRE WRAP TOOLS In sloc4 1414511 65 LM103H 40 CD4076 145 218.8374 pen en. 20 Pedal. Munlmeler SIB.00 grams; and over 75 Statements, Functions and Super Monitor VI.1 Source Listing 515.00 11170911 28 004078 .40 CLOCKS 7416011 95 445311 5.50 141239 N 50 00431 28 WIRE WRAP LEVEL 3 SPECIAL PRODUCTS Operators. 741515 6 Coming Soon: Assembler, Editor, Disassem- 1.4733 67 M05312 3.90 P19 PIN N145865 1,0/1, 741546 1 OD9 004082 28 Stopesalcn 6615314 3 90 741575 1.474101 35 004116 1+ 32 N 66 wan 10 a9 spec 9 00 Easily adaptable on most 1802 systems. Re- bier, DA/AD, Super Sound/Music, EPROM 69 445369 741615 87 LM7416 32 CO 490 5 50 210 16 33 26 100 PC 00138 7 50 MM5841 1145 quires 12K RAM minimum for Basic and user programmer, Stringy Floppy Disc System. 741626 LM11)HM 75 004507 1 00 18 57 40 1 23 5w901e0 Mom 7451181104 27 a 611.15969 795 741635 8181 11474166 35 C04508 25 3 804 Ode 25 CT7001 5 B0 741744 96 1413035 1 75 0D4510 102 CRYSTALS Encoder 400165.5 6 95 C77010 8 95 741755 90 LMI304 1 10 004511 91 I MI5 a 50 Pa0,147l*s 1004 Logic 017015 8 95 741906 15 141305 1.21 C04515 2 52 2 MHz 4 50 811 5224.00

1 10 9M551544N 390 741926 81 141307 200 c04516 4 MHz 4 25 MoAnalyzerdell10 hedger M45315411 4 90 741936 BS 181310 275 001518 1 02 5 MHz 4 25 brander 101 5229 00 11 7205 16 50 742214 1 00 141458 004520 1.02 10 MHz 425 Model 150 Bus 7207 7 50 742996 65 141600 1.75 C01527 I 51 18 183 3 90 Grabber Kr 5369 00 7206 15 95 743656 65 0141811 7.50 C04528 79 206X5 390 SMxt4113 0Í0/1 4 95 1111889 300 C04553 3 50 7209 32 MHz 390 M4 559.95 1.75 2 25 0500263i 3 75 743674 66 142111 C04566 32768 Hz 400 CI5ck 11ter 523.95 0500560N 3 75 182902 1.50 C04583 4.50 8432 655 1 50 2.5 MHz Free.. M453104 2 50 741500 70. 1839004 .60 c0585 1 10 3 5795 MHz 120 Counter 611 637.50 1 75 7415006 143905 C040192 3 00 2 0100 MHz 1 95 30 Mot Frequency 35 MICROPROCESSOR 70.50211 35 1.1439094 89 74000 28 2 097152 490 4.50 Counter 611 547.15 7430411 35 61C14584 .50 74004 40 2 4576 MHz a 50 6504 16.50 TRANSFORMERS 7425055 35 NE5404 3,75 74010 28 3 2768 MHz a 50 6522 13 60 6V 300 ma 3 25 141508N .35 NE5505 1.00 74[14 2 10 5 0688 MHz a 50 6800 17 50 12 vole 300 ma transformer 1 25 7415106 35 1113554 .39 7+020740 28 5 185 6141 a 50 6802 18 75 12 69 01 600 ma 375 00E97 74151311 55 5E5564 .85 5 7143 MHz 4 50 sure, Eá 6420 9 95 129 250 ma wall plug 2 95 1415145 110 4E5654 1,00 14045 I 95 6 5536 MHt 4 50 6850 12 95 129 CT 250 ma wall plug 350 7415205 35 4E5664 1.50 74074 75 14 31818 1.110 4 25 80804 5 95 249 C1 700 e,7 3 95 7415125 .35 NE567V 100 74[16 I 40 18432 MHz 450 8085 27 00 OV 12 amp wall mug 4 55 7405286 11 NE5108 5 00 74090 5 22 1144 63, 50 BOB' 7500 12v 6 95 74Ls3o6 35 78145 .60 74093 1.40 4 75 120 500m m a wan plug 1 $ 5 741.53311 75 78108 60 740154 3 00 KEYBOARD ENCODERS R2 2804 19 75 124 1 amp 0171 8149 650 K 7415384 55 786105 85 )40160 I M 0015.2376 512 50 ,.' JLK 8212 2 90 124 3 an 8 50 LI^ 15108 1 75 135 7415145 1 25 740175 495-3600 17 95 f c 8214 800 10rí5 VAC 916 VA wad plug 95 P.,iy , 74LS75N I W 7549104 50 710192 1,65 A95 910010 50 8216 290 tf 1415909 85 7549209 55 740221 2.00 685.9200 16 50 DISPLAY LEOS -...+ray 2 90 7415939 .70 75444CN 89 710905 600 740922 5 50 8497 CA 270 290 740906 82286211 5 75 125 39 7415956 1 10 5 740923 5 50 8093 CC 8 50 RCA Cosmac Super Elf Computer $106.95 741510711 15 A to D CONVERTER 740911 195 1100165.5 4572174 CACA 110 100 8253 tsoD 695 14151126 45 90389 460 740922 5 50 01701 CC 100 1 25 8255 925 Compare features before A 16 HEX 1 you decide to buy any 24 key HEX keyboard includes keys 74491136 35 870001 13 95 740923 5 50 0 00,7189,0 RS232 01707.017075 CA 300 00 8257 19 50 74L51324 .89 870105 22 90 740925 6 95 0057 2.95 017277/28 CACC 500190 other computer. There is no other computer on plus load, reset, run, wait, input, memory pro- 8259 19 50 195 ' 74151366 ,45 875008 13.95 740926 6 95 017/71750 CA/CC 60D 18020P oils 73 95 06255 3 95 a the market today that has all the desirable bene- and Large, on 7415151N 85 10130 995 110922 6.95 Corer 7,50 04150 CC 6001,95 tect, monitor select single step. 20P pees 17 95 14L51556 85 94000IV4 740 A5231 Complete Set 650 150355 CC 357 .70 the 01619 II 50 fits of Super Elf for so little money. The Super board displays provide output and optional high 7451575 85 ICL7103 9.50 INTERFACE 0E95 1,95 1905415507 COCA 500 1 35 007150200 19 95 /4151625 1,15 1017107 14.25 895 65 160503510 COCA .500 90 Elf is a small single board computer that does and low address- There is a 44 pin standard 0071802D 25 00 04157 2.50 7415163N 1.15 80096 65 04155 3 50 190600,807 COCA 800 2 20 0071861 12 95 many big things. It is an excellent computer for connector slot for PC cards and a 50 pin connec- 74151749 100 CMOS 8097 .65 3 091 8980/8 60 741S190N 106 0034001 Farr 50 8098 65 0AR7IFI70 111480a Ph Digit 1E0 4 cmt Bubble 80 8109 1.25 1 15 training and for learning programming with its tor slot for the Quest Super Expansion Board. 14152214 195 A55.1013 5 50 mul*me7er 69.95 005 Fluorescent 8110 4 0610 Fluorescent 1 75 machine language and yet ft is easily expanded all IC's are in- 74052586 67 004001 .1é 8611074 7 50 Stopwatch MI 2695 Power supply and sockets for 05 0 pin 1 74153676 1 35 C04002 .28 8113 l 3341 6 95 Auto Clock Ill 57.99 5 0Í9n 11 0 1peey D0 1.10 8120 5 5 10 1.25 with additional memory, Full Basic, ASCII cluded in the price plus a detailed 127 pg. instruc- C01006 Nola Kit1520 LINEAR 004007 28 8123 3 70 1604 [neap Clack crn,. pñoloce/H 39 511.95 Keyboards, video character generation, etc. tion manual which now Includes over 40 pgs. of 043045 .90 C01008 28 8124 3.SO 11028 395 833640 9 50 ncuaeseremnmgecepl CC 30 1 10 CA3046 t 10 (125 25088 p8r tau 775 80X3670 including a series of lessons to 1.19 2 -PC boards 68 SO- A Before you buy another small computer, see if it software info. 643081 180 0óñóºó 4s 8126 2706 195 88X1640 40 120 8128 2 75 l^0, 71478 S3í4. 40 20 a C43082 1 90 004011 4494670 00 includes the following features: ROM monitor; help get you started and music program and ira 1v 8197 169 40 CA P, sl."1 all 4844710 40 1 95 003089 2.95 004012 28 8327 6 n1 ompo4n na lull m. State and Mode displays; Single step; Optional graphics target game. Many schools and L430140.96 35 C04013 39 8198 I 69 632116 Imes 270 00 MA44740 CC 40 120 stroll+ :Orange di, 1673059 87 C04014 1 00 4846610 CC 56 2 95 a MOO MEMORY r)1 oral Sams 411 t address displays; Power Supply; Audio Amplifier universities are using the Super Ell as course 143015 35 C04015 1 00 Z11Á 5259 48X6710 CA 60 35 48.80- displays. Red 443089 .89 004016 45 RAM 61418 6500 MA56710 CC 60 35 and Speaker; Fully socketed for all IC's; Real cost of study. OEM's use it for training and my 521,95 Case 511.75 R&D. 141309K 1.50 004077 1 05 2101-1 395 of in warranty repairs; Full documentation. 171373314 90 21021 95 87506 70 00 811169 loto. Mr 0 1 95 Remember, other computers only other Super Elf 48100322E0 8.95 LM31 TTde 3.75 0ó4óiº 45 2102811 125 67552 6500 Ileac 790M5, 58900 51514500240011 MÁ10426 6.95 The Super Elf includes a ROM monitor for pro- features at additional cost or not at all. Compare 14318 1.35 C04020 1 02 21002.1121160 582523 295 Ml,,Oe,ar4 93900 143204.5 1 50 21002.1 1 le 5825123 3 50 Extender paerd S6 99 102P31ransldrener 2.25 gram loading, editing and execution with SINGLE before you buy. Super Elf Kit S106.95, High STEP for program debugging which is not in- address option 58.95, Low address option cluded in others at the same price. With SINGLE 59.95. Custom Cabinet with drilled and labelled ROCKWELL AIM 65 Computer LRC 7000+Printer 5389.00 STEP you can see the microprocessor chip opera- plexiglass front panel S24.95. Expansion Cabinet 6502 based single board with full ASCII keyboard 40/64 column dot matrix impact, std. paper. ting with the unique Quest address and data bus with room for 4 S-100 boards 541.00. NiCad and 20 column thermal printer. 20 char. alphanu- Interface all personal computers. displays before, during and after executing in- Battery Memory Saver Kit 56.95. All kits and meric display, ROM monitor, fully expandable. Televideo Terminal $845.00 5375.00. 4K version 5454.00. 4K Assembler structions. Also, CPU mode and instruction cycle options also completely assembled and tested. 102 key, upper, lowercase, 10 Baud rates 24 x 80 S85.00, 8K Basic Interpreter are decoded and displayed on 8 LED indicators. Questdata, a 12 page monthly software pub- 5100.00. char. microprocessor cont. edit. cap. Special small power supply for AIM65 assem. in An RCA 1861 video graphics chip allows you to lication for 1802 computer users is available by frame 549.00. Complete AIM65 in thin briefcase Intertube II Terminal S874.00 connect to your own TV with an inexpensive video subscription for 512.00 per year. Issues 1-12 with power supply $485.00. Molded plastic modulator to do graphics and games. There is a bound S16.50. Super Brain enclosure to fit AIM65 plus power supply 547.50. speaker system included for writing your own Tiny Basic Cassette 510.00, on ROM 538.00, Floppy Disk Terminal $2895.00 Special Package Price: 4K AIM, 8K Basic, music or using many music programs already original Elf kit board 514.95. 1802 software; power supply, cabinet 5599.00 written. The speaker amplifier may also be used Moews Video Graphics $3.50. Games and Music 79 IC Update Master Manual S29.95 AIM65/KIMNIM/Super Elf 44 pin expansion to drive relays for control purposes. 53.00, Chip 8 Interpreter S5.50. Complete IC data selector. 2500 pg. master refer- board: 3 female and 1 male bus. Board plus 3 ence guide. Over 50,000 cross references. Free - Super Expansion Board with Cassette Interface $89.95 connectors $22.95. update service through 1979. Domestic postage allowing users to take advantage of AIM65/KIMNIM I/O Expansion Kit: 4 parallel and This is truly an astounding value! This board has subroutines 53.50. No foreign orders. been designed to allow you to decide how you monitor functions simply by calling them up. 2 serial ports plus 2 internal timers S39.00. PROM want it optioned. The Super Expansion Board Improvements and revisions are easily done with programmer for 2716 5150.00. S-100 Computer Boards comes with 4K low power RAM fully the monitor. If you have the Super Expansion of address- 8K Static RAM Kit $135.00 Board and Super Monitor the monitor is up and Multi -volt Computer Power Supply able anywhere in 64K with built-in memory pro- 16K Static RAM Kit 265.00 8v 5 amp. w18v .5 amp, 5v 1.5 amp, -5v . running at the push of a button. tent and a cassette interface. Provisions have 24K Static RAM Kit 423.00 .5 amp, 12v .5 amp, -12 option. ±5v, ±12v been made for all other options on the same Other on board options include Parallel Input 32K Static RAM Kit 475.00 are regulated. Kit $29.95. Kit with punched frame board and it fits neatly into the hardwood cabinet and Output Ports with full handshake. They 16K Dynamic RAM Klt 199.00 alongside the Super Elf. The board includes slots S37.45. $4.00 shipping Kit of hardware S14.00. allow easy connection of an ASCII keyboard to the 32K Dynamic RAM Kit 310.00 EPROM (2708, 2716 TI Woodgrain case $10.00, 51.50 shipping for up to 6K of 2758. or input port. RS 232 and 20 ma Current Loop for 64K Dynamic RAM Kit 470.00 fully be 2716) and is socketed. EPROM can used teletype or other device are on board and if you Video Interface Kit 5129.00 PROM Eraser Will erase 25 PROMs in for the monitor and Tiny Basic or other purposes. need more memory there are two S-100 slots for 15 minutes. Ultraviolet, assembled S37.50 A IK Super ROM Monitor $19.95 Is available as static RAM or video boards. Also a 1K Super Video Modulator Kit $8.95 Safety switch/Timer version 569.50 an on board option in 2703. EPROM which has Monitor version 2 with video driver for full capa - Convert TV set into a high quality monitor w/o been preprogrammed with a program loader/ bility display with Tiny Basic and a video interface affecting usage. Comp. kit w/full instruc. 60 Hz Time Base Kit editor and error checking multi file cassette board- Parallel I/O Ports S9.85, RS 232 $4.50, Crystal $4.40 Converts digital clocks from AC line frequency , read/write software, (relocatible cassette file) , TTY 20 ma I/F 51.95, S-100 S4.50. A 50 pin Digital Temp. Meter Kit $34.00 to crystal time base. Outstanding accuracy. another exclusive from Quest. It includes register connector set with ribbon cable is available at Indoor and outdoor. Switches back and forth. save and readout, block move capability and S15.25 for easy connection between the Super Beautiful. 50" LED readouts. Nothing like it video graphics driver with blinking cursor. Break Elf and the Super Expansion Board. NiCad Battery Fixer/Charger Kit available. Needs no additional parts for com- Opens shorted cells that won't hold a charge plete, full operation. Will measure -100° to points can be used with the register save feature Power Supply Kit for the complete system (see and then charges them up, all in one kit w/full 4 +200°F, tenths of a degree, air or liquid. to isolate program bugs quickly, then follow with Multi -volt Power Supply below). single step. The Super Monitor is written with parts and instructions. 57.25 Beautiful woodgrain case w/bezel S11.75

TERMS: $5:00 min. order U.S: Funds. Calif residents add 6% tax. BankAmericard and Master Charge accepted. FREE: Send for your copy of our NEW 1980 Shipping charges will be added on charge cards. QUEST CATALOG. Include 28v stamp.

110 CIRCLE NO.61 ON FREE INFORMATION CARD POPULAR ELECTRONICS

AmericanRadioHistory.Com THEF3E'S GOLD IH THEM THAA PAK=

Operation Assist POLY Pñ NNE If you need information on outdated or rare equipment -a schematic, parts list, etc. -another reader might be able to assist. Simply send a postcard to Ooera- lion Assist. POPULAR ELECTRONICS. I Park Ave., New York, NV 10016. For those who can help readers, please re- 12.00'EAs spond directly to them. They'll appreciate It. (Only those items regarding equipment not available from normal AAE MKS EVEiI A 49'EA CALI DM! sources are published.)

200 PC SEMICON SPECIAL, assorted semis of all types. Untested material, 1.3300) 52.99 O 20 -MOTORS MOTORS, asstd. sizes speeds & types, 1.5-12 malls, (.2551A) 2.99 Heathkit model 07 oscilloscope, Need schematic and manual. Saxe Dobrin, 426 W. Marshall O 200 -LONG LEAD DISCS, prime, marked caps, assorted material, (025981 2.99 100 -PLASTIC TRANSISTORS, untested, TO -92, asst. types (02604) 2.99 SI., San Gabriel, CA 91776. O 50 -SLIDE SWITCHES, various shapes. sizes. and types, (027261 2.99 2.99 75 -TRANSISTOR ELECTROLYTICS, erovy encapsulated, asst. values, 1027471 105%, color -coded resistors, asst. values, (03046) 2.99 R & D Instruments 51715 or 1715BR square -wave generator. Need schematic or operating o 250 -HALF WATTERS, 25-91106 VOLUME CONTROLS, various values & types, for Hi -Fi, ele. 1030571 2.99 TN 37415. 2.99 manual. J. Morgan, 3008 Ozark Rd., Chattanooga, O 50 -UPRIGHT ELECTROS, 100%, assorted values & voltages, marked, 103226) 2.99 O 20 -ROCKER SWITCHES, white rockeas, DPDT, solder lugs, 125V 4A, 1033024) 2.99 50 -MINI POTS, pc style, single turn, assorted values, (03345) The Voice of Music model 1484-2 stereo tuner amplifier. Need operating manual, service 2.99 o 20-IUMBO RED LEDS, 3V 10 rnA, IOIPA good material, red dome lense, 103369) F. Griffin, Box 2752, Wichita, KS 67201. board, 1v3625) 2.99 manual, parts list and schematic. Vick C. 3 -SOUND TRIGGERS, sound activated amp, SCR triggered, on 3" 2.99 I 50 -TRANSISTOR SOCKETS, assortment may include; TO -19,5,66,3, etc, (038451 2.99 I 100 -CABLE TIES, 4" non -slip while ptaslic, like Ty -wrap, 1052181 Singer Metrics model SPA 3/25a Panoramic spectrum analyzer. Need operating manual and 2.99 C. 150-FEEDTHRU CAPS, assorted types & sizes, for RF. UHF, etc, 10 5668.1/ schematics. Phil LeMieux Measurement Arts, Inc., Bldg. 24-4, 555 Valley St., Providence, RI I. 250-'. WATT RESISTORS, asstd. carbons, earbo-films, some 5%ers, (05797A) 2.99 2.99 L. 100-PLESSY CAPS, ceramic blocks in assorted sizes & Oases, 1062211 02908. 2.99 30 -HOBBY LEDS, assorted types & colors, mostly dims, some good, (06225) 2.99 C 100-TTLs, 7400 series, incl. gales, lliw-flops, etc. untested, (062261 2.99 Fisher model 203 80 -watt stereo receiver. Need schematic. Charles Harris, 7614 Vicar St., ISO PC.-HEATSHRINK, slip -over type, shrinks 50'4, like Thermo -fit, 106239) New Carrollton, MD 20784. FREE! FREE! Standell Super Artist bass guitar amp and Bell 8 Howell model 34 oscilloscope. Need WITH ANY $30 ORDER, PICK A $2.99er FREE! schematics and parts lists. Billy Happoldt, 3886 Ridge Ave., Macon, GA 31204. 5-8RASS LOCKS, with key, t'," long, for doors. windows, etc. 1062531 2.99 O 258 -.MOLEX SOCKETS, "on -a -strip", make your own pc sockets, 1062551 2.99 2.99 Allied Radio,Knight Star Roamer. Need schematic and alignment information. Larry Cook. 4 -LM -747 OP AMPS, 100', prime, dual linear op amp, DIP package, (n62621 50 -RCA PHONO PLUGS. popular audio/speaker plugs, 100'0 material, (032931 2.99 362 East South St., Richland Center, WI 53581. 2.99 25 -CRYSTALS, assorted types, some H6/U, some frequency marked, 1v62561 2.99 150-SUBMINI IF TRANSFORMERS, asst. may include; osc. antenna, etc. (46259) 2.99 RCA WO -88A oscilloscope. Need owner's manual or schematic. R. Gray, Box 13t3, Donald- 60-SRUARE OHM RESISTORS, prime resistors, asst. values, grab 'em! (06261) ele. 1062631 2.99 CO 30 -MICRO MINI REED SWITCHES, 1" long, for alarms, relay systems, sonville, LA 70346. 2.99 O 200 PC. -CAPACITOR SPECIAL, asst. mylars, potys, micas, eta. 1009. good, (062641 2.99 20 -PUSHBUTTON ALARM SWITCH, SPST, momentary, NC, w/hardware, (062671 ('4eprox.) 1 Ih. asst. screws, washers, etc. 1062711 2.99 I Need owner's manual with fuse requirements and schematic. 500' PC: HARDWARE SURPRISE. ESS Trans -static speaker. 2.99 30.9V BATTERY CLIPS, snap connector, coded, insulated leads, 1062861 Erich Lauft, 78 Pressley Rd., Asheville, NC 28805. 2.99 6 -WATCH GUTS, 5 -function, LED style, assorted sizes, untested, 1062871 10 -HEAVY DUTY LINE CORDS, white, 2 cond. 6 f1. 16 gauge 1062921 2.99 2.99 Potter model MT -24 tape transport, model EC -36 tape transport control and model MA -315 20 -SINGLE PIN LEDS, green, micro style, 7V 10mA, 100'., 106293) 40-LED/TRANSISTOR SOCKETS, "srap-in", 3 pc leads, for TO-5,18,46,etc, (062971 2.99 record/playback amp. Need schematics and service or operating manuals. James Lee, 38 2.99 O 200 -PRE -FORMED W WATTERS, popular values, some 5 & 10 Sers, 1062461 Woodcrest Ave., Ithaca, NY 14850.

Beta Instruments Corp., "Betacom" residence intercom, circa 1951-52. Need schematic. COMPACT CONDENSOR E. C. Alexander, 1425 Marlon Ct., Geneva, IL 60134. BOOM MIKE Space Efficient Practical Overhead "Boom" Design Save dui Calculators Minimizes Sound Coloration Supply Voltage: 9V. Senetdvixy .63 dB w 1 KS.. ityp.I Pre quency Response: 10.15 K Itz Imned: 3.3K . hma n I Khz Size Model Your Cost HEWLET 5/8 idia.: x 1.1/8". With Specs HP.41C Scient 52244.95 Cfih PACKARDT Card Readerl4lC 159.95 Printer/41C 289.95 HP -34C Solent 124.95 ULTRA -SMALL For HP -38C Bus. 124.95 HP -38E Bus 99.95 HP -33C Solent 99 95 LCD CHRONOGRAPH HP -33E Solent 74.95 HP -37E Bus. grog 62.95 HP.32E Adv. Scient 58.95 MODULE faster HP -31E Scient 42.95 -112 Multi -Function Memory Enables Module HP -67 Scient Prog 299.95 3)8 X 1 HP -97 Scient Print 579.95 t:10101101 To Function As: STOPWATCH! HP -92 Bus. Print 39995 "C"stands tar continuous memory ELAPSED TIME INDICATOR! service -ZONE TIMER! $24.50) No. DUAL We carry an enormous stock of HP Cat. accessories. All units come complete. 92CU6403 ALARM CLOCK! One year guarantee by HP.

Call Us TEXAS INSTRUMENTS ñ52áó Call Us TI -59 520995 TI Prog Thermostat 99.95 "CONE -HANDED" PC100C 14695 TI Translator it speaks Call Us USE TI -58C 92.95 TI Computer 99/4 Best Deal TI -57 4895 TI Programmer 5295 40 CHANNEL TI.SS 3595 MBA 5895 TI.5040 94.94 Business Card 35.95 T1-5025 199562.95 Speak & Spell 59,95 DIGITAL TI -5015 Huge inventory of TI accessories on ZIP TI -MOO 4395 TI -5200 Call Us hand at all times. guarantee by TI COMPUTER MIKE SPECIALS Sony new 1981 Bermas SL5600. 320 Seiko watches to choose Iron, retail 11550 00 1095 00 Only Deplane SS 149.95 Sony Betamax 51.5400 97995 Cat. No. Cartier type "Tank-' 177.95 RCA new Selctvisn V0T625 mny CODE ESO Musical Alum Chrongrph SS 17995 new features retail 51400 00 1099 95 92CU6 Worldlier alrmperpt calndr SSI79.95 SONY all TV mods.best dealCall Us $24.88 Calculator Watch Alarm SS 259.95 Craig Translator. besrdeal Call Us Digital Chronograph SS 99.95 NAVTRONICIhght computrs Call Us Alarm Chronograph SS 14995 'Casio calculator watch -New 49.95 Digitally Indicates 40 Charnels Sole Alrte/Chronograph SS 179.95 'Mattel new Horse Race Computr Bright .3" Red LED Display Memory Bank Calendar SS 149.95 best on market 99.95 Alarm Digital Guam 119.95 All models dictating Built -In Digital Car Clock on Multi Alarm goldtone 179.95 machines Call Us 12 Pushbutton Programmable Keyboard Divers 500 Ft quartz 60581 199.95 'Place your order now for All The -Controls In The Palm Of Your. TI watches 70 models also Casio May June delivery and Inertia watches Hand Casio Sharp -Canon Bor s Chess games -Victor Sanyo-Pearlcorder With 6' Coiled Cable & Plug Polaroid-PanasonicAmana-Utton.AplAtan Navtronic and others

all Prices are 1 e b LA Add 54 9514 shipping handheld talcs in LISA CA residents add es sales tali We will beat any advennedpneed the eonrpeK.on nao tn. geed. on hand SEND FOR FREE CATALOG HOW TO ORDER Goods sublect to availability Ask lar our 130page catalog We honor MASTERCHARGE. VISA. check, and C.O.D. by or ' Call Monday mm Saturday. 4AM to 6PM. muter anrge 1257 downiMinlmum Order:510 Order phone VISA' A name & month Outside CA. lull Tree 800 mall. state Cat. No. deacrlptlon, 421-8045 add In CA. Cell below e's of magazine. POSTAGE: USA: add $3. CANADIAN; mail POLY PAK( S5. FOREIGN: add S10. (US funds). Excess will be OL9mplc SALES comPAnsi. Inc. P.O. BOX 942. ES returned. OPEN ACCOUNTS: (must be listed & rated In MA Dun & Bradstreet) Net . 30 PRONE: 16171 245.3828. r216 South Oxford Avenue ; P.D. Box 74545. Los Angeles, CA 9008E SO. LYNNFIELD. 01940

12131381-3911 or 12131311-1202 Telex 67-3477 1 '

CARD 113 MAY 1980 CIRCLE NO.50 ON FREE INFORMATION CARD CIRCLE NO.60 ON FREE INFORMATION

AmericanRadioHistory.Com SD Systems Z-80 STARTER SYSTEM HYBRID AUDIO POWER AMPLIFIERS Matching PET2001 professional computer 7' The 280 Starter Kit by SD Systems uses the power. P/N Transformer f t lull 2800,p ropmcessor as the heart of the complete ac 51.10106110W) 5 6.95 TRIO S 7.90 microcomputer single board. Learn a step -by. itre. -r SI.1020G120WI 513.95 TR20 510.90 stop Introduction to microcomputers with a keyboard ASI'81Socket for above) .95 and display, audio cassette interface, PROM pro- put e grammer, wirewrap expansion 51.1030G130174 519.00 TR30 512.90 =wen area, 4-channel Counter Timer and on Board RAM and PROM. Com- :.gal, / SI.1050GI50W1527.80 TR50 517.90 44- plate Operation and Instruction Menuel included. ASI.101Socket for abovel .95 a .1 ZBUG Monitor in ROM Note: On Transformer can power two audio emplifi.N. Modalimememiss 111111"1.171.111.17- CBm 2040 CBM 2022 Kit $340.00 Assembled & Tested $450.00 Modal Capacitance Meter CBM 2001 MC3061 P 5 3,26 MC4052P S12.72 Easy to use - plug in capacitor, push PET 2001.8N Computer 8K bytes, large keyboard MC3062P 3.26 MC4053P 12.72 range y :' w/separate numeric MOTOROLA road pad and graphics $795.00 MC3360P 3.50 MC4054P 25.82 button and tho value to 0.1% \`\-_e.iF!" -1 0.5 in. liquid ry f PET 2001-16N Computer 16K bytes, large keyboard with separate numeric MC1408L6 $ 2.65 MC4061 P 7.50 MC6800P 10.97 crystal display Exclusive pad and graphics 5995.00 MC1408L7 3.20 MC4024P 3.95 MC6802P 16.79 ".3cherge/,3volt" meeeur ,a CBM 2001.168 As Computer above but has standard typewritter keyboard. MC1408L8 4.97 MC4038P 11.55 MC6808P circuit (patent pending) holds 10.. 1% No graphic keys 13.35 $995.00 MC1439L 2,90 MC4039P 11.55 MC6809P m basic accuracy for full year. PET 2001.325 Computer Identical to PET 2001.16N eseept with 321( bytes 35.84 Up to 200hrs operation on standard 9V Sett. _ of memory MC1456P1 1.32 MC4040P 6.95 MC6821CP 10.89 $1295.00 8 eery pushbutton ranges cover 0.1pí to CBM 2001.328 Computer Identical toCBM 2001-168 except with 32K bytes MC1458CP1 .66 MC4041 P 11.65 MC6840P 9.90 ! 's' 1999 microfa reds. t .r of memory $1295.00 MC1488L 1.42 MC 4042 P 5.30 MC6845P 33.67 .. Bost of all it's easy on the budget - CBM 2022 Printer 80 column dot matrix printerwnhplain paper or forms MC1489AL 1.42 MC 4093 P 5.30 MC8311 P 5.00 only handling tractor leed. Full graphics 5795.00 MC1489L 1.42 MC4044P 4.50 MC14408PD CBM 2023 Printer 12.74 80 column dot matrix printer. Plain paper printer MC1494L 6.62 MC 4048P 11.55 MODEL 938 $149 with lull graphics MC1A411P0 14 61 5695.00 MC1808P 1.07 MC 4050P 14,77 CBM 2040 Duel Floppy Dual drive Intelligent mini floppy system. MC14433P0 17.91 MC1809P 1.07 MC4051 P 341 K net tiler storage capacity $1295.00 14.77 MC1449oVP0 5.66 C2N External Cassette Cassette player/recorder to use with Intersil LED or LCD PET 2001/8/16/32 $95.00 LIQUID CRYSTAL DISPLAY en PET to IEEE Cable Use this cable to connect your floppy or printer 8038CP 31 DIGIT PANEL to any CBM Computer $39.95 Function Generator IC r+ High Contrast Ratio IEEE to IEEE Cable Use this cable when connecting more than one per 53.90 each 1 e,ileetnr. Wide Viewing Angle ipheral to any CBM Computer 549 95 ,I METER KITS User Manual 60 pages covering all facets of user operation. programing . - ' 0.5 in. Digit Height BUILD A WORKING DPM IN le HOUR WITH and I/O for PET Computers 59.95 2708 EPROM ULTRA Low Power Consumption THESE COMPLETE EVALUATION KITS 510.50 ea LCD106 Professional Keyboard Kits! 514.50 rh Alp aearte.n put LCO ",apta pe m e 11061 LEO .pay Ili the Imp. %ice movAe ep Models 753 & 756 ASCII Keyboard Kits SORCERER COMPUTER FEATURES - 40 0 caPAM Ouai /0 - 30 For Hobby or OEM Microprocessor Users Camu Lines o -pa Ñ -o rH . ICL7106E V ILco1...529.95 ICL7107 15E01 .520.95 ónw nat. Full 128 Character ASCII (766) 53 Key., popular ASR.33 2 Crepe murbnr Ed4.Cr! Canna. bon to 5100 Bus- 5nai and ParaII.I itch format Ruggnd 0.10 P.C. Board Td-mode (753) MOO en. DP10057 taKSorwrer S115a.0 MOOT rdw0 IyCae 4.95 Digit - 10 MegaHertz coding TwoK.y failnver MOS/TTVDTL Compatible out - Video 59.00 50°j ÓPaenÉpMmM °P3001 Magv Puts Shift end Alpha Laek17661 Level end Pulse Snobe17561 nal9.951106 Intersil 8Universal Counter Kit Keycap. Cunom 3 Ua.r Defineble K.ys17531 Seiecteble DPiopOOJ 99.W PSWi OÉ.IwnminnlUnlrM.nu.I11.95 Parity Low Bo.. N ywnchw And Mu. Morelli Kit Includes: Resistors pv74°0001 GaditPi Ñeeorréa've 4.95 DPSW i ward Prowanp Mawal ii.95 1CM7226A1DC IC 7536 53 Key phone style keyboerdKit... $65.95 Capacitors 753A Some es above assembled $79.95 NEW KIM -1 MICROCOMPUTER 10 MHz Quartz Crystal Diodes 756K 56 Key Full ASCII keyboard kit 569.95 SYpM -1 (8) 7 Segment .3" LED Displays Switches 756A Same as above assembled $82.95 PRICE 701 Plastic enclosure for 7531756 515.00 PC Board IC Socket 702 Steel enclosure for 753/756 $29,95 Fully Order Part Number ICM7226AEV $59.95 753MF Mounting Frame for 753 $6.95 Assembled 756MF Mounting Frame for 756 S6.95 & Tested Dr a / . \ end your check r Money Order to AP Products $17900 P.O. Boo 2208P, Culver City, CA 90230. Californiai resi- x+ '+q . $239.00 dents add 6% sales tax. Minimum Order: $10.00. Add Including The all -new line of ACE kr0 ct o -Rat $1,00 to cover postage end handling. Master Ch ergs end KTM-2 CRT/TV Kybd Teeny 5349 Documentation Vise welcomed. Please Include your charge carol number, Interbenk All -Circuit Evaluators number and expiration date. Power Supplies from ADTECH POWER PHONE ORDERS 1213) 641-4064 WITH TUCSON CULVER CITY SANTA ANA POWER Model Vdc Amps Model Vdc Amps PORTLAND 9.425.14 S2ne 5.4e POWERACE 103 POWERACE 101 POWERACE 102 APS 5-3 5 3.0 APS 5-6 5 6.0 91220 923103 $124.95 923101 579.95 923102 5124.95 APS 12-1.6 12 1.6 APS 12.4 12 5.0 16021 eel 2W I11n `ltió3sáá 21 150]1 25.4541 Triple.output power The general purpose The complete digital APS 15.1.5 15 1.5 APS 15.3 15 3.0 CANADA, supply for protoryPing model for protoing proroeyping lab with APS 24.1 24 1.0 APS 24.2.2 24 2.2 cñÓiBC SUNNYVALE ATLANTA a/I types both linear and digital ! mu i0. FREE logic probe built 1-9 10 up 25up 1.9 10 up 25 up 2649 Pluemene circuits. ini $37.25 $35.55 S34.05 S59.75 $57.10 $54.65 IMO 243412100. ."114/-11.=1» fetal 5aáiyáe

FREE WIRE WRAPPING GUN Get O.K. Model BW'630 Battery Wire Wrapping Tool described be/ow FREE with your ORDER DESK: 800-325-0101 Purchase of 5100.00 worth of precut pre -stripped wrapping wire at listed prices. Our IN ORDER TO SERVE YOU BETTER, WE HAVE INSTALLED NATIONAL WATS WHICH ARE standard Volume Discount Schedule is, of course, also applicable to your purchase. SERVICE ATTENDED 7:00 AM TO 9:00 PM TIME) MONDAY THROUGH FRIDAY; ANO PM Please specify CATALOG NO. 99-00630 for your free wire wrapping too/. THIS OFFER (CENTRAL FROM 8:00 AM TO 5:00 ON EXPIRES APRIL 30,1980 SATUROAYS. WE INVITE YOU TO CALL AND CHECK STOCK BEFORE PLACING YOUR ORDER, FOR CASH CUSTOMERS WE HOLD THE ORDER PENDING ARRIVAL OF CONFIRMATION ANO PAYMENT

740 . . 50.43 74196 , 5087 7415114 5038 74507 . 50.35 74042 .. 50.94 4010 ., - 5043 4512 .,.5098 ' WIRE WRAPPING TOOLS , 74 7491 , ..0.58 74197 ..087 ML5I23 098 14503 , 035 74048 ...1.27 4011 ...0.22 4516....122 7491 . . .0.43 . 1!15 7415125. 0,48 , .036 74c71 4012 O.N., Mnnei 8W630 (011ero operated wrapping tool, uses VECTOR'e Model 0180 SIItN.W.op nanaes 1300 74198 7a504 .. .0.71 4518-...1.13 7400 50 15 7493. 74199 74LSt26 0.48 14505 ..O.J6 74C74 two sire "C" looo MI lo . PoyNWen wire for w wraps around ..043 ...0.48 401J 4519....062 . 1 7401 1494 . . .0.65 74251 7415132. .080 74509 , , U.38 7C76 . . .0.71 a014 4520 1.13 aorlesl No. 30 ote around .025" .025" s Ts. to Mu n Me wire tefore nm 0 1402 .0.11 ]495. 141.5136. 74083 . 1,37 . 1 Th rsdiked" has ...aiming and aml can Oa ..065 74283 ..120 0.38 14510 ..0.35 4015 0.95 4521. 63 unetand Ixmllw y-Citaprecut 7403 .0,1) )496. ..0.65 74290 ..O.B9 74LS138, 0.93 74SI1 .,038 74C85...1,37 4016 , 0.39 4528... pr ePoomnak required. It e pate with .wo10' 086 7405 Q16 7491. 74293 7415139. 093 74515 74C86 4017 104 4539 , CATALOG a 50.. 2500630 534.95- P103 KndeTun1. ..245 ..0.89 O18 .. 0.49 I10 1406 74107 , , , CATALOG NO. 73-91800 525.00 .0.29 74298 0,92 7013151. 074 14520 .0.35 )4C89 .395 4018 4555... 0 6 1406 74109 74365 . 062 7410152.. 0.74 70522 )4C90 4019 0 86 0.0:s Model BW7628 toolr, same w ow, but le for 032 ..0.36 ...097 0.39 4556... 1401 74121 ,.0.34 74366 . 0.62 7413153.. 14530 74C93.. 0.97 4070 1,13 4582.. - ,os ,iee Not 26 to 28 ...is VECTOR'. Model P160 4T 'e a lanere °owere7 Mon spear OM ,.035 088 7409 74122 . .019 ]436) . .0.62 )415154. . 1,09 70540 . , 0.35 74095 . 1.09 4021 . , t.13 CATALOG NO. 25 02628 539.95 Mat rn Mode P180 She N Wrap 4584... 0 74 409 74123 74368 ..0.62 7415155.. 0.74 14560 ..0.38 7aC107. 0.69 402 . abovewool high n s wrapping app catiohns 1/4. .095 4702....710 7770 )4125 O.K.'s kloiel WSU.30M Men t ..0.39 74L5156..0.74 74565 .,038 74C151. .189 4023 . .0.22 4703... 825 wee maiminga.nc n N. Cads and rech9eir out:. n mat stow No. 30 wue, makes CATALOG NO, 23 86490 599.50 7.154... 4024 4704... 730 threetool 1413la 74LSxx "Model.- wraps and even unwraps previeuato 000pel áux ..oss ia1sise..o.< áse...o58 ác 5...i,s9 4025 , .0.71 4705... 925 )413 )4101 ..079 74L500. 5027 7415160 , 1,01 745)8 740160 , 1.11 4027 4706 , P ants VECTOR'$ Modei P160.471 um« es *rove. Put ir ...058 .039 ...9.75 7414 74145 ,.0.69 74LS1611.01 , CATALOG NO. 75-1600 57 95 Mneattis m 110V AC loe conbwu. operarrM 74L501...0.27 74S86...058 74C161 ..1,17 4078 ,0R8 4720....695 7416 )nl4) CATALOG NO. 2380491 599.50 1.60 741502...0.2) 7410162.. 1.01 745112 ..0.50 )4C162 . 117 4029 , .1.13 4723.. . 0,93 1411 741548 1.29 74L603...0.27 740,5163..1.01 745113 24C163 I 17 4030 O., Model WSU.30 is obe same o dove. hot makes -.058 , .0.29 4724.. .129 )47U . 019 74150 , .0.89 741504. , .0.28 7415164. , 18t 145114 . .050 740164 1.09 4031 , .2.97 Remlar" ' Mos...., wrap.. VECTOR'$ Motel 6.184 Slrt.N Wrap 774, 0 loot is the same 4725....395 7423 74151 NO. .0.59 )4L505. ..0.28 7415168, 1.13 745133 , .0.18 7aC165 1.09 403C . 2.)5 4014 .. 090 CATALOG 7315000 56.95 as Mode P180 Tool descrihed abate,r rl ta ca 1075 74152 .0.38 . 1500 raed Ta,t.l wee lo Whrew* edab0Ny ..0.59 141508. 7415169, 1.13 745134... 0.38 74C173 . 1.29 4035 . .099 40085 137

7426 )4153 1 7415170.. 122 , 15 . VECTOR'. Model P178.1 INIong Penchi etudes and wrap) CATALOG NO. 2381840 530.00 .0.78 145135 .0.49 740174 4040 .0.99 40098 . 0.54 143) 74154 741510, 0.77 74L51)3..I.J3 411d1 . 40106 insuiaien r n leads obblm .. )45140...0<] ]4C1)5...115 018 0.90

7430 . , . , ]4155 .0.69 741315. . .0,17 7415174, 1.05 145151 0.69 74Ct92. . . I 37 4042 . .0.78 áO160 117 Conn ee by solder 1 750, VECTOR', Model P184.4T Is a bat n v tow.rm mono )43z , , . 74156 .0 69 241520. 0.27 7415175. .0.83 745t53. . . 0.)5 I4C193. , . 1.37 4043 0161 1,1) whenapplied, oMel m tim wader Maitool Incarpor M1nouction. eI P184 eSlit.N Wrap Tool to 7437 74157 ..0.64 )4L521...07) 74L5181..750 4044 , 00162 t is under the roan 1 :o Pond me oncpon. Complete .5,16 N,.Cad. and 045157... 075 74C195...108 ,0.69 .. 1,17 7438 74158 , , , CATALOG NO. 23.81781 57.95 d. 0.64 741321. .. 0.27 7413190.. 1.17 745158 . 0.75 74020. . . 7.50 4046 , , 1,79 40163 ..1.17 74160 . . 1,17 , . 4047 . , 40174 CATALOG NO. 2388490 5105,00 .08) 741526. .0.32 7415191.. 74510 .3.)5 740221. . 189 1.99 115 )5414394° I416t 7aL5192. . . . VECTOR'. Model 550 K.1 include, above mentmnel wrung 741577...0.27 .09) )45259. 1.15 )4C01. . .O.nB 4048 .0.95 40175 ...115 7441 O BS )nt61 ..0.81 )4L530...0.27 7415193.. 0.97 745780...2.25 4049 . P ence. plus a Verrorbnard and host of runes untul VECTOR's Model P184 -4T1 Is AC PleWefedl version nl 7.902.. 0.48 039 40192...131 442 ]A163 above la u, nowaune ...049 ..08) 741432... 0.32 74L5194,,0.97 145781...3.70 740903... 0_59 4050 40193. 137 7443 )44164 . 0.87 14L537 .0,32 7415196. .0.85 . 160 )4C904. , 4051 . . 40194 1 CATALOG NO, 23 5500 513.90 CATALOG 5101 23 88491 5105.0 ...0.69 745300. 059 1.19 ., 0 7444 .,,069 74165 ..081 741538 0.32 7415197..085 74530...190 74C905 .,6.00 407.. .1,19 40195 . - .108 7445 )n166 741S40, .0.21 7415721.. 190 745310, .. 2.85 70C906... 0.59 4053.. PRESTRIPPED WRAPPING WIRE 7446 )416) . 195 )aL542...0.66 7415253, .0.99 745312.. 1.05 74C907... 0.59 000 7447 I4110 LINEAR This month I,C C Oilers the widest seleclpon of In order to Weedy pie 0010, of insulation. ..1.55 741547, .028 7415257..0.14 745316...200 74C908...1.19 4066.... 0.78 7448 74173 . 1.20 741548. , .0 76 7016258, .0.74 745341. . . 4.10 740909.. 1,78 4069 76 NE501A . precut aryl pre serrpped AWG 30 wrapping yme please replace the "5" en price table below with lire ...0 560 74174 , , . 7450 ...0,19 o R8 741551. .0 27 74L5266, .0.38 145347. . . 1.20 74C910. . 4060.... 0.46 SE540L available anywhere. The Kynar insulated wire hasa proper color number from the following table: .6.0 ..6.0 7451 74175 078 741.4. . 0.27 7413279.. 0.58 74S343.,.495 740914. 1,19 4070.... 0.22 NE5609 . 2 50 Ile9 Of and is available en len contrasting 105°C 7453 .. 0.19 74176 ..078 )41.555...027 74L52133, 0.99 145346.. 1,25 74C918 149 4071 0,22 NE5618. 250 lot .... colors a$ tracing. There . of are lour package BLACK 0 GREEN 5 7454 74177 . ...0.19 0.78 )4LS)3...0.30 7410790. 064 745362 .2.15 700925. 780 4073... 0.22 NE5654 . 120 may Ilse 1 buy only quantities that 7459 . 19 0 you you BROWN BLUE 6 . 0 14179 180 741370 , .0.38 2415295. 099 145387 4.70 74C926. , . ) 80 407155 ....011 u4I031/ 028 need. Each piece is stripped 1.0" born each end and RED 2 VIOLET 7 7450.. .0,19 7410 069 741576. .038 7415365. .066 74C927... BO 4077.... 1,29 04)104 029 Is packaged in it-tight re Cable Manic tune to ORANGE 3 GRAY 74181 195 741578...0.18 7415366, 066 74Cxx 745928.,.7.80 4077 ...0.39 u4711A 0.39 prevent C0,10510 nofn the stripped ends. YELLOW 4 WHITE 9 7412. . 0.2e 74182 078 )41583...0.18 7413367. 066 á078....0a9 vA7234 . 0.49 7413 ....0.29 74184 ,195 741585.,.097 7415368, 066 WOO 50.24 oat ....0.22 uA733A 066 74185 INSULATED PACKAGE PACKAGE ,.195 741586...038 7413386..038 74002e2 .0.24 4095....2.69 uA7414 .. 0.25 OF 50 OF 10 PACKAGE OF 500 PACKAGE OF 100 7475 .. 048 74188 . . . 3.25 74150. . .0 56 74L5390. . 169 74Co4 ,026 4000 S0 22 4099....2.75 u4748V . 0.35 LENGTH CATALOG Na PRICE CATALOG NO, PRICE CATALOG NO. PRICE CATALOG NO. PRICE )4)6....0.31 7410 .. .095 )41593. . 0.56 741540. 1.49 70000 .0.25 4001 0 22 403 ...099 N55964,,069

30.1030 5480 74191 . . 301020 500 8160 301000 301050 5880 7080. ..0.49 .0.95 )41595. . .087 7415670, .2.33 74010 4002 072 4599 ... 0.10 15" 30.1502% 094 30 1503% 168 30.1504% 504 30.15050 024 7482 .... 0.55 74192 . . .0 0 7415107 .0.38 74010 ,090 4006 , 119 4503 0.98 20" 30202% 098 30-2030 30.20000 525 30.20050 963 7483.... 0.59 74193 . . .0.80 74L510 0.38 74Sxx 74020 . 0.25 401....0.22 450....099 3 5" 30 2502% 1 07 30-25030 1 83 30.2504% 5 49 307505% 10.06 74194 .,.08) 7415112..0,38 70030 4008 . 0.79 45110....1,13 ] 0" 30.302% 105 30 3030 190 3030040 5 70 30.3050 10.45 7.6 ...0.27 74195 . . . 0.87 )4L5113. . 0.18 7450. SO 35 114032 .025 4511....104 ]5" 30-35020 1.14 30 3503% 198 30.3504% 594 30.3505% 1089 40" 30402% 118 30.4030 7.05 304040 6.15 3040050 11.28 VOLUME DISCOUNT SCHEDULE I STANDARD SHIPPING CHARGES 45'' 3045020 122 30.4503% 2.13 304504% 6.39 304505% 11.72 INTERNATIONAL COMPONENTS 1.r/undue Tort DISCOUNT Ir 50' 30.50020 1.25 305039 7X1 30.5004% 6.60 305005% 121° sur rootawrueen S 001-5 9 1 0 y 000-41-S 4 60" 306020 133 30.6003% 73x5 30,60040 705 306005% 1193 add 5100 CORPORATION S 1800-$ 24ºº LESS 31 S 501S2499 aMS100 e" 30702% I 45 30-7030 250 13 75 250 30)040 30.20050 O 2500-39006 LESS 10x S 2900-049.99 w0,S073 I 57 80' 308070 30.8030 265 3080040 795 30.80050 1458 10000-5499 99 LESS 105 S 3000-509ºº andSd50 VISA ' 30.9020 30.9004% 8.40 em ate -59ººº2 10 309030 1540 LESS 20, rGCO . 70 30905% S Up NO CN4RGE JCyÍ 100' 30.10120 1.68 30.1013% 295 301014% 8.85 30.1015% 16.21 ,Ioapandm Up LESSn% r. wl enany.a ,rclwh row 15.0' 30.1512% 205 30.1513% 370 301514% 1110 30 1515% 20.35 P. 0. 807E 1837 COLUMBIA, MO 65205 1314) 474-9485 CIRCLE NO.35 ON FREE INFORMATION CARD AmericanRadioHistory.Com Popular Electronics SPECIALS!! !SPECIALS! ! ! ADVERTISERS INDEX Soldertail 16K Dynamic FAMS: 8/$87.20 sockets: Expand memory in TRS-80'-I and -II, as well as machines READER made by Apple, Ex dy, Heath H89, newer PETS, etc. Low SERVICE NO. ADVERTISER PAGE NO. 14 pin 50/$4.95 16 pin 50/$4.95 power, 250 ns (4 MI -z). Add S3 for 2 dip shunts plus TRS-80' 18 pin 50/$4.95 installation instruct ons. 20 pin 40/$4.95 TRs-BC Is a trademark of the Tandy Corporation 2 Active Electronics Sales Corp. ....109 24 pin 50/$4.95 3 Amelect, Inc. 97 28 pin 50/$4.95 Transistors: ']en purp NPN (sim 2N3904) 100/$7.95 4 Ancrona Corporation 114 5 APF Computer Cover 4 40 pin 20/$4.95 '7en purp PNP (sim 2N39061 100/$8.95 6 Apple Computer Cover 2 7 AP Products 12 Audio Technics, Inc. 90 IMSAI spacing 5-100 soldertal edge connectors 2/$5 Others: MA1003 12V DC auto clock module with matching case $19.95 Bullet Electronics 104 8 BYTE 89 Camelot Direct 53 9 Chaney Electronics 108 THE FIRST OF A NEW GENERATION Classified Our innovative Z -80A CPU board is tru- compatible extended addressing at 116, 117, 118, 119 Advertising S-100 FD (hex). Cleveland Institute of ly the f rst of a new generaton of port Electronics, Inc. 26, 27, 28, 29 bus equipment ... a generation that's These advanced features give you the 70 Cobra Cover 3 designed to accomodate multi-user powe- you need for future expansion, 1 Communicatlons'Electronics 98 setups and other high level industrial, as well as the system flexibility that 10 Communications Technology Group 119 scientific, and commercial applications. come; from superior design. Yet, the 11 Components Express, Inc. 96 price s competitive with boards that do 12 Computique 108 This '_Pu card contains all standard much less: $225 unkit, $295 assm, and 13 Concord Computer Components ...86 Z-80 features, but also features full com- $395 CSC. 14 Creative Computing Magazine 97 pliance with all proposed IEEE S-100 bus 15 Custom Craft 86 standard, provision for adding up to 8K Ne>.t month, we'll unveil our 16 OAK Industries 15 of EROM, power on jump and clear, on- 8085/8088 dual processor board and 17 Delta Electronics 115 board fully maskable interrupts for the Spectrum color graphics board. For 18 DigiKey Corp. 105 interrupt -driven systems, selectable furthar information, send an SASE 19 Diocwasher 20 insertion, non- (please do not call our phone lines '20 DSI Instruments, Inc. 30 automatic wait state - maskatle interrupt, and or -board IEEE are b Jsy enough!). Educational Calculator Devices 99 22 Eico - 98 23 80 Microcomputing 92 TERMS: Cal res add tax. Allow 5", for snipping excess refunded. Electronic Technical Institute 88 VISA. /Maste'Charge' Call 14151 5620636 ;4 tours. COD OK 25 Enercon 85 with street address for UPS. Speoal prices good tnrougn cover month of magazine wnrle supplies last mbar prices are sub- Fordham Radio 108 lect to charge Without notice. Add 51 handling to orders Supply unoer 515 26 General Engines Company 119 GODBOUT ELECTRONICS 27 Godbout Electronics, Bill 115 If you're -eading this magazine, our Catalogue Bldg. 725, Oakland Airport, CA 94614 Grantham College has something You need ... send For it to- of Engineering 99 day (foreign requests add Si tc help defray 28 Guardian Electronics 13 Postage) lr CIRCLE NO.27 ON FREE INFORMATION CARD 29 Hardside 100 30 Hayden Books 102 31 Heath Co. 69 69 Heath Co. 40 32 Hobby World 104 29 Hustler 85 Convert Your Car Into A Concert Hall! 33 Illinois Audio 92 AUTOMATIC RADIO 34 Information Unlimited 90 35 International Components Corp. ..114 w MADE BY THE AUTO RADIO 36 Jameco Electronics 106, 107 SPECIALISTS!! 1 37 J&R Music World 102 f JS & A National Sales Group 1, 9 I sa.oa,tr_1 '2 Models Ole s z 'C[:. xi May 38 Kiloband Micro Computing 100 Vary r 39 Lifeboat 101 -" I'USH BUTTONS 40 Maxell Corp. of America 54 MICROCOMPUTER MART 101 AM -FM 41 Media Marketing 94 Mercury International 76 42 McIntosh Laboratory, Inc. 10 95 43 National Guard 39 $100 AM'FM Netronics R & D Ltd. 45 Netronics R & D Ltd. 95 SHPG. 44 Novation, Inc. 6 No. 16, 17, 18, 19 Delta 5785P NRI Schools UNBELIEVABLE RADIO 45 Ohio Scientific 5 47 OK Machine & Tool Corp. 35 FACTORY CLOSEOUT! One of America's NEWS ITEM! Auto hi-fi has become as so- largest manufacturers of auto radios has 48 OK Machine & Tool Corp. 7 giv- phisticated as home hi-fi - and nearly as ex- 49 OK Machine & Tool Corp. 87 evn up. We've been fortunate in acquiring pensive. You can spend $200 for simple 113 the last auto radios in production. These components-which means hi-fi can be out 50 Olympic Sales are 51 Omnisonix 24 AM -FM sets....designed for new cars. All of reach for Many folks and 2nd cars. If you are tested 100% operational and come with want hi-fi FM, you can start with the pur- 52 Paccom 90 knobs and push buttons. Ideal for installing chase of a $100 radio for a mere $19.95... 52 PAIA Electronics, Inc. 98 in your auto, van, camper, boat, truck. This price will not last long-order today! 54 PAL "Firestik" Antenna Corp. 98 55 Parts Masters, Inc. 92 56 Peoples' Computer Co. 82 57 Percom Data Company, Inc. 2 CB Transceiver SBASETATION $1695 58 Personal Software 11 BASE operates on max. power No. 2 FOR $32. 59 Pioneer Electronics 22 allowed by FCC. Transmits & re- 5788W 60 Poly Paks 113 ceives on 49.860 MHZ; is crystal MAIL-ORDER ADDRESS controlled. Tunes all 40 CB than- i 6/. - 61 Quest Electronics 110 nels with superhet q^'a^+"". ncvr. Swing -up mic., Radio Shack 70 squelch control, 30" 62 Rainbow Computing, Inc. 74 antenna. ] 2-transis- FREE:ELTA 63 RCA Home Computer 33 tors-battery $40.00 (IZO -PG. 64 Riehl Time corp. 75 power. VALUE 65 RNB Enterprizes 84 SURPLUS CATALOG/ ELECTRONICS Sabtronics International 14 176 SECOND AVE. Sharper Image, The 23 66 Shopsmith 91 WALTHAM, MASS. 71 Solarex 99 L _W:d 02154 wxa.c.,, Minimum Order $8.00 68 University of the co~ 4fJ Trees, Press 60 _vv TEL (617) 388-47155 When in our area, northeastern Mass. or southern N.H. visit our retail at 7 Oakland St., Amesbury, Mass. CIRCLE NO.17 ON FREE INFORMATION CARD AmericanRadioHistory.Com Electronics Classifie" REGULAR CLASSIFIED: COMMERCIAL RATE: For firms or individuals offering commercial products or services, $2.75 per word. Minimum order $41.25.EX- PAND-ADe CLASSIFIED RATE: $4.10 per word. Minimum order $61.50. Frequency discount: 5% for 6 months; 10% for 12 months paid in advance. PERSONAL RATE: For individuals with a to personal item buy or sell, $1.60 per word. No minimum! DISPLAY 1 CLASSIFIED: 1" by column (2-114" wide), $330. 2" by 1 column, $660.00. 3" by 1 column, $990.00. Advertiser to supply film positives. For frequency rates, please inquire. GENERAL INFORMATION: Ad copy must be typewritten or clearly printed. Payment must accompany copy except when ads are to be billed on credit cards - American Express, Diners Club, Master Charge, VISA (supply expiration date) or when ads are placed by - accredited advertising agencies. First word in all ads set in caps. All copy subject to publisher's approval. All advertisers using Post Office Boxes in their addresses MUST with supply publisher permanent address and telephone number before ad can be run. Advertisements will not be published which advertise or promote the use of devices for the surreptitious interception of communications: Ads are not acknowledged. They will appear in first issue to go to press after closing date. Closing Date: 1st of the 2nd month preceding cover date (for example, March issue closes January 1st). Send order and remittance to Classified Advertising, POPULAR ELECTRONICS, One Park Avenue, New York, N.Y. 10016. For inquiries, contact Linda Lemberg at (212) 725-7686.

FOR SALE SpeakerGuts. SATELLITE TV FREEI Bargain Catalog - I.C.'s, LED's, readouts, fiber op- FOR tics, calculators parts 8 kits, semiconductors, parts. Poly The absolute latest in THE HOME Paks, Box 942PE, Lynnfield, Mass. 01940. advanced speaker techno- Our receiver lets you get logy. Wave Aperature'" over 75 GOVERNMENT and industrial surplus receivers, transmitters. Drivers, the Patented channels of televi- snooperscopes, electronic parts, Picture Catalog 25 cents. Nestrovic Woofer System, raw sion directly from earth - rla.lN1- 14 Meshna, Nahant, Mass. 01908. speaker components selected for orbiting cable TV satellites!: their excellence. Horns, crossovers, subwooters. woofers. HBO, Showtime, super sta- LOWEST Prices Electronic Parts. Confidential Catalog Free. midranges. horn and dome tweeters. Over 30 in all. Build KNAPP, 4750 96th St N., St. Petersburg, FL 33708. your own speaker system and we'll provide top quality tions, sports and movies speakers and design information. Send for FREE 48 page from around the ELECTRONIC PARTS. semiconductors, kits. FREE FLYER. color catalog from the largest. most experienced speaker world.li_. Large catalog $1.00 deposit. BIGELOW. ELECTRONICS, kit manufacturer in the world. DON'T DELAY. Write today! Bluffton, Ohio 45817. Sick of Network TV? RADIO- T.V. Tubes - 49 cents each. Send for tree catalog. ("LI- Buy Complete or Cornell, 4213 University, San Diego, Calif. 92105. r.tYR. Build our kit and Dept.eokeiled 178 735 N. save! Northlaké Way AMATEUR SCIENTISTS, Electronics Experimenters, Sci- Seattle, Washington 98103 Our 24-channel receiver provides "studio quality" ence Fair Students ... Construction plans Complete, in TV reception. Easy to Install! Ultra low power con- - sumption! Brilliant cluding drawings, schematics, parts list with prices' and RECONDITIONED TEST EQUIPMENT $1.00 for catalog. color! Works anywhere! FCC licensing no longer required. Order today! sources ... Robot Man Psychedelic shows Lasers WALTER'S TEST EQUIPMENT, 2697 Nickel, San Pablo, CA - - - Complete details covered In our Home Earth Sta- Emotion/Lie Detector Touch Tone Dial 94806, (415) 758-1050. - - Quadraphonic tion manual. Send $7.95 today (refundable against any Adapter Transistorized Ignition Burglar Alarm Sound purchase), or call: - - - NEGATIVE ION GENERATORS AND Meter ... over 60 items. Send $1.00 (no stamps) for complete ACCESSORIES. (Kits). Fascinating details $1.00. Golden catalog. Technical Writers Group, Box 5994, University Sta- - Enterprises, Box 24-hour C.O.D. Hotline 1282 -PE, Glendale, Arizona tion, Raleigh, N.C. 27650. 85311. (305) 869-4283 SOUND SYNTHESIZER KITS- Surf $16.95, Wind $16.95, SPACECOAST RESEARCH Wind Chimes $22.95, Musical Accessories, many more. Dept. H, P.O. Box 442, Altamonte Springs, FL 32701 Catalog free. PAIA Electronics, Box J14359, Oklahoma City, 1 Telephone'Listening'Device OK 73114. NEW ELECTRONIC PARTS. j Recórd telephone conversations in your Continuously stocked. Stamp office or home. Connects brings catalog. Daytapro Electronics, 3029 N. Wilshire TELETYPE EQUIPMENT: Copy Military, Press, Weather, between any 915 Ln, Ar- E cassette or tape recorder and your lington Hts., IL 60004. Amateur, Commercial Transmissions. Catalog $1.00. 0 telephone or telephone LINE. Starts - WEATHER MAP RECORDERS: Copy Satellite Photographs, automatically when phone is answered. NEW CATALOG of low cost ,,,r I[P electronic parts. Send for FREE National -Local Weather Maps. How! Records both sides Learn $1.00. Atlantic of phone conversation.Each copy. ALL ELECTRONICS CORP., Dept. F, 905 Vermont Stops recorder 1 S. Sales, 3730 Nautilus Ave., Brooklyn, NY 11224. Phone: (212) when phone is hung up. 1 Ave., Los Angeles, CA 90006. 372-0349. ;, This device is not an answering service, $18.95 . " Oty Disc Aral 1 Super BUILD AND SAVE TELEPHONES, TELEVISION, DETEC- Powerful ,g .j y New Morse -A Word Code Reader TIVE, BROADCAST Electronics. We sell construction plans Wireless Mic . with an 10 times more Engineering Service. Speakerphones, Answering Ma- powerful than other mics. - I IDEAL FOR OEGINNERS. SWL'S AND chines, Transmits up to'4 mile to AMATEURS. CONNECTS TO YOUR Carphones, Phoneyision, Dialers, Color TV Convert- any FM radio. - ,,,e r,n.. RECEIVER SPEAKER. Easy to assemble kit. 15V battery (not incl.) FULL EIGHT ers, VTR, Games, $25 TV Camera, Electron Microscope, CHARACTER READOUT. ORDER Can (305) 725.1000 ca-NORL9'. Awn Sa6995. KIT Special Effects Generator, Time Base Corrector, Chrome or send 51e.95 01.00 shipping per ,,_ 5169.95 SEND Item to CHECK OR MONEY ORDER. USE USI Corp.. P.O. Box PE -2052, Melbourne, FL 32901. Key. Engineering Courses in Telephone, Integrated Circuits, YOUR VISA OR MASTER CHARGE COD'. accept. For catalog of transmitters. voice ADD 51.50 FOR Detective Electronics. PLUS MUCH MORE. NEW Super Hob- I scramblers SHIPPING. and other specialty items. enclose 52.00 to USI Corp. . by Catalog PLUS year's to ' e Jf. subscription Electronic News Let- .'. -7.77.77'-'-T4.'.7..".7.."-'..'R 'Corporatltin " Tel.: 414-241-8144. ter, $1.00. Don Britton Enterprises, 6200 Wilshire Blvd., Los P.O. Box 513 PE, Thlenssille, Wisconsin 53092 Angeles, Calif. 90048. EXQUISITE ELECTRONICS KITS for beginners and RF POWER TRANSISTORS - MRF 455A - $17.95, MRF NAME BRAND Test Equipment. Guaranteed discounts up to 454A- $24.95, pros. Free brochure. LOGICAL SYSTEMS, 3314 2N 5591 - $8.90, 2N 6084 - $14.50, more. 50%. Free catalog. Salen Electronics, Box 82, II 'H' Skokie, TV, audio, radio, VTR transistors, IC's, diodes, SG 613 60077. St., Vancouver, Washington - 98663. $5.90, STK 013 - $8.40, AN 239 - $4.90, more. Send for free catalog. B 8 D Enterprizes, P.O. Box 32, Mt. UNSCRAMBLE Jewett, PA CODED MESSAGES from Police, Fire 'TREMENDOUS 16740. (814) 837-6820. 24 hours. and Medical Channels. Same day service. Satisfac- BIIYS In New tion guaranteed. Don Nobles Electronics, Inc., Rt. 7, And Gov't Surplus Equipment Box 610, Hot Springs, Arkansas 71901. (501) Dial Telephone "SUPER 623-6027. 4411`..<0:? Save us the lobor costs of cleaning aro skle SnyS on UNSCRAMBLERS FOR any scanner. Several models srcial 5+ em. avail- relephorKs. Work on any commercial system. yttr °t`a y°t. O,p\e eOt able. Free literature. Capri u\ o\OJa tro°ayo' et9t Electronics, 8753T Windom, St. Complete. I no parts missing I in good o. Louis, MO 63114. working order Your choice of desk or wall stns / models These are tokeouls from commercial UNSCRAMBLERS, seven models available to decode police, service ( not toys I. Instructions furnished. OF yy Qe e° La t0\d5. ambulance, and fire coded de- transmissions. Other scanner e vices. Tone encoders/decoders. Telephone accessories, etc. CM, $7.9, e`6patey0oeot ::..:,,,P,.' F. .ii..,.,E..P.r teeGa Free Catalog. KRYSTAL KITS, Box 445, Bentonville, AR oJnte\ae5 Pty aa,O 72712. (501) 273-5340. FREE RIG °oJ CATALOG Show, 'lSAVINGS On ee ot0 e0 Otty JGeotretr° a eo\\ aQ `e,AA POLICE/FIRE SCANNERS, crystals, antennas, CBs, Radar .1. et 6 e tc ó o t' Detectors. HPR. Box 19224, Denver, CO 80219. . Q ty 9 POwe,tRy:,.' CHINK. SPRAYING T.ePAPLa MINT oT.H, teQt . °t` toQeayoV.e °Jty'QeQo to ao etg P0, aV-e CB RADIOS, VHF -UHF Scanners, Crystal, Antennas, Radar tiot \°J yClz Surplus Center Box 82209 -PE Lincóln, Ne. 68501 ^ Detectors. Wholesale. Southland, Box 3591, Baytown, TX \reo () 77520. °Ar SATELLITE TELEVISION - Build or buy your own earth sta- 5Q^ PRINTED CIRCUIT supplies, chemicals, tools, artwork, plat- tion. Article gives much hard to find, necessary information. ing solutions. Major credit cards. Send Catalog $2.00, refundable. $3.00. Satellite Television, R.D 3, Box 140, Oxford, NY TEST EQUIPMENT, new and used. Catalog $1.00. PTI, Box CIRCOI_EX, Box 198, Marcy, NY 13403. 13830. 8756, White Bear Lake, MN 55110.

116 POPULAR ELECTRONICS AmericanRadioHistory.Com DISCOUNT C.B., SCANNERS, ACCESSORIES, Free Cata- MODEL 33 TTY wiring fully explained with drawings. $3.00. TOP QUALITY SPEAKERS AND KITS. Send $1.00. Speaker log Crystals: CB. Ham, Scanner. All freqs. Same day service. Walker, 403A Whitaker Rd., New Market, TN 37820. Warehouse, 809 North Route 441, Hollywood, FL 33021. XTALS, Box 42-E, Prospect Hts., IL 60070. TELSA COIL - 40 SPARKS! Plans $7.50. Information 75 TRS-80 USERSw: We have hardware and software. Write for cents. Huntington Electronics, Box 2009-P, Huntington, Conn. current list. HARTMANN-LANG, Box 693, Chatham, NJ micro -madness 06484. 07928. An actual micro -computer chip NEGATIVE ion generator; build with easy -to -get parts for less enlarged 80x to become a tanta- with every order. All top quality mer- than kit prices! Complete plans $5.00. Lunatrix, Box 891 -PE, FREE CA3140 OpAmp x 14", lizing jigsaw puzzle. 10" Yucaipa, CA 92399. chandise. Send for bargain catalog. KEY ELECTRONICS, 252 pieces. Order yours now! Box Schenectady, NY 12303. 3506P. Send $10.00 ppd to: BUILD YOUR OWN desk and filing cabinet. Jig saw only tool ELECTRONIC CATALOG Free. Over 300 pages. Parts, sche- Eubanks Engineering, P.O. Box used. Plans $3.95. Feldar Products, Dept. Al, Box 7382, Sta. matics, etc. Everything needed by the hobbyist or technician. 127, Valencia, PA 111059. A, Saint John, N.B. E2L 4S7. U.S Inquiries. NY 11772. T & M Electronics, 472 East Main St., Patchogue, PROJECTION TV ... Convert your TV to project 7 Foot pic- (516) 289-2520. SKIPMASTER halts CB skip noise, bleedov=_r. Adjustable ture. Results equal to $2,500 projector. Total cost less than Matrix RECORDS - TAPES! Discounts to 73%. All labels; no pur- control, easy mounting for base, mobile. $24.95. Com- $20.00. PLANS & LENS $16.00. Illustrated info. FREE: Mac- chase obligations; newsletter; discount dividend certificates. munications, 611 Norwegian. Pottsville, PA 17901. (717) 622- rocomch, Washington Crossing, PA 18977. 3283. 100% guarantees. Free details. Discount Music Club, 650 ELECTRONIC KITS. Power supplies, function generators, Main St., Dept. 5-0580, New Rochelle, NY 10801. USE THOSE SALVAGED PARTS! Color and number code etc. Everything needed for your electronic workbench. Also for potentiometers, capacitors, transformers, resistors, kits. Free catalog. Estes Elec- UNUSUAL CB ITEMS. Modifications, books, repairs, range- charts audio and other experimenters page for easy reference - complete boosting accessories. Catalog S1. CB CITY, Box 1030PE, coils, more! Handy size tronics, Fit. 2, Box 170, Alexander City, AL 35010. set $2.00. Trip Engineering, Box 103, MIT Branch, Cam- Woodland Hills, CA 91365. Watt/ Channel Stereo Amplifier for $125, .3% bridge, MA 02139. BUILD 270 T -/D. Details: BHL, P.O. Box 2804CS, Pullman, WA 99163. [111 PRINTED CIRCUIT BOARDS. your artwork. Quick delivery. audioltitl4 PROJECT SCHEMATICS for the Junkbox ex- Reasonable. Atlas Circuits, Box 974, Waynesville, NC 28786. 999 SIMPLE MAKE ITI Tubes. Transistors, Chips. index Complete (704) 456-3739. perimenter. - Audiokit 62, 6 in/2 out pro mic m'xer parts and reference. Send $3.00 to: Electronics, 1700 S. perfect for live recording. Can be OSI CHALLENGER 1P - Superboard II. 90 page step-by- Union Rd., Manteca, CA 95336. assembled in just hours. Features step programming manual, $5.95 + $1.00 P&H. TIS, Box treble, bass, pan, cue, echo, gain STUDIO II Conversion to Microcomputer! Plans $5.00. Kits 921 -PE, Los Alamos, NM 87544. control on all inputs. Kit ... $265. available ARESCO, Box 1142, Columbia, MD 21045. (301) . . check or Assembled $395. Send 730-5186. money order to: Audiomarketing, 652 Rd., Stamford, CT 06906 1 Glenbrook MICROCOMPUTERS KIT BUILDERS DELIGHT - Full loudspeaker parts program, 11 or call us Toll Free at 800-243-2598. kits, plans, closeouts, $1.00 for complete catalog. C.C.L. En- POLICE SCANNERS - WHOLESALE PRICES. Over 25 TRS-80 PARALLEL I/O. PPI-80 contains three 8 -bit program- terprises, Inc., 30682 San Antonio, Hayward, CA 94544. models. Bearcat 300-$379.95. Regency M 100-$209.95. mable ports with switch selectable address decoding. Plugs BUILDING YOUR OWN SPEAKERS? Use dual transmission Bearcat 220 &250-$269.95. Same day shopping. VISA,MC: Into keyboard or E/I. PCB and manual $25.95. Quant Sys- lines. Build a dual transmission regenerator. Accepts dual (415) 573-1624. Free catalog. Write: Scanners Unlimited, tems, Dept. PE, Box 628. Charleston, SC 29402. transmission lines; Subwoofer connections; Drive multi- 1326 El Camino Real, Belmont, CA 94002. BASICS of Servomechanisms and Operational Amplifiers - speakers per cabinet; Three dimensional acoustic switch; Infi- GUARANTEED TEST EQUIPMENT. Surplus at surplus Clear text "instant breadboarding" result in solid understand- nite power handling; Controls impedance, balance, separa- prices. List $2.00 Refundable. Jack Watts Co., Box 25, Co- ing of fundamental concepts. Cassette for TF.S-80, Level II, tion, etc, Use with existing speakers too! Under $15.00 to rona, CA 91720. 16K. $9.95. Omni Systems Co., PO. Box 29347, Minneapo- build. Plans, send $6.00 to: D.T.R. SYSTEM, 1600 Woods lis- MN 55430. Road #D, Winston-Salem, NC 27106. SAVE 50%. Build your own speaker system. Write: McGee Radio Electronics, 1901 McGee Street, Kansas City, Missouri LASERS HANDBOOK with burning, cutting, Ruby Reds, CO's 64108. PLANS AND KITS complete plans, books, and parts. Send $4.00 to: Famco, Dept. PE, Box 1902, Rochester, NH 03867, CATALOG OF ELECTRONIC PLANS. Preamps, speakers, Patent No, FREE KIT Catalog contains Test and Experimenter's 4066953 crossovers, transmitters, linears and more. Catalog and Con- Equipment. Dage Scientific Instruments, Box struction Guide, S1.00. Peter Schmitt Enterprises, Dept. EP, CVP-Tester Milwaukee, 53207. P.O. Box 07071, WI A Pocket Multitester 1111 1054P, Livermore, CA 94550. You Can Test For: ALARMS Floating grounds Fuses Leakage Continuity AC -DC Voltage A Must for the: Búrglar Fire rPróie Lion Polarity Electrician Protect Your Life, Home, Business,,Auto, etc. Engineer oz Only Hobbyist TIGER 500 Our catalog shows how. Install your own alarm systems and devices and save ¡SSS. We Electrónic - SIM PLI-KIT $ 9 9 5 L{ offer FREE write-in engineering service. Technician Ie.n, Pdu,n1,11:, e, xigbauliry FOR THE DO-IT-YOURSELFER FREE CATALOG to: u.m s.n.m,.a o.d«, Send Check or Money Order NOW! a high quality CD ELECTRONIC ELECTRICAL INSULATION CO. IGNITION SYSTEM in kit form. Burdex Security Co. Box 82802 -PE Lincoln,Ne.68501 P.O. BOX 3919 SARASOTA .F LA. 3351 Contains all components and solder to build complete Solid -State Electronic CD POLICE DIALER $29.95. Free burglar alarm equipment cata- Ignition System for your car. Assembly log. Sasco, 5619P St. John, Kansas City, MO 64123. (816) TELEMETRY TRANSMITTER: Transmits BIOPHYSICAL requires less than 3 hours. 483-4612. to any ordinary FM radio. Transmit- your heart, (EKG), signal Increases MPG 15% Eliminates 4 or 5 tune-ups ted data consists of an audio tone which is frequency modu- Increases horsepower 15% Instant starting, any BURGLAR, FIRE, CAR! Finest equipment! Save! Catalog, lated by your EKG signal. The tone allows you to monitor your Plugs and Points last weather Decal, 50c, Refundable! AAS, 186A Oxmoor Road, B'ham, heart rate and hear EKG frequency components which other- 50,000 miles Dual system switch AL 35209. wise could not be heard. Built-in electrodes make it easy to 12 neg. Fits only volt ground... PERIMETER. Free Warning use. Completely assembled, battery included. Approximate ULTRASONIC- WIRELESS- Only $26.95 postpaid Decal with catalog EAC. Box 7881G. Colorado Springs, size: 4.4" x 2.4" x 1.2". Order Model BHT -14. $27.50. OMNI- -$1. CO 80933. TEK INC., P.O. Box 726, Loveland, CO 80537. 7 PStar Corporation P.O. Box 1727 Grand Juncuon, Colorado 81501 SECRET TELEVISION CHANNELS IN YOUR HOME without set modifications. Latest movies, sports, night club acts, reli- HIGH! FIDELITY gion, it's all in your neighborhood, but kept secret from most PRINTED CIRCUIT Boards from sketch or artwork. Kit pro- people. Complete detailed plans on how you can start receiv- jects. Free details. DANOCINTHS Inc., Box 261, Westland, DIAMOND NEEDLES and Stereo Cartridges at Discount ing these SECRET channels for $100.00 or less. Send $25.00 MI 48185. prices for Shure, Pickering, Stanton, Empire, Grado, Audio cash, check, or moneyorder ... or $4.50 for more information, Technica, Osawa, Satin and ADC. Send for free catalog. Noblesville, IN ELECTRONICS KITS: For information, send 500. GI Kits, Box to: TELE-TEC, Dept. SATT., 8688 Royal Drive, LYLE CARTRIDGES, Dept. P, Box 69, Kensington Station, 2329, Garland, TX 75041. 46060. Brooklyn, New York 11218. Toll Free 800-221-0906 9AM - TRS-80' COMPUTERS, LII-16K $680, Disk $415, Expansion HI Fl STEREO AMPLIFIER. Build your own, at half market 8PM except Sunday. price! Info $1.00. Otech, P.O. Box 1245, Des Plains, IL 60018. INT-16K $375. Order now, prices $2.00 refundable. Micro- AUDIO. VIDEO, ELECTRONIC PRODUCTS: Best Pricing, NC 28215. computer, 503D Riverfalis, Charlotte, SPEAKERPLANS- Build ANY size speakers without special Delivery! Personalized Service! SONY, DBX, Mobile Fidelity, Hewlett-Packard, BSR X-10, Multi -Track Equipment. WYCO HOW TO BUILD CROSSOVERS. Send S.A.S.E. for catalog tools, experience. FOOLPROOF, illustrated instructions, P.O. Box 887, Cary, NC 27511. 1-800-334-2483 of crossover information publications. Mesalab, Dept. PE, parts sources. 80% SAVINGS! Rush $4. SPEAKERPLANS, SALES. 3942 Mesa Avenue, Sarasota, FL 33583. 334 Pursel, Phillipsburg, NJ 08865. (N.C. 919-467-8113). DUAL Trace 15mhz Heathkit Scope. Xlnt Cond. $375. 68 No. NEW-UNSCRAMBLER PLANS. State of art integrated circuit Hill, Pasadena, CA 91106- (213) 795-7453. design. Fits all scanners. Complete plans, $3.95. Innovative WANTED Marketing, Box 7577, Huntington, WV 25777. KEYBOARDS for synthesizers and organs. Completely as- wanted. Highest sembled with single/or dual contacts. Send for information: FIBER OPTIC EXPERIMENTER'S KIT. Includes fiber, cable, GOLD, Silver, Platinum, Mercury, Tantalum Mercury DEVTRONIX Organs, Dept. 71, 6101 Warehouse Way, Sac- tools and instructions. Send $6.00 to: FIBERTRONICS, Box prices paid by refinery. Ores assayed. Free circular. ramento, CA 95826. 322, Primos, PA 19018. Terminal, Norwood, MA 02062. 117 MAY 1980

AmericanRadioHistory.Com WANTED. RADIATION MONITOR ASSEMBLED. Write: G. UNIVERSITY DEGREES BY MAIL! Bachelors, Mas- DIGITAL WATCH REPAIR - Learn to repair digital watches Miller, Box 14366, Austin, TX 78761. provide service to jewelry and department stores part Ph.D's. - - ters, Free revealing details. Counseling, Box time or full time. We supply training - equipment - replace- 317-PE05, Tustin, California 92680. ment parts. Zantech, Inc., 13 Greentree Rd., Trenton, NJ TELEPHONES & PARTS 08619, (606) 586-5088. LEARN WHILE ASLEEP! HYPNOTIZE! Astonishing details, strange catalog free! Autosuggestion, Box 24-ZD, Olympia, ENERGY DRIVE SYSTEM that provides energy. Montgom- TELEPHONES UNLIMITED, EQUIPMENT SUPPLIES, Washington 98507. ery, 4255 Farlin, St. Louis, MO 63115.

ALL TYPES. REGULAR, KEYED, MODULAR. Catalog RADIO BROADCASTING: Become DJ, engineer. Start your ION GENERATION & STATIC MEASURING DEVICES prod- call (714) 563-5555 or mail $1.00 refundable. Box own station - investment/experience unnecessary! Receive uct line for sale - reasonable terms. Business Brokerage free equipment, records. Free details. Broadcasting. Box Group, 57 North Street, Danbury, CT 06810. 1147E, San Diego, CA 92112. 130-A5, Paradise, CA 95969. $625/WEEKLY! Home mailing program. Free postage-sup- LEARN ELECTRONIC ORGAN SERVICING at home. Com- plies- $20 bonus! Write immediately. Treasure -7Y, Morrison, HOBBIES pletely revised course covers latest models including digital, CO 80465. LSI's, synthesizers. etc. NILES BRYANT SCHOOL, PO Box 20153, Sacramento, CA 95820. GREAT OUTDOOR FUN. EMPLOYMENT OPPORTUNITIES COLLEGE DEGREES BY MAIL! No classes. Fast. Economi-

SEARCH FOR . . silver ELECTRONICALLY gold. cal, Accredited. FREE Revealing details. Success, Box coins and relics with Whites Electronics mineral/ ELECTRONICS AVIONICS EMPLOYMENT OPPORTUNI- metal Pays for U.S. 13151-R5, Columbus, Ohio 43213. detectors. itself. Patented. TIES. Report on jobs now open. Details FREE. Aviation Em- For your nearest dealer r- HAMS: ADVANCED CLASS TEST GUIDE! Accurate! Send ployment Information Service, Box 240E, Northport, New and free catalog CALL TOLL FREE $11.50 to Dick Bash KL7IHP, Box 4325, San Leandro, CA York 11768. 1-800-547-6911 94579. INSTANT CASH COMMISSIONS Full or part time. Free AVIONICS Aircraft Electronics. Accredited School. Excellent Whites Electronics. Inc. PE -0 Dept. Employment Opportunities. Aero Technicians, P.O. Box 7PE, sales kit features America's largest line low-priced sewurrinlrSweet Home. OR 97386 Rexburg, ID 83440. Business, Printing, Advertising Specialties, Signs, NEW 1980 LEATHERCRAFT CATALOG! 100 pages of ove Calendars and other necessities used daily by 2100 genuine leather kits, tools, supplies. Easy way to make FOR INVENTORS business people. Profitable order. No extra money in your spare time, Send 500 for postage and repeat experi- handling to: Tandy Leather Company, P.O. Box 791, Dept. PATENT AND DEVELOP Your invention. Registered Patent ence. No investment. No collections or deliveries. PEC-5, Fort Worth, TX 76101. Agent and Licensed Professional Engineer, Send for FREE Write today. National Press, Dept. 05T, North Chi- PATENT INFORMATION every inventor should have. Rich- cago, IL 60064. TUBES ard L. Miller, P.E., 3612 Woolworth Building, New York, NY 10007. (212) 267.5252. ELECTRONIC ENGINEERING and TECHNICIAN EMPLOY- MENT Information for ANYWHERE in the U.S. FREE details. RADIO & T.V. Tubes- 49 cents each- Send for free Catalog. Write: NATIONAL ELECTRONIC EMPLOYMENT SER- Cornell, 4213 University. San Diego, Calif. 92105. INVENTIONS WANTED VICES, Box 14766, Austin TX 78761. TUBES: "Oldies", Latest. Supplies, components, schematics. FREE CONSULTATION NO IDEA TOO SMALL ELECTRONIC TECHNICIANS: $23,000 or more per year to Catalog Free appreciated). 7519 -PE Ma- (stamp Steinmetz. Disclosure registration Potential cash or royalties from manulaeturers seeking new start! Minimum experience. No degree. Jobs throughout U.S. plewood, Hammond, Ind. 46324. ideas For tree information on 5dw lo register your ideas. Call or write Free report. TJM. Dept. B, Box" 254490, Sacramento, CA 95826. TUBES -RECEIVING, Industrial and Semiconductors Factory AMERICAN INVENTORS CORP. Boxed. Free price sheet including TV, Radio and audio parts HOW TO an new 59 Interstate Dr. Dept PE START exciting career. Average computer list. Transleteronic, Inc.. 1365 39th St., Brooklyn, New York west Springfield, MA 01059 (413) 737-5376 programmer makes S20,200. Wide open opportunities for 11218. Telephone: (212) 633.2800. Toll free: 800-221-5802. d Fee Based Serwa Comraey computer programmers, operators, technicians. Free training available. Guidebook shows where, how to start a new future. $3.00. Carol) Associates, 33402A Nottingham, Dana Point, GOVERNMENT SURPLUS NEW! "Patenting Your Invention Yourself!", $29.95. Regis- tered Patent Attorney, 7400 ZD Benjamin Franklin Sta., CA 92629. Washington, DC 20044. MANUALS for Govt Surplus radios, test sets, scopes. List $1.00 (cash). Books, 7218 Roanne Drive, Washington, D.C. INVENTORS Patent your invention. Free initial consultation. SITUATIONS WANTED 20021. We are registered by the U.S. Government. VICTOR J. EV- ANS & CO., 4637 Eastern Ave. N.E., Washington, DC 20018. QUALIFIED ELECTRONIC TECHNOLOGIST will work cheap SURPLUS JEEPS- $19.30!1- CARS -$13.501 - 650,000 Since 1898. ITEMS!! - GOVERNMENT SURPLUS!! - Most COMPRE- for employer/sponsor to the U.S.A. Box 163, Station T, Toron- HENSIVE DIRECTORY AVAILABLE tells how, where to buy!! CHEAP PROTECTION for your ideas. Inventor's Logbook. to, M6B 4A1, Canada. - YOUR AREA - $2. - MONEYBACK GUARANTEE!! - Verification format, permanent binding; moneyback guaran- "Government Information Services", Department GE -21, Box tee. $14.95. JorJan. Box 405PE, Ellensburg, WA 98926. 99249, San Francisco, California 94109. DO-IT-YOURSELF JEEPS ... $18.88!! ... 675,000 Items! Buy In Your Area! BUSINESS OPPORTUNITIES AUDIO/ANALOG/SYNTHESIS. Plans, parts, kits, etc. for the How! Where! "Moneyback GUARANTEED 1980 Govern- - most exciting sound projects ever. Get on our mailing list, ment SURPLUS Directory" Including: "Buy G -Lands,' I MADE $40,000.00 Year Mailorder! - - by Helped others make send 25c to: CFR Associates Inc., Newton, N.H. 03858. "G-OillG-Gas LOTTERIES," - $2.00. GSURPLUS, Box money! Details 25c. Torrey, Box 318 -NN, Ypsilanti, Michigan 2009-N, Syracuse, NY 13220. 48197. 125 WAYS TO IMPROVE YOUR GAS MILEAGE! Latest tips & techniques on how to increase gas mileage 15% to 35%. FREE CATALOGS. Repair air conditioning, refrigeration. Instructions $9.95 -Money Back Guarantee. Fuel Expanders, Tools, supplies, full PERSONALS instructions. Doolin, 2016 Canton, Dallas, P.O. Box 17711, Irvine, CA 92715. Texas 75201. SAVE MONEY on costly CB and car radio repairs. Correct MAKE FRIENDS through corre- NEW LUXURY WORLDWIDE international CAR WITHOUT COST! Free Report. Co- many problems yourself. Instructional booklet $2.00 postpaid. spondence, illustrated brochure free. Hermes-Verlag, Box Box 6073, Toledo, Ohio 43614. (419) dex-ZZ, 865-5657. Midwest Sound Service, 10510A Grandview Road, Kansas 110660Z, D-1000 Berlin 11, W. Germany. MECHANICALLY INCLINED individuals desiring ownership City, MO 64137. MAILORDER SUCCESS! Interested? Free exposé. TWP-V, of Small Electronics Manufacturing Business - without in- Box 6226, Toledo, Ohio 43614. vestment. Write: BUSINESSES, 92-K2 Brighton 11th, Brook- lyn, New York 11235. REAL ESTATE LOFTINESS MUSIC? Connoisseur's recommendations -$2 Box 5600, Jacksonville, FL 32207. MILLIONS in Mail!!! Free Secrets. Transworid-17, Box 6226, Over 2,700 top val- Toledo, OH 43614. BIG ... FREE ... SUMMER CATALOG! PENFRIENDS - ENGLAND - USA, through correspon- ues coast to coast!! UNITED FARM AGENCY, 612 -EP, West dence. Send age, interests. Free reply. Harmony, Box IPE, 47th, Kansas City, MO 64112. Brooklyn, New York 11223. MECHANICALLY INCLINEDINDIVIDUALS Assemble electronic devices in your home. RUBBER STAMPS INSTRUCTION Knowledge, or experience not necessary. Get started in spare time. Above average profits. $300 - RUBBER BUSINESS Many new prod- $600 Wk possible. Sales handled by others. No in- STAMPS, CARDS. ucts. Catalog. Jackson's, E-100, Brownsville Rd., Mt. Vernon, for free vestment- Write details. III. 62864.

PASS, FCC EXA ELECTRONIC DEVELOPMENT LAB - Box 1560PE, Pinellas Park, FL 33565 Tye Original FCC Tests -Answers exam manual that BOOKS AND MAGAZINES prepares you al none for FCC First and Second class Radiotelephone licenses. Newly revised muaiplc-choice ERASE DEBTS with little-known law-create wealth!! Details exams cover all areas tested on the actual FCC exam. ELECTRONIC MUSIC and home recording in Polyphony Plus "Sell-Study Ability Test." Proven! $9.95 FREE Blueprints, No. EE5, Box 100, LaGrangeville, NY - magazine. projects, com- postpaid. Moneyback Guarantee. 12540. Advanced applications, interviews, puter music. Sample $1.50. Subscription (6 issues). $8.00 ox P CORIInAND PRODUCTIONS BIG MONEY! Interested? Free disclosure. Febre-V, Box US/$10.00 foreign. POLYPHONY, Box P20305, Okla. City, Rad,o Erginegyng (»vrslon 9. San Francisco,, ¿A 94126 6073. Toledo, Ohio 43614. (419) 865-5657. OK 73156.

MEDICAL ELECTRONICS TECHNOLOGY, home study. FREE Inflation -Beater Book "2042 Unique, Proven Enter- COMPUTER PROGRAMMING. Informative booklet: Re- Troubleshoot medical instruments. University Reme 5, Box prises." Fabulous "Little Knowns." Work home! Haylings.-S, quired aptitudes, education; how, where to train; etc. $4.98 9622, Fresno, CA 93793. Carlsbad, CA 92008. postpaid. Routh, 256 N. Craig, Pittsburgh, PA 15213. 118 POPULAR ELECTRONICS

AmericanRadioHistory.Com , _. t ó L4 rf a, tv NC9 d780p C "mHz irace ' Rp9s 35r0;0136CSopPe Hickok 15 MHz Triggered ( RHickokg.95 21./59 Dal al00/869.00H 100 Reg. 565.00/399.00 Trace >>49 9s359 - /W .i_- ace,l 4517 1[frtCll

Hickok Function Generator Id I 1 (: U Reg. 225.00/ 169.95 s , a e .:d Mode Hickok Model LX303 `11A-1 ` 30pL99.9$CD ter nModel310. Meter 66.95 ,. 129.95 Mod ta 1711, Elect. Soldering 111, Weller CSC. Log fp Probe LP -1 39.gá Statio125.00/99/ 99.95 609 5.00 EC1000 , Cariagga Reg- 99 95/'15.95 ..... Master Weller Xcelite Service lffC!_ SC 300 Model 99SM 39.95 Platt r 99PR 15.95 CSCMI00MHz oesca/erC Reg. Case Roll Kit Model 8"I9.95/59.95 S all B&K Scope 1432P CS C kX 0 er Ma n/ iát4111l1li, 15 MHz Dual Trace 530ún1 r Caca/ " Reg. 840.00/[9a4 - H1Ck0onaoeto 1,11133,501:. Som ° Ca// 35.00/1i9- Re9 Frequency counters, oscilloscopes, signal generators, multimeters, tools, and probes Communications are among hundreds of products available. Large inventory of Tektronix, Hewlett-Pack- Technology ard, General Radio, Fluke, and Boonton available with replacement parts as well. Master rr uc,'ncarpara'ea Charge - Visa Cards accepted. Come in, call or write for free brochures 9AM - 9PM Mon- 448 Merrick Road, Oceanside, N. Y. 11572 U.S.A. (516) 536-5724 day through Friday. Export Inquiries invited. Communications for Worldwide Use Telex 640-488/TWX 510-225-7536

CIRCLE NO. 10 ON FREE INFORMATION CARD

VIDEO SOURCE BOOK - Your guide to 15,000 prerecorded MPG INCREASED! Bypass Pollution Devices easily. RE- VERSIBLY!! video programs - 700 pages - easy -to -use, $19.95. Money - Free details - Posco GEES, Box 300, La- back guarantee. Check or money order to: NVC, P.O. Box 3, Grangeville, NY 12540. BEAT HIGH CAS PRICES! Dept. 1OPE, Syosset, NY 11791. Master Charge and VISA GAS GADGETS DO THEY WORK OR NOT? Which ones do only CALL NOW TOLL -FREE, 800-824-7888, Calif. 800-852- as advertised, which ones are RIP-OFFS. Receive your copy 7777, ask for op. 909. "GASAVERS NEWSLETTER" before you buy one. Plus 1 INFLATION AND RECESSION ARE HERE. Learn how to fi- product evaluations on those that work. Send $2.00. Fuelex- 1 nancially protect your family. "Gain Control of Your Money" - panders, P.O. Box 17711, Irvine, CA 92715. 1 a new manual that shows how to analyze finances and gain PROTECT YOUR AUTOMOBILE FROM THEFT! Free Infor- power over inflation. Moneyback guarantee. $4.95 to East En- 1 mation. Fleming Sales, 3304 Tanterra Circle, Dept. PE5, 1 terprises, Dept. El, 10030 N. Blaney, Cupertino, CA 95014. Brookevelle, MD 20729. 1 INSTANT MEMORY ... NEW WAY TO REMEMBER, No CORVAIR PARTS 290 page, 4500 item catalog rushed. Memorization. Release your PHOTOGRAPHIC Memory. - 1 Clark's Corvair Parts, Inc., Shelburne, Mass 01370. 1 Stop forgetting! Free information. Institute of Advanced Think- ing, 845PP ViaLapaz, Pacific Palisades, CA 90272. GASOLINE MILEAGE INCREASED DRAMATICALLY, easily!! Details FREE!! Techneering, Box 12191ZD, Norfolk, VA 23502. 1 1 MOTION PICTURE/VIDEO FILMS 1 I °1980 Electronic Experimenter's Handbook CELEBRATE W.C. FIELDS 100th Birthday! Order his 16mm 1 1 B&W 400' Snd Film "Much Ado About Golf." Low priced C 9BOELECTR& Electrify Your Bike! $29.95 ea (40. list), or "Bank or "Never Tell A each EX EMKER'S, This a Dick" Lie", N latest edition includes Micro 1 800' 16mm B&W Snd film, $69.95 ea ($80. reg), add $3. per r,":=7"`=.2.11"" computer Buying Section in addition 1 PEDALPOWER exciting new bike drive tames tough reel for ship. Price changes next month. Castle Travel Films, -~.:11."7.,-.1to a host of exciting construction 1 Be when you want. Fits all 200' Color Mag Snd $19.95 ea ($32.95 list) "San Juan" or ijaranra"=,^"^ projects with complete construction 1 hills. independent. Shop "New York", or Ali-Spinks I, boxing upset of century. 4 reels plans, parts lists, and printed cir Bikes, Adult Trikes. Installs in minutes. Thousands 1 S-8 Color/Snd, complete 64" version, only $150. PPD. (you y,4 cuit board patterns. PLUS -A Com- 1 sold. Recharges overnite. Travels 100 miles for a save $75.). "Who's On First" Abbott & Costello 100' S-8 BIW N: puter Buying Directory with product dime. Get your exercise without strain. Pedal easily Snd Baseball comedy only $12.95 PPD, 200' S-8 Snd $29. y,: .", specifications, latest prices, and with motor engaged to help improve your health. 1 "Black Sunday" Super Bowl crowd endangered; 400' Para- °'' photos. Only $2.50! Visit friends. Travel to work or ride for fun. Starts mount Feature S-8 color snd $64.95 + $2. ship (you save 1 Order from ELECTRONIC EXPERIMENTER'S HAND- without pedaling. Noiseless, nonpolluting. Virtually 1 $5.). Another May special, complete set 16mm B&W snd BOOK, Dept. 01237, P.O. Box 278, Pratt Station, 1 maintenancefree operation! News Parades covering the tumultuous 60's. 400' film, set of Brooklyn, NY 11205. Enclose $3" ($2.50 plus postage 1 10-'60-'69, $397.50 PPD. Sold in sets only real news for - and handling). Outside U.S.A. $4. 1 collectors. Video Cassette special, expires 5/20'79 World Se- 1 ries Video Movies (Pittsburgh Baltimore), hilites of all 7 games 'Residents of CA, CO, DC, FL, IL, MI, MO, NY 1 CALL TOLL FREE and VT add applicable sales tax. only $69.95 ea (reg $74.95) + $2. ship. Indicate Beta or VHS, STATE 800-257-7955* 1 Charge your films & tapes to MasterCharge & Visa. III res. + 1 6% tax. Hollywood Gold Video movie cat., $1.50; Univ. S-8 1 For Free Booklet and Special Offer or write: film cat. $1.25; Columbia film cat. $1.25; Columbia VTR cat. 1 75; Paramount features 400; asst brochures, Sportlite, Ring toda« CASSETTES General Engines Co. I Classics, Cloud 9, 40c ea. SPORTLITE FILMS, Elect -5, Box 5706 Mantua Blvd. Sewell, NJ 08080 24-500, Speedway, IN 46224. PSYCHOLOGY TODAY offers a free catalog which 1 includes a complete up-to-date listing of cassettes available. These tapes feature leading authorities In AK, HI. NJ call collect (609) 468-0270 I who share their ideas and findings on a wide range 1 MISCELLANEOUS of important topics in all areas of the behavioral and 1 social sciences. 1 To obtain the Psychology Today Cassette catalog, FREE Hypnotism. Self -Hypnosis. Sleep Learning Catalog! MeALPOWR FREE -OF -CHARGE, write to: CASSETTE CATALOG, 1 I Drawer H400, Ruidoso, New Mexico 88345. P.O. Boo 278, Pratt Station. Brooklyn, N.Y. 11205..,

CIRCLE NO. 26 ON FREE INFORMATION CARD AmericanRadioHistory.Com ELECTRO IBS oice=.x)Personal Electronics News

STARTLING' ACCEPTANCE OF COMPUTERS is projected by a University of California Office of Interdisciplinary Programs study. By 1990, 40 -million personal computers, enough to put one in over 50% of U.S. homes, will have been sold to first-time users, and no major technological breakthroughs are needed to make the projection a reality. The study found the majority of current owners to be male, aged 20 to 45, middle class, and well educated, with 7 out of 10 having at least a B.A. degree. Their educational background is most often engineering, business, natural science, or mathematics, but many are self-taught on computers. It was found that 80% used computers at work or work closely with someone who does. Main uses for personal computers ale for video games, board games, and text editing.

JAPANESE FIRM ENTERS U.S. COMPUTER RETAIL MARKET. Super Brain, Inc. which has retail stores in Tokyo and Osaka, will offer a wide range of personal and business microcomputers as well as a complete line of peripherals. Los Angeles was selected for the company's first retail outlet location.

NEW ALPHANUMERIC DISPLAY forms numbers,upper- and lower-case letters, and scientific symbols using nested arrays of 23 dots or less as compared to typical 35 -dot displays. Called the Laitram system, the dots are tilted at a 60° angle to form the characters with a minimum of lights. The format can be multiplexed on a 5X5 matrix and extended raw formats can be used for dynamic scrolling to display entire messages. For specialized displays, arrays may contain the least number of elements to do the required job. Licensing to use the system is available from Laitram, Box 50699, New Orleans, LA 70150 (504-733-6000).

AN AUDIO RECORDING WORKSHOP will be held in conjunction with this summer's Aspen (Colorado) Music FestivaL The Aspen Audio -Recording Institute workshop will be offered three times during the summer (June 23 -July 13, July 14 -August 3, and August 4-24) and will have a maximum of ten students per session. Combining hands-on experience with lectures, classes are conducted by professional recording-industry representatives. The various music events at the Aspen Festival provide a range of opportunities on which to practice recording techniques. For more information, call 212-581-2196.

NOM E VCR SALES UP 73.4% over last year for the month ofJa.nuary reports the Electronic Industries Association, Total video cassette recorder sales to retailers were 40,443 units, compared to 23,330 for 1979. Total U.S. market for color TV receivers also increased from 622,111 to 636,316 for the month.

THE Uh ITED STATES ROBOTICS SOCIETY announces a major reorganization and expansion plan in response to increasing demands for information. The first step is the transfer ofUSRS' primary communications function from the Rio Grande Valley to Silicon Valley. Commitment has also been made to expand membership, staff, and activity to recognize the widespread conviction that robots and artificial intelligence will have a significant place in our society. Correspondence should be sent to USES, 616 University Ave., Palo Alto, CA 94301.

TWELVE HOURS RECORDING DNA CASSETTE can be achieved on Norwood's XLP4 system. By recording on all four tracks (two sides of tape) of a C-90 cassette, for instance, at a speed less than 1/2 in./s, the XLP4 24 -hour, 2 -speed player/recorder can records. complete book of up to 250,000 words. The two -speed electronic system plays and records at normal speed as well. Norwood Industries has recorded and released over 85 novels, book classics, radio shows and religious selections. The audio "Novels -on -Tape" library is said to be expanding at a rate of five titles per week.

120 POPULAR ELECTRONICS

AmericanRadioHistory.Com COBRA'S PUNCH-THROUGH SOUND COMES TO ° STEREO. The same technology that brought 1 a cif -alit-7 of sound toCB never before I. thc-t_ght-pclo,Rible, now brings a quality of sound to car stereo never before heard e Introducing Cobra's Punch- Tariugn Sound. AM/FM Stereo sound. 8 -track or cassette sound. Big, booming sound that gives yDu great highs and low-down -, lows. Because whichever , - Cobra receiver you -111:01 - choose, you get a - full 25 watts of " power plus an FM sensitivity _ of 1.9 microvolts. And when you match receiver to any one of Cobras's 11,j 2 -way or 3 -way speakers you get a , sound that really sings. Add a Cobra graphic equalizer/amplifier and boost , a yDur ewer output to 60 watts. And get so...indyou can feel. e your Cobra radio dealer today. And when you buy á Cobra you also get. a one -Tear warranty and the assurance that t1 -.re's a national network of factory vice centers to help you with installa- txn, service and advice. Because whether it's CB or kutos:Dund, if it comes from Cobra you lciow it's going to sound great.obra wt. Music Loud and Clear. obra Communications Products

- I DYNASCAN CORPORATION 6460 W Cortland St., Chicago, Illinois 60635 Write for color brochure.

CI 1CLE NO. 700N FREE INFORMATION CARD

- = - - AmericanRadioHistory.Com .. - . rl' .' ap i. - ti a I.'.'

;

' . /f . _:' '\\\\\\\\\\\\\\\\\\\\\\\ 1111111111111111\\\\\\ l\\It _.....' \ .-`... _; 1'''*1,- `, r^ 1 ^ l ' , `` 1 ¡! ' Y' \ \ 1 . 1 \ ` í , 1\ J I i The only computer with color, aT ?S 32 30 801 sound, user programmability and expandability al $599. A built-in, dual -track cassette taoe is also expanoable. Just add our deck with 1500 baud rate, for APF's "Building Block", an - digitally optional, four zo ti recorced,"saturated;' port expansion device, and you tape programs. A built-in sound can hook up c printer, telephone EL synthesizer. And two, built-in, modem, and additional memory `r game style °arke controllers, with cartridge or m ni -floppy disk drive. joysticks and numeric keypads. The Imagination For the name of your nearest Machine offers When you Imagination more at its price than any other want to go beyond Machine dealer call, APF's library of TOLL FREE: personal computer on the market educational, home - 1-800-223-1264. (New today. and -personal management or York residents call: (212) 758-7550) entertainment programs... when or write: APF Electronics, Inc. 444 Consider these features: 9K RAM, you want to create your own pro- Madison Avenue, N.Y., N.Y. 10022. with 14K BASIC in ROM,53-key grams... you can. The Imagination typewriter keyboard. A fine resolu- Machine is tion programmable in S599. Manufacturer's suggested retail price. picture, generated on your BASIC and 6800 machine lan- television set or monitor in 8 colors! guage. The Imagination Machine MPFeiectronics inc. "YOUR LIFE WILL NEVER BE THE SAME:' CIRCLE NO. 5ON FREE INFORMATION CARD

AmericanRadioHistory.Com