Rad ioEIectroni for your workbench build DIGITAL CAPACITANCE METER has 4 -digit LED readout decipher secret messages COMPUTER CRYPTOGRAPHY use your microcomputer build scope add -on TII`nr CvNurilFSIZEÏi;,,s!l;it for 3D patterns galore easy to build CB SWITCHER for music between CB calls . . . .-.. construction tqchnigu` :- ICBRICKLAYINC for miniature projects .1%.1-401,1s

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! . - 93çM%e rStereo Hobby C ner 400 rN ldA

M Zi 39V1H9S1)116M Jack Darr's Service Clin tiZ7Z9' at 95W00e S10 atrr v Hi-Fi Testleports

www.americanradiohistory.com new design... new features...unique, time-tested principle!

Weller controlled output soldering station

Model WTCPN. New convenience -features. Striking contemporary appearance. Completely new design. Now more than ever in a class by itself. Only Weller's advanced engineering could have improved on its own predecessor WTCPL Station, popular standard of the electronics industry. new heat shield for cool operator comfort new plug -in iron design for zero down -time new integral tip- storage tray new larger sponge for easier tip cleaning improved, unitized rocker switch and neon indicator light new impact- resistant case And add to these new features Weller's unique, proven, closed -loop, low- voltage circuit, with its "interchangeable brains" in the tip ... a ferromagnetic sensor that controls the temperature at 600, 700, or 800° F., protecting sensitive workpieces. To change temperatures, simply change tips with knurled thumb- screw. More than 50 options in configuration, tip size, reach, and temperature! Exclusive -process triple -plating prevents tip oxidation and "freezing ". With all these new features and exclusive principles, Model WTCPN is still all function ... no frills! It's UL- listed and OSHA -compliant, of course. And now it's available at leading electronic distributors ... coast -to- coast. See it there. For technical information, write on your letterhead.

, . ,, . ,,, . SOL (APO.

Weller - Xcelite Electronics Division

COOPER The Cooper Group INDUSTRIES P O BOX 728 APEX. NORTH CAROLINA 27502

CIRCLE 1 ON FREE INFORMATION CARD

www.americanradiohistory.com ANNOUNCING NEW LOW PRICES AT RADIO SHACK, THE "PARTS PLACE" i Top quality devices, fully functional, carefully inspected. Guaranteed manufacturer's quality control procedures. These are not rejet I; Tot to meet all specifications, both electrically and mechanically. All are fallouts, not seconds. In fact, there are none better on the n E wet! made by well known American manufacturers, and all have to pass Count on Radio Shack for the finest quality parts.

TTL Microcomputer Chip Digital 8080A Microprocessor. With a 16 -bit address bus capable of ICs addressing up to 65k bytes of memory and up to 256 I/O ports. "TRI- State" data bus gives it DMA and multiprocessing capa- First Quality Devices Made by bility. All National Semiconductor and Motorola buses TTL compatible. Up to 244 variable length instructions, with 6 general purpose registers plus an accumu- Cal Las, NOW lator. 40-pin DIP. 100% Prime. 276 -2510 17.95 Type No Yea, ONLY RS2102 Static RAM. 1024 -word by one bit random access read 7400 276-1801 S 49 35C /write 7402 276-1811 S 49 39C memory. Under 750 nS access. Single +5V power supply. 7404 2761802 S 59 35c 276 -2501 2 49 each or 8/14.95 7406 276-1821 S 69 490 1795 7410 276 1807 S 49 39c 7413 276-1815 SI 19 790 LEDs /Optoelectronics 7420 2761809 S 49 39C Digital Displays Cat. i_a -.1 NOW 7427 276 1823 S 69 49c Digits Size Drive No "ear ONLY 7432 276 1824 S 69 49C 744' 276-1804 51 59 990 X 4 0.5" Anod. 276 -1201 59 95 6.95 7447 2761805 S1 99 99C 01 LE 4 0.5" Cath 276 -1202 99 95 6.95 7448 276.1816 Si 99 99C 7451 276-1825 S 49 390 a 7472 276-1803 S 79 49c 7474 276-1818 S 79 49C Item Cat No. Reg. Now Only L:'I NOW 7475 276-1806 Si 19 790 Digits Size Drive Cat. No. 5 Solar Cell 276 -115 1.59 Ve.r ONLY 7476 276-1813 S 79 590 Silicon Solar Cell 276 -128 1.99 7485 276-1826 S 1 59 1.19 E 1 0.6" Anod. 276 -056 $3 39 2.99 E Photocell 276 -116 990 7486 2761827 S 69 49e EJ 1 0.6" Cath. 276 -066 $3.39 2.99 .5 FPT 100 19 276 -130 79C 7490 276-1808 S1 790 ô © 1 0.3" Anod. 276-053 $2.39 1.99 19 Lg Red LED 276-041 2/69c 2/490 7492 2761819 Si 69C © 1 0.3" Cath. 276-062 12 15 1.99 F Lg Clr LED 276 -047 2/69c 2/490 74123 2761817 Si 69 99C © 1 0.3" Anod. 276 -1210 4/66 17 .116.99 Med Red LED 276-026 2/69c 2/490 74145 2761828 Si 49 1.19 1 0.3" Cath. 276 -1211 4/04 17 4/6.99 74157 276-1829 SI 79 1.39 Med Ci, LED 276-040 2/69c 2/490 Red LED 74151 276-1834 S1 79 1.29 276-042 2/690 2/490 74 192 276-1831 SI 69 1.19 74193 276. 1820 S7 69 1.19 74194 276-1832 51 69 1.19 Project Accessories Diodes .4196 276-1833 51 69 1.29 Selected Last Now 74C and 4000 Series CMOS ICs Type Cat NO Vear Only 74C00 276-2301 S 69 490 164001 74CO2 276-2302 S 69 490 276 -1101 2/390 74C04 276-2303 S 69 490 154003 276 -1102 2/59c 2/490 '4, .,- 276-2305 5 69 490 154004 276 -1103 2 /69e 2/590 276.2310 S129 890 154005 276 -1104 2/79c 2/690 276-2112 5159 690 194735 276 -561 2/890 52 29 1.49 194739 276 -562 21890 52 49 1.69 194742 276 -563 2/89C 52 49 1.69 194744 276-564 2/890 4, iVi S 69 49C Trigger 4011 S 09 490 Diode 276 -1050 $ 49 390 4013 11t 51 29 890 4017 52 49 1.49 195401 276-1141 2/690 4020 52 49 1.49 195402 276 -1142 2/89c 2/790 X IC Troubleshooting Test Clip. Test up to 4027 51 29 890 165403 276 -1143 2/990 2/894 4049 .449 5 99 690 14 pins with probes or clips. Reg. 4.59 165404 276 -1144 2/S1.19 21990 4050 270-,450 $ 99 69C 276 -1950 Sale 2.99 PTC205 276 -1114 3/1.390 4511 276-2447 52 69 1.69 X IC Troubleshooting Test Clip. Test up to ¿SIR _70_24,, 5249 1á9 16 pins with probes or clips. Reg 4 99 SCR's and Triacs 276 -1951 Sale 3.49 Last Now Device Rating Cat No c Experimenter Socket. 2,07 rows of 5 Vear Only

connected tie 276-172. . 9.95 Linear ICs points LASCR 200V. 1 6A 276.1095 51 59 99C r ai Bus Strip. 2x40 connected tie SCR 39 89e First Devices by s points 2005.69 276.1067 SI Quality Clips to socket above 276 -173 1.99 SCR 400V. 6A 276 -1020 $1 49 99e

National Semiconductor 1 J ì 0 6 Standard Edge -Card Board. 22 -pin. Tnac 200V.66 276-1001 S1 39 89C and Motorola J U 1295 mounting holes 276 -152 2.99 E Tnac 4005.6A 276.1000 S1 49 990

s 2- Voltage Source Edge -Card Board. OR 50P15 1 4g 276-1151 79e Cat Last NOW 100PIV, 1 40 No Year ONLY 1368 mounting hales. 276-154 2.99 BR 276 -1152 994 3- Voltage Source Edge -Card Board. BR 1005.45 2761171 1.49 301AH 276 -017 $ 69 49e BR 200V. 4A 276-1172 1.69 1368 mounting holes 276-153 2.99 324N 276-1711 $1.99 1.49 BR 400V.4A 276 -1173 1.89 TO 22-Pin Edge -Card Board 339N 276 -1712 $1 99 1.49 Cernedor. BR 50PIV.6A 276 -1180 1.99 386CN 276-1731 $1 99 990 44- terminals 276 -1551 2.99 555CN 276-1723 $1 49 794 X 100 -Pin Edge -Card Board Connector. 79 556CN 276-1728 $2 1.39 For standard S -100 hobby computer bus 566CN 276 -1724 $2 99 1.69 Digital Car 276 -1554 4.99 each or 5719.95 gj 567CN 276-1721 $2.99 1.99 si DIP Header. 16-pin spacing Transformers 723CN 276-1740 5 99 694 Clock Module 741CN 276 -007 6 69 49C 276 -1980 1.29 6 -3 Volts 1.2 Amps. 11 /.x110 /,ex1n /,, 741H 276 -010 $ 69 490 Xi Right Angle IC Socket. Mount LED's 273 -050 2 29 276-1713 $1 39 16 3900N 990 vertically -pin spacing 6 -3 Volts, 3 Amps. 25,ex203/41 Just add switches and install! Type MA 10:3, 3909N 276 -1705 $1 29 990 275 -1985 1.49 273 -1510 3 99 with MOS /LSI clock circuit chip, lirEen 39115 276 -1706 $ 2 19 1.99 Metal Cabinet. 31/.x2360(4 12 Volts 5 4x2x21/2". Reg. 4558CN 276 -038 $ 99 790 Amps. 8.95. fluorescent display with four 0.3" digit:. F as 270 -251 2.59 75491 276 -1701 $1 49 99C 273-1513 Sale 6.95 2.09 MHz crystal, blinking colon activity indi- r. Metal Cabinet. 4x23xx6" 75492 276-1702 $1 49 990 18 Volts (Center Terminal), 4 Amps. Ideal cator. Six -pin edge- connector. Foi 7805 276 -1770 $1 59 1.29 270 -252 3.49 for 5V (using CT), or 12V solid -state regu- any 7812 51.59 Metal 61. 276 -1771 1.29 Cabinet. e27.x714" lators. 4x2x21h7 Reg. 8 95 12VDC source. 277 -1003 24 95 7815 276 1772 51.59 1.29 270 -253 4.49 273 -1514 ... Sale 6.95 Low -Profile DIP Sockets Experimenter's IC Socket 8 -Pin. 276-1995. Reg. 2 for $. 69 2/590 14-Pin. 276-1999. Reg. 2 for 51.19 2/894 PC Board Wrapping Tool .,,,, 18-Pin. 276 -1998. Reg. 2 tor $1.19 2/890 28 -Pin. 276-1997. Reg. 51.19 Each . 896 Simplifies 40 -Pin. 276-1996. Reg. 51.39 Each. 994 For making superior, precision connections - without sol- IC Projects dering. Wraps, unwraps, and strips 30-gauge wire. Modified wrap for extra security. No bits, sleeves or special skills 8- Rocker DIP Switch Ideal for two -circuit projects. Fire - needed. Balanced, 41/z" long. All- metal. 276 -1570 .... 6.95 retardant copper -clad board is only 14 -Pin Wire -Wrapping Sockets. 276 -1993 Pk. 2/1.29 Incorporates 8 on -off 21/2x5x1/16 ". Really simplifies inte- 16-Pin Wire- Wrapping Sockets. 276 -1994 Pk. 2/1.39 switches. For easy grated circuit projects by extending 50' Red Wire. #30 Gauge Kynar. 278-501 1 99 change of preset logic leads states. for easy soldering. 50' White Wire. #30 Gauge Kynar. 278-502 1 99 Fits any 16 -DIP socket. 276-151 2 99 50' Blue Wire. #30 Gauge Kynar. 278-503 1 99 275 -1301 ... 1.99

WHY WAIT FOR MAIL DELIVERY? & IN STOCK NOW AT OUR STORE NEAR YOU! Radio Prices May Vary at Individual Stores and Dealers ac A TANDY COMPANY FORT WORTH. TEXAS 76102 OVER 6000 LOCATIONS IN NINE COUNTRIES

www.americanradiohistory.com Nobody can replace all our replacements.

When it comes to replacement tubes, nobody has as many types as Sylvania -from power amplifiers to Nuvistors. We've got them for domestic and foreign TVs, radios and stereos, plus a full line for industrial applications. So, when you need replacement tubes come to the place that has everything -your Sylvania distributor. You'll find he's irreplaceable. MD SYLVANIA

www.americanradiohistory.com Radio- Electron ìcs. THE MAGAZINE FOR NEW IDEAS IN ELECTRONICS

Electronics publishers since 1908 DECEMBER 1977 Vol. 48 lo. 12

BUILD ONE 33 Optical Synthesizer Makes 3D Patterns ! w w w Fw w I h ti. OF THESE Use it with your scope for patterns galore. by Walter Sikonowitz Fti' w4 37 Digital Capacitance Meter 4 -digit LED readout makes reading values a cinch. by James Vernon SEASON'S

CCMPUTERS 48 Solving Secret Messages With A Computer How to use a microcomputer to decode secret messages. QREETINC;S by Fredrick W. Chesson

72 Z-80 Computer Corner A look at the pin -out of the Z -80 IC and the Z -80's timing. The editors and staff by William Barden, Jr. of Radio -Electronics CB RADIO 40 Build A CB Switcher Listen to AM or FM music between CB calls . . automatically, by George Santi join in sending 42 More Test Instruments For CB holiday greetings am Service instruments that make it easier. by Forest Belt our best wishes to; GENERAL 4 Looking Ahead ELECTRONICS Preview tomorrow, today. by David Lachanbruch a happy new year 45 Digital Car Clocks Part III: Final coverage of the many car clocks available today. by Fred Blechman

58 IC Bricklaying Construction technique for building IC- oriented projects into the smallest cases possible. by Walter T. Cardwell, Jr.

88 State Of Solid State Input analog signals to your microcomputer plus new UHF power transistors. by Karl Savon

70 Hobby Corner SCR, Triac, Diac and Quadrac -What they are, how they work. by Earl "Doc" Savage, K4SDS

STEREO HIGH- 51 AM Stereo FIDELITY The FCC is getting closer to selecting a system. Here's a preview of the ones being studied. by Len Feldman JIM 54 R -E Lab Tests Sylvania 2600 Receiver

o 56 R -E Lab Tests Onkyo TX -8500 Receiver o CB SWITCHER lets you listen to music I. wean CB calls ... automatically. Complet con- TELEVISION 66 Jack Darr's Service Clinic struction details start on page 40. Are matched transistors necessary?

86 Service Questions R -E's Service Editor solves technician problems.

EQUIPMENT 17 Fuzzbuster & Fuzzbuster II Radar Detectors FEPORTS 22 Triplett 60 -NA Ruggedized VOM Radio-Electronics, Published monthly by tie -sback Publications, Inc., 200 Park Avenue 24 Huntron Micro Probes Test Leads South, New k ark, NY 10003. Phone: 212 -777 -6400. Second-class pane }e paid at New York, NY and additional mailing offices Oe -year 25 UCE Microwave Monitor subscription rate: U.S.A., U.S. possessions and C snada, $8.75. Pan- American countries, $10.25. Other =Miles, 25 Audiovox MA -30 CB/FM AM -MPX Car Antenna $10.75. Single copies $1.00. ' 1977 by Gernsb, Publi- cations, Inc. All rights reserved. Printed in U.S: k. 26 Sencore TF46 Transistor & FET Tester Subscription Service: Mail all subscription orders, changes, correspondence and Postmaster 6 of :es of undelivered copies (Form 3579) to Radio-Eec 'onics DEPARTMENTS 98 Advertising Index 6 New & Timely Subscription Service, Box 2520, Boulder, CO 8)3 2. 12 Advertising Sales Offices 87 New Books A stamped self-addressed envelope must accor'F :ny all submitted manuscripts and /or artwork or phct g, xohs if 12 Editorial 88 New Literature their return is desired should they be relale:. We 14 Letters 78 New Products disclaim any responsibility for the loss or d..im ge of manuscripts and /or artwork or photographs wIr Ile al our 90 Market Center 89 Next Month possession or otherwise.

As a service to readers, Radio-Electronics publishes available plans or information relating to newsworthy products, techniques and scientific and technological devekgrtents. Because of possible variances in the quality and condition of materials and workmanship used by readers, Radio -Electronics disclaims any responsibility for the sale and Proper functioning of reader -built projects based upon or from plans or information published in this magazine. 3

www.americanradiohistory.com looking ahead

Super TV: If money were no object, what would manufactured by Sharp, contains a 10- pushbutton television be like? Every two years, at the Berlin programming panel that can automatically turn on the International Radio and Television Exhibition, we get a unit for unattended recording and that allows you to play chance to find out. This huge show features displays by all selections in any sequence, or to repeat any selection as the major western European consumer electronics many times as you want. A back -lighted liquid- crystal manufacturers. It includes such exhibits as large "walls" panel displays the time in either 12 -hour or 24 -hour consisting of color TV sets showing pictures with all modes, and acts as a memory- rewind counter, a tape having exactly the same color, tint and brightness values, counter, an elapsed -time indicator and program -selection thanks to the PAL color system, which, after many years, indicator. The cassette recorder will be available soon in we must concede works better than the U.S. system. the U. S. for about $300. Do you have any idea what this year's sensation is in European TV! It's a system that lets you watch two VTR price war: Repercussions of RCA's $1000 list price channels simultaneously. It is called "picture-in-the - on its Matsushita -built, four -hour -per- cassette picture," and lets viewers watch their favorite program videocassette recorder (Radio-Electronics, November, without missing the soccer game. On a 25 -inch color set, 1977) are still being felt throughout the industry, and it a black- and -white picture is inserted in a corner of the appears that a full -scale price war could occur, even screen. A remote -control tuning device allows you to though there is still a shortage of home VTR's. RCA's program any channel in the main part of the screen and price was $300 below the established price of the Sony any other channel in the corner. The receiver circuitry Betamax and other units. By press time, Sony and Zenith consists of virtually the equivalent of one color set and were sticking with the $1300 list price for their Beta - one monochrome set, with special IC's for isolation. (The format units, but some competing VTR's were definitely next trend may be a TV set that lets you watch three down in price. channels at a time!) Magnavox introduced its own VTR, also made by Another significant trend is complex microprocessor Matsushita in the same four -hour VHS format as RCA's; circuitry. Since more than 50% of German TV sets sold this unit has a suggested list price of $1075 to $1095, today feature remote controls, most of the new depending on the section of the country. Although this microprocessor circuitry is used to implement remote - price is nominally higher than RCA's, it will probably be control tuning schemes. Some remote systems are almost discounted to about the same level. unbelievably sophisticated. For example, one system that The Quasar Great Time Machine, which until now was has 30 pushbuttons and performs 48 functions (according the lowest -priced home VTR with a list of $995, is to the manufacturer) can program the set for up to four apparently coming down to about the $795 level, although years in advance; as many as 20 events can be stored - the suggested list price was officially unchanged at press turn on, turn off, change channel, etc. You can lock the time. There is some speculation that most prices can hold set to prevent children from handling the tuning -they until Christmas because of the short supply, but after the can watch only the shows that have been preprogrammed New Year, a new and lower price structure is expected to for them! develop. Almost every German TV manufacturer offers at least Price isn't the only battleground for videotape one model that can accommodate built -in or plug -in video recorders. Another major dispute is raging over recording games, thus eliminating an RF antenna connection and playing time. You may recall that when it was first because the game is connected directly to video circuits. introduced in 1976, the Sony Betamax cassette had a Some other sets provide for wireless infrared maximum recording /playing time of one hour. The VHS headphones. system, developed somewhat later by Japan Victor, could record two hours with a slightly larger cassette. Then, Super cassettes: Every few months some manufacturer Sony's half -speed version of Betamax(the one currently devises something new to extend the potential of the being sold) could record for two hours on the same record one hour of audio cassette, which was originally developed to record cassette that originally could only speech only, but is now recognized as capable of high - program material. fidelity recording. At the Berlin International Radio and TV Matsushita Electric (Japan Victor's parent company) to Exhibition, Austria's Eumig formally entered the cassette responded by doing to the VHS what Sony did in half, which in this case recorder field with a tape deck that uses an unusual Betamax -they cut the speed "electronic flywheel" speed control. Speed is maintained results in four hours -per- cassette. Now, Sony has cassette with by 15,000 corrections -per- second, based on optical announced two new developments -a can record up to three hours; readings of markings on a clear plastic flywheel. Eumig thinner (and more) tape that that accommodates specifications state that the deck has a frequency and a cassette -changer accessory six hours of unattended response of 20 to 20,000 Hz ± 3 dB, a 0.08% wow and two cassettes, making possible week -long cassette should be flutter and an S/N ratio of 73 dB with Dolby. The unit recording. At this rate, the goes on sale this year in Europe at around $1000 for the available within the year! deck; a complete system with AM /FM and a 50- watt -per- channel amplifier will cost $1500. American marketing is scheduled for next year. DAVID LACHENBRUCH A microprocessor -based cassette recorder, CONTRIBUTING EDITOR

www.americanradiohistory.com Your computer system needn't cost a fortune. Some computer kits include little more than a mother board and For just $35 you can add either a serial or parallel inter ace a front panel, and you pay extra for everything else you need to board. (And you won't have to buy several interfaces 001 a costly make an operating computer. board 'o get just the one you want.) SWTPC doesn't do it that way, so you can get your Southwest Peripheral Technical 6800 Computer up and running at a bargain cost Bargains

Your is no I _Dr compared with most other systems. It comes complete at $395 computer good without at least a termir with features that cost you extra with many other systems. entering data and viewing computer output, and you w it probably want a good method of storing programs arc -Jata. The Extras You Get We offer you a line of high -quality peripherals at Icvr F -ices These extras include 4K of random - access memory, a (You can prove this by just comparing prices.) mini -operating system in read -only memory, and a serial control Buy our CT -64 Video Terminal for only $325 and OUI C T-VM interface. They give you 1) a considerable amount of working Monitor with matching cover for $175. Our MF -68 Dual memory for your programs, 2) capability through the mini - Minifloppy costs just $995, complete with Disk BASIC a -d a operating system to simply turn on power and enter programs disk operating system. For cassette storage our AC -:0 without having to first load in a bootstrap loader, and 3) an Cassette Interface gives simple control for one or two cassette interface for connecting a terminal and beginning to talk with recorders. your computer immediately. You can get inexpensive hard copy with our PR -40 1r phanumeric Low -Cost Add -Ons Line Printer. We back up the 6800 system with low -cost softwa-t Now that you have a working computer, you'll probably want including 4K and 8K BASIC. to add at least two features soon, more memory and interfaces Compare the value you get with our computer ano teipher- for needed accessory equipment. Memory for our 6800 is als before you buy. We think you'll find that SWTPC gr'. e you another bargain. You can get 4K memory boards for just $100 more for your money in every way. and 8K boards for only $250. Our interfaces cost little compared with many other systems. Enclosed Is: Southwest Technical $995 for the Dual Minifloppy $250 for the PR -40 Line Printer Products Corp. $325 for the CT-64 Terminal $79.50 for AC -30 Cassette Inferfa, e $175 for the CT-VM Monitor Or BAC 31 219 W Rhapsoly, San Antonio. Texas 78216 # Exp. t $395 for the 4K 6800 Computer Or MC # Exp art London: Southwest Technical Products Co , Ltd. Tokyo: Southwest Technical Products Corp. /Japan Name Address City State Zip CIRCLE 69 ON FREE INFORMATION CARD

www.americanradiohistory.com new & timely

Calculator /watch performs more functions of add, subtract, multiply, divide, as considerable radio interference) are pro- than 36 functions percentage, net amount, change and re- duced by holes in the sun's corona. A six -ounce calculator, designed by peat, with the additional feature that if an These coronal holes are areas in which Hewlett- Packard, looks like a digital watch answer is greater than 104' or less than the magnetic -field lines open outward, the but has some unique features not found in 10 -4, the instrument switches to scientific density decreases, and a larger- than -usual other electronic timepieces. notation. amount of solar material is released into The model HP -01 has six basic interac- 6. The memory key stores time of day, the solar wind. The speed and the density tive functions (time, alarm, timer /stop- stopwatch interval, calendar date or of the solar -wind material are increased, numbers. Data can then be recalled for use and the wind passes the earth about seven in calculations or entered into time, date, days after the holes appear in the sun's stopwatch or alarm memories. Two addi- corona. Therefore, observers have discov- tional memories hold information to be ered they can get a week's warning before used in calculations or to perform arith- a magnetic storm strikes. metic operations. This information can be exchanged by pressing a button. RCA solar power converter uses The model HP -01 costs $650 (stainless low -cost plastic lenses steel) and $750 (gold -filled case). RCA Laboratories of Princeton, NJ, un- der contract to the U.S. Energy Research Radio Club of America announces and Development Administration (ERDA), 20 new Fellows has been developing their answer to the The Board of Directors of the Radio Club energy crisis. Their 300 -watt solar mod- of America, the oldest communications or- ganization in the world, recently voted in 20 new Fellows. The distinguished roster of engineers, scientists and executives in- cludes: Alan Armitage, Rex Bassett, Robert L. Batts, John Daly, Charles Davison, Gary Gray, Ray Griese, George Jacobs, R.W. Johnson, James McLean, Morgan McMa- hon, Tom McMullin, Travis Marshall, George Mitchell, Nat Pfeffer, Richard Ray Spence, Ben CALCULATOR /WATCH has 28 keys to perform Quantz, John Robinson, more than 36 different operations using six Tongue, and Val Williams. basic interactive functions.

watch, date /calendar, calculator and mem- Use of CB by police increases ory), controlled by 28 keys (six finger -acti- nationwide vated, 22 stylus- operated). A bright LED According to a recent survey conducted readout displays 12 different modes or by Inspector Robert Ellis of the Washing- indicators. What makes this instrument tru- ton, D.C., Metropolitan Police force, 94% of ly unusual is that you can use its six func- all state police organizations in the U.S. tions to perform an astounding number of have now established CB radio public - different operations. For instance: safety programs with an eye to providing 1. the time key once to show highway motorists direct access to police in Just press EXPERIMENTAL SOLAR SYSTEM from RCA use The survey reveals that 36 hours, minutes and seconds. You can emergencies. uses inexpensive plastic lenses to concentrate either a 12 -hour or a 24 -hour format, or states have installed CB radios in 48% of all sunlight directly onto silicon solar cells. The convert to and from decimal hours. Add or police vehicles, six states report CB's are in lenses concentrate the sunlight by a factor of subtract the time and the date is automat- all state patrol cars and an additional five 300, thus permiting the use of smaller and less ically adjusted. states plan such installations in the near expensive solar cells than normally used in 2. A beep alarm can be set up to 24 future. Only three states do not use CB conventional solar applications. hours ahead; a second timer -controlled radio communications or have arrange- alarm counts down from a preset time. ments with volunteer groups. ule's inexpensive, 4- inch -square plastic Another pushbutton displays setting time. "State public service agencies are not lenses, contained in a 6- foot -square mod- Whether the alarm is on or off is indicated the only agencies using CB radios," In- ule, concentrate the sunlight onto silicon automatically. spector Ellis notes. "Small towns, county solar cells. The system is self -powered to 3. A timer /stopwatch shows elapsed time and city public safety organizations are drive the tracking mechanism that keeps in hours /minutes /seconds, or in minutes/ also interfacing with CB radio users." the module continually pointing directly at seconds /hundredths of seconds. You can the sun to maximize output. store elapsed -time readings in memory. Geomagnetic storms caused by Although it is still too early to determine 4. The 200 -year calendar, set to either solar holes now predictable the system's eventual size and total output, month /day /year or day /month /year (useful For a long time, attempts have been RCA believes it can be mass -produced to outside the U.S.), can be used to calculate made to attribute the occurrence of geo- serve areas having little or no conventional past or future dates, the number of days magnetic storms to solar phenomena. power supplies. A small group of the solar between dates, or the day of the week or Now, observers have determined that modules could power a radio transmitter; year for any date. these storms (which are responsible for while a larger group could service a home 5. The calculator performs the usual some spectacular auroral displays as well or office in a sunny location.

www.americanradiohistory.com Chances are, someone you know just bought, a professional 31/2 digit DMM kit for less than `' 70.

Thousands of people have already bought the

Sabtronics Model 2000 . .. for two main reasons. First, its incredible accuracy, range and professional features. And second, the incredibly low price of $69.95. People everywhere appreciate this bench /portable multi - meter. They depend on its basic DCV accuracy of 0.1% ±1 digit, its readings to ±1999 and its five functions giving 28 ranges, overload protection and 100% overrange. The 2000 is automatically appealing to hobbyist and professional alike. With automatic overrange indication, automatic polarity, even automatic zeroing. Best of all, it's easy to assemble. All the parts you'll need, including the high- impact case, come right along with the clear, step -by -step instructions. The result is a professional quality 31/2 digit DMM that you could have paid a lot more than $69.95 for .. possibly receiving a lot less. But this one's from Sabtronics, specialists in digital technology. Maybe you should order yours before you turn the page.

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sabtronicsINC. INTERNATIONAL PO Box 64683 Dallas. Texas 75206 [214) 369 -7310

GUARANTEE: r ..,.,IMIN MIMI Our guarantee to you; examine the 2000 To: International, Inc. DMM kit for 10 days. If you're not satisfied, Sabtronics P.O. Box 64683, Dallas, TX 75206 return it unassembled for a full refund of purchase price. Please send me Sabtronics Model 2000 DMM E s) at $69.95 each. Jbtotal SPECIFICATIONS: DC volts in 5 ranges:100/1V to 1000V Shipping and handling, $5.00 per unit* Jbtotal AC volts in 5 ranges: 100µV to 1000V Texas Residents Add Sales Tax DC current in 6 ranges: 100nA to 2A TOTAL enclosed AC current in 6 ranges: 100nA to 2A Name Resistance: 0.152 to 20Mí in 6 ranges AC frequency response: 40Hz to 50KHz Street Address 9mm (.36 ") LED display Input impedance: 10Mí City Size: 8 "W x 6.5 "D x 3 "H (203W x 165D x 76H mm) State Zip

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www.americanradiohistory.com editorial Radio-Electronics® Hugo Gernsback (1884 -1967) founder M. Harvey Gernsback, KOD -6694 editor -in -chief and publisher Larry Steckler, KTX -3644, CET, editor Arthur Kleiman, KTZ -3288, managing editor Robert F. Scott, CET, W2PWG, KXK -8533, technical editor For the want of a nail.. Sonia Greenbaum, copy editor Jack Darr, CET service editor Leonard Feldman We all know that story. How the battle was lost because of one contributing high -fidelity editor horseshoe nail. But what many of us don't seem to know is that Karl Savon, semiconductor editor contributing editor many construction projects don't work because of one '/a -watt David Lachenbruch, Earl "Doc" Savage, K4SDS, hobby editor carbon resistor . . . . or one PNP transistor . . . . or one MOS Vincent P. Cicenia, production manager IC . . . . or one . . . . Harriet I. Matysko, circulation director Sheila Wertling, circulation assistant Radio -Electronics publishes more than 25 construction articles Arline R. Bailey, advertising coordinator every year. Some are simple and almost foolproof. Many are complex, state -of- the -art machines. And all it takes is one out -of- Cover design by Louis G. Rubsamen Cover photo by Michael Wilson spec component, or one wiring error to keep it from working. Radio Electronics is a member of the Insti- A while back we got a letter from a reader who had built an audio tute of High Fidelity and is indexed in & Technology Index and mixer. He complained that it was noisey. He couldn't understand Applied Science Readers Guide to Periodical Literature. the problem. He had followed the article precisely. Except for the transistors, he used only the parts specified in the parts list. Too bad he hadn't used low -noise transistors like the ones specified. He did not have to use the specific ones we listed, but in making a substitution to use available parts, he forgot one of the most important specifications for the device he was building. He remembered the collector voltages, he didn't forget to obtain an Radio -Electronics magazine is published NPN device, he watched for the output power ratings, but he by Gernsback Publications, Inc. forgot about the noise specification. More recently a reader 200 Park Ave. S., New York, NY 10003 (212) 777 -6400 completed our 2650 computer. It worked well, except . . . . To M. Harvey Gernsback make a long story short, a memory IC inserted backwards was President: the problem. Vice President: Larry Steckler Treasurer: Carol A. Gernsback The point of this all is that we select construction projects to Secretary: Bertina Baer provide you with the latest, most interesting devices to build that ADVERTISING SALES we can find. In many instances, if you didn't build them, you EAST are a real yet they will work as couldn't own one. Most challenge, Stanley Levitan, KZA -5580 soon as you hook up the power supply and turn on the switch. Radio -Electronics But when they don't, consider the possible problems carefully. 200 Park Ave. South Make sure there are no solder bridges on the circuit board and New York, NY 10003 that there are no cold solder joints. Check the symptoms and the (212) 777-6400 parts involved. Double check wherever you have made a MIDWEST /Texas /Arkansas /Okla. substitution or a modification to the circuit, because that is one Ralph Bergen, KXD -8396 of the most likely trouble spots. Don't lose your project for the The Ralph Bergen Co. 6319 N. Central Ave. a want of nail. Chicago, IL 60646 (312) 792-3646 PACIFIC COAST Mountain States Jay Eisenberg, KYF -3277 J.E. Publishers Representative Co., 8732 Sunset Blvd., 4th Floor, Los Angeles, CA 90069 (213) 659 -3810 Sales Mart Building 1485 Bayshore Blvd., Box 140 LARRY STECKLER San Francisco, CA 94124 Editor (415) 467 -0125 SOUTHEAST J.E. Publishers Representative Co., 214 -387 -2424

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www.americanradiohistory.com 15MHz Ietlers Triggered Sweep TRS -80 USERS GROUP underlying point is that of the proper mix of A new TRS -80 Users Group is in the theory and practice in circuit design (which process of being formed. The group is was also behind my statement that all Trace circuits had actually been constructed). Dual dedicated to the exchange of programs and technical data for Radio Shack's new First, understand that I am not antago- Z -80 -based system. For information, write nistic toward theory; in fact, I use it to the a Scope to R. Gordon Lloyd, 7554 Southgate Rd., limits of my knowledge. Yet, I am of prac- Fayetteville, NC 28304. tical turn of mind, and you sent me to my I R. GORDON LLOYD books to double -check your specs, where Usable to Fayetteville, NC found two different specs for loH for 7400's, and then to my workbench. I had to find out if the circuits I had built, including one I 30 MHz DESIGN ERROR have used for over two years, were only In the September 1977 "Hobby Corner," flukes. Earl Savage makes the statement that I designed a circuit to check 7400 gates since he has built all the circuits shown in for both the ability to source sufficient LED the column and they worked, any problems current and at the same time produce highs a reader has cannot be traced to bad and lows acceptable to other gates. In circuit designs. In making the statement, he summary, each of the one hundred and neglects the device-to- device variability al- thirty -six 7400 gates I had on hand dem- lowed by the spec sheets. In fact, the pulse onstrated the capability of performing both switch shown in Fig. 6 contains a design functions. Not one failed in the test proce- error, as well as a typographical error. dure which required some 140,000 state The typographical error concerns the red changes. (As I write this, there are two LED. This LED is connected backwards. 7400's in the test circuit that have been The more subtle error involves the green continuously operating for the last 42 LED. This LED is designed to be on when hours -or over 60 million state changes for the NAND gate has a high -state output. The each gate!) A number of gates did have TTL data sheets show that in the high state, some current leakage through the red LED an output is only required to source 10 X and in eight of these, the optical perfor- 40 pa = 0.4 mA of current. If the gate is mance was marginal although usable were quite func- B &K- PRECISION MODEL 1472C $740 putting out 2 volts, (the absolute minimum (these two ceramic IC's INCLUDING PROBES safe voltage for the high state) and the LED tional electronically -there was no obser- voltage drop is near maximum at 1.6 volts, vable distortion of the square -wave output Normally rated at 15MHz ( -3dB), the current required is still (2.0 - 1.6)/ 270 pattern). Furthermore, the average source it easily syncs and displays a = 1.5 mA. Thus, the required current is voltage (VOH) was +3.34 VDC (per specs), 30MHz signal with sure triggering. almost four times what the spec sheets and the average source current (lo) was 3.3 mA. Quite obviously, the latter is impos- Automatically selects chopped require the device to provide. The result is that perfectly good 7400 IC's will yield an sible according to the published specs! or alternate trace display the output voltage below 2 volts, and this Why does it work? I don't know, unless Maintains calibration accuracy voltage may or may not be interpreted by specs deliberately understate the capabili- ty of the upper transistor in the totem -pole over 105- 130VAC range. another gate as a logic 1. In fact, the other NAND gate in the circuit may be affected this output by a considerable factor. 11 sensitivity ranges, 10mV to way since it is connected to the output. In any case, I do not believe that all these 20V /cm. The solution is quite simple. Connect the 7400's are similarly atypical, especially green LED to the output of the other NAND since my stock has been purchased at 19 sweep ranges, 0.5ASEC to gate in the circuit in the same manner as various times and from several suppliers. 0.5SEC /cm. the correct connection of the red LED. Therefore, based on my past experience I feel in my 24nSEC rise time. Although a TTL output only has to source and upon these tests, justified 0.4 mA, it is required to be able to sink 16 design. This is another case in which theory Front panel X -Y operation with mA. and practice apparently do not agree and matched phase -shift and PROF. WILLIAM D. OHLSEN that further emphasizes that they must be sensitivity inputs. The University of Utah judiciously mixed. Salt Lake City, UT EARL R. SAVAGE P31 blue phosphor Hobby Editor

Algebraic addition 1. As soon as one says something won't and subtraction go wrong, it does! Several sharp -eyed NO AM DATA Available from your distributor. readers called attention to the reversed LED. I recently picked up a copy of your June 2. The hobbyist, technician or engineer issue and saw your Lab Test article on a :41(PRECISION who ignores possible device variability is Fisher model RS -1080 AM /FM receiver. asking for trouble, as was stated in the You had very extensive test results on both DYNASCAN caution regarding component tolerance. the FM tuner section and the amplifier CORPORATION 3. The matter of the design calling for a section. The written comments were also useful to the average consumer. 6460 West Cortland Avenue gate to source sufficient current for the Chicago, Illinois 60635 312/889 -9087 LED is correct, up to a point. Much As an engineer of an AM radio station in In Canada Atlas Electronics Ontano depends on whose specs you accept for a large metropolitan market, I was appalled Intl Sls Empire Exp. 270 Newtown Rd Plainv,ew LI NV 11803 your calculations. Published specs do not to note that not one measurement was always agree for a given IC. However, the continued to page 16 CIRCLE 64 ON FREE INFORMATION CARD

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www.americanradiohistory.com LETTERS to make good AM tuners. additional mention, and, in those instances, continued from page 14 If these problems are inherent in the we do refer to the AM section in somewhat majority of AM tuners, the public should greater detail. In general, however, most

know about it. I think that a reputable AM tuner sections we have tested have taken on the AM tuner section, with only magazine such as yours has the ability and poor frequency response above around 3 vague written references that pertained to the duty to do something about this. I am kHz or 4 kHz, and also exhibit high har- that section. How can a consumer make an sure that if consumers were shown that monic distortion at 30% modulation levels. intelligent selection on a receiver when they they could have better sound quality for As you have stated, a great many AM are given no data on half of it? only small increases in product price, they stations consistently modulate to much In Canada, AM captures by far the ma- would soon demand it. If they are kept in higher average levels than that, and so you jority of the listening audience. Perhaps the dark, they will not expect better AM can just imagine what horrendous distor- you feel that AM is not of sufficient quality quality from their tuners and accept what tion levels are delivered by "typical" AM to justify sophisticated tests on an AM they now have, which I feel is, in some tuner sections under these circumstances. tuner. If so, I would question why. Are you cases, deplorable. There is one glimmer of hope, however. aware that stations like ours broadcast My motives for this letter are obvious - As you know, the FCC has recently issued a clean signals with less than .5% THD from as FM continues to make inroads into the notice of inquiry that may well lead to the

50 to 10 KHz ±2 dB? I realize that these AM market, we must improve our own promulgation of broadcast standards for are only two specs but they are very impor- product to combat this. As a broadcasting stereo AM. If such standards are formu- tant ones. They were obtained by sampling engineer, I feel that presently one of the lated, and if stereo AM broadcasting be- RF from each of the towers in the array, weakest links in the system is the tuner, gins in this country in the near future, and feeding them into a phase monitor and and therefore, feel that if improvements perhaps more U.S. stations will find it then feeding the output to a storage scope can be made, they should be. I also think economically feasible to lease 15,000 -Hz with a spectrum analyzer contained within that this must begin with consumer educa- lines from our phone companies to feed it. From these and many other tests, we tion which only you can do. their programs from studio to transmitter. know that our signal is good. KEN DITTRICK, Assistant Engineer (Presently, most use "standard" 5,000 -Hz Naturally, we don't sound like an FM Radio Station CHED Ltd. lines, which limit broadcast fidelity to begin signal simply because AM material is gen- Edmonton, Canada with.) If enough stations start "cleaning up" erally processed for a loud signal with high their signals and begin to transmit a wider average modulation levels with positive We are in complete agreement with your audio bandwidth, perhaps hi -fi manufac- peaks reaching the legal limit of 120 %. comments regarding the generally poor de- turers will then have the incentive to im-

I have done several tests on various sign practices followed by manufacturers prove their circuit designs. If and when types of AM receivers. I will, for the sake of of high -fidelity receiver components in the such improvements are noticed by our space, discuss only one test -frequency AM tuner sections of their products. It is testing staff, you can be certain that we will response. I have found that due to inexpen- precisely for this reason that we pay so little offer more definitive data regarding AM sive IF sections and other glaringly bad attention to AM performance in testing and performance of the products we test and design errors in AM tuners, this spec has reporting upon various tuners and re- evaluate. suffered. I believe that this occurs mainly ceivers. From time to time, we do run LEN FELDMAN due to "cost engineering," not the inability across an AM tuner section that merits CONTRIBUTING HI -Fl EDITOR

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Electrolert Fuzzbuster and beam through a hill or around a curve, you too broadly tuned, it is subject tc false trig- must depend again on beam scattering to gering from RF sources other that t ie police Fuzzbuster II Radar receive a signal. The operators' manual pro- radar. For the X -band, both FAz r busters, vided with the Fuzzbuster and Fuzzbuster II according to Electrolert, will deter; a signal in Detectors contains several illustrative examples of such the 10.45- to 10.6 -GHz range. situations. Since the Fuzzbusters are not Haterproof, Selectivity is the other important perfor- they should not be mounted extern.111, such as mance specification. If the radar detector is continued cn -,age 22

NEW FROM LEADER CIRCLE 79 ON FREE INFORMATION CARD The Sensitive 80M Hz PERHAPS THE BEST KNOWN OF ALL THE RADAR detectors on the market is the Fuzzbuster, manufactured by Electrolert, Inc., 4949 South 7 -Digit Counter 25A, Troy, OH 45373. This company has most recently introduced the multiband Fuzz- Bright 1/2" Display Period Function 5ppm Accura buster II. determines precise pulse width. Police radar units operate on either one of two frequencies: a primary frequency of 10.5 GHz (X -band) and a secondary frequency of 24 GHz (K- band). Approximately 90% of all police radar units operate on the X -band. However, the remainder operate on the K- band frequency. The Fuzzbuster II monitors both frequencies automatically without your having to flip a band switch. The original Fuzzbuster monitors only the X -band. Other- wise, the units are identical. Both Fuzzbusters are housed in a black metal 51/9 X 3' /e X 2'A-inch case with a simu- lated woodgrain front panel. The front panel contains a 1- inch -diameter indicator light and Gatetime a sensitivity control. The receiving antenna is Indicator located behind a plastic- covered diamond - shaped cutout on the back panel. An audible Overrange indicator is also located behind several holes in Indicator the back panel. Selectivity and sensitivity High Reliability 20mVRMS Sensitivity Selectivity and sensitivity are the two most 1MSt Input LSI Circuitry -- Variable important performance specifications for ra- Impedance dar detectors. Sensitivity is the minimum signal that is needed to trigger the detector. In effect, sensitivity is a measure of the distance from the police radar unit that the motorist Compare Features, will be alerted to its presence. Police radar units have an approximate '/-mile range. They emit a narrow beam for a much greater Accuracy, Sensitivity. distance, but can only measure speed at a ' /2- mile distance or closer. Electrolert claims that the Fuzzbuster and We'll be Number 1. Fuzzbuster II have a sensitivity that is six times better than that of the police radar units. Model LDC-822 S299.95 with accessories. This does not necessarily mean, however, that See your distributor or write direct for details the Fuzzbuster can detect the radar unit at a distance of three miles. You must keep in mind that the radar emits a narrow beam. The Fuzzbuster must receive energy from the 151 Dupont Street, Plainview. N.Y. 11503 beam to detect its presence. Your car must be (516) 622 -4300 either within the narrow beam or depend on In Canada. Ltd., Montreal. Quebec beam reflections (scattering) from other vehi- Omnitronix. cles or stationary objects along the road. Also, because the Fuzzbuster cannot detect the CIRCLE 56 ON FREE INFORMATION CARD

www.americanradiohistory.com At CIE,you get electronics career training from specialists. If you're interested in learning how to fix air conditioners, service cars or install heating systems - talk to some other school. But if you're serious about electronics, come to CIE -The Electronics Specialists.

Special Projects Director Cleveland Institute of Electronics

www.americanradiohistory.com Plus there's a professional quality the exams get their Licenses. You My father always told me that oscilloscope you build and use to may already know that an FCC there were certain advan- "see" and "read" the characteristic License is needed for some careers tages to putting all your eggs in one waveform patterns of electronic in electronics -and it can be i. basket. "John," he said, "learn to equipment. valuable credential anytin-e. do one important thing better than anyone else, and you'll always be You work with experi- Find out more: Mail this in demand." enced specialists. card for your FRET; I believe he was right. Today is When you send us a completed CATALOG today: the age of specialization. And I lesson, you can be sure it will be If the card is gone, cut c to and think that's a very good thing. reviewed and graded by a trained mail the coupon. Consider doctors. You wouldn't electronics instructor, backed by a I'll send you a copy of CAE's expect your family doctor to perform team of technical specialists. If you FREE school catalog, along w th a open heart surgery or your dentist to need specialized help, you get it fast complete package of independent set a broken bone, either. Would you? ... in writing from the faculty spe- home study information. For these things, you'd want a cialists best qualified to handle For your convenience, Tll try to specialist. And you'd trust him. Be- your question. arrange for a CIE representat ve to cause you'd know if he weren't any People who have known contact you to answer any que .tions good, he'd be out of business. us a long time, think of us you may have. Why trust your education Remember, if you are serious as the "FCC License about learning electronics ... and career future to School." building upon your present skills, anything less than a We don't mind. We have a fine your best bet is to go with the '.lec- specialist? record of preparing people to take .. . tronics specialists -CIE. Mail the You shouldn't. And you certainly and pass ... the government - card or coupon today or write CIE don't have to. administered FCC License exams. (and mention the name and date of FACT: CIE is the largest inde- In fact, in continuing surveys nearly this magazine), 1776 East 17th pendent home study school in the 4 out of 5 of our graduates who take Street, Cleveland, Ohio 44114 . world that specializes exclusively in electronics. We have to be good at it because we put all our eggs in one basket: electronics. If we hadn't done a good job, we'd have closed our doors long ago. Specialists aren't for everyone. I'll tell it to you straight. If you think electronics would make a nice hobby, check with other schools. But if you think you have the cool - and want the training it takes - to make sure that a sound blackout during a prime time TV show will be corrected in seconds -then answer this ad. You'll probably find CIE has a course that's just right for you! At CIE, we combine theory and practice. You learn the best of both. Learning electronics is a lot more than memorizing a laundry list of facts about circuits and transis- tors. Electronics is interesting be- cause it's based on some fairly recent Patterns shown on TV and oscilloscope screens are simulated. scientific discoveries. It's built on ideas. So, look for a program that starts with ideas - and builds on them. That's what happens with CIE's Cleveland Institute of Electronics, Inc. Auto -Programmed® Lessons. Each 44114 lesson uses world -famous CIE 1776 East 17th Street, Cleveland, Ohio "programmed learning" methods to Accredited Member National Home Study Council teach you important principles. You YES ... John, I want to learn from the specialists in electronics -CIE. explore them, master them com- Send me my FREE CIE school catalog - including details about troubleshon ! ; pletely ... before you start to information. , e Icourses - plus my FREE package of home study te apply them! But beyond theory, some of our Print Name courses come fully equipped with Address Apt the electronics gear to actually let you perform hundreds of checking, City testing and analyzing projects. State lip In fact, depending on the course you take, you'll do most of the basic Age Phone (area code) things professionals do every day - things like servicing a beauty of a Check box for G. I. Bill information: Veteran Active Duty Zenith color TV set ... or studying a Mail today: variety of screen display patterns with the help of a color bar generator.

www.americanradiohistory.com EQUIPMENT REPORTS multiplier switch to X2 to move this reading continued from page 17 to 0 -300 mV. Six resistance ranges start at X 1, with a 6- behind the front grill of the car. The best loca- ohm center scale, and go to a X 100K range at 100 megohms. tion is on top of the dashboard inside the vehi- This increased number of cle. Four self- adhesive Velcro fasteners permit ranges makes the instrument more useful easy removal of the detector when necessary. wherever high -value resistors are found. The resistance Electrical connection is simple. The power high- values can be read in the center the scale. cord comes complete with a plug that fits into half of most dashboard cigar lighters. Both Fuzzbus- The model 60 -NA has an improved accura- cy ± I '/2% ters work on 12 -volt positive or negative of of full scale on all voltage ranges; ± ground electrical systems with no modification the AC accuracy is 3% of full scale on all necessary. voltage ranges. A polarity- reversing switch on To set the sensitivity control, rotate it fully the panel works on both DC voltages and DC current, as well as on the clockwise. The indicator will light up and a ohmmeter. This tone will be heard. Now, rotate the control switch is handy for transistor junction tests. counterclockwise until the light goes out and All the safety and construction features of the audible tone turns off. the earlier model 60 have been retained. This unit is drop proof; it will withstand an acci- If the unit does not operate properly, check CIRCLE 80 ON FREE INFORMATION CARD the indicator light. Remove the plastic lens dental drop from five feet onto a cement floor from the front panel and replace the No. 47 or even a deliberate drop, and there are no DC voltages and DC current indicator lamp. (A spare indicator lamp comes on four handy exposed metal parts on the case. Even the test - meter scales of the 0-5, 0-15 type. Readings lead jacks are recessed with the unit.) R -E so that no wires are start at 0.5 volt, then proceed to 1.5 volts, 5.0 exposed. The meter movement has a special volts, 15 volts, etc. (Actually, there is a lower suspension. Triplett Model 60 -NA range; wait a minute.) The range goes to 500 The model 60 -NA is well protected elec- volts and a multiplier switch doubles the full - tronically. A diode unit protects the meter Ruggedized VOM scale reading on each range so that the top movement. A 1/2-amp fuse and a I.0 -amp fuse, THE TRIPLETT CORP., BLUFFTON, OH 45817, MAN - range is 1000 volts or 1000 mA. The first set of used in series with the inputs, insure that all ufacturers of the Series 60 ruggedized readings is at 20,000 ohms - per -volt, and dou- ranges are as safe from damage as possible. VOM's, have expanded the Series 60 line by bled readings are at 10,000 ohms -per -volt. Therefore, while you still can't read the AC adding the model 60 -NA, which sells for Extra scales for the 0-3 (0-1.5 volts doubled) line voltage on the XI ohms scale, it will not $136. and 0-10 ranges permit direct reading of these affect anything except the '/N -amp fuse. The model 60 -NA resembles the original ranges. The AC voltage ranges are frequency - A separate 2 -amp fuse protects the instru- model 60 VOM, and possesses all the rugged- compensated from 20 Hz to 20 kHz. ment and the operator against damage if over - ness of the earlier unit, but is designed for even For the other DC voltage range (0-0.15 voltage blows the small fuses and arcs over the greater versatility. volt, or 150 mV), simply set the range switch holders. This additional fuse is a special 1 -kV, The model 60 -NA has a total of 50 separate to the 0-0.5 DCMA position. The meter then Bussman HVA -2 or Littelfuse 621002 fuse. ranges. (I counted them!) You can read AC or becomes a 0-150 mV DC voltmeter. Set the continued on page 24 wire wrapping center ó BATTERY WIRE WRAPPING TOOL MODEL BW 6301 ANOTHER UNIOUE PRODUCT DESIGNED, MANUFACTURED AND MARKETED WORLDWIDE

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CIRCLE 77 ON FREE INFORMATION CARD

www.americanradiohistory.com The Sinclair PDM35. A personal digital multimeter for only S49'5 Technical specification DC Volts (4 ranges) Range: l mV to 1000 V.

Accuracy of reading 1.0 %± 1 count. Note: 10 M I I input impedance. AC Volts (40 Hz -5 kHz)

Range: 1 V to 500 V. Accuracy of reading: 1.0 %± 2 cow-1.i. DC Current (6 ranges)

Range: 1 nA to 200 mA.

Accuracy of reading: 1.0 %± 1 coun: Note: Max. resolution 0.1 nA. Resistance (5 ranges)

Range: l I 1 to 20 Mi 1. ; í Accuracy of reading: 1.5% ± 1 coon:. Also provides 5 junction -test range:-. Dimensions: 6 in x 3 in x 1'/2 in. Weight: 61/2 oz. Power supply: 9 V battery or Now everyone can afford to Operation from replaceable battery Sinclair AC adapter. own a digital multimeter or AC adapter. Sockets: Standard 4 mm for A digital multimeter used to Industry standard 10 M I i input resilient plugs. mean an expensive, bulky piece of impedance. Options: AC adapter for 117 V equipment. 60 Hz power. De -luxe padded The Sinclair PDM35 changes Compare it with an carrying wallet. 30 kV probe. that. It's all the functions and got analog meter! The Sinclair credentials features you want in a digital The PDM 35's 1% of reading Sinclair have pioneered a whol multimeter, yet they're neatly compares with 3% full for a of scale range of electronic world- firsts -fro in packaged in a rugged but light comparable analog meter. That programmable pocket calculators pocket -size case, ready to go makes it around 5 times more to miniature TVs.The PDM35 anywhere. accurate on average. embodies six years' experience in The Sinclair PDM35 gives you The PDM35 will resolve I mV digital multimeter design, in which all the benefits of an ordinary digital against around 10 mV for a time Sinclair have become one of multimeter - quick clear readings, comarable analog meter - and the world's largest producers. high accuracy and resolution, high resolution on current is over 1000 Tried, tested, ready to go! input impedence. Yet at $49.95 times greater. The Sinclair PDM35 comes to it costs less than you'd expect to pay The PDM35's DC input you fully built, tested, calibrated and for an analog meter! 1 impedance of 10 M f is 50 times guaranteed. It comes complete vith The Sinclair PDM35 is tailor - higher than a 20 k I I /volt analog leads and test prods, operating made for anyone who needs to make meter on the 10 V range. instructions and a carrying wallet. And rapid measurements. Development The PDM35 gives precise getting one couldn't be easier. :1_ st all engineers, field service engineers, digital readings. So there's no need to in the coupon, enclose a cheque " I O lab technicians, computer specialists, interpret ambiguous scales, no for the correct amount (usual 10 -day radio and electronic hobbyists will errors. no parallax There's need to money -back undertaking, of coL.rz e), find it ideal. reverse leads for negative readings. and send it to us. With its rugged construction There's no delicate meter movement We'll mail your PDM35 byre :.lrn! and battery operation, the PDM35 is to damage. And you can resolve perfectly suited for hand work in the current as low as 0.1 nA and measure Sinclair Radionics Inc, Galleria, field, while its angled display and transistor and diode junctions over 115 East 57th Street, New York, optional AC power facility make it 5 decades of current. 10022, U.S.A. just as useful on the bench. ---n 'l o: Sinclair Radionics Inc, Galleria,115 East 57th Street, New York, N.Y. 10022, U.S.A. What you get with a PDM35 Please send me (qty¡ PDM35(s) Name 31/2 digit resolution. @$49.95 plus $1.05 postage and Sharp, bright, easily read LEI) insurance each. $ Address display, reading to ± 1.999. (qty) De -luxe padded Automatic carrying case(s) ©$4.95 each $ City polarity selection. (qty) AC adapter(s)n$4.95 Resolution of 1 mV and 0.1 nA each.$ State 0.00014 A). I enclose check /M() order made out to Sinclair Radionics Inc (indicate total order value. Zip Direct reading of semiconductor Add 4% sales tax for NYS deliveries). $ forward voltages at 5 different currents. I understand that if I am not completely satisfied Resistance measured up to 20 MI I. with my PDM35, I may return it within ten days SInClllr ¡ Lor a full cash refund. World leaders in fingertip elc rots. 1% of reading accuracy. CIRCLE 19 ON FREE INFORMATION CARD

www.americanradiohistory.com EQUIPMENT REPORTS JACK DARR, Service Editor of continued from page 22

The fuses are easily accessible; just remove the battery cover from the back of the VOM. They are contained in spring -clip holders, together with spare fuses for each one. Radio-Electronics One D -cell battery is used for the lower ohms ranges, and a 30-volt (NEDA No. 210) reports on the battery is used for the two high ohms ranges. Both batteries are accessible; the battery com- partment, which is separate from the circuit board, is sealed to protect the rest of the meter from any possible leakage. (If you've ever had to clean up a VOM after a battery has leaked, you'll appreciate this feature.) Several accessories extend the model 60- NA's ranges. The model 10-C Clamp-On NU -COLOR Adaptor reads AC current. The model 10/ Line Separator allows you to read AC currents PICTURE at any regular outlet. For DC current readings greater than the 1 -amp range, a separate TUBE shunt adapter can be used. Currents up to 30 amps can be read. For DC high voltages, the RESTORER model 79 -380 probe extends the range to 30 Picture kV; for AC high voltage, the model 79 -381 Model 90A probe gives 30 kV AC. Oneida The instruction manual gives full details of HAD TO ranges, scales (a useful chart on page 11 shows Restorer WHOWAITS.t Tube TO HIM finally found just exactly how to read all those ranges), and cali- COME I ALL while, but made by bration tests and adjustments. Four calibra- a new device, for quite A are used on the 3 -VAC and wait I needed: Company.Comp tion adjustments the thing Manufacturing picture tny. 150 -VAC ranges, on the 50-mV range and on Oneida EElectronic odel Nu-Color restore The mirror -scale meter move- model 90A to the µA range. This is theTh is designed or more ment has a 4.5 -inch arc to eliminate parallax. with one restorer. tubes The modular design of the meter makes it easy old picture to picture to repair in an emergency. color TV, with a weak guns. Wards believed. For minor troubleshooting, there is a built - a trade-in seen to be 1 had the set the range switch it had al emission; in "confidence test." Just tube so bad almost norm to X 1K, short the test leads and adjust the read the The blue gun up to ed gun ohms scale to zero. Remove the slip -on test gun would come and green on the meter: clip from the red lead and touch the test jack ono sector The meter should read exactly this the wiggled the is a plug-in on the panel. barely 90A tube the top just odel the picture half -scale; there is a small red block on The Nu-Color between it is scale for this purpose. If the needle stops inside device is inserted However, of that is OK. device like a brightener. usual sense this block, everything socket,soc at least i and is a little The manual contains a few handy hints, and brig htener, socket lives up not a controls, one such as: "Don't move the range switch without slide the word. color-coded disconnecting the load." This protects the three posi box with OFF switch contacts from possible arcs, etc., and to its each color. the for controls them last longer. This tough and with all m and turned makes Starting a bright should provide full the Nu-Color was CoIOr accurate little instrument plugged the raster value for the money in long, dependable claims tion, cted, of the set onl the controls Ncuu-or service. R -E adjusted looking blue. and and its and cane grey scale ng the color picture. ddl excellent con- Huntron Micro- Probes pattern. gave an controls with name... normally, thing s looked Telescopic Test Leads Reds saturated all other claims and up to its all the lives the trol This did "restore very certainly name. and gs the Nu- this old explain, color" to careful to for cola Oneida cure-all' M problems is correct Color will helps The d- but emission. the hone troubles, picture-tube in unbalanced and adjusted canc installed vice little trouble. with very Order a supply today! FALL SPECIAL...Buy 6, get the 7th FREE Write us direct or call your Oneida distributor for decals Offer expires Dec.15th 1977

CIRCLE 82 ON FREE INFORMATION CARD ELECTRONIC MFG. INC. THE LITTLE THINGS IN LIFE ARE ALWAYS IM- eida portant. You can have a fine, accurate and expensive voltmeter, but if you can't connect it P.O. Box 678,Baldwin Street Ext., Meadville, Pa. 16335 Phone (814)336 -2125 to the circuitry you want to check, it's as much CIRCLE 57 ON FREE INFORMATION CARD

www.americanradiohistory.com use as an empty cigar box. So, in such a case, think that more heat has been generated It is very simple to operate; even 1 did it what can you use? The answer is -test leads! outside the ovens than inside.) To help settle right the first time. Just turn the oven on, I'm much impressed with something new - the controversy, a compact, accurate leakage remembering to put a glass of water irside as a some ordinary -looking test leads called Micro- detector is needed. dummy load. Now, holding the meIer 2 inches Probes that are manufactured by Huntron UCE, Inc., 20 North Main St., Norwalk, (5 cm) from the door near the seal,-, tnove the Sales, Inc., 15123 Pacific Highway North, CT 06854, has now produced a portable radi- meter all the way around the io)r. Any Lynnwood, WA 98036. One lead is red and ation detector, the Microwave Monitor model leakage will show up instantly. We decked it the other lead is black, but the similarity ends out on several units, including cirnmercial there. The lead tip is very sharp and consists of ovens. The maximum reading was a 'out 1.0 a well -insulated rod. You can telescope the tip mW, which is well within safe limit! . he stan- to an extension of 2.75 inches beyond the end dard maximum reading set by the .S. De- of the probe body. A locking collar holds the partment of Health, Education and 1; elfare is tip tightly in the desired position. The V.-inch- 5.0 mW/cm2. diameter probe body has a small collar that The model 245M is self- powere an edu- makes them easier to hold. The leads are made cated guess is that it uses a mic-c.immeter of I8 -gauge Superflex wire, and can be termi- with a 2,450 -MHz detector circuit nated in any type of connector. Mine have Microwave oven technicians wad,: find this banana plugs that fit most of my equipment. instrument very useful since it taIa only 30 Since so many TV sets have their tran- seconds to run a complete leakag, st after sistors, resistors and other parts so tightly repair and reassembly. The test -e.i s could packed on the circuit board that only a small even be noted on the statement 'en the part of the lead is visible, a very long, thin test - concerned consumer could use this tic lector to probe is essential to check test points. Because check his own microwave oven for .alcty. It is a great many parts are always in the way, the reasonably priced, and with mir ::: al care probes must be very well insulated. The should last a long time. R -E Micro-Probes' insulation covers all but the very end of the tip. This allows you to take readings between two adjacent IC pins on any Audiovox MA-30 Electric two transistor leads, etc. I've rigged some items to do this sort of job CIRCLE 81 ON FREE INFORMATION CARD CB/FM-AM-MPX Antenna in the past, but none perform as easily and THE THOUGHT OF BEING ABLE 1D REPLACE safely as the Micro-Probes. R -E 245M, priced at $49.95. This detector is no my factory installed AM /FM car ra.: io anten- larger than the palm of your hand, and is na with a single antenna that w II work on completely self -powered, no batteries are AM, FM and CB was like a dreary come true. UCE, Inc., 245M Microwave needed. It is calibrated to 5.0 mW/cm2 center I could get rid of the magnetic CB .vr p on the scale, and levels as low as 0.5 mW can be read. roof, not have any antenna at all l isible when

Monitor The model 245M is factory -calibrated against parked on the street and still get .: d perfor- MICROWAVE OVEN LEAKAGE HAS LONG BEEN a U.S. Bureau of Standards secondary stan- mance. the subject of heated discussion. (I sometimes dard, and certified by the manufacturer. r:. rn page

Big You can pay more. You can pay less. Little But you can't buy DMM a better FET VOM. You get bench -size accuracy and performance The ultimate VoltOhmyst® new, hand held, 3'A-digit VOM. It's in a with our Measures AC or DC volts. 0.05V to 1500V. class by itself. Current from 0.15mA to 1.5A Highly readable, field - effect LCD Hi- or Lo -power ohms (R X 1 to R X 1 Meg , with laut- Semi -autoranging pushbutton polarity reversal. Autopolarity Fast, accurate response band mirror - :ale Small size, battery op- meter with 3 color- erated (ac optional) coded steles, Low power consumption separate p(+; ity- indicating m_ r Built -in overload protec- tion AC or ba 1.try operation. See it at your VIZ dis- tributor WV-534A $150.00 VIZ Test Instruments Group of VIZ Mfg. Co. 335 E. Price St. See it at your VIZ distributor Phila. PA 19144 VIZ Test Instruments Group Forme WD-751.A of VIZ Mfg. Co. r Formerly VIZ VIZ 335 E. Price St. 672 t A / Instruments truments $150.00 6643 A Phila. PA 19144

CIRCLE 68 ON FREE INFORMATION CARD

www.americanradiohistory.com For my car I was able to simply replace the The manufacturer states that the antenna existing antenna with the new one. In some can be mounted on either the front or the rear models this may not be possible. The problem of the car. I mounted it on the front simply is the 14 -inch long antenna housing that must because it was more convenient for me. The go under the fender. So in some instances, the unused rear -mount cable was just added to my original antenna position is not the place for stock of electronics supplies for future use. the MA -30. But aside from this, mounting and Once installed (the antenna comes with a hookup is easy and goes quickly. tunable coupler, front and rear mount cable, The MA -30 is equipped with a built -in wiring harness, hardware, wrench, and in- safety relay that prevents damage or burnout structions), hooked up to the CB and radio, to CB output transistors by allowing the CB to and coupler tuned and radios adjusted, it operate only when the antenna is at the correct really became the problem solver the package height (fully extended) for proper SWR. promised. There is a manual switch that adjusts antenna AM and FM reception were just as good as height for optimum AM /FM reception as well they had been with the factory installed anten- as a signal -splitting coupler with fine -tuning na that came with the car. That includes FM capabilities. For CB operation, a loading coil stereo too. CB was just as good as it was with CIRCLE 78 ON FREE INFORMATION CARD is provided at the top of the antenna. the magnetic roof mount I used to use. The only difference I could detect was some slight falloff on the top three channels 38- 39 -40, but it was so slight that it could have been my PHILIPS imagination. Besides, being able to completely PHILIPS retract that antenna and not having to open the trunk to dump the magnetic roof mount was worth it. R -E +( PRECISION I Sencore TF46 Super HICKOK Cricket Transistor And LEADER FET Tester Non -Linear Systems FLUKE =DATA PRECISION EC)) TRIPLETT VIZ iñc`ñ =0=CONTINENTAL SPECIALTIES CORPORATION

CIRCLE 108 ON FREE INFORMATION CARD SENCORE'S CRICKET TRANSISTOR TESTERS ARE familiar to us. The original was introduced FREE quite a while ago, and it's still around. The VOM latest in the line is the model TF46 Super Cricket made by Sencore, 3200 Sencore Drive, Purchase $400, or more and Sioux Falls, SD 57107. receive FREE this 20, 000 ohm The basic is simple: The transistor is per volt Multimeter complete circuit with test leads, battery, and hooked up as a common -emitter low- voltage carrying case. amplifier. Then, a signal is applied, and a special selector switch changes the leads to all Offer expires January 31,1978 of the possible combinations. When the cor- rect combination is selected, the transistor amplifies and inverts the signal. A phase detector then opens a circuit that allows the signal through to the speaker, with a simulta- neous readout on the meter. Since practically all bipolar transistors will operate with the collector and emitter re- versed, two selector-switch positions give a reading. To identify the correct reading, press We give you immediate off the shelf delivery on Oscilloscopes, Power Supplies, Audio & R.F. Generators, Digital Multimeters, Frequency Counters, Logic Probes, Tube & Transistor Testers, Wow & Flutter Meters, Distortion the GAIN pushbutton. One position will show a Analyzers, Bridges, and Accessories. For more information call us Toll Free: 800- 223 -0474. very low reading, the other indicates a much higher reading. The selector- switch position 212 -687 -2224 THE TEST EQUIPMENT SPECIALISTS that gives the high reading is correct and this TOLL FREE HOT LINE also gives a beta reading of the transistor. -223 -0474 ADVA The selector switch has 12 positions: six 54 West 45 Street New York. N.Y.10036 positions on the left -hand side are for NPN LEC800 il and six on the right are for PNP. The dial is www.americanradiohistory.com labelled in various combinations of RGY to 2.500 µA for bipolar transistors (upper scale) leakage at all. If it is leaky, both will show match the three red, green and yellow test and 0 to 50 mA for lam, readings of FET's. In high leakage. leads. The pointer is marked EBC: when the the correct "test" position, you read Icy, one of To determine whether you are t. :sting a right switch positions give you a reading, it the critical leakages. By moving the switch to bipolar transistor or a FET, run the lead -iden- shows the transistor is good and the leads are the remaining five positions, you can read all tification and gain test. If the GAI:q check connected to the elements shown. the other important leakage paths by pushing shows a reading of one high and one low the The model TF46 Super Cricket has an the LEAKAGE button! A chart in the model transistor is bipolar. If both positions of the audible readout of the 2 -kHz tone used for the TF46 manual shows this. I checked my collec- selector switch show exactly the sa ne gain test signal. It also has a good -sized meter for tion of bad transistors, and the results came reading, it is a FET. Source and drain can be testing bipolar and FET transistor gain, etc., out exactly right. (A1 times, I believe that I reversed on practically all FET's. and for leakage readings, which should be have more bad transistors in stock than good The model TF46 is powered by six AA made out -of- circuit for accuracy.The three ones!) batteries for portability. For bench cork, the test leads use handy color -coded miniature For diode testing, connect the red and green model PA202 AC Power Adaptor can be clips that can be connected to most transistors leads to the diode and set the switch to the two plugged into the back. This is helpful if NiCad in- circuit if there is even a little bit of the leads DIODE positions on the dial; press the LEAKAGE batteries are used, since the adaçter will showing. You can use a special three -pin probe pushbutton. A good diode will read high one recharge them so that the instrument is always hooked to the three clips to make in- circuit way and low the other. The color of the leads ready to go into the field. tests on the foil side of PC boards. The three indicates the cathode, which is very useful for The model TF46 has a special circuit that pins are also color coded and very sharp to identifying the invisible glass diodes. ends your worries about leaving it on all night penetrate any board coatings. The unit can also be used for matching (or, in my case, over the weekend!). V1 hen you The two banks of four pushbutton switches dual -diode units, which can be valuable in sets turn it on, a timer circuit starts; after it is on do not have to be used for the good /bad and with AFC, ACC, killer, demodulator and sim- for 10 minutes, it turns itself offl Just ,ush the lead- identification tests. After the reading, ilar problems. ON /OFF switch to reactivate it. When the AC just leave the transistor hooked up; you can do In checking FET's of all types, pushbuttons Power Adapter is used, this circui. is dis- everything else by switching. You can verify select either junction FET's or enhancement abled. the correct hookup by simply pushing the GAIN FET's. Dual -gate transistors can also be A 250 -page Transistor Referen -e Book is pushbutton. The right position will show a checked. All the possible FET leakages can be also available, listing over 25,000 tr in ;istors; a higher reading. In a typical test, the reversed read using the method just descrbed. Trans - special FET section appears in the )a.:k of the collector -emitter position showed a reading of conductance may be read up to 25,000 book. Cross -references to most major replace- about 3 and the right one showed a beta of Amhó s. ment transistor lines are included. --h.: listings about 75, which was correct for the general - When the unit is used to check SCR's, an show EIA and JEIA type numb( rs. basing, purpose audio transistor being tested. Two unusual reading results. A good SCR will polarity, typical gain and leakage '-slues, and pushbuttons to the left of the switch are used show a GOOD reading in one position as an whether the transistor is a signal )r a power for either signal transistors or output (power) NPN transistor, and another reading as a unit. types. good PNP transistor! To check leakage, con- A kit is available that includes mod?! TF46. Leakage can be read out -of- circuit for bipo- nect the red and green leads to the cathode and model PA202 AC Power Adapter. model lar or FET transistors. Just press the LEAKAGE anode and run the diode leakage test. If the 39G85 Touch -Test probe, and the Transistor button. The meter is calibrated from 0 to SCR does not leak, both positions will show no Reference Book. R -E The1980 Kenwoods.

The new KA -7100 integrated DC ampli- fier and KT -7500 tuner give you perfor- mance unheard of in other separate amps and tuners, as well as giving you perfor- mance and features that will remain elusive in receivers for quite a while. The KA -7100 has the lowest total har- monic distortion (0.02 %) of any integrated amp. The KT-7500 has two independent IF bands for optimum reception under any condition. By 1980, their performance will be con- sidered commonplace. Available to you now for the remarkable price of $575* for the pair.

*Nationally advertised value. Actual prices are estab- lished by Kenwood dealers. Handles optional. KENWOOD C) m For the Kenwood dealer nearest you, see your Yellow Pages, or write Kenwood, 15777 So. Broadway, Gardena, CA 9024; m

(D

27

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,1 o -orm s ehgT With you at the controls of this oscilloscope add -on, an enormous variety of seemingly three -dimensional traces can be displayed

WALTER SIKONOWIZ

How it works ANYONE WITH A NEW OSCILLOSCOPE HAS tern determines the overall shape, while observed a Lissajous figure, which is a the high - frequency figure defines the The schematic diagram of the Optical line pattern that is generated by various cross section. Synthesizer is shown on Fig. 1. Tran- harmonically related waveforms applied A great variety of complex figures can sistors QI and Q2, and associated compo- to an oscilloscope's X and Y inputs. This be generated by changing the waveforms nents comprise an astable multivibrator. article describes an Optical Synthesizer used and their phase relationships. Fur- The output of the multivibrator a ppears that uses Lissajous principles to create thermore, if the high- frequency pattern is at Q2's collector, which drive; ICI, a seemingly three -dimensional figures of amplitude -modulated by a frequency qf, CD4024BE binary ripple divider. There extraordinary beauty and intricacy. are seven synchronized, harmonically re- Front panel controls are provided that lated squarewaves that appear al IC1's vary these figures and permit the user to output pins 3, 4, 5, 6, 9, 11 and 12. Pin 12 create an enormous variety of effects. has the highest frequency signal (3840 The cost of the Optical Synthesizer is Hz), and pin 3 has the lowest f re Iuency approximately $30. signal (60 Hz). From pin 12 dowr to pin 3, signal frequencies are successively di- About the circuit vided by two. This provides a set i>f even The secret lies in summing together harmonics from which to constrict the one low- frequency and one high- frequen- Lissajous patterns. Odd harmonics can cy Lissajous figure. The low- frequency also be used, although trying to o ,tain a Lissajous figure comprises a fundamen- more complete harmonic spectrum is tal frequency f and its harmonic mf, OPTICAL SYNTHESIZER has pushbuttons and more costly. Besides, there are sufficient while the high- frequency figure is de- rotary switch to select different patterns. Two harmonics to make an excellen: Optical about the fined by frequency components of and pf. potentiometers rotate the pattern Synthesizer. vertical and horizontal axis. Here m, n and p are integers, with n and The squarewaves from ICI trust be p both much larger than m. Imagine that in which q is some small integer, the shaped into waveforms that car to used the low- frequency Lissajous figure is a cross -sectional area can be made to vary to create Lissajous patterns. Si ,t ynthe- large circle and that the high- frequency through space. To sum the two Lissajous sized waveforms are shown at pc ints A figure is a small square. When the two patterns, the two X components and the through F in Fig. 1. Triangular waves, are summed, as the electron beam rap- two Y components must be summed formed by integrating the squarewaves, idly traces small squares, it also slowly independently. These two composite sig- are available at points B, D and E. At describes a large circle, resulting in a nals are then applied to the oscilloscope's points A and C the triangular waves have "doughnut shape with a square cross X (horizontal) and Y (vertical) inputs, been clipped, but Fig. 2 shows tnat these section. The low -frequency Lissajous pat- respectively. waveforms are not only clipped but also 33

www.americanradiohistory.com +9V

R3 R4 N.C. RI Cl R2 1.5 MEG 100 K 1 C3 100K 1.5 MEG 100pF C2

14 8 10 1 toOpF 2N3904 IC1 CD4024BE

2 0101 01 2N3904 02 -9V R24 r 3 5 11 12 91K 5% CA3080 -9V

2 4 R20 R25 O3 470K 2K 1 C3 4 2N3904 5% \ 5 w 3 Y8 N.C. 5 LM308 I N.0 R30 R32 R34 4 R31 -9V 150K L 27K 39K 39K C11 3 5% R16 817 Er-P 5 5% 100pF 5% 815 1.5 3.3 D S4 R5 R9 R11 R8 Meg Meg p IC2 4 80K 3soK 820K 36K 36K 68K 51K MODULATION +9V R12 5% 5% %2 5% 5% 5% 5% j5 91K R19 2 5% 30K R23 1C10 R28 R29 R33 R10 5% 5pF 1 Meg 200K C12 IS 100K 5.6K 68K 5% 5% F R22 618 3.3K -C9 6.8 K T = 1 .005 R26 R27 DI 02 C5 03 04 5% 68K T6 22052 47052 14F .47 .33 i 5% 1µF R21 -9V 9V 5K e A C13 D1.06-1N914 S2-a 1135 CC ^O 250K .33 S3-a G NOTE: B-o-O MODULATION SELECTOR 54 Sl-a D+-0 POS. 1 -60 Hz TRIANGLE OUT 1 2 -120 Hz TRIANGLE A I REVERSE- (TO H 3 -240 Hz TRIANGEE VERT NO RMAL 4 -120 Hz RAMP BATT I T 9V ° A SHAPE I AMPL) MIXER 2 5 -OC I I C15 II C17 .1 (VERT MIXER) I 220/16V 7 R36 153-11 8 33 8 I --6 p 250 K C BATT 2 T 9v 4^ C16 C18 52-b D -07 p OUT2 1 I 22220/16V1 T.1 1/ MIXER 1 l , ITO HORIZ IHORIZ MIXER) S1-b D6 I O AMPLI FIG. 1- OPTICAL SYNTHESIZER uses oscillators, mixers, waveshaping and phase shifting techniques.

PARTS LIST

All resistors are Yl -watt, 10 %, unless R25- 2,000 -ohm trimmer C9 -.005 -ALF, paper or Mylar noted. R26 -220 ohms C10 -5 pF, polystyrene R1, R4, R23- 100,000 ohms R27 -470 ohms C12 -.01 µF, polystyrene R2, R3, R16 -1.5 megohms, 5% R28 -1 megohm C15, C16 -220 AF, 16 -volt, electrolytic R5, R8- 36,000 ohms, 5% R29- 200,000 -ohm trimmer D1-D6-1N914 diode R6, R7, R9, R10- 68,000 ohms, 5% R30- 150,000 ohms Q 1- Q3- 2N3904 R11- 51,000 ohms, 5% R31, R34- 39,000 ohms, 5% IC1- CD4024BE ripple divider R12, R24- 91,000 ohms, 5% R32- 27,000 ohms, 5% IC2 -LM308 op -amp R13- 180,000 ohms, 5% R33 -5,600 ohms, 5% IC3- CA3080 op -amp R14- 390,000 ohms, 5% R35, R36- 250,000 -ohm linear J1, J2 -BNC or binding -post output jacks R15- 820,000 ohms, 5% potentiometer S1 -DPST toggle R17 -3.3 megohms, 5% Cl, C2, C11 -100 pF, polystyrene S2- double -pole 8 position, rotary or R18 -3,300 ohms, 5% C3, C17, C18 -0.2 ALF, ceramic pushbutton R19- 30,000 ohms, 5% C4, C5 -1.0 ALF, paper or Mylar, 10% S3 -DPDT toggle R20- 470,000 ohms, 5% C6, C7 -0.47 ptF, paper or Mylar, 10% S4- single -pole 5 position rotary R21- 5,000 -ohm trimmer C8, C13, C14 -0.33 MF, paper or Mylar, BATT 1, BATT 2 -9-volt transistor R22 -6,800 ohms 10% batteries

WAVEFORM TABLE phase- shifted. Finally, there is a digitally is generated by amplitude- modulating synthesized staircase waveform at point the 3840 -Hz squarewave (ICI pin 12). F. This squarewave signal is fed via R24, The low- frequency Lissajous patterns R25 and R26 to input pin 2 of IC3, which discussed earlier will have waveforms A, is a CA3080 operational amplifier. The B, C and D as the X and Y components. gain of lC3 is a function of the current For example, if waveform A is used as passing through R30 into pin 5; this the X component and waveform B is used current is, in turn, a function of the as the Y component, plotting the result voltage at output pin 6 of IC2, which is on a piece of paper would show the Lissa- connected as a noninverting feedback jous figure to be a parallelogram. Other amplifier. Operational amplifier IC2 is combinations of A, B, C and D yield an LM308 chosen because of its low - more complex and unusual images. supply current drain. The modulating Only one high- frequency Lissajous fig- FIG 2 -PHASE RELAT ONSHIPS between the signals, routed to the input of IC2, con- ure is used in the synthesizer. This figure 60-Hz signals at circuit points A and B. sist of triangular waveforms B, D and E;

www.americanradiohistory.com selector, chooses various low -frequency waveform combinations, and switch S3 reverses the high- frequency signJ_I con- nections. Output jacks J1 and J:! must feed high- impedance loads (1 clog ohm or greater) for proper mixing ac :ion, and although J1 connects to the vertical scope channel and J2 connects to the horizontal scope channel, the connections to the scope can be reversed. When the mixers are terminated with a high-impedance

load, each output is the weighted 2- verage of the two input signals. All such input signals (waveforms A through GI have the same nominal 1.2 -volt peak -to -peak magnitude. Therefore, the peak -io -peak output of each mixer remains a constant 1.2 volts as each potentiometer is rotated. This means that the area occupiec by the display on the oscilloscope se-een also remains constant, regardless of Ifni;er set- tings. Two 9 -volt transistor batteries power the circuit. Diodes D5 and D6 protect against incorrect battery installation and, at the same time, slightly redt.ce the supply voltage since fresh 9 -volt batteries may actually supply 10 volts. The diodes insure that the maximum supp y voltage limit of ICI is never exceeded, even with fresh batteries. Capacitors C if and C16 provide a low- frequency supply bypass, and capacitors C17 and C18 provide high- frequency bypassing. Construction It is relatively easy to build the Optical Synthesizer, but you must be careful because any errors will be visible on the display. The safest procedure iiso use a printed- circuit boarb. The foil pa ttern is shown in Fig. 3 and the componer t place- ment diagram is shown in Fig. 4. If you use a printed circuit board, it is FIG. 3 -FOIL PATTERN of single -sided board shown full -size. don't important that you follow tie layout staircase waveform F; and fixed DC shown in Fig. 4 as closely as possible. potential 1. A socket should be installed for ICI, An amplitude- modulated squarewave which, since it is a CMOS unit. should be appears at output pin 3 of IC3. When installed only after all soldering is com- switch S4 selects the DC voltage from pleted. Furthermore, be sure t o use a point I. IC3's output will be a squarewave CD4024BE for ICI; devices with an of constant amplitude, i.e., unmodulated. "AE" suffix cannot supply enot gh out- Resistors R28 and R29 cancel IC3's put current. Install capacitor C10 as input offset voltage. Capacitor C11, con- close as possible to 1C2. Although most nected across R31, lengthens the tran- components mount on the PC board, sition times of the modulated squarewave capacitors C13 and C14 are w red point - in order to improve the display. In addi- to- point. tion to being part of IC3's load, resistor Pay attention to polarities for all IC's, R31 supplies bias current to emitter transistors and diodes as well as electro- follower Q3. Transistor Q3 is necessary lytic capacitors C15 and C16. In addi- imped- tion, do not confuse IC2 with C3; the to reduce IC3's very high output REAR VIEW OF FRONT PANEL shows pushbut- is a ance. tons, switches and potentiometers. Battery former is an LM308, and the o her The load for transistor Q3 consists of holder is formed from an aluminum strap. CA3080. For best results use 5%- toler- R32, R33, R34 and C12. An amplitude - ance resistors and 5% polystyrene capaci- modulated, slightly rounded squarewave Now, all that remains is the summa- tors where specified. is available at point G, and at point H tion of the low- frequency and high - The front panel layout is not critical. there is an amplitude- modulated trian- frequency Lissajous patterns. The Y Switch S2 in the prototype was a push- gular waveform. If modulation is con- components of the two figures are mixed button unit that happened to be around stant and if points G and H are connected in R35, while the X components are at the time of construction. You can just to the X and Y inputs of an oscilloscope, summed in R36. Capacitors C13 and as well use a rotary switch that W ill prob- a rectangle with two rounded corners C14 block the DC supply so that only AC ably be more readily available and less appeals. signals are mixed. Switch S2, the SHAPE expensive. Output jacks JI and J2 should

www.americanradiohistory.com match the oscilloscope ccnnectors. Gen- quency components produces interesting potential at point I is applied to IC2. erally, these connectors will be either and sometimes dramatic changes in the Adjust trimmer R25 so that the peak -to- BNC or binding -post types. display, depending upon the settings of peak voltage of the 3840 -Hz squarewave Make a battery holder for BATTI and the mixers and of S2. at point G is 1.2. Since the potential at BATT2 with a 16 -gauge aluminum When wiring mixer potentiometers point G is always more negative than strap, bent to fit the battery dimensions. R35 and R36, connect them so that their ground, set the vertical amplifier for a Use two fresh, high quality batteries. If actions are similar. Wire them so that DC input signal. When a 1.2 -volt peak - the battery voltages are unequal, trian- when each wiper advances fully count- to -peak signal has been obtained at point gular waveforms B, D and E will not be erclockwise, it directly contacts a low - G, check point H, where you should symmetrical with respect to ground, and frequency input. Advancing both con- observe a triangular wave of the same some signal clipping will result. While trols together in a clockwise direction magnitude. Now dial in the various mod- this sort of clipping may produce some then causes the simultaneous increase in ulating waveforms via S4, and verify that interesting visual effects, battery voltages high -frequency content of both outputs. modulation occurs at points G and H. This completes the calibration procedure and the synthesizer is ready for use. TO ROT R OF S4 R17

R6 C15 Using the synthesizer R4 R18 I R13 C16 H15 R24 c I The Optical Synthesizer is easy to use. I 2 ICI First, connect the C2 Cl Ì3 outputs to the X and Y C scope inputs. After the scope has warmed Q10.-8 I I 8-( )Q2 -R14-

E E -R13- -RB- up, center the dot on the screen. If you R19 -R12- 026 wish, remove the scope's graticule, as it R5 I O 0 R6 can be distracting. IC3 Set modulation selector S4 so that the I -R27- RI8 I -028- IC2 input connects to point I. Turn both mixing potentiometers fully count- C4 erclockwise so that their wipers directly -ß31- contact low- frequency inputs A, B, C or -618- O C B-C11- -033- -R32- Q3 D. Now apply power to the synthesizer, E and -C12 R34 adjust the scope's X and Y sensitivity 0114 R7 D2 06 05 controls so that the image fills the oscil- *414- I -4+- I loscope screen. Use the focus and astigmatism controls

NOTE on the oscilloscope to obtain a sharp I si-b si-a PADS LABELLED AO THROUGH® CONNECT TO S2, S3 & 54 display over the entire screen. Use all (AS SHOWN IN SCHEMATIC) BATT 2 eight / BATT 1 / positions of shape -selector switch / ON-OFF J S2 to obtain the four low -frequency Lis - FIG. 4- COMPONENT PLACEMENT diagram for the PC board. sajous patterns plus their four reversed counterparts. Set S2 so that there is a parallelogram should be as equal as possible when the Of course, the controls will usually be on the screen, and rotate the scope's initial adjustments are made on the syn- manipulated independently, but they are intensity control to maximum. Advance thesizer. easier to correlate if the actions have a both mixers, stopping when you have Note how switch S2 is wired. One posi- similar effect. some degree of three -dimensionality in tion of the switch may send waveform the display. Next, dial in the various signal A to the vertical mixer and wave- Calibration modulating waveforms via switch S4 to form signal B to the horizontal mixer, but After construction is complete, install notice the effects. You can now experi- the next switch position will reverse these ICI and apply power. Use your oscillo- ment with the rest of the controls to note connections. Such a connection reversal scope to verify waveform signals A their effect on the display. results in an image reversal on the screen. through F, which should all have a peak - The mixers are the most important This doubles the number of possible to -peak amplitude of about 1.2 volts. controls on the synthesizer, and careful displays. By means of switch S3, the Now, adjust S4 so that the 60 -Hz trian- mixing will yield many fascinating dis- high- frequency mixer inputs can also be gle waveform B is applied to 1C2. Attach plays. The visual effects include a change reversed. Interchanging the high -fre- a probe to 1C2 output pin 6 and adjust in the size relationships between various trimmer R21 for the largest possible parts of an image plus apparent rotations unclipped triangular waveform, which about two axes. As a display rotates, will have an amplitude of around 15 volts certain lines may coincide, causing the peak -to -peak. display to take on a whole new character. Now, leaving S4 where it is, ground As more of the high -frequency signal is 1C3 pin 2 using a short jumper lead. mixed with the low- frequency signal, var- Attach your scope probe to IC3 output ious sections of an image overlap. Conse- pin 6 and adjust trimmer R29 to elimi- quently, the distinction between the over- nate the 60 -Hz triangular waveform. all shape of the image and the shape of You will probably be picking up some the cross section is lost as a new pattern low -level, high -frequency signals at the emerges. same time. This pickup is unavoidable When you have become familiar with and should be ignored. After the 60 -Hz the mixing procedure, you can create triangular wave has been cancelled, dis- dynamic displays that twirl and change connect the probe and remove the ground shape on the screen as the two mixers are lead from IC3 pin 2. PC BOARD is mounted vertically against rear slowly rotated. Experiment with the con- panel and held in place with stand -offs. Trim- Reconnect the scope probe to point G trols until you become familiar with their mer adjustments are easily accessible. in the circuit. Set S4 so that the DC effects. R -E

www.americanradiohistory.com Build This Test Meter

N DIG! TAL C.AyICCI TANCF MI1 rR uf OLF A I

A

M easure Capacitance On A Dìgìtal Readout Localizing troubles in electronics can be difficult when caused by off- value capacitors. This digital checker lets you pinpoint them quickly JAMES 1'E RNON

CAPACITORS ARE AMONG THE MOST com- scribed in this article can accurately A built -in overflow indicator L Is you mon components used in electronics to- measure any unknown capacitors (in- when the capacitor is too large for the day. They are also among the most diffi- cluding electrolytics) from 100 pF to scale used. You can easily mx:fy the cult parts to measure inexpensively with 1000 µF in three ranges; and it can be circuit to include four 5 -volt NiC ad AA any accuracy. Good capacitance measur- built for less than $40. Just pressing a batteries for portable operation. ing equipment is quite costly. button gives an instantaneous digital The digital capacitance meter de- reading of capacitance in microfarads. How it works The circuit shown in Fig. 1 dt.:-mines the value of the test capacitor by -easur- SPECIFICATIONS ing the time required to cl-a ge the capacitor to a predetermined 'aItage. Range 100 pF - 1000 µF in three ranges When the TEST button is pressed, one - A 100 pF - .9999 µF half of dual timer IC12 acts Is a one - B.01µF- 99.99µF shot, the 100 -kHz o cillator C0.1pF- 999.9µF activating (the other half of ICI 2) while -7e test Capacitor Voltage Rating Any value above 4 volts DC recommended. BLOCK DIAGRAM OF CIRCUIT will the with 3 or 4 (The 556 charge capacitor TEST CAPACITOR volts maximum.) 11, GICATOR IIC9 -101 OVERFLOW L;HT IN OICATOF Accuracy Depends slightly upon the quality of the inter- 0 -I-L nrinrLR nal components. M t ONE OSCILLATOR COUNTER .ISPLAy SHOT 1100 kHz) 7,, NETWORK 4" Normally ± 5%; maximum error approximately - y

7 %. IIC5 -81 101.4, ` Y CLOCK NE556 110121 ]ISPT -41 OUTPUT- I L! -sup- ONE SHOT Cost Approximately $40 (including the power TEST ply circuitry). BUTTON OSCILLATOR) LL Lan. OUTPUT JI.RfL L L_ TO COUNTER IC's Time Around two evenings. Construction DIGITAL CAPACITANCE METER FIG. 1- CAPACITANCE METER mu ai' urea the Power Requirements 117 VAC (or an optional 5 -volt NiCad pack). time required to charge a capacitor tc a prede- Drain: approximately 600 mA at 5 VDC (de- termined voltage. Waveforms show that the pending upon the size and type of the LED's pulses from the oscillator are only f,d to the used). counter IC's when the output of the or e -shot is at a logic high level.

www.americanradiohistory.com TO 6 6 Ig TO TO TO 6 R40 MOST PIN'S 2, 6 SIGNIFICANT R41 R42 LEAST SIGNIFICANT 3 DIGIT VCC113 DIGIT IC10 DISP2 DISP3 VCC DISP1 VCC VCC.13 DISP4 SEGMENTS-I. F G A B C D E 2

¡SEE R5-R33 DISP1 33052

9 16 VCC VCCfl6 VCC16-

ICI IC3 IC4 7447 7447 7447

6 7 1 2 8

11 12 1 9 8 10

IC5 7490

5 21 31141 5 2j-J3 14

VCC R39 3301 2 VCC H 040 33052 VCCfI Cl 14 14 13 12 9 8 6 14 .01 12

I\ 2 11 IC9 IC10 IC11 IC12 7430 7400 74121 556 I(- 3 4 5 6 2 1111 C2 J 312111 11 5 if 8 1 12 13 _. e_6_1 .01 - 041 J1 33052

Bp12 J2

C3 TEST TO 01 = CAPACITOR PIN 9 DISP 4

52-5

R4 VCC 1K R42 R43 R44 R2 33052 33052 100K 33052 VCC

TO DISP1 TO PIN 6 TO DISP3 OISP4 PIN PIN 6 6

FIG. 2- CAPACITOR UNDER TEST is charged to Vcc through resistor selected by range switch S2 -a. Overrange condition is indicated by the right -hand decimal point of the least- significant digit of the display.

PARTS LIST All resistors '/z watt, 10 %, unless noted. IC5 -1C8- 7490 - decade counter T1- 12-volt, 1.2 -amp transformer (Radio R1, R3- 10,000 -ohm, 23 -turn trimmer, 5% 1C9- 7430 -8 -input NAND gate Shack No. 273 -1505, or equal) (Fairchild) IC10- 7400 -2 -input quad NAND gate RECT1 -4 -amp, 50 -volt, PIV bridge R2- 100,000 -ohm, 23 -turn trimmer, 5% IC11- 74121 - monostable multivibrator rectifier (Fairchild) (one -shot) DSP1- DSP4 -.3 -inch, common -anode, 7- R4- 1000-ohm, 23 -turn trimmer, 5% IC12- 556 -dual timer segment LED display (Radio Shack No. (Fairchild) IC13- LM309K, 5 -volt regulator 276 -053, or equal) R5 -R44 -330 ohms J1, J2- banana jacks Misc. -metal cabinet, 6'/4 X 21/4 X 7'/4- R45 -1000 ohms, 5% S1- momentary pushbutton SPST switch, inches (Radio Shack); hardware; line Cl, C2 -.01 µF, mica, 5% normally open (Radio Shack No. 275- cord; banana plugs and clip leads; C3- .001 µF, mica, 5% 618, or equal) optional heat sink for voltage regulator C4, C5 -1000 µF, 16-volt, electrolytic S2 -2 -pole, 3- position rotary switch IC. IC1 -1C4- 7447 -7- segment LED driver S3 -SPST toggle switch

capacitor begins to charge. These 100 -Hz display the total count. This provides an range of the meter in three steps from pulses from ICI 2 are counted and dis- almost instantaneous capacitance display 100 pF to 1000 µF, while switch S2 -b played on the digital readout. Once the that is accurate to four decimal places. changes the position of the decimal point test capacitor is charged, the output of Switch SI, shown in Fig. 2, activates for a direct readout. Integrated circuits the one -shot drops low, causing ICI2 to the pulsing oscillator and the one -shot IC9 and ICIO detect a counter overflow stop pulsing and the digital readout to multivibrator. Switch 52 -a changes the and display the "overflow message" by

www.americanradiohistory.com REGT 1 IC13 12 T1 .O+JCC lighting up the fourth -digit left -hand dec- LM-309K imal point. One -shot IC11 shortens the _r.a I C5 pulse from SI to 40 ns for better relia- 1000: F 7. 1000µ F bility within the given test cycle. The 16V 16V power supply (see the circuit shown in 1 Fig. 3) provides enough current to power the capacitance meter. 1 INPUT / 2 OUTPUT 1\\ BOTT (GROUND) Build your own VIEW -CASE The entire circuit, including the power OF IC13 \Q 3 supply, can be built on a 61/4 X 41/2-inch FIG. 3 -POWER SUPPLY for capacitance meter. NiCad batteries can also be used for pwtable piece of perforated board. While parts operation. is not critical, you may wish to placement PARTS LAYOUT FOR CAPACITANCE DIGITAL METER 2 53 follow the design shown in Fig. 4. Be sure 4 DIGIT DISPLAY HOLDER Si to orient each IC correctly before insert- ing it into the circuit. The prototype was 4 assembled in a 61/4 X 23/4 X 71/3 -inch R42, R43, R44 metal cabinet with a four -digit LLD ...,.;... holes the holder in the front. Drill for F5TDR38 display, line cord, all switches, optional heat sink and test button. The front LEADS FROM binding posts are polarized (red is posi- R2, R3, R4 tive; black is negative) so that electro- lytics and other polarized capacitors can be tested easily. Run the power cord for 64 : the capacitance meter through a hole in

the back of the cabinet with a strain C1 relief. 1C12 C Wire -wrap IC sockets are very helpful during circuit construction. Although ...... aC3 these sockets may cost a little more than C2 standard solder sockets, they are worth RI the extra expense. All the IC's used in the 112 capacitance meter are simple hobby com- RECT 1 C5 ponents that can be purchased from most : R4 local electronics parts stores. Resistors and capacitors should be ± 5% tolerance for better meter accuracy. Keep the wir- ing as short as possible (especially the external test leads from ICI 2) to prevent any stray capacitance from being picked up. No problems were encountered dur- ing construction. Because the inexpensive pushbutton LINE CORD switch selected for the prototype meter INPUT IC13 OUTPUT gave many varied readings for a given capacitor, replacing switch SI with a better switch significantly increased reading accuracy and repeatability. Ac- FIG. 4- PERFORATED BOARD and wire- wrapping was used to build the prototype. tual circuit wiring took about two evenings and considerable time was spent The v;.lue of carefully checking each pin against the The meter is now calibrated and ready to tion A, press the test button. schematic for correct connections. use. the unknown capacitor will immediately be displayed in microfarads. If the over- Calibration Measuring capacitors flow light goes on, change to 'h+: next test This Use an ohmmeter to preset RI (as (Before testing an electrolytic that's higher range position and again. range is closely as possible) to 6715 ohms. (Note: been on the shelf or unused for several procedure insures that the right once RI is set, it does not have to be months, give it a quick ohmmeter check. used for any size capacitor. adjusted again.) Preset R2 to 90,900 But before you do, it is best to make sure When testing an electrolytic caplcitor, ohms, R3 to 9090 ohms and R4 to 910 the capacitor is discharged by shorting it. discharge it completely by shorting the muer to ohms. Place a capacitor with a known Then connect the ohmmeter test leads leads before connecting it to the value (5% or better) between the termi- and watch for the needle to fly over to prevent any circuit damage. A s sorted nals, and, with the range switch set in zero and then slowly rise and stabilize at capacitor activates the overflow lig -it and A position A (100 pF -1 µF), adjust R2 for a point up- scale. This is a rough indica- all 8's should appear on the disp ay. an accurate readout when switch SI is tion of the capacitor's ability to hold a capacitor of less than 100 pF stil indi- pressed. Follow the same procedure (us- charge. If the needle stays on zero, the cates .0001 µF on the lowest scale. When ing larger capacitors) for range -switch capacitor is shorted -- Editor) the meter is first turned on, a rc ndom be displayed. Eacl time position B (.01 µF-100 pF) and range - The actual operation of the digital number may switch position C (0.1 p.F -1000 MF). A capacitance meter is straightforward. switch SI is pressed, the counters are midrange capacitor calibrates the scale Connect an unknown capacitor to banana automatically reset to zero, which clears quite well. With quality components, the jacks J1 and J2 (with correct polarity, if the initial display and charges tte test meter has an accuracy of ± 5% to 7 %. known) and with switch S2 -a set to posi- capacitor for a new reading. R -E 39

www.americanradiohistory.com Build CB Switcher for Music Between Calls CB radio and some other form of radio or entertainment audio are common in todays cars. This electronic switch lets you enjoy both while driving safely

GEORGE SANTE

ON THE ROAD TODAY, YOU HAVE A CHOICE turn down the radio volume before key- muted and the CB radio takes over. Press of listening to the car radio or tape player ing the mike. All this distracts from your the push -to -talk button on the mike and or monitoring a CB channel. It is hard to driving and can lead to an accident or a the radio quiets as the transmission be- do both simultaneously with any degree hazardous situation. gins. Release the pushbutton and you'll of satisfaction. When the car radio is For safer driving and CB operating hear the radio if there is no reply to your turned up to a comfortable level, its convenience, add this automatic CB call. volume may make you miss a weak, but Switcher to the equipment in your car. It important, CB transmission. If you turn lets you listen to the car radio or tapes The circuit up the CB volume and set the squelch for and insures that you won't miss a weak The CB Switcher is basically an elec- weak -signal reception, the radio will be CB call because of the radio's high tronic -relay switching system that is ac- drowned out by the almost continuous volume. If you want to transmit, you tuated by either the RF output from your roar from the CB speaker. Also, if you don't have to turn down the radio. When CB rig or the AF output from its speaker want to make a transmission, you must a CB signal is received, the car radio is terminals. When the relays are ener-

PARTS LIST All resistors '/4 watt, 5 %, unless noted. D1, D2- 1N4001 The following parts are available from R1,R2,R3,R4 -10 ohms, 1 watt D3, D4 -1N914 Guardsman Electronics, Box 215, R5 -1 megohm Q1- 2N4124 Brooklyn, NY 11207. R6- 10,000 ohms 02-2N4126 Printed -circuit board, $3.00 postage R7 -3300 ohms RFC1 -56 AH, RF choke paid. R8 -1000 ohms RY1, RY2 -12 VDC relay, 320 ohms, DPDT Set of 2 relays, $8.00 postage paid. C1 -.001 disc contacts Complete kit, including case, $14.95 C2 -.05 disc Misc. -Case, 2 -lug terminal strip, wire, postage paid. C3 -10 µF, 6 volt, electrolytic cable, coaxial connectors, hardware. Assembled unit, $29.95 postage paid.

CB R2 AUDIO MW OUT- 1052 o-12V PUT 111 1W 1052 01 = 1N4001 R3 RADIO I 1W 1052 1W R6 10K 07 3.3K (12 2N4126 a RFC1 ° 5004 CB SPKR 1 TRANSCEIVER IY----.0 RY1 ",A--0-111 32012 , O

I021N4001 C2 .05µF

RY2 I

3200 SPKR 2

.001µF 04 Of O I 2N4124 1N914 03 = 1N914 C3 ` R5 WAIFT 1 Meg IR4 102 RADIO 2 6V 1W o t

FIG. 1 -CB SWITCHER has provisions for two speakers to switch a stereo signal source.

www.americanradiohistory.com gized, the car speakers are automatically disconnected from the radio snil tape player and are switched across tYc output of the CB receiver. The schematic is shown in Fig. I. The antenna transmission line and a short length of coaxial cable from the CB transceiver are joined to connccurs at opposite ends of the switcher caso. kudio output from the CB remote sp:a ker or PA speaker is fed into the ;a itcher through a length of speaker -type audio cable. Similar leads connect the ;u itcher relay terminals to the radio and tape - player outputs and their respective peak- ers in the car. The radio and tape -player spec kt -s are connected directly to their akers through the normally closed conta_ts on CB SWITCHER mounts in a 1'/: X 1' /, X 5 -inch case. All connections to the CB switcher, except the a CB Nall is two coaxial connections, are made via wires fed through grommets in the side of the case. relays RY1 and RY2. When received, a portion of the audio ;ii nal is rectified by D3 and D4 to develop .t DC control voltage that is applied to Q and Q2 to energize the relays. W ier the relays pull in, the car speaker- are switched to the CB receiver. Sim iarly, when you press the mike button to .rans- mit, a portion of the RF is rectified iy D3 tcelt:p1.° and D4, again energizing the rß_11 ys to fr-NSop mute the car radio. Construction The switcher is simple and easy to build. Its handful of parts moult on a r single -sided PC board. The foil patl.rn is shown in Fig. 2 and Fig. 3 shour the FIG. 2 -FCIL PATTERN of PC board shown full size. component layout. The switche when supplied as a complete kit, corr (.., in a metal case, l' /2 -inch square and t'- i-ches i12v D -t- I - long. Coaxial cable fittings are 3- the I D2 C connecting leads are or ,ught RFC 1 132 ends, and RY1 RY2 11,7 C2 R6 out through grommeted holes on rear of the case, as shown in Fig. 4. 404 RI 02 I8 CI When all parts have been mount Ad on 3 CB OUT the PC board and you are ready tu mount CI R5 R3 R4 R1 it in the case, solder on the connecting 03 ANT 0I GNO cables and run them through the correct I e \SPKR \PKR 2 holes in the rear of the case. Be St re to RADIO I RADIO 2 install the board with the corn )o -ents FIG. 3- COMPONENT LAYOUT. facing the inside of the case. EXTERNAL SPEAKER ANTENNA OR EARPHONE JACK INPUT Installation RG -58U JUMPER CABLE SET 1 CB C You will have to make slight madilica- PL-259 tions to the CB rig as well as to th.. car radio. (The CB radio won't need m difi- AUTO cation it has either an external ;cpcakcr RADIO if OR jack or terminals for a PA speaker. The TAPE DECK car radio modification involves onl. the RED i +12V loudspeaker connections. Disconnect the BLK 1CB GNO speakers and reconnect them thro ier the ANTENNA (12V as shown in Fig. 4. Conr ee t the RETURN) switcher, switcher 12 -volt power lead to a stitched 12 -volt point in the CB rig so Cu. the switcher is on only when the CB i; cm. co i ácc With the CB squelch properly ;e1 and ANTENNA TRANSCEIVER with both the CB set and car radio tt. -ned PL-259 on, you should hear the car radio or y- until a CB signal comes in. Now, :i_ car radio is quiet and the CB transmi.z! ,n is o o heard through the CB speaker aN the radio speaker. Pressing the mi Out- FIG. 4- INSTALLATION of the CB Switcher is straightforward. The volume control on the CB rig must car be turned high enough to trigger the CB Switcher when a call is received. ton instantly mutes the car radio. R -E 41

www.americanradiohistory.com Beyond The Basics CB TEST INSTRUMENTS

The rigid electronic standards set for CB radios make it imperative that you use test instruments that are highly accurate while being designed for speed and convenience in servicing. Here are some you should consider

FOREST BELT

THERE ARE MANY INSTRUMENTS NOT most, is produced by Lectrotech. The ther mike or audio stages. mentioned in the November 1977 issue of model CB -40 Chanalyst contains an RF Separate meters measure the audio Radio -Electronics in the special section wattmeter for AM (average -reading) or output power from the receiver. Remem- on basic CB test instruments. You may SSB (peak -reading) transmitter outputs. ber, for a 10 -dB signal -plus- noise /noise wonder why they were omitted. Aren't While power readings are part of any CB (S + N /N) sensitivity measurement, they any good; don't you need them; and test set, not all can read on peaks so that you must arrange, with an RF signal if they're not basic instruments, what are you can measure SSB power. generator, a 10:1 power ratio (10 dB) they? A reversing switch sets up the instru- between audio- signal -plus -noise and Many of these other test instruments ment for VSWR ( Voltage Standing - noise -alone at the receiver speaker. The are highly useful and can save you much Wave Ratio) measurements. Some test audio power meter has a dB scale to help time and money. Some are specialized. sets require converting reflected power you recognize the 10:1 power ratio. They speed repairs and testing, and make into VSWR; a scale on the model CB -40 The model CB -40 contains RF connec- particular jobs easier. Many instruments power meter handles that automatically. tions for a frequency counter and RF perform tasks or measurements you need This unique instrument offers a ready - generator. This interface comes in handy only occasionally. However, do not over- made alternative to building a bench -test for bench work. Connect one coaxial look them because they are very useful panel. Radio frequency metering takes cable from the model CB -40 to the trans- when you do need them. place across an internal 52 -ohm dummy ceiver. The RF generator sends a signal Others are general- purpose instru- load. A simple modulation scope parallels ments, such as communications test sets the RF- output metering. Thus, you can for CB and other communications gear. examine RF for unwanted oscillations Their chief attractions usually are their and for modulation quality. low cost, portability and, sometimes, ver- A switch selects either a sinusoidal or a satility. Do not arbitrarily equate low trapezoidal modulation display. Old cost with low quality; it may not be so. communications hands, especially hams, Consider these other instruments in use trapezoidal modulation displays be- your quest for the ideal CB servicing cause they are easy to set up with a low - setup because each has its distinctive cost oscilloscope. The model CB -40 lets usefulness. You should know what these you select whichever display you prefer. instruments are and how they can help The modulation scope sync is internal you make more money in your service and automatic if you modulate the trans- INDIVIDUAL METERS FOR EACH FUNCTION operation, either at the bench or on the mitter by holding its microphone near the characterize Communications Power, Inc. road. small- speaker tone source. An audio gen- transmitter tester. erator- either a single-tone or a two -tone CB test sets generator for SSB -sends a signal to a to the transceiver. When you key the CB test sets range from inexpensive small speaker on the top panel. The transmitter, the RF output switches the units to more elaborate instruments. You signal also appears at banana jacks on model CB -40 to its transmit mode. Con- should see various test sets before decid- the front, to modulate the transmitter nections are made automatically to an ing which features could be most helpful directly instead of acoustically through external frequency counter, and to the on the bench or in service calls. the mike. This feature is important also RF power meter and modulation scope One unit, slightly more elaborate than for signal -injection troubleshooting in ei- inside the model CB -40. 42

www.americanradiohistory.com Other manufacturers produce multi- readings against dependable, accurate function CB test sets. Most are better equipment. After all, you must be able to termed transmitter test sets. For exam- depend on what your instruments tell ple, the Communications Power, Inc. you. An instrument you can't trust is worse than no instrument at all.

FIRST DIGITAL POWER METER was added to SOLID -STATE DIP METER from Heath can be an in -line frequency counter in this Hickok built in one evening. Lets you test tun. ag and instrument. Also includes automatic VSWR resonance in circuits not even undar power. sensing, with display in digital numerals. Acts as tunable absorption wavemete t.: check harmonics from transmitters, oscilleta's, and the like. model W411000 meter contains a watt- meter (for both average and peak mea- signed their own station equipment use surements), a VSWR meter and a modu- TRANSMITTER TESTER from Simpson Electric grid -dip meters, or their modern solid - lation meter. Each function has its own adds a relative field- strength meter to useful- state counterparts. CB technicia -s are ness. Helps with antenna tuning problems. Unit to this design are seldom familiar with these instnur lents. separate meter. Similar also has power, VSWR, and modulation mea- the Para Dynamics model PDC550 and surements. In its ordinary mode, a dip me er can model PDC600; the former is the smaller test the resonance of a tuned circuit and more portable of the two units. Simpson, a manufacturer of high -qual- without any direct connection, : n f with- ity multimeters, offers the model 440 out power being applied to 11.: :ircuit. Communications Tester. This instru- The dip meter contains an oscil. a or and ment is a transmitter tester. One meter another meter to measure oscifilai 7r cur- shows RF power; another meter lets you rent. When the dip -meter coi held read either the VSWR or modulation near a circuit that is tuned to el 7ly the percentage simultaneously. same frequency as the meter c Ilator, inductive coupling loads -down 2 dip - Field- strength meters meter oscillator, causing a redm..ion or The Simpson model 440 also contains dip in the current reading. a field -strength meter, labeled RFS (Rel- Here's one application. Tun -.: he dip ative Field Strength). The meter read- meter as accurately as possible o 27.185

AUTOMATIC a telescoping (use a frenquency count'. r . Place PERFORMANCE ings are not absolute. Raise MHz CB TESTER antenna and place the meter near enough the dip -meter coil near a CH : ntenna to the transmitter antenna for a useful loading coil. Tune the antenna step -by- reading. If you move the model 440, the step, as usual. At resonance, the ntenna reading changes. absorbs energy from the ins,.rnment's This function proves highly useful at oscillator and pulls the mete;- -eading times. Occasionally an antenna simply downward. will not respond to ordinary minimum A dip meter can also act as an absorp- VSWR tuning. Set the field -strength me- tion wavemeter. Its action is >inuilar to ter near the antenna and do not move it. that of a field- strength meter, esa:pt that Then, tune the antenna step -by -step for the wavemeter is tunable. maximum radiated signal as shown by So, suppose you tune the dip instru- the field- strength meter. If the reading ment to 54 MHz and place tEe ciil near AUTOMATIC VSWR SENSING was pioneered in goes too high, shorten the telescoping the dummy load of a transmitter on the this Sencore instrument. antenna on the meter. You always mea- bench. Key the transmitter an I_ne the sure relative signal strength. A CB an- TVI filter for a minimum readin ;. on the Hickok has a unique tester that's a tenna or any other communications dip instrument. It is impossiblbe o mea- digital frequency counter that can be antenna radiates the most signal (the sure the amount of second- harm)(lic re- hooked in -line with the CB antenna strongest electromagnetic field) when its duction this way, but the method assures cable. A switch on the model 38 lets you length is exactly at resonance. Do not use that you have tuned the trap for a correct measure RF power (peak or average) and a field- .strength meter to tune up a trans- minimum. displays watts digitally. Another switch mitter. Use an in -line wattmeter con- position lets the instrument measure the nected to a dummy load, never to an Audio voltmeters VSWR, showing the radio digitally. An- antenna. An audio voltmeter features h gh sen- other version, the Hickok model 388, also Several low -cost testers include a field - sitivity- usually fractions of t, millivolt

measures modulation percentage. strength meter. It's easy to add to a RMS on a 1 -mV range full scat:. More The Sencore model CB41 uses push- simple wattmeter, if the meter movement important, its frequency response extends buttons to test RF and SSB power, is sensitive enough. Just a diode, a capac- the reading accuracy to from 20 Hz to I VSWR and modulation percentage. itor and a piece of wire for sensing are MHz or more. (The AC ranges of an Other simpler transmitter testers are needed. ordinary multimeter lose accue icy be- sold by several CB manufacturers as yond 100 or 200 Hz.) The Motorola accessories. However, insist on demon- Dip meters model S -10530 is called an AC Volt- strations, and don't hesitate to verify Ham radio operators who have de- meter, but it includes the audio v Iltmeter 43

www.americanradiohistory.com specifications described in this article. an autoranging digital- reading capaci- curve tracer (formerly the Jud Williams Because of these sensitive wideband tance meter. You read values from 0.1 pF model A). Sencore helped pioneer audi- specifications, most technicians think of to 200,000 µF on a 31/4-digit liquid - ble quick- testing with the Cricket series, an audio voltmeter in terms of hi -fi/ crystal display. Battery operation and its models TF26, TF30, TF40 and TF46. stereo testing. However, this instrument small size make the C-Meter portable. The model TF30 and the model TF46 works well in signal tracing and gain Hickok's model 370 Deluxe Multi - also measure parameters. Viz Manufac- testing in microphone stages of transmit- meter measures capacitance values from turing offers a model WT-501A tran- ters. 500 pF to 10,000µF. sistor and diode checker. The audio voltmeter can also be used Curve tracers quickly analyze the in- in receiver sensitivity measurement. A Transistor testers tegrity of transistor transfer curves. You 10:1 power ratio is similar to a 3.16:1 No one is averse to testing transistors can tell whether a component is usable by voltage ratio. Either ratio equals the 10- in- circuit since it saves time. Once a tran- the shape of the curve it produces on an dB change you need between no- modula- oscilloscope face. tion and 30- percent modulation. The test is really a matter of lines and Here's a specific procedure, using the angles. You don't care too much what the voltmeter instead of an audio wattmeter. curve angle is exactly; that depends on Feed a small amount of unmodulated transistor design. What you look for is a RF signal (about 1µV) into a receiver, distinct and sharp knee where conduction exactly on- frequency. Set the receiver begins. You should see fairly straight volume control for 500 mV of noise at the lines on either side of the angle. Any speaker ('/2 volt). Next, add 30- percent curved or twisted traces signify leakage. modulation to the RF input, using a Most curve tracers display a family of 1000 -Hz tone. Note the new reading curves on the oscilloscope screen. Just across the speaker. If the reading is less make three connections to the transistor than 1600 mV (3.16 X 500 mV), in- crease the RF input level slightly; if the reading is more than 1600 mV, reduce BMK /PRECISION CALLS THIS a lab- quality the RF input slightly. tester for measuring parameters of transistors and other semiconductor devices. lets you set It may be work necessary to back and up exact operating conditions; even inject sig- forth a time or two for an exact ratio of nals. 3.16:1 between the noise -alone reading and the noise -plus -audio reading. But sistor is removed from the circuit it can when you have accomplished that, you be tested quickly with an ohmmeter. A can then read the RF signal microvolts forward -backward test of base- emitter from the generator dial or meter. This and base- collector junctions gives a fairly reading is the 10 -dB S + N/N sensi- valid assessment of whether a transistor tivity of the receiver. can operate or not.

Readings of 1 volt and 3.16 volts work For in- circuit testing, there are many well. as It's the ratio that counts because different sizes and designs of testers. The VARIANT ON CURVE -TRACER IDEA, this Hun - the specification standard requires a 10- latest B &K /Precision catalog lists two tron Instruments device evaluates junctions dB difference. quick -test versions, the model 510 and with two -lead in- circuit test. Displays result on With an ordinary digital voltmeter, the the model 520B; the model 50 /A curve self- contained oscilloscope. accuracy may be off at 1000 Hz. Most DMM's are calibrated for 60 Hz on the and actually observe "gain' curves. AC volts scale, and errors are not linear. The Huntron Tracker tests transistors and diodes in- circuit with only two test - Capacitor testers lead connections. The results are dis- Some technicians refuse to test indi- played on a small oscilloscope contained vidual parts, except as a last resort. They in the instrument. will use a tube tester or an ohmmeter to The Tracker is not exactly a curve check a tube or resistor and most use a tracer in the usual sense. It is provided transistor tester, but they rebel at testing with a two -lead connection so that it can a single capacitor. Yet certain capacitor analyze conduction and leakage qualities faults show up most quickly on a good of one junction at a time. Just touch two capacitor tester. probes across the base- emitter or the Sprague Products Co. makes the mod- base -collector junction right in the circuit el TO -6B, Tel -Ohmike Capacitor Ana- (down to 10 ohms of shunting resis- lyzer, which is a thoroughly up -to -date tance). The display lines bend if there is instrument. The model TO -6B is basi- leakage, and the sharp knee rounds out if cally an R -C bridge, with an "eye" to the beta or alpha is poor. To determine indicate the null. This instrument mea- SENCORE TESTER TAKES ITS "CRICKET" the test- connection polarity, just touch sures capacitance from I pF to 2000µF. name from fact that instrument "chirps" to the probes across the diode or transistor Special circuits accommodate the low - indicate good transistor. Several models let you junction and watch the oscilloscope voltage capacitors found in solid -state measure parameters too. screen. equipment. You can measure the power factor of an electrolytic as well as leakage tracer for use with an oscilloscope; and Time and dollars in any capacitor. Of course, an open the model 530 parameter tester. Hickok Your criteria for judging &test instru- capacitor reads minimal capacitance. produces the model 217 and the model ment should be: (I) Will it help me do a Heath has an R -C bridge in kit form. 215 for quick checks; the model 440 better job? (2) Will it make my job Continental Specialties Corp. also pro- curve tracer; and the model 220 param- quicker and more profitable? If you can duces an R -C bridge, the model DM -3. eter tester. Lectrotech markets a model answer "yes" to either question, buy the The C- Meter, built by ECD Corp., is TT-250 quick tester and a model CT -1 instrument and learn to use it. R -E

www.americanradiohistory.com ROUNDUP Digital Clock Kits For Your Car Part 111 FRED BLECHMAN, K6UGT w-

Ì!Ì fI ! r ! i !

APPLIED MARKETING LC -101. JAMES DIGITAL AUTO CLOCK THE HEATH GC -1093 has a bright, JAMES ALARM CLOCK, w E' I set- LCD readout visible in sunlight. with under -dash bracket mount. easy -to -read display. ting and seconds switches mmi ele.1111

IN OCTOBER, WE PRESENTED AN OVER -VIEW OF THE ELECTRONIC car, at least add a 33 -ohm '/, -watt resistor and also sdd a clock kits for automobiles and included a comparison chart that 1000 -AF electrolytic capacitor between the ground and positive showed characteristics of around thirty models. Last month we voltage input at the clock board. began covering individual makes in alphabetical order. This It seems a shame that Jeffdoesn't alert the builder _J the month we conclude the listing and this series of articles. many options available on this popular clock IC. With the addi- tion of just one SPST or pushbutton switch from pin 32 to the Jeff positive voltage, and using the fast and slow set pushbutton On the plus side, this is a very simple clock circuit with a switches provided, you could display and zero seconds. stop well -made, attractive fully assembled walnut wood -look case. counting for precise time -setting, or reset the entire clock to The heavy red plastic faceplate and Masonite back panel make 12:00:00 AM for use as a 24 -hour elapsed timer! (Real time a sturdy enclosure, and would be a particularly good -looking would be deleted.) This IC also contains alarm anti nooze addition to a recreational vehicle with a wooden interior. The functions, as well as a 59- minute countdown timer ("s.eep ") finished clock is much smaller than the case, so a different with the addition of some other switches. enclosure could be used if overall size is important. Perhaps by the time you read this article some of these "min- The circuitry is as basic as you can get, with no frills. The uses" will be corrected. The kit has the basic ingredient; for a National MM5316 (or equivalent Fairchild 3817, which has "gourmet" van or motorhome clock, at a "diet special" price! brighter digits) is a clock IC with direct drive, so no resistors or Jeff, 3015 Eaton Rd., Cleveland, OH 44122. transistor drivers are used to operate the FND503 digits. Also, since there is no multiplexing, RFI is at a minimum. The IC, however, runs very hot. In the unit I built, a 33 -ohm half-watt National resistor was used in the 12 -volt input line to keep the MM5316 This completely assembled and calibrated 12 VDC Aatomo- from overheating with the display on. tive /Instrument Clock Module is available from Digi -Key (Box Fast and slow setting switches are included in the kit, as well 677, Thief River Falls, MN 56701) with three pust button as all the MM5369 crystal oscillator parts. The digits are inge- switches for $24.95, while Radio Shack sells the same module, niously arranged so that the four decimal points are used as a without switches and for the same price, as their No. 27-1003. colon between the hours and minutes digits, and as AM and PM Several other distributors offer this module without switches for indicators. the same or higher prices. On the minus side, are the altogether too brief instructions Two of the switches set the hours and minutes independently

(one sheet on one side). Adequate for a builder experienced in at a 1 -Hz rate. Setting minutes zeros the seconds, altlongh the

digital clocks, they would be pretty hopeless for a beginner. seconds cannot be displayed. The colon blinks on for 1 second

Although the assembly is not difficult, it requires a lot of and off for 1 second. Accuracy is provided by an or -board patience. The two PC boards are designed so that 30 jumpers 2.097152 -MHz crystal timebase, adjusted to the profer fre- are required between them (although they are straight across), quency by National. The third switch turns on the fluorescent and the display board requires seven jumpers -all of which display when the ignition is off. Provision is made for vtiriable make an otherwise simple assembly a tedious job. dimming of the display by wiring to the parking light an= dash - Also, there is absolutely no voltage transient or reversal lamp control of your vehicle. However, Fig. 3 shows a simple protection, which could be provided by some diodes, capacitors way, (not shown in the module data sheet) to wire a SPST and resistors. If you have a problem with false readings in your "bright- dim "' switch without tampering with the vehicle light- 45

www.americanradiohistory.com ing circuits. has no jumpers, and greatly reduces the possibility of oversol-

This module can be packaged in a 3 X 2 X 1 -inch plastic box dering under the digits (with hidden bridges) and the difficul- (with the terminals sticking out the side), making it one of the ties of unsoldering that existed with the previous two -sided PC smallest complete clocks reviewed in this article, and -since it display board. Circuitry changes include the addition of a 250- requires only the addition of switches -the simplest kit. The µF filter capacitor at the reset pin of the IC and increasing the bright blue -green display shows clearly through blue, green or power -supply filter to 1000 #F to provide better transient yellow faceplates, but loses brightness behind a red lens. protection. If you'd like to mount this in a circular dashboard clock A high -quality mica -dielectric trimmer with zero tempera- space, Enclosure Engineering, 3491 Butcher Drive, Santa ture coefficient is used for trimming the crystal frequency. A

HOURS SET diode has been added and the AC power circuit revised to blank

WIRE COLORS the display when the AC power is interrupted and the backup ON XANTECH CLOCK battery is installed; this way the clock will keep running for days TOP during power interruptions without losing time. With the orig- FRONT WHITE a VIEW GNO6 GROUND inal circuit, when battery was used with AC operation, the DIM MA1003 N/C 5 GREEN BRIGHT display didn't blank with loss of AC power, and the battery PARK LIGHTS 4 RED would last only a few hours. BATTERY 3 *12V DASH LAMPS 2 Optoelectronics has gone all out to make this kit complete BLACK IGNITION 1 ACCESSORY and easy to build, with very good instructions, a detailed sche- matic and high -quality components and PC boards. Even the

DISPLAY ON packaging of the kit parts is outstanding. The parts are logically MINUTES SET grouped and sealed in separate compartments of two long 5- inch -wide polyethylene strips. You snip open each FIG. 3- NATIONAL MA1003 CLOCK display and time -setting switches. compartment with scissors as you need the clearly visible parts. That sure Clara, CA 95951 will make you a bronze- colored plexiglas disc, beats little paper bags and envelopes! cut to your required diameter and drilled to mount the model The model 7005 was not yet available when this was written MA -1003, for about $3. Write Robert C. Arp for details. in May, 1977, but advance information provided at that time National Semiconductor Corp., 2900 Semiconductor Dr., San- indicates this is a very versatile unit, based on the popular CT- ta Clara, CA 95951. 7001 clock IC. It is the only design reviewed that has both a calendar and an elapsed -time function that retains real time. Nexus The model AC -1 AC power pack is available from Optoelec- This is a small but easy -to- assemble six -digit car clock with tronics for operating any of their clocks from the 117-VAC wall very bright red digits. The case is vacuum -formed into a tapered plug. It sells for $2.95, and can be used with any of the other shape that roughly follows the shape of the PC boards, an clocks in this report that have a 12 -VAC input. Optoelectronics, attractive compact design. A ball- socket pedestal mount is Inc., Box 219, Hollywood, FL 33022. with included the case to allow swiveling if desired. Ouest Time is set by pushing a common straight pin through a fast - This clock, designed by C. a or slow -set pinhole in the bottom of the case! The display and Robert Arp, features National Semiconductor preassembled and tested MA I012A clock boards connect together directly, and no switch wiring is four -digit 12 -hour required, making this one of the simpler kits to assemble. Two 60 -Hz digital electronic clock module, complete with ' /,- inch -high readouts. An MM5639 crystal timebase is on a Zener diodes, a blocking diode, an inductor and two capacitors are included to provide excellent reverse and transient voltage separate PC board. Two IC voltage regulators (12 volts for the protection. clock circuits, 6 volts for the display), two diodes and three capacitors are wired a a Although the instructions don't point this out, you can choose to terminal strip; photocell and three resistors are mounted on the module. Only a few wires are either a 12- or a 24 -hour format. As built, a 12 -hour format is necessary to interwire, making this a simple kit. The switches displayed. For a 24 -hour display, cut the printed circuit path are miniature test -point jacks, mounted on the the from pin 10 of the MM53I4 to ground, and let pin 10 float. Be front of optional case, sure to use shielded wire in connecting this clock to your vehicle standard gray which has plenty of room for the parts. Even three heat sinks are furnished with the basic kit, an electrical system (some shielded wire is provided in the kit) or outstanding buy for $15.95. the RFI will be noticeable. Nexus Trading Co., Box 3357, San Leandro, CA 94578. The alarm option consists of a speaker, transistor, resistors and switches that attach to the module for a 24 -hour repeatable Optoelectronics alarm with snooze. The automatic dimming circuit, included in the basic kit, has a broad range and is effective in providing The model 2001 is included in this report because several thousands were sold before the new model 2001R replaced it at the same price with a number of improvements. For example, model 2001R has a RESET switch and uses special tested M M5314's that reset after about 5 seconds to 0 00 00 in the 12 - hour mode and 00 00 00 in the 24 -hour mode. This allows it to be used as a 12- or 24 -hour elapsed timer that counts by the second without retaining real time. In addition to the RESET switch, a HOLD -COUNT and DISPLAY- ENABLE switch are in- cluded. The HOLD switch lets you set the clock to the second; in the elapsed -time mode you can stop and restart without going back to zero. The DISPLAY -ENABLE switch lets you operate the display with the ignition off. In AC operation, this same switch blanks the display to save power! The thicker .062 -inch fiber glass PC boards are plated for INSIDE SABTRONICS SI -204 CLOCK (top). easy soldering and are well made, with very cleanly drilled holes and sharp, clear white silk- screened parts layouts on royal blue S.D. SALES JUMBO CLOCK alarm boards. A separate small PC board is placed parallel to the option (top right). cabinet -front time -setting access holes to make it easier to set the hours and minutes. The display PC board is single- sided, SABTRONICS SI -204 PARTS.

www.americanradiohistory.com good display contrast. S.D. Sales By the time you read this, Quest says that they will be using a Using a Mostek 50252 clock IC and a Bowmar '/_ -im.h -high PC board for the miscellaneous parts instead of a terminal strip. four -digit readout display, this design offers various; options. Also, a pushbutton switch will be added to display seconds, hold Unfortunately, the instructions are somewhat confusin3, some count, or reset the module to 12 AM for use as a 24 -hour information is omitted, and the physical arrangement of the stopclock-all at no increase in price! Quest Electronics, Box parts makes it a difficult to assemble and package. You ¡.et a lot 4430, Santa Clara, CA 95054. of parts for the low price, and an alarm option is onl: $1.50 more. Fortunately, the Optoelectronics Cabinet II me- tioned Ramsey earlier is an almost custom -made enclosure for this relatively The model DC -7 is totally different in appearance and large clock. construction from the other mobile clocks. John Ramsey had a The display requires 40 straight- through short -wir.: jumpers special die made for extruding these modern aluminum cases, to mate it to the display board, and 17 more wires, r ly iength, and uses them for several of his clock designs. Also unusual is are needed to join the display board to various scattered onnec- the fact that the buyer can choose five anodized colors at no tion points on the clock PC board. Therefore, you can remote extra charge. A red Polaroid faceplate is also included. Three the display if you prefer. The clock board is large enoetg not to single -sided PC boards are used in a compact assembly that be crowded, but it contains 17 resistors, 14 transistor:. seven slides into the end of the case. The three time -setting push- diodes, two large electrolytic capacitors, one trimmer. :a,acitor, button switches mount in predrilled holes in the rear of the case a 3.58 -MHz crystal, a small capacitor, the clock IC and three at the other end, and matching colored tapered aluminum more IC's used for the crystal oscillator and who knmrs what endcaps finish off the "space -age" look. The instructions arc else, since they're not shown on the schematic. It's not exactly a well written and illustrated, making the clock easy to assemble. simple clock! The easy -to- follow schematic includes a well -written explana- Once built, it operates nicely and even has automatic tion of multiplexing, which should help considerably in trouble- dimming. shooting. If you like wiring, lots of parts, versatility and custom -pack- aging, this might be your favorite clock; if you like simplicity +12V 0 CdS PHOTOCELL DISPLAY and small size, you'll hate it! S.D. Sales Co., Box 28810, Dallas, GROUND RETURN TX 75228. NPN o Tonitron 27011 Tonitron is the only source found in this survey for units that combine a mobile clock with radio converters. Fos example, model TC -73 ($56.50) has an FM converter in the same cabinet FIG. 4- RAMSEY AUTOMATIC DIMMER for any Fosket -type car clock. as the model TC -76 clock. A horizontally moving LII is used as a dial indicator when tuning FM stations on your A 44 radio The model DC-11D is a standard Fosket car clock with a (at a fixed spot on the AM dial). The model TC -74' (.$51.95) unique dimmer option (see Fig. 4). A CdS photocell varies the CB converter uses a switch to feed CB signals to be tuned in on forward bias applied to the base of a transistor, and that varies the AM radio dial; model TC-75 ($48.95) works the same way the resistance in the display ground return circuit. A 270 -ohm for listening to weather stations on an FM radio. The basic resistor across the transistor provides a conducting path in model TC-76 clock can display seconds, has a bri;tht /dim complete darkness, for minimum display intensity. Component switch and can be used as an elapsed timer without rztaining values for the dimmer have been selected to vary the intensity real time. Tonitron Industries, Box 2251, Elkhart, EN 46514. from full brightness in high ambient lighting to 50 percent brightness in the dark. This results in a relatively constant Xantech contrast (difference between display brightness and surround- A beautiful example of product styling, this unit is t iandard ing light). The clock is readable in bright surroundings, but National model MA1003 clock module in an attra. cive case, doesn't shine like a beacon in the dark -this could be important with three front -mounted minipushbuttons to set hcurs and in nightdriving! minutes and command the display with the ienilion off. The model DM -I Dimmer Adapter Kit is available from Ramsey for $3. Instructions are detailed and well illustrated. Ramsey Electronics, Box 4072, Rochester, NY 14610. Sabtronics Although this is another basic Fosket car clock, a few extras are added even though the selling price is the lowest for a Fosket car clock. A HOLD switch is included, so that this six - digit clock can be set slightly ahead of the real time and stopped until the real time catches up to the clock reading. This may not seem important when you consider that all mobile clocks are inherently inaccurate by as much as several seconds a day but APPLIED MARKETING VC -502 in APPLIED MARKETING LC -101. why display seconds if you can't set them? By the way, any dash -mounting. LCD readout visible im sunlight. MM5314 IC can have this feature, by simply connecting a pushbutton, slide or toggle switch from pin 13 to ground. Xantech is in the premium van, recreational and mariu acces- The other plus is the way the components are packaged in sory business, and this black plastic case with walnut v nyl trim sealed compartments of long plastic strips. You can easily check has a lot of class. The gimbal mounting permits the clock to against the parts list and find what you need when you need it, swivel completely around as well as up and down The four without searching through many little polyethylene bags. leads allow you to wire it to the dashboard dimmer ;witch -or The instructions, which may be much improved by the time you could use Fig. 3 to connect it with a bright /dim switch. you read this, were considered "fair" rather than "good" only The dashboard version is identical except for a ca e designed because of their poor reproduction, not their content. They for that purpose. contain all the necessary detail for anyone but a real beginner to This clock was seen for sale at a large auto supply store and a assemble this clock successfully. Sabtronics International, Box recreational vehicle accessory outlet for $39.95. Xanl.eei Corp., 64683 -R, Dallas, TX 75206. 13038 Saticoy St., North Hollywood, CA 91605. R -E 47

www.americanradiohistory.com 3

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4- ßNQ G gN: 7 w y. G Secret Messages M f t C 9 qaJVWaL3 9-,R t Q l R ke Looking for a new way to use your computer? Try J ®Fp`t deciphering secret messages and breaking codes. bG p° O Its a natural for your computer and plenty of fun. QQXG

FREDERICK W. CHESSON

THE BEALE PAPER NO. I SUPPOSEDLY A collection of jumbled alphabetical often used interchangeably, cipher is gen- describes the exact location of a treasure and geometric figures is shown in Fig. 1. erally considered an overall term for an trove of gold, silver and gems deposited This represents the second in a series of enciphering process. Code more narrowly about 1820 somewhere near Bedford, alleged messages from "Zodiac," the describes a process in which a complete VA. The message is the first part of a slayer of at least 10 persons in the San word, phrase or entire sentence is re- famous cryptographic trio. The second Francisco Bay area, circa 1969. The text placed by a group of letters or numbers. describes the treasure and was solved is reported to contain information con- many years ago using the Declaration of cerning Zodiac's true identity. If deci- Cipher groups Independence as a key. The third paper is phering the cryptogram leads to the kill- There are two major groups of ciphers, said to give the names of the treasure - er's arrest and conviction, a reward of at both with a host of subdivisions. A trans- party members and their next of kin. least satisfaction, if not a monetary pre- position cipher scrambles its original let- Ever since the second paper was deci- sentation, may await the lucky code - ters or words about according to routes or phered, many attempts have been made breaker. geometrical patterns. The word "cipher" to find the key to the first and third can be transposed into "perchi," for messages. Neither the Bible, Shake- Terminology example. speare, the United States Constitution or Code -making and breaking has its own Substitution ciphers are often found in any other federal documents have pro- terminology, as follows: Cryptology their simplest form in many newspaper vided any clues. covers the entire scope of secret commu- cryptogram puzzles. Plaintext letters are In recent years, treasure hunters with nications: Written codes and ciphers, in- replaced by other letters or numbers, metal detectors, "alleged decipher - visible inks, microdots, voice scrambling, according to a general formula and with ments," and some cryptic clairvoyant infrared and ultraviolet signaling and a particular key, which indicates which revelations have roamed the mountain even electronic jamming and count- letter will become what other letter or countryside, much to the annoyance of ermeasures. number. In the simple- substitution ci- local property owners. Cryptography concerns the written pher, the key remains the same for the Meanwhile, back in the computer labs, word, whether transmitted by paper or entire message; the letter E is always endless reams of printouts spew forth and electronically. Enciphering is that pro- replaced by X, A by Q, T by Z, etc. video displays scan flickering alpha - cess by which information is rendered More secure systems use multilettered numerics, as new key -texts and endless unintelligible to the uninitiated. Normal keys, in which E is replaced by J the first variations of old ones are statistically words, or plaintext, are converted into time it is used, then by F, then by W or analyzed for meaningful letter patterns. ciphertext. When ciphertext is prepared even by itself. Generally speaking, the It is, in fact, from the data -processing for transmission or just received, the longer and more random the key, the area of the Beale treasure hunt that the message is called a cryptogram. Deci- safer the message. only so far known monetary reward has phering refers to the reverse process, in A modern practical system is pseudo- materialized. In 1970, Dr. Carl Hammer, which ciphertext is again turned into random key -generator. This system, director of the UNIVAC Division, plaintext for all to read. An unauthorized operating on shift -register principles, Washington, DC, was awarded the $500 attempt to break the cryptogram is vari- produces an apparently random series of first prize for his paper: "Signature Si- ously described as decrypting, cryptana!- bits and zeros, which may be further mulation and Certain Cryptographic ysis or simply old- fashioned code-break- transformed into equally random -ap- Codes," by the Third Annual Simulation ing. pearing key letters or numbers. A 20- Symposium. While the terms code and cipher are stage register could, for example, provide

www.americanradiohistory.com a nonrepetitive stream of over one million TVT modifications "THERE KU CVLTHER E. . Al- bits. The 512- character memory of the orig- though there isn't much firm sta_istical The code -breakers, however, have used inal TV Typewriter is adequate for most information in this brief fragmer t, you computer -assisted cryptanalysis to prove cryptograms. Even 256 characters are can feel reasonably confident in substi- that what is not purely random can be sufficient for the majority of these puz- tutingK= I, U = S, C = A, V = N, fairly quickly broken. Today, the prob- zles, and 128 will work for most of the and L = O, giving "THERE LS AN- lems of secure data transmission between "recreational cryptopuzzles." OTHER ONE." computer centers and terminals are the You need some sort of "store and The trial decipher process can be con- latest chapter in a story as old as compare" circuit. This permits a char- sidered an "examine and replace" logic recorded history itself. acter that will be replaced to be tempo- routine as follows: "Does memos, loca- rarily stored and compared with the oth- tion 1 = A? If yes, replace loci tion 1 Microcomputer -based cryptography er characters in the memory, one step at with B and go to the next location If no, Even the most basic microcomputer, a time. When a match is made, then the go on to the next location. Confine until combined with an ASCII keyboard input character in question is replaced by an- the nth location has been examinec ." The basic flow chart is shown in Fig. 2 The hardware for this TV Typewriter HE R> y - /1 V P>i i® l_ T G e (3 routine consists of a 74174 hexla.ch for storing the character to be replaced, and g r: 0 2 D w y < O K "R -9- an 8160 6 -bit comparator, for determin- ing whether the particular character in G \ CI) -6- u . L the memory being examined is the same as in the hexlatch. The general circuitry Sq ii-Jvai 9 O+ + R Ke is shown in Fig. 3.

L L M - a 1 F P+Po >1/ Operation C L; e To encode a message, first clear the c R/\ F J O-loG F> D( screen, leave a few blanks and v ,rite in the normal alphabet from A to Z. On the f:3 i1 :L Ls D >: G V -4- 1_ 1 © -1- ;) 0 e next line, directly below, type in the written in N + D L L1 cipher alphabet. Having then ,5 G e T 3 Z :[7 Y4 the message and checked it for accuracy, home the cursor and turn off tie WRITE Q < 3JX AO41)K M+ 8+7 R®F ENABLE. The choice of an enciphering a:phabet J u v+ /1 J- + o c1 L! < FB'< - -+ is his corres oondents. up to the user and In hobby -type cryptography, generally U + R / C J r E I Dy 89 8 T M K o no plain letter is represented by itself in íT O the ciphertext. Two typical cipher alpha- cd < "D .J R .T IN M-1- r ß F bets are shown below: N ® F B R A I 4-0 S El+ D(PI Plain: A B C D E F G H J K L N N, etc. 8 O V ® 1- + + Cipher: Q W E R T Y U I O P A S C F, etc. G F N A -1 0 0 0 Plain: ABCDEFGH I JKLN N,etc. Y T I C A B D E F G, etc. ,J Cipher: Z K R P \ G t0 EX l.. E > V U Z Notice the key word, kryptic, in the C - f , (P N¡ O G D second cipher alphabet. Sometimes the 1 D I) 4 a q A plain alphabet is keyed; somet mes both RD T-I- L Oc F J w 8 1 -e- L alphabets are keyed. It is only necessary that letters not be repeated. Some solvers + t/ P O 5 H T1 cl) consider recovering keywords as interest- ing as solving the message itself. 1 r Cl v/ < ! B D Y O B ® -- CD To encipher "A," depress the fi key on the keyboard,while briefly eng4 ing the oz3A 1 K1-+ WRITE key or switch. Now press .he Q, Z, FIG. 1-SECOND ZODIAC MESSAGE of 1969 contains the identity of the killer. or whatever key the cipher eq Bivalent represents, and activate the CLEAR and a video display output, can perform other one by depressing a selected key on switch. This should cause every I. on the many cryptographic functions, including the keyboard. video display to be replaced by ), Z or encoding, decoding and cryptanalysis. For example: Consider "XYZQZ KU equivalent. Similarly, proceed down the

Such things as FORTRAN or BASIC CVLXYZQ LVZ . . ." Noting that Z alphabet to Z (assuming the message has compilers and line printer outputs for occurs rather frequently, you could sub- a Z in its text), noting that e:ae:ih plain hard copy, while useful accessories, are stitute E, the most common letter in the letter is replaced by its cipher equiva- not really necessary for the beginner to English language. First Z is keyed into lent. try cryptography. the temporary memory, then the memory Decoding is similar. For accuracy, As a matter of fact, a slight modifica- is scanned, with the replacement E keyed again just write in the plaintext and tion to the TV Typewriter circuit (see in. Every time a Z is encountered in the cipher alphabets, one above :he: other, Radio -Electronics, September 1973 is- cipher -text, it is replaced by E. This before entering the message. W ien you sue) will permit the device to code and results in the displayed text now ap- have finished replacement, there should decode simple substitution- cipher mes- pearing as: "XYEQE KU CVLXYEQ be two normal alphabets above U e plain -

sages, and to make trial decipherments LVE . . ." The location of the two E's in text message, which will serve as a check for a wide variety of other substitution - the first word suggests "there." Substi- that all the cipher letters ha, ,e been type ciphers. tuting X = T, Y = H, and Q = R yields processed.

www.americanradiohistory.com ENTER AANDB 74174 8160 HEX HEX INITIALIZE LATCH COMPARATOR CONDITIONS DATA INPUT N=1 FOR INPUT BITIO 01 AI B1 .a-0 MEMORY OUTPUT 20 02 )& 2518 INPUTS) A2 B2 ----0 COMPARE: 3 03 A3 B3 DOES MEMORYIN) -f-0 =q 4 04 A4 B4

5 05 A5 05 COMP

6 O6 A6 B6 f-0 nOUTPUT CLR STROBE OUT J L TO RL SUBSTITUTE: V WRITE MEMO RYIN) 1K BUS B TO MEMORY INPUTS --1

ENABLE - O N=Ni1 INCREMENT TO NEXT FIG. 3- EXAMINE AND REPLACE circuit for the TV Typewriter. MEMORY LOCATION FIG. 2 -FLOW CHART for substituting letter B grams) have their own frequency - lind that X, I, V, Z, and O are the high- for letter A in a of N memory letters. count precedence, such as TH, est, then they and the others can be HE, AN, IN, ER, RE, ED, EN, THE, replaced by: AND, ION, ING, ENT, ARE, FOR. Cryptanalysis 6. Letter patterns help: when V -W- X I V Z OT Y AB The following suggestions can help in X-X-V-Y suggests L- I- T- T -L -E, 1 2 3 4 5 6 7 8 9 the solution of simple- substitution cryp- and Q- K- Y -G -Y, the commonly The problem can also be tograms: used T- H- E -R -E. eliminated by having an upper- and lower -case 1. Frequency count: The letter "E" 7. Word patterns are also useful. If char- is the most common in the En- XYZ appears frequently, it may acter set. It also helps to have the original glish language. The other vowels, well be THE, and WM XYZ or JU ciphertext permanently on view. This can except for "U," show a high per- XYZ might turn out to be IS THE, be done by writing in the trial decipher- centage as well. For standard En- or OF THE. ment letters under the cryptogram letters glish, the precedence is: E T A O I When writing in a trial solution, try to as follows: NSHRDLUCPFMWYBGV avoid confusing cipher letters for plain - KQXJZ. text trial letters. If the cryptogram con- XYZQZ KU CVLXYZQ LVZ 2. Single letters are almost always A tains E, T, A, I, etc., replace these at the THERE T HER E or I. start with numerics, like 1, 2, 3, 4, etc. 3. Vowels and consonants tend to With the 63- character set available on The circuitry requires some additional alternate, as E -R -E, D -A -N, etc. the original TV Typewriter and most 4. Certain letters tend to form re- IC's; but in cryptograms of under about versals: ER -RE, ES -SE, ED -DE, similar sets, transpose the cryptogram's 250 letters (and spaces), it eliminates etc. letters into nonalphabetic numeric char- lengthy keyboard rewriting when the 5. Two- and three -letter combina- acters. For example, if you make a cryptanalysis becomes hopelessly gar- tions (called di -grams and tri- frequency count of the cryptogram and bled. R -E

Digital clocks and watches win ited for their innovative design. casts news of interest to the entire spec- places in design show "Billboard styling" is introduced in one trum of CB enthusiasts, from seasoned device, the Billboard electronic digital veterans to laymen. The programs include The second annual Design and Engineer- clock radio. Among other features, the news stories on the latest equipment and ing Exhibition, held in Chicago this sum- clock includes an alarm display that indi- technology, FCC regulation updates, spe- mer, selected among its exhibits two Zenith cates the exact minute to which the alarm is cial events, celebrity interviews, as well as electronic time -display devices, among the set. A power reserve feature keeps the human interest stories. 83 consumer electronics products exhib- clock circuits functioning for up to four hours in the event of an accidental discon- nection from the line or a power failure. CB industry group backs FCC The other device, the Port Royal elec- rulings tronic quartz watch, combines digital and traditional approaches, featuring hands - The EIA's Citizens Radio Section, a for hours minutes and and -dial display and group of CB manufacturers working with an LED digital display for reading out the the Federal Trade Commission on improv- seconds and date. This new model is man- ing CB radio rules, recently endorsed a ufactured by Zenith Time S.A. in Switzer- ruling barring the sale and use of linear land, will be available in the United and amplifiers. These amplifiers, which raise CB States this Fall. station power to more than the 4 watts The Design and Engineering Show is allowable, provide considerable amounts Electronics sponsored by the Consumer of interference to CB's and other electronic Group of the Electronic Industries Associa- equipment. tion (EIA). The CB group has also backed a pro- posed FCC rule change on the type accep- Teamsters sponsor daily CB tance of commercially produced amateur newscast radio equipment. It is recognized that there are two groups of such equipment: one The International Brotherhood of Team- designed for legitimate amateur use, the sters who, more than any other group, has other purporting to be such but actually "BILLBOARD" AM /FM CLOCK RADIO, the Ze- the intended for improper use. Although the nith J465W, presents a design innovation, the been responsible for tremendous "billboard" mounting, in clock radios. Place- growth and popularity of CB radios, are latter equipment is rarely sold to legitimate ment of the display and the large illuminated providing a daily public service newscast to amateurs, the Citizens Group believes that numbers make the clock readable even across participating radio stations. a ruling on type acceptance would be in the a room. The National CB Radio Network broad- public interest. R -E 50

www.americanradiohistory.com AM

STEREO IIIIIIIIIIIIIIIIII] IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII' MIN III 53 60 70 80 100 120 140 161) xiokHz Broadcast Systems For AM Stereo A number of different systems have been conceived in the years since AM stereo was first proposed. The FCC may soon select one as the standard

LEN FELDMAN CONTRIBUTING HI -FI EDITOR

BY THE TIME YOU READ THIS, THE NATION - rules for stereo AM broadcasting. posed phase deviation of one radian. In al AM Stereophonic Radio Committee When this committee began, at least addition, a 5 -Hz subaudible torn: is fre- (an audio industry group formed under five proponents offered stereo AM broad- quency- modulated into the carrier with a the auspices of the Electronic Industries cast techniques for consideration. These deviation of approximately IOCI Az. This Association) will have completed its lab were Leonard Kahn (whose stereo AM tone is for stereo identification I s ru lar to and field tests in Bethesda, MD. These system has been successfully used in the way a I9 -kHz pilot carrier - stereo tests arc the culmination of a long series transmissions from Mexico for many FM lights an indicator on the -_ceiver) of events dating back to the I950's, when years), RCA, Magnavox, Motorola and and is an attractive selling point the Federal Communications Commis- Sansui. In recent months (and in the field A block diagram of the e:lmplete sion was asked to make rules for stereo- tests themselves), the number of systems transmitter system is shown it Fig. I. phonic FM broadcasting. At that time, it has narrowed down to three: Magnavox, The transmitter uses nearly all of an was proposed that rules also be made for Motorola and the Belar Company (whose existing monophonic AM t- emitter stereophonic AM broadcasting as well as system is essentially that proposed origi- with no modification. The chanr el oscil- for the stereophonic broadcasting of the nally by RCA). While the mathematics lator is replaced with a phase- m dulated audio portion of TV. of each of the remaining systems is rather signal generator and signal tor. source. Rule making was initiated only for complex, we will review briefly how each This signal generation methol provides stereo FM broadcasts at that time, and in system works and what changes must be for on- frequency operation, cli -.inating 1961, compatible stereo FM broadcast- made in transmitting and receiving the need for multiplying or mixing ing began. It was felt that there was no equipment in order to handle each of the stages. The station carrier is g: Iterated real need for stereo sound on TV and three remaining systems. on- frequency and modulated u it i a 5 -Hz that, in the case of stereo AM, owners of tone. This signal is then used as a refer- AM broadcast stations were doing quite Magnavox system ence for a wideband phase-locked-loop to well financially, whereas FM station The proposed Magnavox stereo AM generate a true phase -modulated (PM) owners were facing extreme economic broadcasting system is an AM /PM signal on- frequency. The latter >ignal is hardships. To bolster the FM situation, (Phase Modulation) system that places then amplified and modulates by the action was first taken with regard to left -plus -right (L + R) information on a L + R audio signal in the existi:g trans- stereo FM to give those stations a clear phase -modulated channel with a pro- mitter. The processing blocko hown at advantage over their AM competition. RESPONSE & '0 TENNA At present, FM broadcasting is an L R EXISTING DELAY ;BYEM LIMITER MODULATOR extremely healthy industry (some say it COMPENSATION has surpassed the older AM in its eco- nomic success), and it is the AM broad- f EXISTING L R RESPONSE & PHASE-LOCKED- fl casters who have been crying for help! LIMITER .a-. DELAY LOOP RF Apparently, if timetables hold, help is on COMPENSATION MODULATOR TRANSMITTER the way. Before long, the FCC will be examining the massive amount of data STEREO IDENTIFICATION vCn submitted to it by the NAMSRC (Na- TONE

tional AM Stereophonic Radio Commit- FIG. 1 -- TRANSMITTER FOR MAGNAVOX SYSTEM uses a phase locked -loop to prod I., a phase tee) with an eye towards setting up new modulated carrier. The audio signals are limited and compressed after matrixing.

www.americanradiohistory.com the left of Fig. 1 limit and compress (as left and right audio signals using simple component is modulated with L - R to required) the audio signals after matrix - product detectors, one for each channel. provide a suppressed carrier signal in ing. This technique insures that the L + In its simplest form, the Motorola system quadrature with the first. The two signals R loudness for the monophonic program can cause distortion in mono receivers are added and limited to create an output listener will be maintained during recep- when the left and right signals have signal that drives the high -power trans- tion of a stereo broadcast; and that, for significantly differing program content. mitter stages, which are phase -modu- the stereo listener, proper loudness track- This distortion is due to the use of current lated with the same phase information ing will be maintained between the L + rectifiers or envelope detectors in a mon- contained in the composite of the two R and L - R signals. ophonic AM set. modulated signals in quadrature. The receiver configuration shown in The final version of the Motorola pro- The transmitter modulator is supplied Fig. 2 is considered by Magnavox to be posal slightly modified the radiated qua- with L + R to provide a compatible envelope signal for detection by a signal vcO current or envelope detector. Figure 4 is a block diagram of a H TONE STEREO receiver for the Motorola system. The ^tl DET INDICATOR receiver is similar to one used for the ANT ^L reception of two signals in quadrature, LIMITER & PHASE SQUELCH DETECTOR FILTLOWER except that the carrier -level modulator 0 DETECTOR H restores the received signal to its original quadrature carrier form where the left P R STEREO and right signals can be taken directly MONO á L SWITCH from two product detectors. The in -phase i= ^}- L detector can be used for squelch or auxil- iary controls in addition to controlling gain. AM AGC CET Motorola cites several advantages for FIG. 2- RECEIVER FOR MAGNAVOX SYSTEM has single IF. A standard envelope detector recovers their system: the AM channel. The phase -modulated information is recovered by a PLL. 1. A minimum of monophonic cov- erage loss due to sky -wave side - band distortion of low- frequency one of the main advantages of their drature signal. The result is that distor- audio signals. system. It is a single IF system and uses a tion normally appearing in the mono 2. The power spectrum at the trans- standard envelope detector for the AM receiver is transferred to the stereo re- mitter signal closely resembles channel. Since the carrier level is main- ceiver, where it is corrected to restore the monophonic for the most stable tained for all program material, an auto- original quadrature signal. The quadra- compatible performance on mon- matic -gain control system capable of ture signal is then decoded by a pair of ophonic receivers. holding the L + R output nearly con- product multipliers to derive the left and 3. Left and right signals can be stant over a wide range of RF levels can right audio signals directly. directly recovered from the de- modulators without matrixing be achieved. This allows for proper de- Figure 3 is a block diagram of a trans- sum and difference signals. matrixing of the L + R and L R mitter modified to produce a compatible - 4. Compatibility with monophonic signals. The PM information is recovered quadrature signal. The transmitter uses receivers using envelope detec- sampling I by the F signal, limiting it and the carrier -frequency oscillator to supply tion or synchronous detection. detecting it with a phase- locked -loop cir- a signal to the modified exciter. The cuit. exciter splits the carrier into two compo- Belar system The stereo identification tone is regen- nents in quadrature phase. The first com- The Belar system is essentially the one erated by recovering the audio tone that ponent is modulated by L + R, and part originally proposed by RCA. The RCA exists between the main voltage -con- of the oscillator signal bypasses the bal- Corporation is not an active proponent in trolled oscillator and the loop filter and anced modulator to provide a residual the present stereo AM considerations. passing it through a second phase- locked- carrier of the L + R phase. The second This system uses a pre- emphasized loop circuit to drive an indicator. Left - and right -channel information is recov- MODIFIED EXCITER ered a from standard matrix. In addition, BALANCED T an automatic mode switch that chooses MODULATORI between mono and stereo is driven by the presence or absence of the stereo signal. f LIMITER CARRIER CARRIER SUMMING RF FREQ LEVEL POWER NETWORK Motorola system OSC CONTROL AMPL

The Motorola system basically in- +R volves transmitting two signals on one 1L

BALANCED TIME I HIGH LEVEL carrier by separately modulating two car- MODULATOR DELAY MODULATOR riers at the same frequency and arrang- ing in phase L _ then quadrature with re- SUMMING spect to each other. In color TV this NETWORK is method used to transmit two separate SUMMING -R color signals on a single subcarrier. NETWORK The phase of the existing broadcast carrier can be split into two separate L INPUT PROGRAM components, angularly displaced by 90 41. LEVEL LIMITER degrees and each component can be sepa- rately modulated with one of the audio \ R INPUT PROGRAM LEVEL signals. The method provides a relatively LIMITER simple modification of existing transmit- FIG. 3- TRANSMITTER FOR MOTOROLA SYSTEM modula es two carriers in phase quadrature. The ters and stereo receivers that derive the modified exciter splits the carrier into two components in quadrature phase. 52

www.americanradiohistory.com L -R signal to frequency -modulate the tember 1960 issue of The RCA Review. fewer system results to be analyzed carrier. The resulting signal is amplitude - In this modified system, the output of a (there were five proponents of stereo FM, modulated with the monophonic sum sig- balanced discriminator would be inde- all competing for acceptance). Also, nal, L + R. A transmitter block diagram pendent of the AM modulation and equal pressure from the public and 4)+4 sta- for this AM /FM system is shown in Fig. to (L + R), provided the carrier frequen- tions (all very much accustomed tc stereo 5. The FM exciter, carrying the L - R cy is at the discriminator null. However, records, tapes and FM broadcast.) may modulation, replaces the ordinary fixed - this system is highly subject to AM -to- cause the FCC to move more rapidly this frequency crystal exciter that would be FM crosstalk if the receiver is detuned time. In any event, when and if a system used in ordinary monophonic AM trans- and therefore requires some form of AFC is approved, you can be sure that manu- mission. circuitry to insure perfect tuning. facturers will scurry to be out there with Figure 6 shows a receiver that would suitable stereo AM tuners and receivers be suitable for use with this AM /FM When will stereo AM begin? as quickly as possible. system. The output of the common IF No one can predict when or even if the One final word regarding sterco AM amplifier is fed to circuits that provide FCC will decide upon one of the systems is, perhaps, in order. As most readers are amplitude- insensitive FM detection. A described here. If past history is any indi- aware, AM as broadcast and received in form of dynamic limiter (preceding the cation, in the case of stereo FM, the field this country can hardly be consicered a discriminator) is shown. Because the tests were completed in early 1960 and a "high- fidelity" broadcast mediun. Not diodes are self- biasing, the output is pro- final report was submitted to the FCC that it could never be! There are many portional to the mean level of the IF shortly thereafter. The report and order AM stations in this country tho.t take signal and no tracking circuitry is approving the currently used stereo FM pride in broadcasting audio signals hav- required. system were issued by the FCC in April, ing a frequency response right out to A variation of this system, known as an 1961. By the summer of that year, the 15,000 Hz, just like FM. However, most AM /FM /AM system, in which the FM first stations began transmitting stereo- AM receivers and tuners are unable to modulating signal is modified to (L - phonically. reproduce much above 4 or 5 kHz, and R)/(1 + L + R), was also investigated There are some indications that the many AM broadcast stations us= stan- by RCA. A definitive paper on this mod- FCC may move more rapidly in the case dard telephone lines to pipe their signals ified system was published in the Sep- of stereo AM. For one thing, there are from studios to transmitters, and these lines have about the same high -frequency BALANCED R OUTPUT limitations. MODULATOR response GATE So, unless you own one of the few wideband AM receivers, and unless sta- RF TUNER CARRIER BALANCEO L OUTPUT tions start using high -fidelity lines when --e---- LEVEL MODULATOR IF AMPL MODULATOR GATE stereo AM is finally approved. }ou will 1 not hear Hi -Fi over AM just because you .7 can receive separate left and rieht chan- IN -PHASE PHASE nels. The musical instrument and vocal DETECTOR sounds may move to their proper stage locations -and that will certainly lend

QUADRATURE LOOP some excitement to AM reception but -e. VCO PHASE -e. LOW-PASS those instrumerts and DETECTOR FILTER the fidelity of I accus- J voices will still be as low as you ant tomed to hearing over AM. R -E PHASE LOCKED -LOOP CIRCUIT FIG. 4- RECEIVER FOR MOTOROLA SYSTEM. Phase -locked -loop and balanced modulators recover the R and L signals. MONO AUDIO Infrared sensing device forecasts clear air turbulence

LIMITING L Clear air turbulence (CAT) is an annoy- AMPLIFIER O TRANSMITTER DIODE ing, and potentially dangerous, aice effect

L R T of modern air travel. To help cut c own on MATRIX -B serious injury and aircraft damage :hat can L R POWER result from insufficient warning of CAT SUPPLY CRYSTAL occurrence, scientists at the U.S. Depart- EXCITER ment of Commerce National OceEnic and LIMITING FM Atmospheric Administration lab and at AMPLIFIER EXCITER NASA have devised an infrared sensing FIG. 5- TRANSMITTER FOR BELAR SYSTEM. The carrier is frequency modula ed by the difference instrument. signal and amplitude modulated by the sum signal. The device is a simple water -vapor radio- meter system that can detect CA "- from 4 OUTPUT to 10 minutes in advance and at a distance AM DETECTOR MATRIX of up to 160 kilometers. Installed in the fl right wheel well of the aircraft, the radio- OUTPUT meter is angled upward at a fixed elevation RF & IF . DISCRIMINATOR STAGES of 2.5° to 15.0 °. The detector and optical system in the device pick up water -vapor emissions in the field of view and also from DOUBLE-DIODE background emissions, which thus help DYNAMIC LIMITER generate the signal. flights with a prototype I( Fifty -one test 1 showed that the device is accura e about 80% of the time. This high per:eltage of T T timely warnings certainly warrant making this device available as part of :ho regular aircraft FIG. 6- RECEIVER FOR BELAR SYSTEM uses a dynamic limiter circuit to provide AM- insensitive FM subsonic (and perhaps supersonic) detection. on -board instrumentation. R -E 53

www.americanradiohistory.com Radio -Electronics

e ,; Tests GTE Sylvania e CIRCLE 83 ON FREE INFORMATION CARD Model 2600 Stereo Receiver

LEN FELDMAN CONTRIBUTING HI -FI EDITOR TABLE I RADIO -ELECTRONICS PRODUCT TEST REPORT Manufacturer: GTE Sylvania Model: GTE SYLVANIA'S MODEL 2600 STEREO RECEIVER GTE -2600 is an elegantly designed high -power unit that FM PERFORMANCE MEASUREMENTS offers new features not commonly found in SENSITIVITY, NOISE AND R -E R -E most medium -priced integrated receivers. FREEDOM FROM INTERFERENCE Measurement Evaluation I shows the Figure front panel of the IHF sensitivity, mono: (EV) (dBf) 1.7(9.8) Excellent receiver. The power switch, phone jacks and a Sensitivity, stereo (pV) (dBf) 4.0(17.2) Excellent mono microphone input jack are placed at the 50 -dB quieting signal, mono (pV) (dBf) 2.4(12.8) Excellent lower left of the light- colored flat panel. The 50 -dB quieting signal, stereo (AV) (dBf) 33(35.6) Very good microphone jack feeds signals to both stereo Maximum S/N ratio, mono (dB) 72 Very good Maximum S/N ratio, channels and can be used for instrument stereo (dB) 66 Good Capture ratio (dB) 1.5 pickups as well as conventional microphones. Good AM suppression (dB) 47 Fair Toggle switches select A or B speaker sys- Image rejection (dB) 55 Fair tems. Rotary knobs control BASS, MIDRANGE IF rejection (dB) 66 Fair and TREBLE tone, as well as BALANCE and Spurious rejection (dB) 87 Good master VOLUME settings. Two rows of push- Alternate channel selectivity (dB) 68 Good buttons (six buttons per row) take care of all FIDELITY AND DISTORTION MEASUREMENTS other control I and selection functions: PHONO Frequency response, 50 Hz to 15 kHz (± dB) -2.0 Fair PHONO 2 or (pressing both these controls Harmonic distortion, 1 kHz, mono ( %) 0.15 Excellent actuates the microphone input circuit, which Harmonic distortion, 1 kHz, stereo ( %) 0.27 Good cannot be mixed with other program sources); Harmonic distortion, 100 Hz, mono ( %) 0.20 Good Harmonic ( AUX, AM, FM, FM MUTE; TAPE I and TAPE 2 distortion, 100 Hz, stereo %) 0.30 Good Harmonic ( monitoring; low- and high -cut FILTER; MONO/ distortion, 6 kHz, mono %) 0.12 Very good Harmonic distortion, 6 kHz, stereo ( %) STEREO and LOUDNESS. 0.40 Very good Distortion at 50 -dB quieting, mono ( %) 0.7 Good In the upper portion of the panel, a large Distortion at 50 -dB quieting, stereo ( %) 0.4 Very good cutout area contains a linear FM dial scale, an STEREO PERFORMANCE MEASUREMENTS AM frequency scale and a linearly calibrated Stereo threshold (µV) (dBf) logging scale. 4.0(17.2) Excellent Separation, 1 kHz (dB) 46 Excellent Also included are a flywheel- coupled tuning Separation, 100 Hz (dB) 48 Excellent knob, signal strength and center -of- channel Separation, 10 kHz (dB) 25 Good tuning meters, a stereo indicator LED and two MISCELLANEOUS MEASUREMENTS more LED indicators that indicate the ampli- Muting threshold (µV) (dBf) 3.0(14.7) Excellent fier- output clipping level for each stereo chan- Dial calibration accuracy (± kHz at MHz) -500 at 88 Poor nel separately. The smooth- acting dial pointer OVERALL FM PERFORMANCE RATING is illuminated when power is applied to the Very good receiver. The built -in AM ferrite -bar antenna, sup- MANUFACTURER'S PUBLISHED SPECIFICATIONS plied separately, must be plugged in by a TUNER SECTION: connector and installed in its mounting brack- IHF Sensitivity: 1.8 pV (10.3 dBf). 50 -dB Quieting: mono, 3.0 pV (14.8 dBf). Signal -to- et on the rear panel when the receiver is Noise Ratio: mono, 70 dB. Capture Ratio: 1.5 dB. Image Rejection: 55 dB. IF Rejec- unpacked. (This unusual arrangement is prob- tion: 65 dB. Selectivity: 67 dB. AM Suppression: 45 dB. Spurious Rejection: 80 dB. ably intended to prevent the ferrite stick from THD: mono, 0.3% at 1 kHz; stereo, 0.3% at 1 kHz. FM Muting Threshold: 2.7 pV (13.0 breaking during shipment and unpacking.) dBf). Below the AM bar antenna are external AM AM TUNER SECTION: terminals, 75 -ohm or 300 -ohm FM antennas, Sensitivity: 200 pV -per- meter. Image Rejection: 63 dB. two sets of phono inputs, an input impedance Selectivity: 35 dB. switch connected with the phono -I inputs and AMPLIFIER SECTION: a chassis ground terminal. Auxiliary and two Power Output: 80- watts -per -channel, 8 -ohm loads, 20 Hz to 20 kHz; 100- watts -per- sets of tape inputs and outputs come next, channel, 4 -ohm loads. Rated THD: 0.1% at 8 ohms; 0.15% at 4 ohms. Damping Factor: followed by jumper -connected preamplifier - 35. IM Distortion: 0.1% at 8 ohms; 0.15% at 4 ohms. Frequency Response: phono, out /main amplifier -in jacks and three sets of RIAA ±0.8 dB; high level, 20 Hz to 20 kHz, ± 1.0 dB. Input Sensitivities: phono, 2.5 speaker -connection spring- loaded terminals. mV; high level, 250 mV; mike, 5 mV. Phono Overload: 80 mV. Signal -to -Noise Ratio: Why are there three sets of terminals, when phono, 80 -dB referenced to 10 mV; high -level inputs: 86 dB; mike, 65 -dB referenced to the front panel provides choices for only two 10 -mV input. Bass & Treble Control Action: ± 11.0 dB at 100 Hz and 10 kHz; mid- pairs of speakers? Simply because Sylvania range, ±6.0 dB at 1 kHz. Filter Action: -3 dB at 90 Hz and 7 kHz (12 dB per octave). has provided a passive matrix system that GENERAL SPECIFICATIONS: allows recovery of out -of -phase ambience data Dimensions: 18'/< W X 61/2 H X 15'/2- inches D. Suggested Retail Price: $599.95. from stereo records, which is then reproduced

www.americanradiohistory.com via speakers mounted behind the listener. This manufacturer's published performance claims. kind of "poor man's quadriphonic" listening The few specifications included in the bro- experience, which is similar to the Dynaco chure and owner's manual (incomplete in system in the early days of four -channel sound terms of compliance with the new IHF /IEEE experimentation, requires only two additional tuner measurement standards) were generally speakers but no additional electronic compo- met or exceeded. However, such secondary nents. A slide switch on the rear panel turns on specifications as image rejection and AM sup- those so- called "rear" speakers if they are pression were somewhat disappointing in a connected to the "PQ -4" terminals. The rear receiver of this price category. panel also has a pair of unswitched conve- Stereo separation was more than adequate nience AC receptacles and one switched AC across the entire audio frequency range, as can receptacle. be seen in Fig. 2. Muting and stereo threshold were properly set in view of the tuner quieting Tuner section and distortion characteristics. Dial calibration A summary of our FM tuner measurements was poor, however, with maximum error oc- will be found in Table I for comparison with curring at the low end (88 MHz). Amplifier section Table II clearly shows that the aur5c section TABLE II is of a higher quality than the tuna- section. RADIO -ELECTRONICS PRODUCT TEST REPORT Power output exceeded published chi -is even at the audio frequency extremes. Cui phono Manufacturer: GTE Sylvania Model GTE -2600 hum and noise measurements are r:fo renced AMPLIFIER PERFORMANCE MEASUREMENTS to the rated input sensitivity of 2.5 m V. so that they would translate to some 12-s: B higher R -E R -E to the manufacturer's 10- POWER OUTPUT CAPABILITY Measurement Evaluation numbers if referred mV input. RMS power /channel, 8 -ohms, 1 kHz (watts) 98 Excellent RMS power /channel, 8 -ohms, 20 Hz (watts) 90 Excellent RMS power /channel, 8 -ohms, 20 kHz (watts) 90 Excellent RMS power /channel, 4 -ohms, 1 kHz (watts) 135 Excellent RMS power /channel, 4 -ohms, 20 Hz (watts) 119 Excellent RMS power /channel, 4 -ohms, 20 kHz (watts) 120 Excellent Frequency limits for rated output (Hz -kHz) 10 to 25 Excellent DISTORTION MEASUREMENTS Harmonic distortion at rated output, 1 kHz ( %) 0.014 Excellent Intermodulation distortion, rated output ( %) 0.037 Very good Harmonic distortion at 1 -watt output, 1 kHz ( %) 0.02 Very good Intermodulation distortion at 1 -watt output ( %) 0.014 Excellent DAMPING FACTOR, AT 8 OHMS 35 Very good PHONO PREAMPLIFIER MEASUREMENTS Frequency response (RIAA r dB) 1.0 Good Maximum input before overload (mV) 90 Good to fair Hum /noise referred to full output (dB) (at rated input sensitivity) 70/71 Excellent HIGH LEVEL INPUT MEASUREMENTS Frequency response (Hz -kHz, ± dB) 10-35, 1.0 Excellent Hum /noise referred to full output (dB) 90 Excellent Residual hum /noise (min. volume) (dB) 90 Good TONAL COMPENSATION MEASUREMENTS Action of bass and treble controls See Fig. 3 Excellent Action of secondary tone controls See Fig. 3 Excellent Action of low- frequency filter(s) See Fig. 4 Good Action of high- frequency filter(s) See Fig. 4 Good COMPONENT MATCHING MEASUREMENTS Input sensitivity, phono 1 /phono 2 (mV) 2.5/2.5 Input sensitivity, auxiliary input(s) (mV) 250 Input sensitivity, tape input(s) (mV) 250 Output level, tape output(s) (mV) 250 Output level, headphone jack(s) (V or mW) 100 mW The BASS, MIDRANGE and TREBLE 'one con- Excellent Ease of servicing trol range is shown in Fig. 3, whi e low- and OVERALL AMPLIFIER PERFORMANCE RATING Excellent high -cut filter response is shown Fig. 4. Phono overload measured 90 mV. compared TABLE Ill with the 80 mV claimed; this input capability OVERALL PRODUCT ANALYSIS should pose no problems except ,x, th the very Retail Price $599.95 highest output phono cartridges t. at trace Price Category Medium -high heavily modulated record grooves. We gener- Price /Performance Ratio Very good ally feel that a 100 -mV phono input overload Styling and Appearance Excellent Sound Quality Very good capability is all that is necessarj Lnder the Mechanical Performance Very good average record -playing conditions t to model 2600 comes close to meeting that hi t figure. Comments: After a period during which Sylvania withdrew from the hi -fi component market, they have returned with the model GTE -2600. On the whole, the amplifier section rates Summary slightly higher than the tuner section, which, although certainly adequate in this price Our overall product analysis, roae_her with category, is hampered by somewhat deficient AM suppession and image rejection. In some listening situations this could pose interference problems, although we did not our comments and reactions to tie listening experience any in our tests. The amplifier section, however, is well designed and quality of the model 2600, will he 'ound in delivers a clean, open and tight sound with a minimum of coloration. There is no tape - Table III. This well- designed recei .e is simple to -tape dubbing via front -panel switching, but two tape- monitor circuits and two to operate, includes many of h: desired phono -input circuits offset this deficiency to some degree. Tone control, including the control features, and, if somewhat deficient in midrange addition, is very good. Reproduction via the phono inputs is excellent. tuner performance, compensates I'm- those de- As in GTE's earlier receivers, construction is primarily on one major circuit board, ficiencies with its conservatively designed with parts well identified and easily accessible for servicing. preamplifier and amplifier section-. R -E

www.americanradiohistory.com Onkyo TX -8500 ,

AM /FM Receiver CIRCLE 84 ON FREE INFORMATION CARD

LEN FELDMAN CONTRIBUTING HI -FI EDITOR TABLE I RADIO -ELECTRONICS PRODUCT TEST REPORT WHEN WE FIRST LOOKED AT THE ONKYO MODEL TX-8500 receiver (see Fig. 1), its long, low Manufacturer: Onkyo Model: TX -8500 profile did not indicate that it was the heavy- FM PERFORMANCE MEASUREMENTS weight (over 65 lbs. shipping weight) that it turned out to be. This ruggedly constructed SENSITIVITY, NOISE AND R -E R -E FREEDOM FROM unit is at the top of Onkyo's integrated INTERFERENCE Measurement Evaluation IHF sensitivity, mono: (AV) (dBf) receiver line, and if you believe that "one 1.7 (9.8) Excellent Sensitivity, stereo (MV) (dBf) 3.9 (17.0) Very good receiver is pretty much like another," you may 50-dB quieting signal, mono (MV) (dBf) 3.0 (14.7) Very good be surprised at some of its innovations. 50-dB quieting signal, stereo (AV) (dBf) 55.0 (40.0) Fair The long dial area, covered by a clear plastic Maximum S/N ratio, mono (dB) 74.0 Very good plate, contains signal -strength and center -tune Maximum S/N ratio, stereo (dB) 65.0 Good meters at the left in addition to the linearly Capture ratio (dB) 1.5 Good calibrated FM and conventional AM dial AM suppression (dB) 50 Good scales. FM calibration points appear at every Image rejection (dB) 85 Very good IF rejection (dB) 100+ Excellent 100 kHz, and a well -illuminated dial pointer is Spurious rejection (dB) 95 Excellent controlled by the tuning knob to the right. Alternate channel selectivity (dB) 70 Very good Indicator lights above the dial scales show the program source, and two additional lighted FIDELITY AND DISTORTION MEASUREMENTS Frequency response, 50 Hz to 15 kHz ( ± dB) words, LOCKED and TUNED, operate in Con- 0.35 Very good Harmbnic distortion, 1 kHz, mono ( %) 0.13 Excellent junction with Onkyo's unique Quartz -Lock Harmonic distortion, 1 kHz, stereo ( %) 0.25 Good tuning system. Harmonic distortion, 100 Hz, mono ( %) 0.17 Very good All other operating controls are neatly Harmonic distortion, 100 Hz, stereo ( %) 0.37 Very good arranged in a single row across the lower Harmonic distortion, 6 kHz, mono ( %) 0.13 Excellent section of the panel. A rectangular power on/ Harmonic distortion, 6 kHz, stereo ( %) 0.60 Good off pushbutton at the lower left is located adja- Distortion at 50 -dB quieting, mono ( %) 0.42 Good cent to the usual headphone jack. Following Distortion at 50 -dB quieting, stereo ( %) 0.40 Good these are the speaker selection switch, BASS, STEREO PERFORMANCE MEASUREMENTS MID -range and TREBLE tone controls, each Stereo threshold (NV) (dBf) 3.9 (17.0) Very good

1 equipped with I I click -stop positions. A chan- Separation, kHz (dB) 46 Excellent nel BALANCE control is also located in this Separation, 100 Hz (dB) 43 Excellent Separation, 10 kHz (dB) area. 30 Very good Five round pushbuttons near the panel cen- MISCELLANEOUS MEASUREMENTS ter handle low- and high -cut filters, audio Muting threshold (AV) (dBf) 4.5 (18.3) Very good Dial calibration accuracy ( ±kHz at MHz) Fair muting ( -20 dB), stereo /mono selection and -300 loudness control. A rotary volume control with OVERALL FM PERFORMANCE RATING Very good 41 detent stops comes next, followed by five more pushbuttons for FM muting defeat (and defeat of the auto-lock feature), a Dolby FM MANUFACTURER'S PUBLISHED SPECIFICATIONS: (which adapter switch breaks the circuit for FM TUNER SECTION: insertion of an accessory Dolby adapter and Usable Sensitivity: (mono), 1.7 sV (9.8 dBf); stereo, 4.0 µV (17.2 dBf). 50 -dB Quieting also changes the FM de- emphasis to the Sensitivity: mono, 3.0 µV (14.7 dBf); stereo, 35 sV (36 dBf). Capture Ratio: 1.5 dB. required 25 µs), and three tape- monitor Image Rejection: 83 dB. IF Rejection: 100 dB. Spurious Rejection: 95 dB. S/N Ratio: switches. A program selector switch completes mono, 70 dB; stereo, 65 dB. Selectivity: 70 dB. AM Suppression: 50 dB. THD: mono, the front -panel layout. 0.15% at 1 kHz; stereo, 0.3% at 1 kHz. Frequency Response: 30 Hz to 15 kHz, t 1.5 There are 45 well- marked connectors on the dB. Stereo Separation: 40 dB at 1 kHz; 32 dB from 70 to 10,000 Hz. Muting Level: 4.0 rear -panel of the model TX -8500. As many as AV (17.2 dBf). Stereo Threshold: 4.0 µV (17.2 dBf). Subcarrier Suppression: 60 dB. three pairs of loudspeakers can be connected to the spring- loaded type terminals. One AM TUNER SECTION: switched and two unswitched AC outlets and a Image Rejection: 55 dB. IF Rejection: 55 dB. S/N Ratio: 45 dB. Harmonic Distortion: line fuseholder are mounted near the speaker 0.8 %. terminals. At the upper left, near the pivotable AMPLIFIER SECTION: AM ferrite -bar antenna, terminals handle Power Output: 110 watts -per -channel into 8 ohms (150 watts into 4 ohms), 20 Hz to 20 connection of an external AM antenna, and kHz. Rated THD: 0.1 %. Rated IM: 0.1 %. Damping Factor: 50 into 8 ohms at 1 kHz. 75 -ohm or 300 -ohm external FM antenna Frequency Response: high level, 15 Hz to 30 kHz, ± 1.0 dB; phono, RIAA, ±0.2 dB. U_ connections. Input and output jacks for a tape Input Sensitivity: phono, 2.5 mV; high level, 150 mV. Phono Overload: 250 mV. Tone Z deck (including twin sets of phono inputs) are Control Range: bass, ± 10 dB at 100 Hz; mid -range, ±5 dB at 1.2 kHz; treble, ± 10 dB ¢ located along the lower section of the rear at 10 kHz. S/N Ratio: phono, 75 dB, IHF "A "; high level at 90 dB, IHF "A." High- and panel, as are preamplifier- output main ampli- Ú Low -Filter Cut -Off Frequencies: 100 Hz at 6 kHz (12 dB per octave). L fier -input jacks that are interconnected by

I-1;1 wire jumpers. An FM detector output jack is GENERAL SPECIFICATIONS: O located near a three -position switch that deter- Suggested Retail Price: $699.95. Dimensions: 227/8 W X 6% H X 1715/,6 inches D. o mines the sensitivity of the automatic tune - Weight: 55 lbs. cc lock feature. 56

www.americanradiohistory.com Even with the wood cabinet removed, it is see itse i since TABLE II still difficult to inside the unit the entire tuner section is well sl.ielded. RADIO -ELECTRONICS PRODUCT TEST REPORT Alignment points are accessible through la- tuner shield. A perforated Manufacturer: Onkyo Model: TX -8500 beled holes in this black metal protective cover also ob-ct -es the AMPLIFIER PERFORMANCE MEASUREMENTS amplifier and power supply sections. For a R -E R -E better view, this black metal cover 'tas re- POWER OUTPUT CAPABILITY Measurement Evaluation moved to reveal the two completel;: s-parate RMS power/channel, 8 -ohms, 1 kHz (watts) 125 Excellent power supplies and transformers used in this RMS power /channel, 8 -ohms, 20 Hz (watts) 118 Excellent receiver (see Fig. 2). RMS power /channel, 8 -ohms, 20 kHz (watts) 120 Excellent RMS power /channel, 4 -ohms, 1 kHz (watts) 173 Very good RMS power /channel, 4 -ohms, 20 Hz (watts) 160 Excellent RMS power /channel, 4 -ohms, 20 kHz (watts) 158 Excellent Frequency limits for rated output (Hz -kHz) 10 -30 Excellent DISTORTION MEASUREMENTS Harmonic distortion at rated output, 1 kHz (%) 0.01 Excellent Intermodulation distortion, rated output ( %) 0.015 Excellent

Harmonic distortion at 1 -watt output, 1 kHz ( %) 0.026 Very good Intermodulation distortion at 1 -watt output ( %) 0.0055 Excellent DAMPING FACTOR, AT 8 OHMS 50 Very good PHONO PREAMPLIFIER MEASUREMENTS Frequency response (RIAA ± dB) 0.1 Superb Maximum input before overload (mV) 250 Excellent Hum /noise referred to full output (dB) (at rated input sensitivity) 72 (IHF "A ") Very good

HIGH -LEVEL INPUT MEASUREMENTS Recent studies made by Onkyo ant several dB) 7 -39, 1.0 Excellent Frequency response (Hz -kHz, ± other manufacturers show that using indepen- Hum /noise referred to full output (dB) 92 (IHF "A ") Excellent dent power supplies for each of the two stereo Residual hum /noise (minimum volume) (dB) 99 (IHF "A ") Excellent amplifier channels insures against the distor- TONAL COMPENSATION MEASUREMENTS tion caused by signals from one channel cross- controls Very good Action of bass and treble ing over into the other channel via the imped- Action of secondary tone controls Excellent a common power supply. 'Twn power Action of low- frequency filter(s) Excellent ance of to the v eight of Action of high- frequency filter(s) Excellent transformers (besides adding this unit) also insure that full rated Dower is MEASUREMENTS COMPONENT MATCHING available from each channel regardless of Input sensitivity, phono 1 /phono 2 (mV) 2.5/2.5 drawn from the companion i:ht.nnel. Input sensitivity, auxiliary input(s) (mV) 150 power Input sensitivity, tape input(s) (mV) 150 Output level, tape output(s) (mV) 150 Tuning Output level, headphone jack(s) (V or mW) 117 mW The unique Onkyo tuning system uses a quartz -crystal oscillator to generate an ex- EVALUATION OF CONTROLS, CONSTRUCTION AND DESIGN tremely stable frequency. This frequency is Adequacy of program source and monitor switching Excellent then used as the reference for the Utroxl stages Adequacy of input facilities Excellent of the FM circuitry. Even the mos minute Arrangement of controls (panel layout) Very good deviations from optimum tuning are detected Action of controls and switches Excellent and automatically corrected. In ac ual use, Excellent Design and construction when the tuning knob is touched, the tuning - Ease of servicing Very good correction feature is defeated. As r.oc t as you OVERALL AMPLIFIER PERFORMANCE RATING Excellent approach a signal and come close e-ough to proper tuning, the word LOCKED appears on the front panel. The center- of- channe meter is TABLE III then used to tune closer to precise tuning but, even if the optimum tuning Dint is not OVERALL PRODUCT ANALYSIS achieved, releasing the tuning knob activates Retail Price $699.95 the quartz tuning feature and you :a- observe Price Category High that tuning -meter pointer pop righ into its Price /Performance Ratio Very good center point on the scale. Styling and Appearance Excellent As we discovered in later measurenents, the Excellent Sound Quality meter not only indicates proper tun ig (with Mechanical Performance Excellent the word TUNED shown above the dial scale), Comments: When we first saw the term "Quartz- Locked tuning," as it applies to the FM circuitry in but the tuner is, in fact, tuned to its s')solutely the Onkyo receiver, we presumed that this was just another form of AFC circuit. It is far lowest distortion point. In no insttnx during more than that. In fact, it is the closest thing to frequency synthesis that we have seen our THD measurements was it possible to use of varactor diodes (normally found in true frequency - but, by not requiring the manually tune to a lower distortion point (by synthesis tuners), Onkyo gives us nearly perfect tuning accuracy that is not dependent defeating the lock -tune feature) :ht -t by let- upon user judgment or meter interpretations, and the circuit performance obtainable this feature operate! with traditional, multigang capacitor tuning. ting tuner and Although the FM distortion levels have been bettered by competing products in this Aside from this, the rest of tlti:_ price category, the fact that these low distortion levels will always be realized by the amplifier design is fairly conventiona and well user (whereas slight mistuning of other receivers that boast lower THD readings can executed, with the familiar differential input result in much higher distortion) should not be overlooked. Still, if one were to rate the stage and direct -coupled output circuitry used tuner and amplifier sections of this powerful receiver, the amplifier would come out for the power amplifier section. No :. thematic ahead. Its ample power reserve (both with 8 -ohm and 4 -ohm loads) is evident when was supplied with our test sample, se it is diffi- listening to the signals it delivers through even the lowest- efficiency loudspeakers cult to comment on specific circuits. available in our laboratory. Sound is extremely clean, particularly during transient -laden musical passages and FM measurements extreme bass power. Any receiver that boasts in excess of 100 watts -per -channel into 8 -ohm loads and carries a suggested retail price of under $700 is worth serious Table I summarizes the most imps rtant FM consideration. measurements made on the mode! TX -8500. continued or, page 76

www.americanradiohistory.com CONSTRUCTION TECHNIQUE IC :iricklayìng For Miniature Projects

Here's a method of stacking IC's that enables you to build IC- oriented projects into the smallest space possible

WALTER T. CARDWELL, JR.

THE PAST IO YEARS HAVE SEEN A TREMEN- the device. Except for a few linear IC's, only seconds to harden, the IC block can dous growth in both the number and almost every IC made can be obtained in be used immediately. (Note the caution complexity of large -scale integrated cir- a dual in -line package; thus, this tech- on the label about gluing your fingers cuits. Yet, along with the increased com- nique can be used almost everywhere. together because it takes about 30 min- plexity of IC's and thus the necessity for First, cut the leads of the DIP's flush utes of soaking the fingers in nail polish fewer circuits, the reduction in size of with the bottom of the package, as shown remover or acetone to unglue them! Keep

most electronic instruments has not used in Fig. I -a. (Take care not to strain the a bottle handy. A special solvent called the full potential inherent in LSI circuit- leads at the case.) The IC's can be Cyano-solv, manufactured by GC Elec- ry. It is now technically feasible for an IC stacked one on top of the other to any tronics, also softens the glue.) manufacturer to construct almost any height and glued together using a cyano- Once the ends of the block are stacked test instrument -a VOM, signal genera- acrylate-type glue. Since the glue takes vertically, they can be filed smooth, using tor, frequency meter, etc. -into a pen - sized device either by using LSI techniques alone or by a combination of nnnnnnn methods. The obstacle facing such de- a vices is economic and not technical. In the future, we shall be able to carry a complete test bench clipped to a shirt nnn nnnnnnn nn pocket. However, there will always be Fl ri devices that do not justify designing a nnnnnnn nn special IC. This article presents a con- nnn nnnnnnn nn struction method that can be used to make the smallest possible device using nnnn nnnnnnn commercially available IC's. b When IC's were first designed, the standard approach was to transfer dis- r-i rn r-i r1 r7 r7 r--1 1-1 r7 r7 crete circuits into integrated form. Now, IC's are designed to take advantage of the special features of IC technology. U u U U U U u U U U U U U ZJ LJ U LJ U LJ U Nevertheless, once the IC's are out of the r r--1 n r-i n n 1-1 1-7 r-1 r7 ETU-1 r-t n I--I rl r 1 r-I package, the same PC board techniques are used to mount them that were com- mon in the age of vacuum tubes, resulting U LJ U U U U Lu LI U u u u U L U U U U U U in large bulky instruments that in many I--1 r7 r-1 r7 r, r--t rI r-1 r-i r-1 r7 r1 r-t r-i respects look like, and must be used as, museum pieces of the forties and fifties. L] U LJ U U U L U U U U U U -U 0 0 0 U U U Construction techniques c The bricklaying construction tech- FIG. 1 -HOW IC'S ARE STACKED. Drawing a represents a 14 -pin DIP with leads cut flush with case. nique presented in this article uses the IC Diagram b shows how IC's can be stacked in tiers and end -to -end while drawing cis a top view of packages as the supporting structure of IC's stacked vertically, horizontally and laterally.

www.americanradiohistory.com a regular metal file. Two blocks can then Once it is located, remove the wires. If ceramic DIP's except that the cf.scs can't be joined end to end (Fig. I -b) to make a the IC is on the outside of the block, be filed and you may have to add plastic flat sheet of bonded IC's. The IC leads remove it simply by brushing the solvent shims to fill the gaps. Discrete compo- prevent stacking side -by -side but this can along the joint. It generally takes about nents can be glued around the edge of the be overcome by gluing spacers at the ends 30 minutes for the joint to soften enough IC block. Four or five small TO -92 cases of the sheets and then gluing the sheets so that a knife blade can be inserted into can be placed together in a slot ihat an together, as shown in Fig. l -c. The com- the joint to pry the IC apart. If the IC is IC would normally use. These cases are pleted IC block is as strong as the plastic on the inside of the block, you can use not as tall as the DIP's and a shish may case material, and unless you use very several alternatives. If there is enough be needed. thin plastic material, the block is fairly space, just glue a new IC somewhere else One -quarter -watt resistors are added solid. It is impossible to break the IC's and leave the defective one where it is. to the bottom of the IC block. These apart with your bare hands. The IC's However, usually this will not be possible resistors are almost as long as the width will, however, crack if dropped. and the IC must be removed. of the DIP's. Cut the resistor lead; close A second solution is to drill out the old to the body and solder the wire -wrap wire How to wire IC. Use a drill that is smaller than the to the leads. Capacitors must be located To wire the circuits, you have to go height of the case to remove as much of wherever they will fit. (See I ig. 4.) back to the Stone Age and use point -to- the defective IC as possible. Solvent may Neither resistors nor capacitors should be point wiring. This may make the tech- then be applied to remove any remaining used as structural support. The resistor nique unattractive to those in the indus- loose chips. Slip the new IC into place. A bond is to the paint on the resister body, try, although automated point -to -point final alternative is to remove the blocks and the resistor will come off if ar y great wiring is making a comeback. However, of IC's until the defective IC is on the force is applied. Capacitors are usually the experimenter and hobbyist will find it outside of a block; then follow the first not flat, so the surface area of the bond is is much easier and takes less time than to method described above. Sometimes you quite small. if the device is real y to odd- lay out and etch a PC board. can separate two IC's by using a pair of ball type, you can make a specia plastic Use the lead pads on the side of the IC diagonal cutters between them after the support structure for it. package as bonding pads, and make the joint has soaked for about IO minutes. Combining 14- and 16 -lead packages connections with AWG No. 30 solid This method should only be used when may leave gaps at the ends o°' <_ block. wire -wrap wire. Remove '/K -inch of insu- both IC's are inexpensive units since it is When two blocks are joined end to end, a lation and solder the wire to the pads. always possible to damage them both. hole in the IC sheet may result. These The meter shown in Fig. 2 may look like The last problem is that of IC- gener- holes can be used to pass leads fl om one ated heat. For CMOS units at low speeds side to the other and, since the e:td bond there is no problem, but because higher - of even one IC is usually ve y strong, power devices have a large direct contact several holes can be left in the sheet. area, the heat that is generated conducts The cyanoacrylate glues bond almost to adjacent IC's. Place heat -sensitive cir- instantly, and once the IC's are j Dined, it cuits away from high -power devices. In is impossible to align them Froperly. some cases, glue a strip of aluminum or Either line up the IC's first and apply a copper between the IC's to remove the drop of glue at the joint (be careful of generated heat, as shown in Fig. 3. In your fingers), or construct a simple align-

FIG. 2- INSIDE VIEW of a probe -type digital l uf r t e or i0ififlif iftifiiflif frequency meter. Compact construction is due to the "bricklaying" technique. r a "rats nest," but it is actually very easy COPPER OR ALUNII UfII and convenient to work on since there is no bulky chassis to move around. A pair AIR OR FLUID FLOK of sharp -pointed tweezers and a small soldering iron are the only special tools required. FIG. 3 -HEAT SINKS atop and /or on the IC's can be metal slabs, strips or rectangular t.it1 ig. There are several areas that can cause problems. One is the damage that might fact, this method may be better than PC be caused to the IC by clipping the leads board methods, since each IC can be so close to the case and soldering the connected to a heat sink. wires with no heat sink. I thought CMOS This construction method is so conve- units would be especially susceptible to nient that in most cases it is not necessary damage. However, I have wired four to breadboard circuits anymore. You can different instruments and rewired several build and test a small subsection before sections of each instrument without dam- gluing it into the device. Wiring changes aging any IC, including CMOS types. can easily be made at this point, and it is You should, however, take great care not too difficult to remove IC's. All leads when soldering the wires to prevent the are easy to locate and identify, especially FIG. 4- RESISTORS, CAPACITORS Ind other a is, IC from being damaged by excessive if you use standard alignment; that if components are glued wherever there is room. heat. all IC's face the same direction. It is a good idea to keep a location guide handy ment jig, as shown in Fig. 5. fte guides Troubleshooting the IC's since IC type numbers are always hidden may be coated with candle war: to pre- Repair can be a problem. Actually from view. vent the IC's from sticking to them. these circuits are easier than most to troubleshoot since all the signal points Other types of components Case materials are on the side of the IC. Locate the In addition to plastic DIP's, other com- Anyone who has built an electronic faulty IC before trying to remove it. ponents can also be used. You can use device from scratch has faced the prob-

www.americanradiohistory.com general, most metal- and wood -working n n n n n tools can be used. Once the edges are cut, file them flat and at right angles to make an almost invisible seam. The paper masking the material should be left on as long as possible. LJ u LJ LJ LJ u u Acrylic plastics can be cut to any desired shape, and the gloss can then be restored. File the surface, if it is flat, and then wet -sand it with 240 -grit, 400 -grit and finally 600 -grit wet -or -dry sandpap- er. Buff the surface, using a cloth buffing wheel charged with jewelers' rouge. Fig- ure 7 shows a transparent plastic probe tip made this way. Of all the special tools available, none are more useful than a bench with a wheel FIG. 5-A JIG IS USED to hold the IC's in perfect alignment so they can be glued. It is constructed grinder cloth buffing from thin metal strips. and a hard -backed (not rubber) sanding disk.

case made from ' /m-in. black acrylic plas- An alternative to an acrylic plastic tic. The readouts are covered by trans- such as Plexiglas is ABS plastic. This

parent amber plastic. A I 2-pin socket is material is much softer and easier to glued at each end of the IC block to form work with, but it does not have the deep the meter case foundation. If no sockets gloss of Plexiglas. Most hobby stores are needed, substitute a '/a -inch or a '/4- carry it under the name of Plastruct. inch piece of plastic. The sides, top and ABS plastic can be used to make shims bottom of the case can then be made and support pieces inside the device from '/16 -inch plastic, which is very easy where looks are not important. It is also to work with. If you use cyanoacrylate available in much thinner sheets than FIG. 6 -THE COMPLETE FREQUENCY METER. glue, the joints can be opened with a Plexiglas. Its case is just a little longer than a ball -point pen and about three times greater in cross - razor blade. Do not use a solvent on the While the construction technique de- section. joint as it will dissolve the plastic. Do not scribed here was used to make a probe, it use the normal Plexiglas cement because can also be applied to almost any project. lem of what kind of a case to use. The it melts the two surfaces so that the two The method is easy, takes little time, can good old standby, the Minibox, leaves a pieces are fused together. This type of be changed easily and results in the smal- great deal to be desired so far as appear- joint cannot be opened very easily. lest possible device. You can now build ance is concerned. You can use the There are a few tricks that are helpful that beautiful stereo amplifier or pream- construction technique described in this when using acrylic plastics. Thin pieces plifier you have been discouraged from article to solve the problem of a suitable can be scratched and broken like glass. building because of all the mechanical enclosure. Any wood saw will cut thick pieces, but work involved. since the bricklaying tech- Figure 6 shows a frequency meter in a the saw should have fairly fine teeth. In nique eliminates much of that work. R -E

New RCA color TV chassis uses less 1972 color sets. ular 8080 and 8085 microprocessors. power Four years ago, the company took a The second session, called "Digital Elec- RCA recently announced that it has been series of steps to reduce the energy - tronics for Automation Workshop," will converting all its color TV receivers to new consuming capacities of their products by take place December 6 -7, and will concern low -level energy consumption models that introducing a line of solid -state receivers. small -scale and medium -scale TTL IC's. it predicts will save the consumer approxi- They then switched their entire black -and- Many lab hours with breadboarding sta- mately 20 a day. The sets will operate at white line to solid -state operation, elimi- tions and in -depth lectures are planned. about half the power requirements of the nating all power- drawing tubes. From this, Both the three -day and the two -day sem- it was a natural progression to the intro- inars will be under the direction of Dr. Peter duction of their new "XtendedLife" color Rony, Dr. Paul Field and David Larsen. For TV chassis. more information on these programs, write This chassis has four integrated circuits Dr. Norris Bell, Continuing Education Cen- and uses about as much energy as a 100 - ter, Virginia Polytechnic Institute and State watt light bulb, compared with the average University, Blacksburg, VA 24061, or call solid -state color set that uses 145 watts. It (703) 951 -6328. is estimated that, with its projected cost of 26 per day, the "XtendedLife" would set CB license applications up 10% in the consumer back only about $7.70 a 1977 year, a sharp contrast to the $28.88 of The Federal Trade Commission reports older tube -type models. Since the average receiving 3,254,825 applications for CB American family spends 6.3 hours a day licenses during the first six months of this watching its favorite entertainment, both year, a 10% increase in sales over the same energy and cost savings appreciable. period of time in 1976. Since 1958 more than 11 million CB licenses have been Two -part seminar program on issued, over half of which were granted microcomputers during the last year and a half. The Virginia Polytechnic Institute and John Sodolski, president of EIA (Elec- State University at Blacksburg, VA, will tronic Industries Association), states: "It's hold a two -part seminar program in De- obvious that personal two -way communi- The first session, entitled "Micro - cation is fast becoming an integral part of RCA's "XTENDEDLIFE" CHASSIS uses only 89 cember. mobile America." His projection for 1980: watts to power the 19 -inch models. This com- computing Interfacing Workshop," held pares with the average solid -state color TV set December 8 -10, will offer participants a more than 50 million CB's and more than that uses 145 watts. hands -on opportunity to work with the pop- 20 million base stations will be sold. R -E 60

www.americanradiohistory.com What's New In IC's

A GREAT MANY SEMICONDUCTORS WERE The circuit can be used with 40- The circuit is TTL- compatibl . using introduced last summer. Here are de- channel U.S. -manufactured transceivers Schottky -clamped PNP transistors 2t the tails on three that you may find useful. or with German transceivers. The device input and output pins. has search, scan and increment up -and- The 59 X 91 -mil chip comes in a 16- Fairchild IC's down modes. The search mode seeks out pin package. In quantities of IOTA, the A system consisting of 12 of the new either busy or vacant channels. The scan NE564 costs $4.25 per unit. Further Fairchild F4727 seven -stage counters mode stops at each busy channel for information is available from S guetics, generates all the notes of the chromatic three seconds before continuing. 811 East Arques Ave., Sunnyvth! CA music scale over eight octaves. The IC's Information is available from the Exe- 94086. produce each of the seven natural and tron Division, Fairchild Camera and In- five flat and sharp notes for the primary strument Corp., 3105 Alfred St., Santa Voltage regulator scale and for the seven higher octaves, Clara, CA 95050. The TL7805AC voltage regulator which makes the system adaptable to from Texas Instruments is a 5 -roL, l' /_- many electronic musical instruments. In- 50 -MHz phase -locked loop amp three -terminal positive voltag° unit. terface and crosstalk problems are con- Signetics has introduced the NE564 It is protected against overload by cur- sidered minimal. monolithic phase- locked loop for use in rent- limiting and thermal shutdov-i cir- The plastic - packaged part rated for high -speed modems, FSK (Frequency - cuitry. the commercial temperature range has a Shift Keying) receivers and transmitters, The cumulative accuracy anc regula- high -quantity (1,000) price of $1.17. For frequency multipliers and signal genera- tion errors are guaranteed to bee than more information, write the Linear Divi- tors. 3% over full operating condition;. sion, Fairchild Camera and Instrument The NE564 demodulates FM and FSK Mounted in a three -terminal TO -220 Corp., 464 Ellis St., Mountain View, CA signals without additional external cir- plastic power package, the TL70'.AC is 94042. cuitry. Key features are reduced carrier priced at $1.31 each unit in qua it ties of The FCB8010 IC is a Citizens band feedthrough, low noise and single 5 -volt 100. For further details, conta :t Texas radio controller that performs channel supply operation. The typical frequency Instruments, Inc., Inquiry AisJeering selection, automatic scanning and seven - drift is 400 ppm -per- degree C, and the Service, Box 5012, M/S 308 Attn: segment display- driver functions. signal -to -noise ratio is 40 dB. TL7805AC), Dallas, TX 75222 R -E TIME KEEPING EXCELLENCE FROM DIGITAL CONCEP

TIME TUBES ADD A NEW DIMENSION TO TIME ITSELF SYSTEM 5000 THE FULL FEATU CLOCK KIT A bright 0.5 Fluorescent display provides easy to read numbers that Have it your way with S .stem brighten and dim automatically according to the light. The acrylic tube 5000. After the circuit nas been with or hardwood ends gives these clocks a unique look of simple acrylic assembled, add the appropriate elegance. AM /PM & Power Failure Indicators. Alarm Models have easy to jumpers and switches to create a set set indicator. 3.5" X 3.5" X 5.75. beep alarm, snooze, and alarm truely individualized time dece. There are enough features to satisfy the most discrimi rating Complete Kits enthusiasts. Build an Alannt': ock/ C K-2001 Solid Clear Time Tube Ishownl $39.95 Calendar, full feature De ,l. :om- CK-2002 Clear Tube with Walnut Ends $34.95 puter Room, Radio Static r ock, CK-2010 Solid Smoke Time Tube $42.95 or any combination to your CK-2012 Smoke Tube with Walnut Ends $36.95 tastes. FEATURES All models available with alarm features. Add $5.00 and specify "Alarm Version" and model number when ordering. Time of day and duplicate time register, two 2 our alarms, four year calendar, one hour down counte- anal 10- minute snooze and ID turner; Direct -Drive 0.5" fiuc._res- ent panel with automatic brightness, PM and power fail- TIME CUBES LEND AN ELEGANT EFFECT TO ANY HOME OR OFFICE ure indication; Forward or reverse time setting. f -volt battery backup, seconds display on demand. Many rr rep The combines simplicity of design with the ultimate in technology. 2020 Cube System 5000 includes all components, two test .w :hes It features bright fluorescent digits in a contemporary smoke and chrome 0.5" and complete instructions. 1.5" H. X 4" W. X 4" I). enclosure. Includes AM/PM, Power Failure Indication, Easy set controls. Model 2120 is same as above with pleasant beep alarm, photo electronic Case not included. $:4.95 dimming system and alarm set indicator. It also features a 9- minute snooze SYSTEM 5000 OPTIONS which is activated by simply tipping the cube. Alarm on /off switch and relax ar in- "Tilt- Snooze" make wake up time easy to set. 4.5" X 4.5" X 4.7" High. Add RELAY OPTION -$4.00 Includes 700 watt d to your collection with on -time designs from Digital Concepts. terface to control appliances, steroes, etc. s SWITCH OPTION -$3.75 Includes 4 SPST push autrons, 2 DPDT push buttons. and 2 SPST slide switcd es. Pro- Complete Kits grams all major features. CK-2020 Smoke Time Cube $34.95 QUARTZ TIME BASE -$6.95 Generates precise 6: Hz. CK-2120 Smoke Time Cube with Alarm $39.95 output with exceptional stability and accuracy. It rect interface to system 5000 and most other clocks. Iodides all components and instructions.

CASE OPTION 1 -$5.95 Includes simulated walnut Send your check or money order today for rast delivery. Add 5% to total order to cover shipping and cabinet, blue face plate, rear panel, and all mot.rting insurance. Outside Continental U.S., add 10 %. N.J. residents must also add 5% sales tax. Call 12011. hardware. Ideal for many projects. 8.3" X 5" X 3 8" 845 -7102 to charge your order to BankAmericard or Mastercharge. CASE OPTION 11- $11.00 Deluxe hand finish//d, solid 3/8" walnut cabinet, complete with blue or 9r-ter face All clock kits are 100 -120 VAC, 50/60 Hz. plate and rear panel. 5.75" X 5.75" X 3.0 ". All models can be built for 12 or 24 -hour format. We pay and insurance within the Continental U.S. on orders over $100.00. shipping digifral concepfr , 247 ROUTE 46 SADDLE BROOK, N.J.07662 1201) 845 -7101

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Matched transistor pairs. Are they really necessary? that way; the bias was set up for a germanium transistor in the lower half, JACK DARR, SERVICE EDITOR and so naturally a silicon was not prop- erly biased (not "matched! "). A READER ASKED ME IN A RECENT LET- The curve tracer is useful to check if The same basic circuit is used in many ter "Do you really need matched pairs of transistors match. Most of the curve solid -state TV sets, mostly in the vertical transistors in audio amplifiers, etc. ?" tracers provide dual sockets or connec- and audio output stages. These circuits The answer is "Yes." It is essential to tors; so that an instant "A -B" compari- work the same way as the audio circuits, have matched pairs in the common OTL son can be made by slipping a switch. although they have more feedback loops (Output TransformerLess) circuit, using Complementary- symmetry pairs can also for linearity correction, etc. The same a pair of transistors in Class B or Class be checked, but you have to switch from kind of problems will be found. AB, with the load taken off at the PNP to NPN at the same time. Crossover distortion causes compres- midpoint. Since each transistor amplifies sion or stretch of the scanning lines near only one-half of each cycle of the signal, Circuit problems the screen's center. One transistor scans the two must match or the output will not A direct -coupled driver circuit may the top half of the screen, the other one be symmetrical, thus causing distortion. show mismatch problems after transistor the lower half. Peak clipping appears as The distortion can be spotted on a replacement. Here, the base voltage of compression or foldover at the bottom. scope, using a clean sinewave test signal. the output transistor depends on the These stages can display one annoying If you see that the amplitude is unequal driver's collector current. In a few cases symptom: The top half of the picture wit] between the top and bottom halves of the you may have to change the original be perfectly linear, but the bottom half signal, this indicates unmatched tran- driver transistor as well. If the base will be completely gone. When this hap- sistors. The unmatched transistors might voltage doesn't come out right, try a pens, check the bottom transistor; it may also tend to show some crossover distor- substitute with a slightly different beta. be open or have a bad solder joint on the tion, although I haven't actually seen this This problem will usually show up as emitter or base. A scope will quickly pin happen (yet!). incorrect resting (no- signal) current on this one down. So, these two transistors must be the output stage. If this current is too While we're on the subject of audio matched. You can obtain them from the great, then the full -load current may rise circuitry, a very useful book is the Prac- amplifier manufacturer (which is some- sufficiently to damage the new output tice CET Test Journeyman Audio Op- times difficult) or from RCA, G -E, Syl- transistors. This current should always be tion. It simulates the kind of test you'll vania, Motorola, Mallory, Sprague, Ray- checked when output transistors have take for this qualification. There are 75 theon, 1 -R, etc. They all list matched been replaced, and before the amplifier is questions; the sections and headings are pairs for many different power outputs, tested at full load! Normal resting cur- the same as in the actual CET test. You voltages etc. I have checked most of the rent will run from 15 to 25 mA; a 50- to answer the questions, then check to find replacement types and they match very 60 -mA resting current will cause dam- out if you passed. The answers are in the well on my curve tracer. In fact, picking age. One useful feature of stereo ampli- back of the book. It is available from two identical transistors off the shelf fiers, especially if only one channel Bank Wilson Services, P.O. Box 3321, usually shows a very good match! blows, is that you can check the working Warren OH 44485. The book is similar The Transistor Guides published by channel and get a precise figure for both to the FCC Study Guide for license these companies list many sizes in the resting and load current. exams and can help you find out where matched pairs under a single part num- Bias diodes can also cause oddball you need to do a little studying before ber. They also list matched complemen- symptoms. These diodes, usually in an you take the real test. R -E tary- symmetry pairs. (However, I found output- transistor base circuit, set the bias a few "matched pairs" from a nameless and must be good. I've seen an open bias manufacturer that didn't show up all that diode cause instant failure of a brand new service well on my curve tracer!) transistor. I never really figured it out, but it happened right under my nose, This column is for the service tech- literally. questions nician's problems -TV, radio, audio Always check the service data if it's or industrial electronics. We answer available. I once replaced the output RADIATION all questions submitted by service transistors in a small amplifier where one HORIZONTAL technicians on their letterheads indi- of the bad transistors was a silicon. So, I This Emerson 9300 color TV set has vidually, by mail, and the more inter- put in two silicons. I wound up with a some unusual problems. Its horizontal esting ones will be printed here. horrible distortion! Then I checked the hold isn't at all good, and this even If you're really stuck, write us. drivers, bias, etc., to no avail. Finally, I affects the vertical sync. Also; when it's We'll do our best to help you. Don't was amazed to find in the service data turned on, other sets nearby have sync problems a fuzzy vertical line moving forget to enclose a stamped, self- that the top transistor in the pair was a and addressed envelope. If return postage silicon, but the bottom one was ger- across the screen! I need enlighten - is not included we cannot process manium. Since "the book" tells you that mentl-H.G., St Croix, Virgin Islands. your question. Write: Service Editor. both transistors absolutely must be of the Don't we all? The chances are that this Radio -Electronics, 200 Park Avenue same material, I didn't believe it. There- is some kind of horizontal AFC problem South, New York, NY 10003 fore, I put in a germanium transistor and in the Emerson -bad AFC diodes, loss of fixed it. The circuit was designed to work horizontal sync to AFC circuit, etc. This

www.americanradiohistory.com is making the horizontal circuit unstable. positions; if the high voltage is OK, then In turn, the displacement of the hori- check all DC voltages on the picture zontal gating pulse is upsetting other tube. I had an RCA with exactly the DISCWASHEW circuits in the set. same symptoms. The cause turned out to Also, it is obviously radiating far too be a bad solder joint that killed the presents great a "signal" from the horizontal heater voltage to the two color differ- sweep stages. Suggestion; take the scope ence- amplifier tubes that control the pic- probe and wave it around the back of the ture tube grid voltages. Because these Emerson. Look for a place that shows a tubes have zero plate current, their plate very large stray pickup. Try this on a set voltage and the picture tube grid voltages RECORD working normally and you'll see what rose to the supply value. This made the this pulse should look like. This one will grids far too positive, and the picture probably be very "hashy ". Shields miss- tube drew a very heavy and uncontroll- CARE ing. etc. able beam current. You should also be sure that your picture tube screen volt- COLOR SYNC PROBLEM ages aren't set too high. BASICS The color sync is very poor on this The finest record care syste ri is NEGATIVE PICTURE Magnavox T933. The video isn't too good, Discwasher, and the research of the either. The color and tint controls react This CTC -19 has an odd short -time Discwasher labs shows four vials to the way they ought to. However, the color intermittent. The picture goes negative, dramatically extend the fidelity of your sync has hardly any range at all. The tint and then it looks like AGC overload. It's discs: control will throw the color out of sync at hard to catch because it goes in and out 1. Beware of the heat monster. fak- each end, but hold in the centerl-K.S., quickly. -R. S., Brentwood, NY. ing records from very cord con- Ink, AR. There are a couple of things that could ditions to hot conditions, or ay- If colors are correct and the color be causing your trouble. One is an inter- ing records at temperatires in control reacts normally, that much is mittently open filter capacitor, usually excess of 90° F, accelerates. record OK. So, this sound like a problem in the the one on the + 140 -volt line, which wear and distortion. burst transformer. Check this to see if it creates a weird feedback loop through will show a definite peak when tuned. the IF. A bad ground on the first AGC 2. Beware of a "clean" stylus A Also, check for burst on both of the bypass capacitor could also cause your stylus may look clean, but an be after detector diodes. I have seen the same problem because this capacitor vibrates a glazed with contamination symptom in this chassis when one half of lot when the set is being serviced. Just playing two or three records. This the burst transformer secondary was wiggle it back and forth. glaze holds dust which abrasively open. Another clue to this is unequal DC destroys records. Dismasier's voltages on the AFPC diode outputs. SHRINKING RASTER SC -1 Stylus Cleaner is tie pest These should be the same, but opposite The raster in this Emerson 120771 por- way to keep your clean- but -dirty polarity. table shrinks in about an inch from each stylus really clean. side. The current through the gate turn - 3. Do not replay records I. kly.

IF ALIGNMENT off switch in the horizontal output is high- Playing a record more 1h 3n ance I have an old Hammarlund HQ -120X er than it should be and pulls down the every hour causes chemical and radio that works but doesn't seem to have -25 -volt source. Would appreciate physical stress to the vhyl that the sensitivity it should. The data doesn't help. -L. S., Hicksville, NY. will eventually destroy the alum. fell you much about the alignment pro- 1 ran into this once. It turned problem 4. Clean micro-dust before playing. cedures; it just says to "feed a modulated in -off out to be leakage the gate turn Micro -dust is attracted to records signal into the front end and adjust IF switch. This can be replaced by a big and may not be noticeable. °lay- on circuits for maximum reading output power transistor such as a Delco DS -502 ing a dust -contaminated record meter." I'd like to know if there's a better or a Motorola HEP -740. welds this micro -dust irttc the way-A. F., Little Silver, NJ grooves. The Discwasher brush ODDBALL COLOR PROBLEMS There really isn't a better way. There's with a few drops of D3 fluud s the a very sharply tuned crystal filter in the I've seen several Zenith color TV's finest, most convenient w; ä to IF. To find the exact frequency, feed an show unusual raster problems like those remove this threat to ytiur val- IF signal of around 455 kHz into the described by E. C., Los Angeles, CA, in uable record collection. mixer. Tune the signal generator for a "Old Raster" (Radio -Electronics, Au- For technical information on the com- maximum output meter reading. When gust, 1977). The sets had some or all plete line of Discwasher product, see you find this reading, you are right on the these problems: a narrow range of high - your hi-fi specialist or discrimirating crystal frequency. Leave the signal gen- voltage adjustment; a broad range of record store. erator alone, and adjust the IF trans- high -voltage regulation, as if the high - formers for maximum. A low- frequency voltage regulator was poor; a maximum sweep generator lets you see the actual high voltage of less than 26 kV; and a bandpass and tune for symmetry. raster that pulled in from the sides in the For the RF gain, a feed dial -frequency bottom half of the screen (see Fig. 1). signal into the mixer grid; note the read- In all cases, the cure was to replace the ing. Move the signal generator to the RF voltage- dependent resistor (VDR) in the grid and look for an increase. high -voltage regulator circuit. Be sure to use the exact part given in the parts list; BAD FOCUS, BRIGHT LINES in most cases, this is a Zenith 63 -8161. discwasher i This Zenith 4B25C19 has very bad fo- However, this is not the emergency hold - u. cus. In the service position, I get very down VDR in the grid of the horizontal - 1407 N. Providence Pd. bright and blurry lines, and can't turn output tube. Columbia, Missouri 65 ?01 them downl -D. U., Hooker, OK. Thanks very much to Keith R. Casper, This sounds very familiar. Check the Topock, AZ for the hints. high voltage in both normal and service continued on page 74 CIRCLE 3 ON FREE INFORMATq#I CARD

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Interface analog signals to your microcomputer with the then return to read the MP21 data at Analog Input Microperipheral from Burr -Brown. Plus least 40 As later. Alternatively, the MP21 new HALT pin can be periodically checked UHF power transistors. KARL SAVON, SEMICONDUCTOR EDITOR. for a completed conversion; or, for the greatest efficiency, the interrupt mode A PERSISTENT MICROCOMPUTER PROBLEM For high-speed operation, the internal can be used by connecting the MP21 is in communicating with the outside delay can be decreased by connecting a INT pin to, for example, the IRQ (Inter- world. Many systems have several analog resistor between pin 49 and +5 volts. rupt Request) input of a 6800 micropro- inputs that must be sampled and digi- The least efficient but simplest method cessor. As soon as-the multiplexer sam- tized into binary language, and things get for a host microcomputer to take care of ples one of the inputs, the microprocessor involved. The Burr -Brown MP21 is a the delay between the time of the sample can proceed to some other task without possible answer to this problem. and the time the converted value is ready, checking inputs or keeping track of time is to halt the microprocessor for the 40 -As until the completed conversion interrupts Burr -Brown MP21 conversion time. For more efficient use of the processor. The Analog Input Microperipheral in- microprocessor time, the conversion can Various interconnections among pins terfaces with the 6800, 650X and F -8 be started with an LDA instruction, the 63, 65, 67 and 68 adjust the MP21 to a microprocessors without a PIA (Periph- system allowed to do something else and differential input range of ± 1.25, ± 2.5 eral Interface Adapter) or external logic. ANALOG INPUTS Figure 1 shows the MP21 block dia- gram, which includes a high- speed, 8 -bit, ~ W ..... LY analog -to- digital converter, an instru- C C C C C C S 0.-04Mi,WW,COM mentation amplifier, an input multi- < z z z z z z z z z z z z z z z z plexer, timing circuitry address decoding o msro 0000000000000000m^toozar and control logic. Sixteen analog inputs are grouped into AO O two 8- channel analog multiplexers, Al O 8- CHANNEL 8- CHANNEL LATCH ANALOG ANALOG A2 O which allows the inputs to be arranged MULTIPLEXER MULTIPLEXER 16 A3 O either as individual channels or eight A4 differential inputs. Two Mux Enable in- A5 O-1 A6 O0. 177 41 puts and the SIN /DIF pins are wired to A7 O-4... CONTROL MUR OUT LO A8 MUX OUT HI select one of the two modes. c O-1. LOGIC A9 is with á O- ADDRESS Single -ended operation used A10 0-11. DECODER high -level, low -noise inputs. Differential All O--a. AND Al2 CONTROL operation cancels common -mode noise LOGIC A13 O A14 and is recommended at low levels. A MM 1.0 A15O 2 third mode, termed pseudodifferential, IA IN HI ties pin 79 to an external ground that is 7i40--e. 115 o--a. Á6 GAIN ADJUST common to all analog inputs. This mode 3 Á7 is effective when the remote ground is O- INSTRUMENTATION At ADDRESS 78 o-0. SELECT AMPLIFIER noisy, but there is little interference A9 O-8. BB OFFSET ADJUST between the signal generating device and A10 p--+ All O- the MP21. 68 / o- ~ IA OUT is All Each analog input channel ad- O-i IDELAY] R/W o- 600 dressed as a memory location. Address VMAO-a. AOC IN 1 A 13 in 02 CONVERT lines A4 through are provided, °c 0--e. 6.25K 6.25K 67 w COMMAND addition to uncomplemented address óm ADC IN 2 lines AO through A15, so that hardwired RESET 0 HALT O. CONTROL 630 IN LOGIC JI COMP. selection of memory location bands can INT 0.1 STATUS be made. 4 65 BPO The system's minimum conversion DO 0.4- time is 40 µs -35 As for the multiplexer 01 o.-- 8-BIT c 02 O ANALOG-TO- and 5 As for the A/D converter itself. The D3 Of- TRI -STATE DIGITAL CONVERTER host system must accommodate this de- 04 Of- OUTPUT i D5 Or- lay. D6 0. 07 Or-- A delay circuit in the internal convert - command line gives the multiplexer and 52 49 o instrumentation amplifier 35 is to settle. OUTPUT OE AY SELECT AOJ For gains of over 10, additional delay may be needed and can be had by hook- FIG. 1- ANALOG INPUT MICROPERIPHERAL from Burr -Brown accepts either 16 single -ended or 8 ing a capacitor from pin 49 to +5 volts. differential analog signals and interfaces them to a microcomputer.

www.americanradiohistory.com or ±5 volts or single -ended ranges of resistance to arcing and a low thermal work. The MC10803's can be pa:alleled 0 -2.5 and 0 -5 volts. resistance. with MC 10800 bit -slice devices to do The output of the 8 -bit A/D converter The MJ 10011 costs less than the double -precision arithmetic. feeds a three -state output circuit. The BU208 discrete transistor it is designed The MC 10803 contains six 4 -bit regis- output select control lead lets you choose to replace. Its high gain and built -in ters for generating memory addresses between binary or two's complement out- damper make it even more cost -effective. and sending and receiving data. The put coding. You would choose binary For more information, write Motorola coding for unipolar input ranges, so that Semiconductor Products, Inc., Box all eight bits represent magnitude. The 20912, Phoenix, AZ 85036. two's complement output is the best choice for the bipolar input ranges, where the most significant bit is reserved for the sign and the other seven bits are the magnitude. The instrumentation amplifier gain is factory -set accurately to 2 by laser trim- ming, and can be increased to 250, with THE MC10803 INTERFACE for high -toped pro- an external resistor connected between cessors is in a 48 -pin package. pins 1 and 9: Gain = 2 + 50K /Rex,. At high gains, an offset adjustment can be circuits can be connected in parallel for added by connecting a potentiometer be- multiple I/O ports. The MC10803 is tween pins 78 and 80, and returning the mounted in a 48 -pin Quad- fn -Line potentiometer slider to -15 volts. (QU I L) package and is priced in high The MP21 is packaged in an 80 -pin, quantities at $40. package 1.7 X 2.1 X 0.22 -inch ceramic UHF POWER TRANSISTORS from General RCA's Instruction Manu& for the and has an operating temperature range Semiconductor. All three have a collector volt- RCA COSMAC Microterminal The low- quantity price is age of 12.5 and operate in the 380- to 512 MHz of 0° to 70 °C. CDP18S021, No. MPM-212, tells how to $195 each. A data sheet describing the band. use a pocket -calculator -sized data termi- MP21 is from Burr -Brown Re- available Microprocessor developments nal. The Microterminal interface:, direct- search Corporation, International Air- The Motorola MC10803 Memory In- ly with the CDP18S020 Evaluation Kit port Industrial Park, Box 11400, Tucson, terface Function connects between high- support hardware, and can be resigned AZ 85734. speed processor systems such as the into user -built systems. Transistor news MCI0800 4 -bit slice ALU and memory The manual is available for 1,2 from or peripherals. It contains an ALU that RCA, Solid State Division, Bo c 3200, The BLW79, BLW80 and BLW81 reduces the CPU's peripheral -related Somerville, NJ 08876. R -E from Amperex are UHF power tran- sistors with 10 -, 9- and 7 -dB power gains r and 2 -, 4- and 10 -watt outputs, respec- tively. They are designed for high relia- bility and have gold metallization, gold bond wires and diffused emitter ballast- slovreait-W ing. The transistors are characterized for the 380- to 512 -MHz mobile frequency band at a collector voltage of 12.5. aVot The devices are available in flange or stud packages. Low -quantity prices are A bright way for you to $5.25 for the BLW79, $6.50 for the BLW80 and $7.90 for the BLW81. For save on a four-pack of information, write Amperex Electronic Corporation, Hicksville, NY 11802. Perma Power General Semiconductor Industries has - Brites released an 8 -page application data sheet Color on their XGSR series of high -voltage Save money now on a four-pack of the switching transistors. The data sheet con- popular Perma Power C -511 Color -Brite ...while you warm the heart of someone tains a large number of graphs for prac- special with the beautiful gold -plated 15 tical use in applying the 400 -volt, -amp 15" floating heart necklace. Necklaces like transistor family. this sell in fine stores for $4.95, but its The transistors use the CZR process yours free with your purchase. Designed Ñ` i¡99 and are suggested for converter, inverter by Elsa Pareté, its a gift that's sure to bright- á iff! . ., and Class -C and Class -D amplifier appli- en her day. You'll brighten your day too, as , Fp cations. Write General Semiconductor you save more than $1.00 per Britener, on the Britener you use most often. And your cus- Industries, Inc., 2001 West Tenth Place, omers will give you heartfelt thanks, because Tempe, 85281. AZ Model C -511 Color-Brite immediately restores Motorola's MJ 1001 I is a color televi- sharpness, detail and contrast to faded color pic- sion, horizontal -deflection Darlington ture tubes...defers the need to buy a new picture tube. transistor with a built -in damper diode. The current gain is 40, and the break- Offer valid only while supp I y asts. down voltage is 1400. PERMA POWER Hurry to your distributor Al: ay! The monolithic transistor uses a spe- cial glass passivation and high -voltage Electronics inc. 5615 West Howard Avenue Chicago Illinois 60648 Telephone (312) 647 14 TO -3 package. Its main features are a CIRCLE 73 ON FREE INFORMATION CARD

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SCR, Triac, Diac and Quadrac -What they are and how they triggering device called a diac in place of the neon lamp. A diac is really a double work. Plus some useful hints on using heat sinks when diode, and is sometimes called a "bi- soldering. EARL "DOC" SAVAGE, K4SDS, HOBBY EDITOR lateral trigger." A triac and diac are shown schematically in Fig. 2. They can be placed right in the previous circuit at DO YOU KNOW WHAT THE DIFFERENCES are between an SCR, Diac, Triac and MAIN TERMINAL 2 Quadrac? Actually, they are all related DIAC as we shall see in the circuits that TR1AL follow. GATEo MAIN QUADRAC TERMINAL I First, the SCR is a Silicon Controlled T2006LT Rectifier (sometimes called a thyristor). The "silicon rectifier" part is clear TRIAL: RADIO SNACK RS276 -1001 OR RCA 128008 enough: It allows current to pass through DI AC RAOIO SHACK RS276-1050 OR in only one direction. However, the "con- RCA D3202Ú trolled" part means the rectifying action FIG. 2 FIG. 3 is controlled -it can be turned on and off. which triggers the SCR. Adjustment of points A, B and C in place of the SCR The SCR has an anode and a cathode the 150K potentiometer causes the out- and NE -2. Now the dimmer /controller like other rectifiers, but it also has a third put to vary smoothly. The purpose of the has full range rather than half- range. lead called a trigger or gate. The con- neon lamp is twofold. First, it prevents But the story isn't over yet. Somebody trolling is done by applying a voltage to the SCR from falsely triggering due to else came along and put both diac and the trigger lead, usually via a small neon voltage transients on the AC line from the triac in one case. Yes, you're right! lamp. the motor brushes. Second, it also mini- It's called a Quadrac (and, sometimes, a The circuit shown in Fig. 1 is a light mizes variations in the gate potential "triac with trigger "). (A typical quadrac dimmer or motor speed controller using required to trigger the SCR. for this applicaton is the T2006LT by an SCR and an NE -2 neon lamp. You'll However, remembering that this is a Teccor Electronics, PO Box 669, Euless, notice that one side of the AC line input rectifier, you'll realize that the output is TX 76039.) The quadrac (Fig. 3) can is connected directly to the output socket. not AC but is pulsating DC. One -half of also be placed in the Fig. 1 circuit at (Note, too, the use of a grounded wire -a the input is removed, which is shown points A, B and C. Once again, the result three -wire connection should always be clearly by connecting an incandescent is a full -range dimmer /controller. used on AC lines.) The other side of the bulb to the output. Maximum brilliance SCR's, triacs and quadracs come in a AC goes through the SCR, which is is only about one -half of what it is when variety of flavors. In choosing them, you turned off or on. the bulb is connected directly to the AC should be concerned with two character- The output voltage of this circuit is line. The fact that the output can be istics: peak voltage and power rating. The controlled by varying the firing time of varied only from zero to one -half of the peak -voltage rating is that value which the SCR. If the SCR is triggered at the input is a disadvantage in some dimmer/ must not be exceeded by the applied volt- zero crossing -point of the AC waveform, controllers since you can't get up to full age. Keep in mind that this is peak not then the full output potential of the brilliance or speed. RMS voltage. For example, a device circuit is realized. However, if the SCR is Then, somebody decided to put two rated at 50 peak volts cannot have more triggered after the zero -crossing point, SCR's in one case, pointed them in oppo- than 35.7 RMS volts applied -EPk = say at the peak of the positive half-cycle, site directions and called the new device a 1.4 ERMS. Actually, you should leave a then the SCR will conduct only the rest triac. Thus, when properly triggered, a safety margin and limit the device to of the positive half -cycle. Since, in this triac allows the current to pass in both about 30 volts RMS. A 200 -volt unit is case, the SCR conducts for only part of directions, and the output can be varied, normally used in a dimmer /controller for the AC waveform, the RMS output from 0 to 100 %. the AC line. potential is reduced. A triac can be substituted directly for Power ratings are given in terms of The remainder of the circuit simply the SCR in Fig. 1. However, better maximum load current: 3 amps, 6 amps sets the firing time of the neon lamp, control is maintained by using a special and so on. These devices are rated for a good heat sink, so don't get even near the OUTPUT maximum without a good sink attached. If the load draws less than one -half the 150K rated current, a heat sink could be ANODE omitted, but my advice is to use one. rated in watts must be con- 4"7K Any load TRIGGER verted to amps to determine the suitabil- 0 CATHODE 033 AC. ity of a given device. For this you can NE-2 0 INS use T o X OR G- EC106C P(walü) = I(amps) E(v011a) SCR: RADIO SHACK RS276,-IWbi For example, if you use E = 110 volts, a FIG. 1 6 -amp triac can control up to 660 watts

www.americanradiohistory.com DON'T MISS ANY of incandescent lights; a 75 -watt sol- dering iron would require at least a a /4- Get every single issue of Radio -Electronics amp unit. delivered right to your door, and before it The SCR's, diacs, triacs and quadracs appears on the newsstand. Use this cou- can be used on motors: drills, lathes, pon and subscribe now. saws, fans and mixers; and on lights: reading, photographic, microscope, Mail to: Radio -Electronics Christmas tree, floods and spots; and on SUBSCRIPTION DEPT., P.O. BOX 2520, BOULDER, COLO. 80322 heaters: small hot plates, coffee pots, soldering irons and guns. The list is long, Try AUTOCOMP and you may find just one control isn't name (please print) relief fr enough. quick high fuel cost address Heat sinks So many parts are easily destroyed by AUTOCOMP is a continuously update-_ , -icro- city state zip code heat and must be soldered with heat a t you sinks. Most hobbyists run out of sinks computer which reads TRUE MPG drive. Additional pushbutton control: also check offer preferred because they don't solder each connec- give automatic readouts of Time, [lis ante, 1 Year issues ONLY $8.75 as is made. you make six, eight -12 tion it If and Fuel Consumption. You can mor:ite-your or a dozen connections before picking up 0 2 Years -24 issues SAVE MORE $16.50 engine's performance and your vehicle E effi- to solder them, you'll soon (You save $7.50 over newsstand) the iron ciency. AUTOCOMP will help you s,tv< fuel, exhaust your supply of commercial sinks. improve your driving habits, and p`cvi- a you 3 Years-36 issues GREATER SAVINGS $24.50 However, when this happens remember with valuable time and trip dala istall newsstand prices) (You save $11.50 over you have many items on your workbench AUTOCOMP before your next trip :Inr beat 0 Payment enclosed Bill Me you can use in their place: high fuel costs! make good Check here if this is a new subscription 1. Alligator and similar clips sinks especially if the jaws are flattened; Check here if you are extending or renewing 2. Slide -locking and self-closing tweezers your subscription are natural sinks; 3. Needle -nose and other pliers can be Canada same as U.S.A. Extra Post- used if you put a rubber band around the age: Pan American $1.50 per year, handles so they'll stay closed; all other foreign $2.00 per year. 4. Paper clips and metal hair clips can 40J7 even be used as light heat sinks; 5. Sinks for DIP IC's can be quickly made as shown in Fig. 4. Use sheet

FUEL USED - When the FUEL button PROFESSIONAL is depressed, the display indicates the amount of fuel the vehicle has used since last fill -up, beginning of trip, or DISCOUNTS last reset (up to 1000 gallons). DISTANCE TRAVELED - When the 01ST button is depressed, the display Texas Instruments indicates the distance the vehicle has electronic calculator traveled since the last reset (up to 1000 miles). TI-1750 LCD 519.35 SR -40 . ..523.25 TI-2550 III 23.25 SR-52 II 47.05 INSTANT MILES /GALLON - When the Little Prof 12.55 TI57 NEW 63.00 INST MPG button is depressed. the dis- Dataman NEW 19.95 TI -58 NEW 95.79 gal- Ti-5100 38.75 TI -59 NEW .219.95 play indicates how many miles per TI-5015 NEW 63.00 PC-100A.... 147.00 lon the vehicle is attaining at each Tl -5050M 77.55 MBA. 66.95 moment (up to 200 mpg). 5040P0 95.00 Money Mgr. 16.98 TI-305P 16.98 Bus Anylsl 27.40 AVERAGE MILES /GALLON - When Detach') 28.09 All Libraries Available FIG. 4 the AVE MPG button is depressed. the display indicates the average miles per gallon the vehicle has attained since HEWLETT ghP, PACKARD copper (or heavy aluminum) and make the last reset (up to 200 mpg). the contact edges are straight and CORRECT TIME (clock] - When the sure TIME button is depressed, the display H P healer All accessories at Account We are tranchisen smooth. indicates the correct time (in hours and minutes). The clock may also be used

. , .$140.00 HP -10 NEW $139.00 HP-27 .. to display ELAPSED TIME. HP -19C NEW 275.00 HP -29C NEW 156.00 Conversation piece HP -21 64.00 HP -80 235.00 AUTOCOMP comes with clear. illustrated HP -22 100.00 HP- 67 ...... 360.00 You probably have a number of poten- HP-25... 100.00 HP -91 260.00 instructions that make it easy for a do -it- to install. Equipment supplied HP -25C 128.00 HP -92 NEW . ... 500.00 tial conversation pieces lying around your yourselfer HP -97 599.00 includes the Speedsensor which simply workshop. Perhaps you have a surplus or screws onto the speedometer cable, and Also SCM. Olivetti. National Semiconductor Casio. Canon. the digital Flowsensor which easily installs Corns. APF. Sharp. Craig. Sanyo. Record -A -Call. and more burned -out PC board that's loaded with onto the fuel line. All at great prices! parts. Just clean it up, insert it in a slot

Programmable Video Game . 5129.95 wood, or cover the games possible) cut in a block of SAVE $10 OFF REGULAR P' I M I 1-13 my" PA R C CaOAlso s 17.95 with clear plastic. board I tumid Watches! bottom of the Order now using the coupon below and save $ r off the regular list price of 5129.50. A one o WE WILL BEAT OR MEET ANY COMPETITORS' PRICE IF HE HAS I made one from a surplus 3 X 4-inch limited warranty is p ovided. in factory cartons year 4 MERCHANDISE ON HAND. All units shipped original loaded with IC's, tran- , with accessories according lo manufacturers' specifications In Calif. PC board. It's +S call (2131370-5795 or CALL(800) 421 -0367 (other than CA). Above sistors, LED's, coils, resistors -all the prices are for cash only. Credit card prices differ. BankAmmleard/Vlsa & Mager Charge accepted. Send money order. Pers. ck (2 wks to burned -out and useless parts we could clear): In CA add 6% sales tax. Add $3.50 min. shipping charges. Send mail orders to DEPT find. It finally ended up as an unusual SpaceKom, Inc. WE SHIP AIR on request. Subject to availability. 44Q4 WRITE OR CALL FOR FREE CATALOG RE-L. paperweight, with some tall tales at- 212 E. Gutierrez St./ otc tkWILSHIRE -2 STORES - HAWTHORNE blow Santa Barbara, / J$o`' CALL tached to it. It would undoubtedly r CA 93101 sky high if power were applied to it. ; eArprilses However, technical and nontechnical folk aus,Nts, ..Orion, alike have believed the most fantastic / / + a 16611 Hawthorne Blvd_ Lawndale, Ca. 90260 things that it would do or "used to do / 5 ,.os0 \213l 370-5795 (800) 421 -0367 O c? ,,a a` 05° 4' o before it went bad!" R -E / INFORMATION CARD CIRCLE 49 ON FREE INFORMATIC N CARD CIRCLE 103 ON FREE 71

www.americanradiohistory.com computer corner

Z_80 An in -depth look at the pin -out of the Z -80 IC and giving control back to the CPU. The HALT output indicates that the the Z -80's timing. WILLIAM BARDEN, JR. CPU has executed a halt instruction. An

LAST MONTH'S COLUMN COMPARED THE AO NMI, I/O interrupt or control -panel ac- RESET 26 30 Z -80 with the 8080 and discussed the Z- RFSH 28 31 tion must occur before normal operation A2 MREQ 19 32 80's architecture. Now let's take a look at A3 can resume. The halt instruction would 21 33 the pin -out of the Z -80 IC Z -80's A4 and the WR 22 34 normally be used either to wait for an AS timing. WAIT 24 35 A6 interrupt or to halt program execution 27 M1 36 Al IORQ 20 37 16 -BIT for an end -of- program condition or an A8 ADDRESS Z-80 pin -out INT 16 38 AD BUS error condition. NMI 17 39 Figure 1 shows the signal pin -out of A10 BUSRQ 25 40 All the Z -80 IC. The Z -80 is implemented in BUSAK 23 1 Z -80 timing Al2 HALT 18+ 2 a 40 -pin dual in -line package. The 16- A13 Execution of any instruction by the Z- Z - 80 MICRO 3 line address bus is designated A15 PROCESSOR 4 A14 80 CPU consists of a number of machine A15 through AO. The external data bus is D7 6 5 cycles, each (designated M) consisting of DO. +5V 14 through A single -phase TTL -level UND 15 several basic clock cycles. The first ma- clock input is at the ß pin. The input 12 B frequency is 8-BIT a nominal 2.5 MHz, produc- LO R, N 7 DATA BUS LOAD REGISTER ing minimum instruction times of 1.6 9 R (A, B, C, D, E, H, LI LO OPERATION N 10 WITH VALUE CODE µs. 07 N The RESET input initializes the CPU 13 FIG. 1 8 BITS OF VALUE by zeroing the program counter, setting OP CODE TO BE LOADED the I and R registers to zero, disabling is is signal high, interrupt I I the accepted I i interrupts by resetting the interrupt and the IORQ signal is brought low

enable flip -flop, T1 I and setting interrupt I during the MI signal to indicate an inter- T2 T3 I T4 I T1 I T2 I T3

mode 0 (to be discussed in a later rupt acknowledge to the interrupting I/O MIIFETCH OF M2 (MEMORY column). Setting this signal to a zero device. LO OP CODE) READ OF NI logic level is the normal method to reset Input signal NMI is triggered by a EXECUTION OF LO R, N= 7 CLOCK CYCLES OR the CPU. negative -going edge. The nonmaskable 2.8ys FOR 2.5 MHz CLOCK The RFSH (refresh) output informs interrupt it produces cannot be disabled FIG. 2 external logic that the contents of the R and is recognized at the end of the

counter is now on the address bus and current instruction. Once received, NMI 1.6 µ s that a refresh read of the dynamic memo- causes the CPU to restart to location 4 CYCLES- ries be by can done means of the MREQ I 006616 (described in a later column). I I signal. Input BUSRQ (bus request) requests The MREQ, RD and WR signals are the CPU to give up control of the address

TI I T2 I T3 T4 tri -state outputs indicating a memory bus, data but and control signals. When I

request for a read or write to the CPU. the CPU responds by bringing output M1 The address bus holds a valid address for signal BUSAK (bus acknowledge) low, CPL INSTRUCTION the memory operation when MREQ is those lines can be controlled by external (FETCH OP CODE AND ONE'S COM- low (zero logic level), and either RD or logic for DMA (Direct Memory Access) PLEMENT A REG- WR is low. The WAIT signal is brought or other uses. When the external device is ISTER down to a zero logic level by the memory finished, it brin}fs up the BUSRQ line, FIG. 3 after MREQ. The WAIT signal remains low until external memory is finished, LD A, NN (LOAD A REGISTER enabling the CPU to interface to slower WITH CONTENTS OF speed memory. MEMORY LOCATION NN) When output signal MI goes low, the LO OPERATION BYTE 1 BYTE 2 CPU is in the CODE operation code fetch cycle 1 of instruction execution. If both MI and

IORQ are low, an interrupt acknowledge 8 BITS OF VALUE TO cycle is in progress. OP CODE 5.2 is BE LOADED A Output signal IORQ indicates that the address bus holds a valid I/O address for

I I an I/O read or write (input- or output - type instruction). If M1 is also low, an interrupt acknowledge cycle is in pro- I I T4 I I ---Ti 12 T3 I T2 T3 TI T2 T3 Ti T2 I T3 gress. M1 (FETCH AND Ti M2 (READ M3 IREAD M4 (READ OF Input signal INT is an interrupt re- DECODE OP CODE) BYTE 1 BYTE 1 OF CONTENTS OF ADDRESS) ADDRESS LL ANTOD TRANS- quest. If the interrupt enable flag IFF is FER A) enabled (by software) and the BUSRQ FIG. 4 72

www.americanradiohistory.com chine cycle (MI) is always an operation Federal suit planned against importance of Citizens band rules ar d reg- code fetch and decode. Figure 2 shows Virginia radar detector laws ulations. The show, entitled "10 -4 Uncle Ct arlie," the execution of the simple LD R,N A New Hampshire resident's wife was violating features such CB characters as Rkin ?stone instruction, which loads CPU register R recently arrested in Virginia for -radar laws. Bill Edwards, a Cowboy, Earthmama, Bucketn-cutn and with the eight -bit data value in the that state's anti Hillsborough, NH, engineer and ad manag- others. Included in the program are 72 instruction. er, is so incensed over what he deems to be slides, a 10- minute audio tape cassette, a various instructions in the Z -80 The a violation of due process that he plans to script and a question- and -answer be ok de- cc take anywhere from 4 cycles (1.6 As) to file a federal class- action suit against the signed to take care of the more nmon 20 cycles (8 µs), depending on the length state of Virginia. CB questions. The program can te pur- and operations of the instructions. The Apparently, no other laws had been vio- chased from National Audiovisual (:enter, , Order simplest instruction is one in which only lated. His wife not only had her radar General Services Administratio' Section, Washington, DC 20409. Tho slide - the op code was fetched from memory detector confiscated but was even required show package costs $15.00. and the operation of the instruction could to supply the tools to remove it. No anti - radar law exists in New Hampshire. be completed during the M I cycle. An The suit will charge violation of interstate example of this would be the one -byte commerce laws and federal preemption as the contents of IHF has big plans for the futurs instruction to complement well as seeking the return of all confiscated The image and the future of tho I -stitute the accumulator register CPL. (See Fig. radar detectors seized during the two -year of High Fidelity (IHF) are both char ging- 3.) The one's complement could be com- period of Virginia's anti -radar laws. Since for the better, thinks Bernie Mitchel presi- pleted in the four clock cycles of T1 (1.6 approximately 5,000 such detectors have dent of IHF. Some of the changes envi- µs). been taken from out -of -state drivers during sioned for IHF are: regularly scheduled this period, at an estimated cost of $100 Loading the A register with an eight - meetings for manufacturers to discuss each plus an average $100 fine per detec- bit operand from memory requires a problems and exchange views; belts. com- tor, Virginia could stand to lose a million fetch (memory read) of the op code for munications tools to "sell the procuct" to dollars in damages alone, if the suit is the load operation, two memory reads of potential buyers; and last, but n.)t least, a successful. the memory address within the instruc- major trade show for all hi -f manufac- tion, and one memory read of the oper- turers, called the IHF Show, to be held in May, 1978. and, a total of four machines cycles or a FCC cartoon show sends a big 10- President Mitchell is very erthusiastic total of 13 clock cycles (5.2 Ms). (See Fig. 44 to all CB'ers about the trade show, which will f omote 4.) For those not in the know, "a big 10 -44" the industry to potential and existing retail- All executive times might be length- is CB lingo for "I've got a message for ers. Not one but several seminar5., we plan- was interfacing to a slow ened if the CPU you." In this case, the Federal Trade Com- ned, covering such diverse topics a:: adver- memory. mission's message is a 10- minute cartoon tising, accounting problems, service prob- The next column in this series will slide- and -sound show aimed at schools, lems, store displays, market ressa-ch and discuss the different types of instructions clubs, and other interested associations; countless other ideas to help hi -fi dealers associated with the Z -80. R -E the purpose: to acquaint everyone with the share in the industry's growth.

Accuracy like a VTVM Convenience like a VO NEW BATTERY -OPERATED FE SOLID -STATE VOLT -OHMMET Easy to build KIT $41.85 -116K

Factory-Wired & Tested $56.12 =116W Now you can get all the benefits of a VTVM (laboratory accuracy, stability and wide range) but with its drawbacks gone: A Platt tool case no plugging into an AC outlet, no waiting for warm -up, no bulkiness. New Field Effect Transistor (FET) design makes won't fall apart at the seams possible low loading, instant-on battery- operation and small size. Excellent for both bench and field work. because there are no seams. Compare these valuable features: Unlike other tool cases. the pockets on a Platt Pallet are High impedance low loading: 11 meg- ohms input on DC, 1 megohm on AC a - EMC line molded without any seams, stitches or rivets to form one 500 -times more sensitive than a standard Send FREE catalog of complete 20,000 ohms -per -volt VOM Wide-range and name of nearest dish lb' :or. piece unit. It's practically indestructible. RE-12 The case itself has that same rugged construction. It comes ¿ersatility: 4 P -PAC voltage ranges: 0 -3.3, 1200V; 4 RMS AC voltage ranges: 33, 330, Name in either tough. lightweight ABS Thermoplastic, rich looking ) -1.2, 12, 120, 1200V; 4 DC voltage ranges: expanded vinyl or a combination of both. ) -1.2, 12, 120, 1200V; 4 Resistance ranges: Address Platt also has rugged hardware. Like an aluminum rim for -1K, 0.100K, 0-10 meg., 0.1000 meg.; 4DB ranges. -24 to +56DB. extra strength. Steel core handles. And tough brass locks. City Sensitive xasy -to -read 41/2" 200 micro - Inside there are compartments for larger tools, parts boxes meter. Zero center position avail- amp lip a and testing equipment. And multiple lid pockets for paper able. Comprises FET transistor, 4 silicon State m 2 Meter tran- () and order hooks. transistors, diodes. and m sistors protected against burnout. Etched Besides having a tough case Platt panel for durability. High- impact bake - has a tough 5 -year guarantee on both lite case with handle useable as instru- EM mIA the case and pallet. ment stand. Kit has simplified step -by- ELECTRONIC MEASURE 7J step assembly instructions. Both kit and Pat. \o. 3.sslt'x5 and industry. 625 Broadway, New ye Cases for business factory -wired versions shipped complete CO with batteries and test leads. 51/4 "H x 2301 S. Prairie Ave., Chic;' i. Hl. 60616 1312) 225 -6670 63/4 "W x,27/e "D. 3 lbs. V CIRCLE 37 ON FREE INFORMATION CARD 73

www.americanradiohistory.com SERVICE QUESTIONS nected right across the AC line (see three out of four outputs normal, the c atinued from page 67 Fig.l). "source" must also be good. (In fact, one From the symptoms, I'd say that you normal output is enough.) FUSE BLOWS INSTANTLY have a shorted degaussing coil. That's the This leaves you with only the focus The 3 -amp line fuse blows almost in- only other thing in the circuit, except for circuitry. You can check the focus trans- stantly when I turn on this Penncrest that 270 -ohm resistor (which is probably former by simply disconnecting it from 2852. After making the regular tests, I burned up also). Incidentally, this resis- the flyback. This is a "tosser," and if it's clipped the posistor in the degaussing tor is listed under "Resistors" in the open, focus voltage will go to about 5 kV circuit. Now the set works fine! There Sams Photofact 1319 -3. and stay there; no variation. aren't any shorts in the degauss circuit; I You can, however, operate the set The crystal ball says that the most put in a new posistor, and the fuse blew without this circuit. The same basic cir- likely thing here would be a bad focus again. What gives ? -D.B., Fremont, NE cuit is used in some other makes. The rectifier or no heater voltage on it. For a " Posistor" is not a standard name! clue, of course, is the degaussing -coil quick check just tack in a solid -state Translation: it's a positive- temperature connection right across the AC line. The focus rectifier, such as RCA -SK -3066, coefficient thermistor. As it's used here, device used here must be a positive - Sylvania ECG -118, or Raytheon RE- it must start at a very low resistance (13 temperature coefficient thermistor, 167. (If this brings back the focus volt- ohms cold) and then go away up in resis- which goes to a very high resistance in age, leave it in; mount it on a terminal DEGAUSSING only a short time. strip so that it won't arc to COILS anything. I've done this in quite a few sets, and it works POOR FOCUS like a charm.) Final check: Run the set HOG I replaced the flyback and some tubes for about five minutes and then turn it off in an Admiral 24A2 chassis. I got a fine and feel the 1V2. If the tube envelope is color picture on my test jig. I took it home stone cold, it isn't getting enough heater 2700 and the picture was blurry, dim, and I current. ON-OFF couldn't get good focus. I figured it out. SW TO POWER SUPPLY My test jig has an electrostatic -focus pic- RESISTOR BURNS UP 120VAC --0 ture tube! My focus voltage reads only l'tr having problems with this Zenith IN about 600. High voltage and boost are 14Á9C50. The 560-ohm resistor in the FIG. 1 1 right on the nose. I changed the focus horizontal blanking circuit keeps burning tance within not more than a second or transformer, but no luck. What am I over - up. The DC voltages on the horizontal two. The actual heat resistance is un- looking?-L.P., Osceola, IA blanking transistor are all far too high. I known but it has to be pretty high, since One key fact: The flyback drives the am reading 40 to 50 volts P -P on the it must reduce the current through the high voltage, horizontal sweep, yoke and diode. The set works but has a drive line degaussing coils to practically zero in the focus circuit. This drive is the 5 kV+ on the left and a slight foldover -L.H., normal operation. These coils are con- pulse from the 6DQ5 plate. If you have Enid, OK Your voltages are all far too high, especially the pulse voltage on the blank- ALDELCO ELECTRONICS COMPANY ing circuit. This should be only 3 to 4 catalog NEW IMPROVED DIGITAL ALARM CLOCK KR 0.5 LED Display 12 hour format volts P -P, and you're reading a 50 -volt FREE Snooze Feature 12: I 1:1 Elapsed Timer pulse. This much overload would make of over Simulated Wood Grain or Black Leather Cabinet $24.95 12 or 24 Hour Clock Kit. Similar to above but without Alarm or that resistor burn up. Timer features Only $23.95 Crystal Time Base Kit for 12 Volt DC use 4.95 Check out the small winding on the COMBINATION FREQUENCY COUNTER CLOCK KIT. D.3 LED flyback. The black wire should be the 2000 Display. .0001% accuracy. 12 or 24 Hour Clock uses 8 AA Nlcad batteries (not supplied) S 99.95 ground, and I bet you'll find it open. This small tools, Assembled Unit 139.95 110 Volt AC Power Supply & Battery Charger 5.95 should be the only thing that would raise measuring VOLTAGE REGULATORS CLOCK CHIPS the pulse amplitude. TO220 Package 5313 $3.49 instruments, 5314 3.95 PEPositive Neglatii5 5316 3.95 5375 3.95 TUBE CAUSES HIGH -VOLTAGE and supplies 7805 7905 CT7001 8.95 7808 7906 PROBLEMS 7808 7912 ELT - LOGIC PROBE KIT 7812 7915 DIGIPEAKE -A $11.95 I'm having difficulties with an RCA °.;.COL 7815 7918 ' LM309H 51.10 100' Spool Green CTC- 52XAC. I found a bad 31LZ6, and ....DRILLS LM309K 1.10 Wire Wrap LM723 .55 Wire 2.75 some bad 6GH8's. Now a dim raster ..FILM LOADERS... Wire Wrap Tool 44 WSU30 5.95 comes on and goes off at short intervals. PS. . .PAGES. ..GRAVERS MA1003 National AUTO or The bias on the 31LZ6 is only . . .GRINDERS.. .HAMMERS.. grid -35 1,.s BOAT CLOCK MODULE SPECIAL $21.95 With Module Three Push Button Switches AND choice of Blue, volts of volts. waveform INCLINOMETERS. . .JACKS. instead -50 Grid Green, or Amber Filter. KNIVES. .. LATHES. ..LEATHER ` is only 200 volts P -P instead of the speci- WOW LOOK AT THIS JUMBO AMATEUR TV CONVERTER ETTES. .. LOUPES. ..MINIATURE RED LEDS Covers 420 to 450 AM TV fied 250 volts. -S. V., Falls Church, VA 11 for $1.00 BAND. Works on unused TOOLS.. .METRIC TOOLS...MULTI, ,. Green. Yellow or Orange LEDS Commercial TV Channel This sounds like our old problem with 5 for $1.00 KIT ONLY $39.95 TESTERS. , .NEGATIVE FILES.. FND 70 CC 0.3 Display LED .49 ASSEMBLED $49.95 the 31LZ6 tubes. Try each one after the FND 500 CC 0.5 Display LED NIPPERS...OILERS...PIN . VISES.. .89 BLINKEY- FLASHER -TIMER other; we used up three before we found PLIERS. ..PROBES...RIPFLERS... CLOCK FILTERS 2'/. o 5'/." KIT Red, Blue, Green or Includes 555, PC Board the right one. The key is in the flattening Amber .60 ea Parts & Instructions $2.50 SCISSORS. . .SNAR ES._SOLDER. of the peaks of the 31LZ6 grid wave- ING SUPPLIES. . .TEST INSTRU ACCUKEYER KR. Uses TTL, Includes IC's. sockets, Speaker, PC Board, Instructions and all parts ONLY $19.95 form. MENTS... TWEEZERS. .. VIEWERS MEMORY KIT. Matches above & other accukeyer kits ONLY $19.95 (Feedback: very much! The ...VISES... WRENCHES... "Thanks ADH'. 011 ABRASIVES... VARIABLE POWER SUPPLY KITS. .5 Amps 5-15 Von DC $6.95 third 31LZ6 did the trick. The grid wave- co add $1.00 per kit shipping .5 Amps 12 -28 Volt DC 6.95 G. ..BOOKS form was flattened, but the cathode cur- *E'lll.1111/:,, Visit Our Store. Hours 9:00 AM to 8:00 PM Mon. to Fri. Sat. 9:00 LIMATORS AM to 2:00 P.M. Phone Orders accepted. Visa & Master Charge rent didn't seem to creep up as much as ADD 5% FOR SHIPPING. ORDERS UNDER $10.00 add $1.00. 1952 1911 4L EPDXIES. Foreign Orders add 15% shipping (Except Canada & Mexico) send you said. I see that RCA now rec- Certified Check or Money Order in USA funds. -/ q` .CALIPERS. ommends replacing all 31 LZ6's with boo`, S`ò ALDELCO 36CM6. ") National Camera 2281R Babylon Turnpike, Merrick, New York 11566 2000 West Union nepr GBC be. 516 378 4555 Thanks to Sam Yoder, CET, Falls Enyteweed, Core, U.S.A. 10110 Church, VA, for this information. CIRCLE 7 ON FREE INFORMATION CARD CIRCLE 76 ON FREE INFORMATION CARD

www.americanradiohistory.com DOUBLE ANALYST TROUBLE 19V8 TUBE SUBSTITUTE this shouldn't be too hard to do (The The color popped in and out, then I'm working on a Philco radio, model heaters are on pins 4 and 5 ott both, finally went out entirely, on my B &K No. 53 -958, that uses a 19V8 tube. I can't which saves just a little time!) 1077 Analyst. The black- and -white bars find anywhere. I can't even find the base on the screen showed up but no colors. connections in any of my data. Can you You suggested replacing the crystal, help me find a substitute ? -G. S., Wash- PEAKING -COIL SUBSTI- fE which brought the color back. However, ington, DC. I need a replacement for a E rad ford the color was still intermittent. Checking Any time you need data on an obsolete part -a 50-ph peaking coil. The 7F et num- around, I found a 220 -pF capacitor on tube, check the GE manual, Essential ber I have is TL T 500 -999. Can yc u help? - the grid of the 6GH8 color oscillator tube Characteristics, from the 14th edition on. D. S., Kearny, NJ. that was changing in value as the heat of The manual shows a 19V8 tube that has My J. W. Miller Company Catalog the tube warmed it up. electrical characteristics identical to No. 175 lists 16 companies 'h:tl have Thanks to John Conti, Galveston, TX, those of a 19T8 tube, which is still avail- built sets under the Bradford n Intl. This for the feedback. able. However, the 19V8 tube has a 9AH part number is a Matsushita la:. num- OUTPUT TUBES BURN UP base, and the 19T8 tube has a 9E base. ber, and the exact replacement is Miller will R -E I work in electronics but not in audio! In So, you have to rewire the socket, but 74F-475A1. this stereo amplifier, the 7189 output tubes keep overheating. The schematic doesn't give any DC voltages. There's something I don't know! Do you know what it is ?-R. J., El Dorado, AR. I think so. I've been snakebit by the same problem in a different amplifier. SERIES 6000. car stereo Look at the control grid circuit of the 7189 output tubes. Follow the grid return speakers, the only air - back to the DC power supply, and you'll find a little negative voltage supply of sealed convertible mount something like -20. This voltage must be applied to the control grids of the 7189 on the market today tubes to make them work in Class AB,. If you lose this bias, the tubes will take far too much current and blow up. In the unit I had, this bias supply had been shorted where the wire went around the sharp corner of a ground terminal.

IBearcatÌ111Ü Scanneri

WEal. Surface mount Flush mount

We know that sometimes you can't If there is room in the trun fou cut a hole and mount a speaker are not at the mercy of ho ver where you want it in your sports the trunk is acoustically fi- car. truck, van, hatchback, station gured. The SERIES 600 M air- wagon, RV, etc., etc., etc. That's suspended sealed enclosur n- what makes the KRIKET" trots sound better than a -her SERIES 6000 car stereo product on the mar:cet tod speaker unique. You can mount it The result is sound so clear an $289. on any surface. And it's patented The Bearcat 210 super synthesized receiver and brilliant, you'll think J're WORKING WALL'; sound baffle scans and searches 32 -50, 146-174 & listening to a home stereo s ker 416-512 MHz. without expensive crystals. insures sound reproduction un- now on 24 system valued at hundreds dol- Order our hour toll -free credit matched in performance, quality card order line 800 -521 -4414. In Michigan lars. Yet KRIKET® speak are and outside the U.S. call 313-994 -4441. Add and value. $5.00 for shipping in U.S. or $8.00 for air sold at a fraction of that co UPS to west coast. Charge cards or money orders only. Foreign orders invited. For additional information, write: Communi- innovators in great autosound cations Electronics, P.O. Box 1002, Dept. 503, Ann Arbor, Michigan 48106. als ACoustic Fiber Sound Systems UP' ' p Indianapolis, Indiana 9 Jusi say charge it, Which carde Kriket Ills CTM I10gomuor

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www.americanradiohistory.com IT'SNEW. RE TESTS ONKYO TX -8500 worst internal heat dissipation condition) continued from page 57 without failure. This test is required by the Federal Trade Commission, and we used the FSDIGITAL lower impedance loads without the thermal Results can be compared with the manufac- protection circuits cycling off during the turer's published specifications elsewhere in tests. Fil PUSHBIJ1TON. this report. For reasons which remain unclear, Signal -to -noise measurements were made the 50 -dB quieting level in stereo was consid- using an IHF "A" weighting network, simply erably poorer than specified, with 55 pV (40 to compare our results and those of the manu- dBf) of signal required to achieve quieting. facturer. Even when measured without Mono measurements, on the other hand, all weighting, hum -and -noise was quite low for a equalled or exceeded published specifications. preamplifier -equalizer section in a combina- The dial -calibration discrepancy was uniform tion receiver. over the whole dial spread; this indicated that Bass, mid -range and treble control ranges the dial pointer was wrongly positioned rather are shown in Fig. 1 while response with and than a misalignment of the FM circuits them- selves. Signal -to -noise ratio in mono was ex- cellent at 74.0 dB and satisfactory in stereo at 65 dB. Carrier suppression was a more than adequate 60 dB, so you are not likely to encounter any beats when recording FM from the recorder outputs. Amplifier measurements Table II lists measured results for the amplifier section of the model TX -8500. CB/RF Power output at all frequencies was signifi- cantly higher than claimed, for 8 -ohm loads, with 118 watts -per- channel available at the GENERATOR. difficult 20 -Hz extreme for the rated 0.1% harmonic distortion level. The fact that Onkyo Keyboard entry for instant lists a power- output rating for 4 -ohm opera- fingertip selection of all 40 tion and pegs it as high as they do suggests that any thermal problems have been success- channels. fully solved in this design, for such a rating Phase -locked -loop frequency implies that the amplifier can deliver 50 watts control for crystal stability for one continuous hour into 4 -ohm loads (its -}5 ppm ( ±.0005 %a). LED channel display. 455Hz IF output -with front

panel socket for extra I F crystals. Double shielded for ultra low RF leakage. Metered precision attenuator for signals down to O.3,1V. Metered modulation for precise output adjustment. SSB test function pushbutton +'w+-¡.-- operated. `' Noise generator for ANL and ,....-- noise blanker tests built -in. Every day more people discover that PAIA's GNOME, the original micro- RF protected up to 5 watts synthesizer, is the most versatile, cost for 1 minute. effective special effects device on the .,..r- 2 year warranty. market today. Modern compact size The Gnome has two envelope generators (one with repeat for cyclic effects), VCA, 5 (81/4 "w X 7 "h X 91/2"d). VCF and VCO. Use alone with it's built without the low- and high -cut filters, over a In stock at your Hickok in ribbon controller or modify to interface 20 -Hz to 20 -kHz range, is shown in Fig. 4. distributor. to guitar, electronic piano, polytonic Figure 5 shows multiple sweeps of frequency keyboards, etc. at different master volume control settings MODEL 266 495°I) Best of all, the Gnome is only $48.95 with the loudness circuit activated, and the in easy to assemble kit form. Is it any usual bass and treble compensation increases The latest addition to tI,. HICKOK wonder why we've sold thousands? as the volume level is reduced. Comm/ me ( ) Send the GNOME MICRO-SYNTHESIZER Kit Summary the full line of professional CB (548.95 plus $2°° postage Service instruments A brief summary and overall product anal- (1 Send FREE CATALOG m ysis of the receiver are given in Table III. The name: accompanying comments suggest that this On- kyo receiver offers an excellent amplifier sec- address: HICKOK tion that more than meets its specifications. city: state: zip: sounds good and has just about all the controls the value innovator and flexibility one would want in an integrated BAC VISA_ MC_ cardes._ the does INSTRUMENTATION & CONTROLS DIVISION receiver. If tuner section not quite to: THE HICKOK ELECTRICAL INSTRUMENT CO Cut out & mail 14051843-9626 come up to the quality found in high -priced 10514 Dupont Avenue Cleveland. Ohio 44108 DEPT. 12- R separate tuners, the receiver's total price may 1020 W WILSHIRE,OKLAHOMA CITY. OK 73116 (2161541 -8060 TWX 810- 421 -8286 compensate for this imbalance. R -E CIRCLE N ON FREE INFORMATION CARD CIRCLE 70 ON FREE INFORMATION CARD

www.americanradiohistory.com West Virginia CB'ers to promote regional travel and provide tourists with emergency assistance A state travel promotion program, spon- sored by the West Virginia Governor's Office of Economic and Community Devel- opment and state CB associations, will involve local CB operators in providing Presenting tourists with both travel information and emergency assistance. your CB operators "have the reputation of being helpful when there is a highway emergency, so they are a natural source for portable says Barbara Jones of travel information," TF46 PORTABLE the Governor's Office. Since other states automatic are increasingly using CB'ers as goodwill SUPER CRICKET TRANSISTOR a FET TESTER ambassadors in travel promotion as well as solid state in emergency assistance, Ms. Jones per- ceives this trend as possibly becoming nationwide. The West Virginia program is called "CB Operation Latchstring." CB club members who participate will receive a certificate, a bumper sticker indicating their participa- tion in "Latchstring" and an information brochure. For travel information, a tourist merely tells local CB'ers to "Break 19 for Opera- PPÉÏ" tion Latchstring "; he is then instructed to switch to another channel so as not to tie up Channel 19. The assistance channel is Channel 9; the CB operator stays with the caller until help arrives. The emergency assistance program will involve mobile unit Now, nobody likes to be called a Job Hopper, but the new, patented TF46 Portabli! Super operators, base stations, REACT mem- Cricket can literally help you hop from job to job through solid state circuits faster than bers, base stations and West Virginia State any other transistor tester on the market today. For the first time you can automatically Police mobile units. R -E analyze 162,000 different transistors and FETs, in or out of circuit at any job location in the world. Here are four reasons why. It's 100% automatic. Connect the test leads any way you want right in circuit and rotate the large FREE! permutator knob until the Cricket "chirps ". Read any transistor or FET as Good or Bad on the meter with the patented phase- inversion automatic Cricket EDMUND test. It even identifies the transistor leads! It virtually thinks for you. SCIENTIFIC It takes no set -up information. and FETs the same simple S None at all. It tests over 162,000 transistors with u , ` ' C MO É Nj test, and can easily be used by a non -technical maintenance person. EECOPSS S Nj°p0. & 71/426., 000 It provides Leakage Gain tests EEM v GAIN 4 S VOS r. to completely analyze any transistor or FET. MpGN EEA"?GE The only portable tester that includes transistor Beta, FET Gm, and LAI leak- age checks to totally check all parameters, and catch troubles other m ss. 164 PAGE You can now test solid state circuits anywhere. CATALOG The TF46 is fully battery operated for the field, or AC operated for the bench Over 4,000 unusual bargains for science with the optional 39G90 Power Adapter. You know what else? TFe TF46 and industry. automatically turns itself off after 10 minutes of testing in the field to save In -stock supplies for engineers, experi- menters, research labs, hobbyists, etc. the batteries. and save buy with com- Order direct - All these features, at $45 less than the earlier model TF30 Super Cricket that +vas AC plete confidence ... every item carries it. local Full Line Promotional Dis:ributor the famous Edmund 30 -day money -back operated only. Hop to Call your Sencore guarantee. or order your TF46 Job Hopper with the coupon below. Simply mail this coupon for the newest tatti Edmund catalog. OM Iti 8i 8i ti ti ti 8i ti ti ti I= ti ti Ri ti ti ti ti ti ti 1 ti Ii 3200 Sencore Drive, Sii ux Falls, RUSH LATEST FREE EDMUND CATALOG So. Oak. 57107 (60íi} :139 -0100 In Canada: Superior E ectronics EDMUND SCIENTIFIC CO. Dept. EH2O, Edscorp Building I WANT TO BUY IT. Send_TF46s NAME: Barrington, N.J. 08007 to me at $195 each. COMPANY: Check /MO enclosed. Send C.O.D. Name Also send: STREET: Address PA202 Power Adapter $9.95 CITY: I City I _39G85 Touch -Test Probe $10.00 I WANT TO TRY IT. Have my nearest State Zip STATE- ZIP: I - Sencore distributor bring the TF46 to me. L.------a- - .... J SEND FULL SPECIFICATIONS. PHONE: CIRCLE 52 ON FREE INFORMATION CARD CIRCLE 4 ON FREE INFORMATION CARD

www.americanradiohistory.com new products

More information on new products is available from manufacturers of items identified by a Free Information number. Free Information Card follows page 98.

WIRE CUT AND STRIP TOOL, model ST-100, Housed in rugged lightweight high- impact plastic quirements are +8 volts unregulated at 170 mA TM for easy and clean stripping of wires for wire - case, complete with snap -in NiCad Battery-Pak (typical), 250 mA (maximum); and + 16 volts wrapping electronic applications. Designed for and AC adapter charger. Price: $175. - Triplett unregulated at 85 mA (typical). Price of the model maximum efficiency, it easily stores in a belt Corp., Bluffton, OH 45817. CT -1, $395; CSR1 software, $35.- Computalker CIRCLE 86 ON FREE INFORMATION CARD Consultants, Box 1951, Santa Monica, CA . 90406. 11 "T- o,d.STR SO TOOL AMMETER, Ampak 705A, measures 1 -8 Foie WIRE-WILIP Y.\'4 model CIRCLE 88 ON FREE INFORMATION CARD amps DC and 1 -400 amps AC with 3% accuracy without breaking circuit or changing tongs or COMPUTER TERMINAL KIT, model CT -64, can shunts. All DC waveforms, including SCR circuits, be used with any 8 -bit computer to display 128 can be checked. Clamp -on unit has a meter ASCII characters in 16 lines of 64 or 32 charac- ters. Unit features scrolling or page mode, 32 control character decoding, selectable printing,

holster, or tool kit. The hardened steel cutting blades, insulated handle and sturdy construc- tion of the tool insure long life. The stripping blade is easily replaceable. Available for wire from 20 to 30 AWG. -O.K. Machine and Tool Corp., 3455 Conner St., Bronx, NY 10475 remote from the tongs for easy readings. Power supplied by series 133 mercury cells included. CIRCLE 85 ON FREE INFORMATION CARD Comes in heavy -duty carrying case. Price: and character or word highlighting. The model $195. -Pacer Industries, Inc., 704 E. Grand VOM, provides model 3300, is a five -function, 22-range Ave., Chippewa Falls, WI 54729. CT-64 full cursor control, home -up and unit that combines portability with precision. A erase, erase to end of line or frame, cursor on /off, CIRCLE 87 ON FREE INFORMATION CARD 0.3 -inch high LED readout provides extra reada- screen reversal, solid or blinking cursor, and end - bility. The five- function, 22 -range single selector- SPEECH SYNTHESIZER, model CT-1, is a high - of -page beep signal. Kit comes complete with quality voice generator that is S-100 bus- compat- keyboard, power supply, 110 -1200 Baud inter- ible and controlled by nine acoustic -phonetic face, and case. Also available is an optional 12- parameters. Programming can be accomplished MHz monitor, model CT-VM. Prices: Model CT- in different ways depending on speech quality 64, $325; model CT-VM, $175.- Southwest desired and the amount of memory available in Technical Products Corp., 219 W. Rhapsody, the computer. The CT-1 can be operated directly San Antonio, TX 78216. from memory- stored parameters, with a storage CIRCLE 89 ON FREE INFORMATION CARD requirement of 900 bytes per second of speech. The result is highly intelligible and natural-sound- DIGITAL CLOCKS, model 0100, model 0101, ing speech. Solid -State Technology KitsTM. The model 0100 alarm clock -calendar kit (shown above) features .8 -inch, 3%-digit LED display with AM /PM indica-

143.,1, . _14.14.

I - u au

The CT-1 can also be programmed using a range switch includes: .2 -600 VDC; .2 -600 VAC system of phonetic rules to generate the synthe- with a 10 megohm /100 pF input impedance on all sis control parameters from the phonetic -text AC ranges; low -power range of 200 mV 0 -2 input. Resulting speech is less natural but still megohms; high -power range of 2 volts, 0 -2 intelligible. megohms; AC /DC milliammeter at 0 -200 mA. The model CT-1 board measures 5'/. X 10- Basic DC accuracy of .5 %. inches and requires a block of 16 output loca- tor. Unit has 8- second time display and 2- second Unit measures 3 X 5% X 1%-inches, and is tions, 8 bits each, that can be relocated to any date readout. Can be connected either to radio or ideal for test bench and field measurements. hex boundary via a selector switch. Power re- 9 -volt battery. 78

www.americanradiohistory.com The model 0101 wall clock has a 2Y -inch, 6- digit LED display, visible at up to 50 feet. Time QUICK CHARGE IRON- and date are interchangeable, with constant time or date readout if desired.- Fairchild, Optoelec- tronics Div., 4001 Miranda Ave., Palo Alto, CA QUICK CHANGE TIPS 94303. CIRCLE 90 ON FREE INFORMATION CARD [S `TIP®Quick Charge Cordless TOOL CASE, model 615T, made of shatter- and Soldering Iron recharges in scuff -proof polyethylene, is ideal for carrying tools, parts and equipment. Comes with one- 3 -41/2 hours. Uses any of Wahl's 16 snap -in tips. Low voltage, battery powered, ground free isolated tip design.

=7554 I - rt It TUNER EXTENSION TIP =7571 - BEVELED TIP =2 =7573- TINNING TIP =5 Itr4- Lt It== rl=7579 - BEVELED TIP -3 =7589 - "V" TIP =5 Itl I .7592 BEVELED TIP =5 I - =7572 - BLUNT TIP =5 I_ttllll_ f'paw 7593 -- BEVELED TIP 4 =7577- CHISEL TIP =5

=7544 -MICRO SOLDERING TIP =7545 -FINE TIP =2 piece, solid, molded urethane pallet, handy for wall-hanging small tools next to workbench. Case Moe measures 15% X 12'/4 X 4'/4-inches and weighs =7555 - REGULAR TIP =5 =7598 -KNIFE TIP 3'/4 lb. -Platt Luggage, Inc., 2301 S. Prairie Ave., r Chicago, IL 60616. ' 7546 -HEAVY DUTY TIP =8 =7574- CONCAVE CENTERING TIP '5 CIRCLE 91 ON FREE INFORMATION CARD FREQUENCY MULTICOUNTERS, models 1910A and 1911A, can be used in a wide variety of appli- .7541 - CIRCUIT BREAKER TIP cations. Both units offer period, period average, WAHL CORPORATION and totalize modes, which allow many field and CLIPPER ORIGINATORS OF PRACTICAL CORDLESS SOLDERING Illinois 61081 (815) 625 -6525 "Manufacturing Excellence .~inch 1919" CIRCLE 75 ON FREE INFORMATION CARD

GTS -1O. OUR NEW MODEL OF GENERAL TELEVISION SERVICER. Here it is: Using all- silicon circuitry, the GTS -10 offers sfa ale operation over a wide temperature range. Digital IC's (33 of m) plus a voltage regulator IC produce outputs with a new dime n- sion in stability and freedom from interference. Five ay lal oscillators provide rock solid outputs that can be relied upor to lab measurements. The 1910A covers 5 Hz to 125 be on frequency, and since the GTS -10 needs only 10 wa to of MHz while the 1911A (shown) goes to 250 MHz. A power, it runs nice and cool. It's reliable - very reliable! variable trigger level and attenuator permit ac- curate readings even in very noisy environments. Flexibility ... versatility ... or whatever you want to cal . is

Inexperienced users will find that the autorange another strong point. For example, 4.5 MHz Sound Carrie r is feature (which prevents up and down ranging) all (RF, IF and Video). With 3.58 Mor or makes these instruments simple to use. The available at outputs model 1911A has a 50 -ohm impedance from 50 pattern you can check the color sync oscillator freque cy MHz to 250 MHz, useful in RF applications. Both without shorting the often difficult to find AFPC test Ix nt. multicounters have a basic 15 -mV sensitivity for Checking, cross -checking and adjusting purity using the unique reliable readings. Red, Blue Raster patterns is a snap. Use of other Both units can be ordered with either a 2 -ppm and Green is or 5 -ppm TCXO at 0-5° C; the aging rate is .3 patterns such as Vector, Color Bars, Hatchdots and Gray Qucd ppm per month. An optional rechargeable battery just as easy. pack gives four hours of continuous operation. The look is pretty snappy toc; - The cost of the model 1910A: $395; model 1911A: $495. -John Fluke Mfg. Co., Inc., Box human-engineered front panel \T.Tith 43210, Mountlake Terrace, WA 98043. big readable markings - all -rn fa CIRCLE 92 ON FREE INFORMATION CARD cabinet for rugged portability, spe _ JIly

RF shield -1 - HEX CODE CARD, model 8080, a 6.5 X 3 -inch designed to enhance aid to 8080 programming and debugging, con - clean compact size.

+ more. Write AmEI an ` Chou Tr :ry r-i"r ITT We'd like to tell you more -a whole lot Technology Corporation, 225 Main Street, Canon City, Colorado 81212. Our new, 6 page full color brochure gives details, specifi- cations and a feature comparison chart. Call us at (303) 2754 991 for same day shipment of MASTER CHARGE or VISA orders Only $349.00 -a moderate sum to invest in your future profits. ,end you can't lose with our 2 year factory warranty and 30) :Jay money back guarantee tains mnemonics and hex codes, with color - coded instructions to indicate which flags are The concept that is changing ATr continued on page 84 the course of TV servicing! II IL. AIAMERICAN TFCHNOLOGV CORPORATION 79 CIRCLE 42 ON FREE INFORMATION CARD www.americanradiohistory.com Advanced Electronics

There is no doubt television repair can be an interesting and profitable career field. TV repair, however, is only one of the many career areas in the fast growing field of electronics. Should your As an indication of how career areas compare, the consumer area of electron- ics (of which TV is a part) makes up less than one -fourth of all electronic equip- ment manufactured today. Nearly twice as much equipment is manufactured for the communications and industrial fields. career in Still another area larger than consumer electronics is the government area. That is the uses of electronics in such areas as research and development, the space program, and others. Just as television is only one part of the consumer field, these other fields of electronics electronics are made up of many career areas. For example, there are computer electronics, microwave and satellite communications, cable television, even the broadcast systems that bring pro- grams to home television sets. As you may realize, career oppor- go beyond tunities in these other areas of electron- ics are mostly for advanced technical personnel. To qualify for these higher level positions, you need college -level training in electronics. Of course, while it takes extra preparation to qualify for these career areas, the rewards are TV greater both in the interesting nature of repair? in the work and higher pay. Further- more, there is a growing demand for personnel in these areas. Unlike most other home study schools, CREI programs are devoted exclusively to preparing you for careers in advanced electronics. All of CREI programs are college level. And CREI gives you both CREI prepares you at home theory and practical experience in ad- vanced electronics. for broader and more advanced Unique Design Lab A unique feature of CREI training is its opportunities in electronics Electronic Design Laboratory Program, which trains you to actually design cir- plus offers you special arrangements cuits. It also helps you understand the theories of advanced electronics and gives you extensive practical experience for engineering degrees in such areas as tests and measurements, breadboarding, prototype construction, circuit operation and behavior, charac- teristics of electronic components and how to apply integrated circuits.

www.americanradiohistory.com career Training at Home

Only CREI offers this unique Lab Program. It is a complete college lab and, we believe, better than you will find in most colleges. The "Lab" is one of the factors that makes CREI training Book interesting and effective. And the pro- Send for this FREE fessional equipment in this program be- comes yours to keep and use throughout describing your opportuniti your professional career after you com- plete the training. and CREI college -level Engineering Degree CREI offers you special arrangements programs in electronics for earning credit for engineering de- grees at certain colleges and universities as part of your home study training pro- gram. An important advantage in these anG arrangements is that you can continue adv your full time job while "going to college" with CREI. This also means you can apply your CREI training in your work and get practical experience to qualify for career advancement. Wide Choice of Programs CREI gives you a choice of specializa- tion in 14 areas of electronics. You can select exactly the area of electronics best for your career field. You can spe- cialize in such areas as computer elec- tronics, communications engineering, microwave, CATV, television (broad- cast) engineering and many other areas of modern electronics. FREE Book In the brief space here, there isn't room to give you all of the facts about CREI college -level, home study programs in electronics. So we invite you to send for our free catalog (if you are qualified to take a CREI program). The catalog has over 80, fully illustrated pages describ- ing your opportunities in advanced elec- tronics and the details of CREI home study programs. Mail card or write describing qualifications to GI Bill Qualifications CREI pr. vranu approved You may be eligible to take a CREI col- CAPITOL are for trdn,ng of lege -level program in electronics if you RADIO veterans and are a high school graduate (or the true ENGINEERING servicente. 1 under equivalent) and have previous training the G.I ,3111. or experience in electronics. Program INSTITUTE arrangements are available depending upon whether you have extensive or McGraw -Hill Continuing Education Center minimum experience in electronics. 3939 Wisconsin Avenue Northwest Washington, D.C. 20016 Accredited Member National Home Study Council

www.americanradiohistory.com MATHEMATICS endeco NEW PRODUCTS ELECTRONICS Air continued from page 79 soldering & ENGINEERING MATHEMATICS ete..co desoldering affected. Back of card shows ASCII code chart, together with status word and register pair codes. ADVANCED MATHEMATICS equipment Single price: $2.95 postpaid. Discounts available These unusual courses are the result of on 10 -unit orders. - Tychon, Inc., Box 242, many years of study and thought by the Blacksburg, VA 24060. President of Indiana Home Study, who CIRCLE 93 ON FREE INFORMATION CARD has personally lectured in the classroom SOLDERING POLYMORPHIC MICROCOMPUTER, Poly 88 to thousands of men, from all walks of IRONS System Sixteen, comes assembled or in kit form. life, Unit's high -speed video display and alphanu- on mathematics, and electrical and meric keyboard lets you perform mathematical electronic engineering. Pencil style. Safety fight. Two heats - 20w and and analytical operations as well as enjoying a 40w. 6 tips. Unbreakable handle. 2 and 3 wire wide variety of video games. Cassette tapes You will have to see the lessons to neoprene cords. appreciate them! NOW you can master mathematics DESOLDERING and electronics and actually enjoy doing IRONS it! WE ARE THIS SURE: -you order your lessons on a money -back guarantee. Pencil style. Safety light. Some operate at 40w. idle In plain lariguage, if you aren't satis- at 20w. 8 tip sizes. 2 and 3 wire neoprene cords. fied you don't pay, and there are no strings attached. SOLDERING & Write today information DESOLDERING for more and KITS your outline of courses. provide permanent program storage. The BASIC Everyirmg needed software contains PLOT and TIME features You have nothing to lose, and every- to solder or de- based on video graphics and real -time clock; also solder or both. All thing to gain! included is a VERIFY function is in a handy lifetime metal that signals tape box with hasp. good before another is loaded. Also included are The INDIANA scientific functions, formatting options, string ca- See your distributor or write.. . pabilities, and a program library. Po /y 88 System HOME STUDY INSTITUTE Sixteen: $2250; kits start at $735. -PolyMorphic P.O. BOX 1189 Enterprise Development Corp. Systems, 460 Ward Drive, Santa Barbara, CA 93111. PANAMA CITY, FLA 32401 5127 E. 65th St Indianapolis IN 46220 PHONE 13171 251 -1231 CIRCLE 94 ON FREE INFORMATION CARD

CIRCLE 9 ON FREE INFORMATION CARD CIRCLE 2 ON FREE INFORMATION CARD DIGITAL MULTIMETER, model270, is a 3 %- digit, battery- operated kit that provides 21 -range AC/ DC current, voltage and resistance measure- ments. The 0.5 -inch LED displays are readable to "My father built this Sehober Organ for me!" You'd be proud to buy her an organ this "ready- made" organs...easily comparable to good...but how would you feel if you'd also others at twice the price. Kit costs range from built it? Its a special kind of satisfaction. The $650 to $2850 for all basic components, and gift of a lifetime of magnificent music, crafted you can purchase it in sections to spread with your own hands! costs out...or have two -year time payments. And you can do it! You need no prior When you've completed the basic organ, electronic or mechanical abilities. Just the Schober offers a full complement of acces- capacity to follow instructions. Every step is sories...plus complete organ playing courses! clearly detailed, every component is supplied. People have been building Schober Electronic You'll find the assembly process as enjoyable Organs for their daughters, sons, wives, hus- as the music which follows! bands...for themselves...for 20 years now. Join And what music! For this is a truly fine the thousands of delighted Schober people. instrument you will build. Far superior to most You can have all the details, without cost 1999. Instrument has 0.5% DC accuracy, 10- or obligation. Just send the coupon for the megohm input impedance, low- voltage drop in all fascinating Schober color catalog (or enclose ranges. An overrange indicator flashes automat- $1 for a record that lets you hear as well as ically when input exceeds value of range selected. see the quality of Schober). Why not clip it Unit comes with test leads and stand; batteries right now, before you forget? not included. Optional AC adapter, model BA -27, is available. Suggested kit price: $79.95; factory assembled: $109.95; model BA -27: $9.95. -Eico Electronic Instrument Co., Inc., 283 Malta St., Brooklyn, NY 11207. CIRCLE 95 ON FREE INFORMATION CARD imeawmws so TV FIELD STRENGTH ANALYST, model 5001, can be used as a field- strength meter that tunes The &Adel Organ Corp., Dept. RE -169 to all UHF and VHF channels. A three -position 43 West 61st Street, New York, N.Y. 10023 attenuator switch allows signal measurement Please send me Schober Organ Catalog. from 0- 100,000 V. Meter scale is calibrated in I Enclosed please find $1.00 for 12 -inch L.P AV and dB. Used as a TV analyst, unit can substi- record of Schober Organ music. tute the VHF or UHF tuners or combination of the two for any 41 -MHz TV receiver, and can also ' NAME check IF and AGC. ADDRESS The model 5001 is AC /DC- powered, with a 300 -ohm input for home use and a 75 -ohm input 1 CITY STATE ZIP for CATV /MATV installation and service. Comes in attractive sturdy case with a detachable line CIRCLE 39 ON FREE INFORMATION CARD

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cord. Suggested retail price: $119.50. -PTS Electronics, Inc., 5233 S. Highway 37, Box 272, Bloomington, IN 47401. CIRCLE 96 ON FREE INFORMATION CARD Mow FM TUNER PREAMPLIFIER, model 630, is the latest addition to this manufacturer's 600 series components. The 630 features an extremely low-

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high FREQUENCY METER 21 million Americans have blood pressure But 50 percent of those who have it don't know it When blood pressure goes higher high ll sets than rt should, and slays for testing the stage for heart attack or stroke Most cases of high blood pressure can be controlled with drugs and noise, low- distortion preamplifier section, phono other advances in treatment. That's reg. mobile see your doctor performance with noise 80 -dB below a 1 -mV why yea should ularly Only he can tell it you need input reference level (1 -mV sensitivity, IHF -A). help Distortion is virtually immeasurable. A phono transmitters overload figure of 250 -mV plus switch -selectable phone input sensitivity ensure compatibility with a public .lc..,. wide variety of cartridges. The preamp section from your receives A.wcl.11on and N.M also provides precision tone and contour con - turn page Tests Predetermintt r Frequencies Kieps 40 25 to 1000 MHz Kleps 30 Kleps 1 Extended Range Ct +' 950 MHz Band Pin Diode Attenuat r or Full Range Covelaç e as Signal Generrtcr Kleps 10-20 Measures FM Deviation

The FM- 2400CH provides an accurate frequar y Kleps 10 standard for testing and adjustment of motile transmitters and receivers at predetermined frequencies. The FM- 2400CH with its extended range covers 25 to 1000 MHz. The frequencies can be tic-se Kleps 20 of the radio frequency channels of operation Pruf 10 and /or the intermediate frequencies of the re- ceiver between 5 MHz and 40 MHz. Kleps Frequency Stability: ±.0005% from +50 °to Clever Frequency stability with built -in thermorre:er Test probes designed by your needs - Push to seize, push and temperature corrected charts: ± .00025% from to release (all Kleps spring loaded). Kleps 10. Boathook clamp grips wires, lugs, terminals. +25° to +125° (.000125% special 450 MHz crystals Accepts banana plug or bare wire lead. 43/4" long. $1.39 available). Kleps 20. Same, but 7" long. $1.49 Self- contained in small portable case. Complete Kleps 30. Completely flexible. Forked -tongue gripper. Ac- state circuitry. Rechargeable batteries. cepts banana plug or bare lead. 6" long. ;1.79 solid Kleps 40. Completely flexible. 3- segment automatic collet firmly grips wire ends, PC -board terminals, connector pins. FM- 2400CH (meter only) $595.00 Accepts banana plug or plain wire. 61/4" long. $2.59 RF crystals (with temperature correction) 24.10 sa. Kleps 1. Economy Kleps for light line work (not lab quality). RF crystals (less temperature correction) 18.00 sa. Meshing claws. 41/2" long. $ .99 IF crystals catalog prize Pruf 10. Versatile test prod. Solder connection. Molded phenolic. Doubles as scribing tool. "Bunch" pin fits banana jack. Phone tip. 51/2" long. $ .89 All in red or black - specify. (Add 50C postage and handling).

Write for complete catalog of - test probes, plugs, sockets, connec o s,earphones, headsets, miniature components. Available through your local -_ distributor, or write to: RYE INDUSTRIES INC. rve International Crystal Manufacturing Company. Inc. S T R 132 Spencer Place, Mamaroneck, N.Y. 10543 10 North Lee. Oklahoma City. Oklahoma 73102 In Canada: Rye Industries (Canada) Ltd. CIRCLE 27 ON FREE INFORMATION CARD CIRCLE 22 ON FREE INFORMATION CARD 85

www.americanradiohistory.com trots, tape -deck monitor and copy facilities and high- output headphone amplifier. The FM tuner section of the 630 is also a low - noise and distortion device. An elaborate front - SUBBER® end employs a 5- section ganged variable tuning capacitor with components hand -wired directly MARK IV -CUVB onto the chassis for maximum spurious signal rejection. Dual- selectivity IF filter employs a 6- element L -C network with highly linearized phase A TIMESAVING response for low overall FM distortion. The unit also features an FM Dolby switch that provides B- INSTRUMENT type Dolby decoding circuitry and the 25- micro- second de- emphasis required for proper recep- BY CASTLE tion of Dolby encoded broadcasts. The unit is priced at $600. -Nakamichi Research (U.S.A.), Inc., 220 Westbury Ave., Carle Place, NY 11514 CIRCLE 97 FREE UHF -VHF TV tuner and i -f signal analyst ON INFORMATION CARD Incorporates these important features: LUGGAGE -RACK MOUNT ANTENNA, model MR 210, can be clamped securely without drilling Tunes all UHF & VHF Channels holes. Stainless -steel whip has shock spring for Electronic Fine Tuning Dual 40 MHZ IF Output Jacks Battery Condition Indicator MARK IV -CUVB Net $64.95 (BATTERY POWERED ONLY)

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protection. Waterproof mount protects against water damage. Comes with 17 -foot coax cable and radio connector. Suggested list price, $25.95. -The Antenna Specialists, Inc., 12435 Euclid Ave., Cleveland, OH 44106. CIRCLE 98 ON FREE INFORMATION CARD . a.ït!i-. BASE STATION ANTENNA, model 18 -2340, the "Stingray,"is a 16 -foot Fiberglas, omnidirection- TAI al antenna for 23- or 40- channel use. The Stin- tID+I di gray boasts an SWR of 1.3:1 or better, power multiple factor of 2.51 and 4 -dB gain over

MODEL 101 AUDIO TEST SYSTEM consists of two sine/ square /triangle function generators, pulse generator, fre- quency counter and AC voltmeter. As a system it will gen- erate a frequency response plot on an X -Y recorder or scope. FROM KIT TO CAR Time base generator offers symmetrical or independent IN 80 MINUTES! control of the positive and negative sides of the ramp Electronic ignition is "in." Update your car providing a duty cycle of 1% to 99 %. Frequency range with the TOPS in power, efficiency and re- is .002 Hz to 100k Hz. Amplitude is 16 Vpp into 500 Ohms liability - the TIGER SST capacitive dis- with i 5 VDC offset. The time base output drives the X axis charge ignition (CD). of an X-Y recorder. Manual mode provided for setup. The TIGER delivers everything other CO's Audio sweep generator provides manual frequency adjust- promise and more: quicker starting, more - ment or log /linear sweep of 20 Hz to 20k Hz. Blanking gas mileage, -ups elim- power, more tune mode provides zero reference line X -Y recorder reduced on an or inated, lifetime plugs and points, tone burst. Amplitude is 16 Vpp into 500 Ohms or 10 Vpp repairs and pollution. into 8 Ohms. The TIGER can be built and installed in your car in 80 minutes. The TIGER is Pulse generator frequency range is .002 Hz to 800k Hz. unique/ Pulse width is adjusted independent of frequency from 4 The TIGER comes with a switch for TIGER seconds to 40 nanoseconds. Outputs are complementary or standard ignition for 12V negative ground TTL. only. AC Voltmeter has full scale sensitivities from 1 mV to 250 Simpli -Kit $21.95 V. Fast /slow, peak/true RMS and log /linear modes are pro- POST PAID U.S.A. vided. Output drives Y axis of X -Y recorder. WE ACCEPT: Mastercharge or BankAmericard. Frequency counter is 6 digit, line triggered, and reads isotropic for professional quality performance. Its Send check or money order with order to: either internal or external. Sensitivity is 100 MV peak at Fiberglas construction makes the Stingray wea- 20k Hz. 1 /V2 sec. update. 50 /60 Hz. therproof and lightweight (9 pounds). The instal- lation of this two -piece antenna is simple. All Dimensions: 8x14x3. Shipping weight: 9 lbs. Star Corporation mounting hardware is supplied as well as 3 -foot $650. Stock to 30 days. Warranty: 1 year, 3 -year $60. DEPT. FF, P.O. Box 1727 length of cable and attached connector. -GC Grand Junction, Colorado 81501 1894 Commercenter W. .105 Electronics, 400 South Wyman, Rockford, IL FIDELITY SOUND San Bernardino, Ca 92408 17141 8897623 61101 CIRCLE 99 ON FREE INFORMATION CARD CIRCLE 5 ON FREE INFORMATION CARD CIRCLE 6 ON FREE INFORMATION CARD

www.americanradiohistory.com from Polaris new books CADDY -PROBE 40 KV DUAL RANGE r -,. .- POL ARls Measures VOLTAGE And CURRENT HOW TO BUY & USE MINICOMPUTERS & MICROCOMPUTERS, by William Barden, Jr. Howard W. Sams & Co., Inc., 4300 W. 62 St., Indianap- olis, IN 46268. 240 pp. Softcover $9.95. RANGE This book demonstrates the ABC's of the ever -growing field of microcom- DC puter and minicomputer technology. Written in easy -to- understand lan- 1: 40,000 VOLTS guage, it gives the beginning enthusiast a basic understanding of what a 0 -400 MA DC computer is, how it operates and how he can own and use a functioning home system for recreation or work. The introductory chapters deal with microcomputer basics, with the emphasis on "real- world" applications. Short programs illustrate computer 34.95 programming in BASIC and other rudimentary machine languages. One chapter gives several program examples, including a complete BASIC game program. Other chapters discuss peripheral devices, with interface exam- Fits Your Caddy ples; program goals and techniques; and describe some available micro- computers and minicomputers. A handy index in the back of the book contains much useful reference material.

EASI -GUIDE TO HOME ELECTRICAL REPAIRS, by Forest H. Belt. Howard UNIVERSAL TEST RIG W. Sams & Co., Inc., 4300 W. 62 St., Indianapolis, IN 46268. 144 pp. Soft - cover $3.50 (in Canada, $4.40). This handy step -by -step guide takes the mystery out of the simple home electrical repairs a lot of people shy away from. Plenty of factual information, explicit instructions and relevant illustrations are provided. The book emphasizes working safety and outlines in simple, straightfor- ward language how to work with electrical materials; It even tells you what to do in case of emergency. Other chapters deal with such topics as twisting, soldering and taping free joints; making connections; and crimping lugs, etc. Instructions for repairing many different appliances are accompanied by simple clear photographs.

$229.95 PJS-298 C.R.T. Included 33KV Leaded Glass CRT 40KV Meter Build-In Speaker Obsolete -Proof The PJS -298 Universal Test Rig for tube and Solid Ssa e TVs designed for servicing high voltage chassis. Built -in s)eaker for convenient audio checking, 40KV -50Ua sensitivity Teter constant monitoring of the anode voltage. Up- dating its a :amp - lished by means of plug -in modules. (Extension cables incl. idedl.

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Full One Year Battery Life VHF /UHF Subber I.F. - Video Trouble Shorter e Convergence Generator s Dots and Cross -Hatch Fat:erns The "SG -785" is a multi- functional i.nstrumcn for fast, efficient trouble- shooting and adjustment: of all Color and B &W tvs. It is ideal for both shop and field D A n A work. (Cables included.) Dana Laboratories, Inc. /ele/jjaiic 2401 Campus Dr, Irvine, Ca 92715, (714) 833 -1234 108 -02 OTIS AVENUE, CORONA, N.Y. 11368 CIRCLE 61 ON FREE INFORMATION CARD =no= CIRCLE 28 ON FREE INFORMATION CARD

www.americanradiohistory.com ANNUAL INDEX new lit JANUARY -DECEMBER 1977 NEW EKO 700 To present the maximum number FREQUENCY of articles to our readers, we have COUNTER KIT not published the Annual Index as part of this issue. A 4 -page bro- More information on new lit is chure containing this index is avail- available from the manufacturers able for those who need one. To get of items identified by a Reader At last! A digital counter every your free copy, send a stamped CB'er /Hobbyist can afford. Exclu- self- addressed envelope (legal size) Service number. Use the Free In- sive transmitter -Keyed "sniffer" to: formation Card following page circuit activates counter only on transmit, giving accurate readout of 98. channel frequency. Standard coax connectors and mounting brackets Radio -Electronics CB RADIO COMPONENT REPLACEMENT make mobile installation a snap. IC Annual Index GUIDE, K- 1200A, provides service technicians Digital circuitry. Freq. range: 5 Hz- with 48 pages of information on capacitors, semi- 27 MHz (all 40 CB channels) Ac- 45 East 17th Street conductors, resistors, radio interference filters curacy: ±1 PPM ±1 Digit. Read- New York, NY 10003 and installation aids. A four -page section on 536 out: Five 0.5" LED Displays; 10 standard capacitors gives their capacitance val- MHz crystal oscillator KHz /MHz ues, voltage ratings and capacitance tolerances. Timebase switch; Compact design: Catalog also contains a 26 -page semiconductor 23/8 "H x 61/8"W 55/6 "D. Assembled Any requests postmarked on or cross -reference for CB replacement parts and $99.95 before February 28 are free. After four pages of IC basing diagrams.- Sprague Products Co., 509 Marshall St., North Adams, that date there is a FREE '78 EICO CATALOG 25c fee. Ques- MA 01247. tions and Check reader service card or send 75¢ comments about any- CIRCLE 104 ON FREE INFORMATION CARD for first class mail. See your local EICO thing other than the Index that are Dealer or call (212) 272 -1134, 9:00 included with your request a.m. -5:00 p.m. EST. Major credit cards cannot REPLACEMENT GUIDE for CB coils is a handy accepted. be handled. Send them separately 12 -page listing and cross -reference guide for EICO -283 Malta SL, z7E/CO to our Editorial Offices. some 3,300 manufacturers' part numbers. The Brooklyn, N.Y. 11207 more than 67 CB trade names included in the J listing are cross -referenced to corresponding CIRCLE 51 ON FREE INFORMATION CARD Miller part numbers. -Bell Industries, J.W. Miller Div., 19070 Reyes Ave., Box 5825, Compton, CA 90224. 2 Great New Experimenter's Project Books! CIRCLE 105 ON FREE INFORMATION CARD BUILD -IT BOOK of DIGITAL ELECTRONIC upplunm TIMEPIECES THE COMPLETE BUGWORKS, Catalog No. 803- A data -packed guide to building BUGS TAKE 0156, provides designers, researchers, hobbyists '" modern timekeeping devices- and students with 24 pages of circuit design and

. rugged shipboard clocks. BIG BITE OFF educational aids. More than 155 products are second -splitting digital IC described along with specifications, prices and chronometers, decorator digital PRICE. ordering information. Some of the wares dis- 4 clocks, a precision timer, a played include solderless sockets, breadboards frequency /period meter, a tide and accessories for "plug -in" wiring as well as and moon clock, automatic the functional modules known as "outboards." alarm setter, etc.- including The latter are available assembled or in kit form. full -size PC board layouts. Full of projects that A list of hardware is supplemented by educa- bring you lab- quality time measurement-a tional books and reference works, including Bug - clock with strobe, scan, and numerous signal books, combined texts and lab manuals. -E &L output capabilities; control accessories: a $16.50. (Save $2.50) Instruments, Inc., 61 First St., Derby, CT 06418. flashing -light alarm for the hard -of- hearing: a Bony, Larsen and Titus' CIRCLE 106 ON FREE INFORMATION CARD primary standard of frequency: date, time, & in- 8080 Microprocessor home study course.

terval capability for your microcomputer; giant When the Bugs bite it saves you bucks. Learn the HEATHKIT CATALOG No. 817 describes close to displays: multi -city clocks, etc. 295 p., 209 ill. complete operation of the 8080 Microprocessor 400 different electronic kits, as well as many for lust $16.50 (A good Paper $6.95; Hardbound Order No. 905 special offer only until Heath -recommended assembled units. The kits $9.95 March 1. 1978.) Bugbooks V 8 VI consist of 900 DISPLAY ELECTRONICS pages of clearly written text that take you from basic include a complete line of personal computers, an Contains over 70 projects using digital electronics to interfacing and programming. audio -signal processor for hi -fi systems, a digital Even better. the Bugs will foot the full $16.50 if arrays and displays, light - electronic scale for home use and new test equip- EáEGtlyotdCS you buy one of our new MMD -1 microprocessors emitting diodes, infrared - within 90 days. Your dealer will deduct that from ment. The Heath -recommended assemblies fea- emitting diodes, photodiodes, your purchase price ture a microcomputer -based chess game, video- liquid crystals, phototran- So get your Bug Books now Enclose $16.50 for cassette recorder, phone answerer /recorder and both books. sistors, light- activated SCRs, an electronic greenhouse. -Heath Company, fiber optics, electrolumines- NAME Dept. 350 -420, Benton Harbor, MI 49022. cence. etc...with detailed in- ADDRESS CIRCLE 50 ON FREE INFORMATION CARD structions on how to build 2- CITY color displays, LED transmitters, receivers, SECURITY SYSTEM CATALOG No. A -78 fea- STATE digital counters, electroluminescent panels, ZIP tures 72 pages of professional -grade alarm sys- AC/DC indicators, photodetectors, oscillators, ems tems, ranging from simple door -switch installa- modulators, voltage -level indicators, IC tester. tions to sophisticated infrared and ultrasonic light- a detectors. Some of the devices listed are: fire and controlled switch, character generator, E &L INSTRUMENTS, INC. an LED VU meter, flashers, burglar alarms, a 61 First Street. Derby, Conn 06418 burglar detectors, remote control systems, sig- 735 Xenon strobe light, a microcomputer with (203) -8774 Telex No 963536 naling devices, silent phone connections, tele- binary and octal readouts, and several Enclose check money order or numoers Iron phone dialers, locks, tools, books, etc. Diagrams BankAmencard or Maslen Charge we win and illustrations allow technicians to make preci- sophisticated games. 252 p., 195 ill. snip posi paid anywhere in continental u S Paper $5.95; Hardbound $8.95 Order No. 861 sion connections, wherever necessary. -Moun- tain West Alarm Supply Co., 4215 N. 16 St., Box SEND NO MONEY! Wean invo,ce on 10 -DAY FREE TRIAL. you 10780, Phoenix, AZ 85064. cl STAB BOOKS BLUE RIDGESUMMIT, PA. 17214 CIRCLE 107 ON FREE INFORMATION CARD CIRCLE 101 ON FREE INFORMATION CARD 88 CIRCLE 12 ON FREE INFORMATION CARD

www.americanradiohistory.com burglar -fire alarm catalog 'FREE! next o MORE THAN 900 PRODUCTS month 0 o detectors, controls, sounders, JANUARY 1978 locks, tools Digital Frequency EVERYTHING NEEDED Display For Hi -Fi 100% Solid State Includes 10:1 Probe TO PROTECT HOME, Spruce up your hi -fi with More Professional scope : -rfor- BUSINESS; INSTITUTION mance for your money! DC D 10 this add -on for your MHz bandwidth, AC and DC :oup- Huge high quality professional selection of ling, 11 position calibrated :tten- fact -filled pages with alarm oroducts. 64 tuner. Complete con- uator, 10 mV /cm sensitivitt, push- detailed specs, diagrams, technical notes. struction details for a dig- button operation. Outs7artding Products range from basic switches, con- features: Built -in TV Sync Separa- trols, bells, sirens to most sophisticated ital display of the frequen- tor; Digitally controlled trigger cir- 1 detectors radar, modulated or passive cy your tuner is tuned to. cuits; reference baseline di >play; infrared, microwave, ultrasonics, ion, data calibrated 21 step sweep soeed; links using pulse code multiplex, FSK Fully regulated power supply; Cus- radio, automatic phone dialers, leased line tom Bezel for standard camera panels. Full sel- Programmable connections and display mounting. Assembled $425 OC ection of tools, relays, wire, foil, terminals, TV Games books. WRITE FOR FREE CATALOG TODAY! from FREE '78 EICO CATALOG A look at the entries Check reader service card or ;erod 75¢ (Outside U.S.. send $1 00.) major manufacturers for first class mail. See your o:a EICO the Dealer or call (212) 272 -- 134. 9:00 into the area of micropro- a.m. -5:00 p.m. EST. Major cedil cards west alarm accepted. mountain -based TV games. box 10780phoenix, az 85064 cessor EICO -283 Malta St., T76SW Brooklyn, N.Y. 11207 1.Lid (602) 263 -8831 One manufacturer plans +/ CIRCLE 12 ON FREE INFORMATION CARD on introducing accesso- 'CIRCLE 51 ON FREE INFORMATION! CARD convert his TV ries to Put Professional Knowledfle and a Try this exciting game into a home micro- DEG REE Build computer. COLLEGE new hobby! in your Electronics Career ti rough your own electronic concert organ. It's easy. No technical Pink Noise Generator knowledge required. Just Easy to build device has a follow the clearly pictured multitude of applications, instructions of the famous in hi -fi testing Wersi do- it- yourself system. especially ChDose from seven different and evaluation. models. Send $2.00 (refundable) with coupon for SPECIAL SECTION Earn Your colDrful 104 page catalog. Bench Tools and Handy Gadgets DEGREE 11) WERE! by correspondence, while contin ling your A look at what's available present job. No commuting to cls,ss. Study for the at your own pace. Learn from complete and to make life easier explicit lesson materials, with additional hobbyiest, experimenter assistance from our home -study irstructors. and servicer. Advance as fast as you wish, but take all the time you need to master each opic. Profit from, and enjoy, the advantages of directed PLUS but self-paced home study. The Grantham electronics degree pro- Novel CB Circuits gram begins with basics, lead4 f rst to the to :hc B.S.E.E. Wersi Electronics, Inc. A.S.E.T. degree, and then Dept. 24, Box 5318 Evaluating Phono degree. Our free bulletin gees complete 1720 Hempstead Road Cartridges details of the program itself, the degrees Lancaster, PA 17601 awarded, the requirements for each degree, and how to enroll. Write for I`'uPetin R -77. Enclosed is $2.00 for my copy of your 104 page catalog. Hi -Fi Lab Test Reports Grantham College of E'i ineering Name Z -80 Computer Corner 2000 Stoner Avenue Address P. 0. Box 25992 City __ State p and much more Los Angeles, CA 90025 I- J Worldwide Career Training thru (Arne Study CIRCLE 40 ON FREE INFORMATION CARD 89 CIRCLE 45 ON FREE INFORMA' fCN CARD www.americanradiohistory.com WIREWRAP . Wire Wrap Kits LW Si 1.00 82 160 Cut & Stripped 530 Kynar Wire 86 5+ In Red, yellow, Blue, White, Black 90 9 800 55' 94 321 5 02 Green or Orange. All lengths overall. 1" strip on each end. 98 341 6 34 1.02 3 63 6 1- 7114 Kn N o.1 $6-95 Kn No 19.95 In 4 54 150 ].50

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41 53

1 30 05 84 CLASSIFIED COMMERCIAL RATE (for firms or individuals offering commercial products or ER services). $1.40 per word (no charge for zip code) ... minimum 15 words. NONCOMMERCIAL RATE (for individuals who want to buy or sell personal items) 85C per word . . . no minimum. ONLY FIRST WORD AND NAME set in bold caps. Additional bold face (not available as all caps) at 1010 per word. Payment must accompany all ads except those placed by accredited advertising agencies. 5% discount for 6 issues, 10% for 12 issues within one year, if paid in advance. All copy HOBBY WRAP subject to publisher's approval. Advertisements using P.O. Box address will not be accepted until TOOL advertiser supplies publisher with permanent address and phone number. Copy to be in our hands $34.95 on the 26th of the third month preceding the date of the issue (i.e., August issue closes May 26). FREE When normal closing date falls on Saturday, Sunday or a holiday, issue closes on preceding working day.

Wire Wrap Boards TUBES, receiving and Industrial, semiconduc- 96c. yM'Cm...eno. BUSINESS OPPORTUNITIES tors, factory boxed, low prices, free price list. TRANSLETERONIC INC., 1365 39th Street, 1563 .33.3 33 BIG money in CB repair! Amazing illustrated - Brooklyn, NY 11218 212- manual shows how with no electronic knowl- 633-2800 edge and simple equipment. Send $9.95 or 12131 797 4002 or 797 4007 BankAmericard / Mastercharge number, exp. date. C.B. CITY -R, 600 E. Franklin, Monterey, Page Digital Electronics CA 93940 FREE KIT Catalog STOP! Take a minute & let as send contains 1701 East Orange Grove Blvd our latest kit catalog. If you like, TEST CABLE FM station. No investment, good spare A Pasadena, California 91104 send us the name S address of a EXPERI - time income, others operate for you. Details free. who may be interested Orders under 525 and COD Orders add 52 friend also MENTE R'S All others shinned UPS Ppd. CAFM, Box 5516 -FL, Walnut Creek, CA 94596 and we'll include to you our booklet EQUIP. We accept 5,sa and Mastercharge "How to build- electronic thermometer" CIRCLE 10 ON FREE INFORMATION CARD SCIENTIFIC INSTRUMENTS HIGHLY DAGE BOX I054R LIVERMORE CA 94550 PROFITABLE ONE -MAN SPEAKERS-Save 60%. Factory assembled or ELECTRONIC FACTORY kits. Free catalog. QUALITY ACOUSTICS, 15428 Investment unnecessary, knowledge not re- Center, Harvey, IL 60426 quired, sales handled by professionals. Ideal home business. Write today for facts! Postcard will do. Barta -AO, Box 248, EDUCATION & INSTRUCTION GREAT Walnut Creek, CA 94597. GRANTHAM's FCC License Study Guide -377 IDEAS FROM pages, 1465 questions with answers /discus- WEST SIDE ELECTRONICS sions -covering third, second, first radiotele- PLANS & KITS phone examinations. $13.45 postpaid. GSE PUB- LICATIONS, 2000 Stoner, Los Angeles, CA 12/24 HR. MT1 BI- LINEAR amplifier, amateur band 2 -30 MHz, 90025 50/60 Hz 60 -150 watt. Frequency counter 30/300 MHz, miniportable /mobile, memory. Base antenna, TELEPHONE bugged? Don't be Watergated! AC /BATTERY circular polarization omnidirectional, 6, 2 CB, Countermeasures brochure $1.00. NEGEYE

- t > . meters. Construction plans $3.00 each, all 24 HR. ALARM t ri fl three LABORATORIES, Box 547 -RE, Pennsboro, WV I ir. t -t $7.50. Kits available. PANAXIS PRODUCTIONS, 26415 XTAL TIM EBASE Box 5516 -FL, Walnut Creek, CA 94596 10 MIN. SNOOZE SMART CALENDAR NEGATIVE -Ion generator. Plans- $10.00. F.C.C. EXAM MANUAL The MT1 is the Ultimate Digital Timepiece. 17 Kit -$165.00. (Details -$1.00.) GOLDEN ENTER- PASS FCC EXAMSI Memorire, study- Tests- digits continously reads out the month, date, time, PRISES, Box 1282 -RE, Glendale, AZ 85311 e tS-A4fw FCC Ist and Ind dass Radio- MT1 Answers for ers alarm setting, and timer. The operates on 110 telephone licenses. Newly revised multiple fCe Tor VAC, with battery backup in case of power failure; SAVE 50%. Build your own speaker system. Write choice questions and diagrams carer all '4'nd tag areas tested in FCC exams, plus Self-Study Comm or off 12 VDC for operation in an automobile or McGEE RADIO ELECTRONIC, 1901 McGee C1°Ds boat. Street, Kansas Ability Test. $9.95 postpaid. Money - City, MO 64108 back guarantee. The timer on the MT1 can be used in one of three modes to control an external device. COMMAND PRODUCTIONS P.0. 809 26348 E RADIO ENGINEERING.DIV SAN FRANCISCO, (AL. 94126 The MT1 is designed for custom installation. Several partial or full display can be run from one master clock unit. MT1- kit less case $109.00 FOR SALE

PINK NOISE RECONDITIONED test equipment. $0.50 for cat- GENERATOR KIT. alog. WALTER'S TEST EQUIPMENT, 2697 Nick- tn Inexpensive unit allows el, San Pablo, CA 94806 U proper set -up of graphic z equalizer in a stereo system. O Easy use. PNG -C PICTURE TUBE MACHINE cc to We buy and sell NEW and USED CRT H PNG -K - Complete Kit $13.95 Only $9.95 rebuilding machinery. COMPLETE U PNG TRAINING. Buy with CONFIDENCE from w -W - Assembled & Tested $19.95 the ORIGINAL MFGR. J AORECCo For complete details send name, address, w WEST SIDE ELECTRONICS ZIP to: P.O. Box 636, Chatsworth, CA 91311 LAKESIDE INDUSTRIES o -41? .11Arrt141-(Yvvfter;(Pc 3520 W. Fullerton Ave. E We pay all in U.S.A. Chicago, Ill. 60647 shipping Continental Phone: 312342.3399 Others add 10 %, California residents add 6% tax. CIRCLE 60 ON FREE INFORMATION CARD 90

www.americanradiohistory.com TIRED OF RECEIVING "SURPRISE PACKAGES" IN THE MAIL? TRY OVER- THE -COUNTER SALES LAT BELOW MAIL ORDER PRICES! PRIME I.C. PLASTIC SIGNAL RE) SOCKETS TRANSISTORS Li IC 's ALL MARKED 8 PIN 10/$1.19 100/$595 MINI 14 PIN 10/$1.39 ] I0/79c 16 PIN 10/$1.49 24 PIN 51$1.49 JUMEO VOLTAGE 40 PIN 4/$1.49 1Ú/99c REGULATORS TO 220 FOR 14, 16 & 40 PIN HIGH 6 V. at 1 AMP THAN A LESS 2/99c EFFII',I : NCY PENNY A PIN (1$19.4

N -FET's PHOTO PHOTO SOLAR CELLS 1500V. SIGNAL TRANSISTORS 2N718 10/99c 2N4303... TRANSISTORS DARLINGTONS 2x2cm at 130mA 1 AMP 2N2369A (500mc) 3/99c GEN. FIRF 4/99c SIMILAR TO FPT 100 MOTOROLA $1.49 ea. RECTIFIERS 2N2484 10/99c BF255: 2N4274 (400mc) 4/99c 4/99c 4/99c 104950 10/$199 500m 2/99c

INFRA RED RF POWER POWER TRANSISTORS TTL PULSE BUILD YOUR OWN SUR IN TATURE PAPER TAPE H. Y DIODE DETECTOR DEVICES 2N301 M1E3055 TRANSFORMER T0 3 GERMANIUM NPN PLASTIC ULTRA LOW LEVEL READER 20 Nk a 100mA 1.25W at 175mc $1.95 2/99c 2/$1494 /99c $295 $395J 1 /10" CENTERS STACKABLE... - 1.50w at 470mc 555 741 LM3900 'IFF -1 PHOTO $2.95 PHOTO (CA 3401) TUNIIBG DIODE DETECTOR TIMER OP AMP TRANSISTORS Cj ta. 30 pf ULTRA HIGH SPEED 1.00W at 2000mc 29c 12c 49c Q 20 i : 47mc

NS $395 I $12.95 10/$950 RISE TIME 1 2 /19c Ilik.COME INTO ANY ONE OF OUR LOCATIONS 1

LOS ANGELES PORTLAND SEATTLE DENVER (213) 9674611 (503) 646 -4044 (206) 575 -3709 (303) 573 F.214 LMN ELECTRONICS WIZARD of PARTS SEMION of SEATTLE ELECTRONIC ! OLLIPOP

1042 E. GARVEY AV., W. COVINA, CA. 8225 SW CIRRUS DR., BEAVERTON, ORE. 964 INDUSTRY DR.. TUKWILA. WA. 5643 N. BROADWAY, 7E'VER, CO.

(VINCENT & SAN BERDO FWY.) (KOLL BUS. CNTR /WASHINGTON SQUARE) (KOLL BUS. CNTR. /SOUTH CENTER) (I -25 & 58th A .)

IF AT ALL POSSIBLE TRY TO DROP IN f0 ONE OF OUR LOCATIONS BUT IF YOU LIVE TOO FAR AWAY YOU MAY ORDER BY MAIL FROM. $20 MINIMUM CALIF. RESIDENTS ADD 6% NO BACK ORDERS F. Reichert Sales YOUR PARTS OR REFUND WE PAY ALL POSTAGE & HANDLING 1110 E. GARVE`' AVE. FOR UNDER 8 HOURS PROCESSING SEND MONEY ORDER, CERTIFIED OR CASHIERS CHECK. W. COVINA, C. 91790

`SORRY! WE CANNOT ACCEPT COD'S, PHONE ORDERS, FOREIGN ORDERS, OR CREDIT CARDS. PRICES GOOD UNTIL JANUo1R' 3, 1978j

CIRCLE 71 ON FREE INFORMATION CARD

www.americanradiohistory.com GOLDMINE of parts, powerful power supply, COLOR video tape recorders $250.00, TV cam- documentation, in complete Cartrivision elec- AMAZING ELECTRONIC PROJECTS and PRODUCTS: era $150.00, videotapes $4.00, Cartrivision man- tronic assembly. Perfect for microprocessor and Lasers Super Powered, Burning, Cutting, Rifle, Pis- uals, parts and accessories. D.M. TRIMBLE, 5835 all electronic applications. $24.95 total. Master tol, Pocket. See in Dark -Shotgun Directional Herma, San Jose, CA 95123 Charge, BankAmericard. Free brochure. MADI- Mike- Unscramblers -Giant Tesla- Stunwand- SON ELECTRONICS, INCORPORATED, TV Disrupter- Energy Producing, Surveillance, De- 369, DIGITAL IC's, TTL, CMOS, plans, kits Madison, AL 35758. Satisfaction guaranteed. tection, Electrifying, Ultrasonic, CB, Auto and and parts. Mech. Devices, Hundreds More -All New Plus Free bargain flyer. T. WONG, 103 E. Broadway, INFO UNLTD PARTS SERVICE. Catalog $1. Informa- Dept. 4A, New York, NY 10002 MICROCOMPUTER systems troubleshooting tion Unlimited, Box 626, Lord Jeffery Court, Am- manual. Digital gate decode chart. $5.00. herst, N.H. 03031. Both ELECTRONIC parts! Catalog, mailing list. Send MICRO -INFO ASSOC., Box 849, Castroville, CA $1 to: B.C. ELECTRONICS, P. O. Box 226, West 95012. Cal. res. add 6% tax. HISTORICAL radio electronics directory; Ser- Lynn, MA 01905 vices- parts, tubes, collectors, covers A -Z, TRS-80 users group -join now -monthly news- $9.95 color, $5.00 standard. HRS, Box 15370 -E, FREE catalog. IC's, Semi's. CORONET ELEC- letter- $17.00 first year. MARSH, 621 13th S, Long Beach, CA 90815 TRONICS, 649A Notre Dame W., Montreal, Que., Onalaska, WI 54650 Canada, H3C -1H8. US Inquiries. TEN pounds fantastic variety capacitors, resis- ULTRAVIOLET EPROM eraser. Handles all tors, IC's, transistors, more: $10. Fifteen West- WIRE and cable. New expanded list free. RAM EPROM types. $98.00. Free data sheet. KING- ern Electric relays, 2' rack: $9.75. Postpaid. ELECTRONICS, Box 336 -R, Brookhaven, NY STON LABORATORIES, Box 894 -R, Melbourne, Satisfaction guaranteed! COMPUTRON, Box 11719 FL 32901. (305) 723 -2200. 18160 -E, Cleveland, OH 44118 FREE catalog. Solar cells, NICad's, kits, calcula- VIDEO cassette tape recorders RCA Selectavi- DIAGRAM manuals, buying and selling Rider, tors, digital watch modules, ultrasonics, strobes, sion. Free information. HODAPP TV SALES, 322 Sams, Supreme, factory material. BEITMAN, LED's, transistors, IC's, unique components. Main St., St. Clair, MN 56080 1760 Balsam, Highland Park, IL 60035 CHANEY'S, Box 27038, Denver, CO 80227

NAME brand digital /analog test equipment. Dis- YES,YOU CAN count prices. Free catalog. SALEN ELECTRON- ICS, P.O. Box 82, IL 60076 SURPLUS UILD Skokie, Govt. AN WIRE wrap wire #30 Kynar, white, 100' $2.00; ELECTRONIC ELECTRONIC 500' $8.00; 1000' $15.00. Ppd. Send 256 for picture flyer. U.S. only. STAR -TRONICS, Box ORGAN 683, McMinnville, OR 97128 EQUIPMENT Thathasa PIPE ORGAN SOUND With DEVTRONIX easy to build assemblies. DON'T purchase alarm equipment before getting CATALOG Own the ultimata in organ design 8 sound our free catalog. SASCO, 5619 -A St. John, Kan- at Y, the cost of commercial organs. sas City, MO 64123 New ITEMS ... New BARGAINS! Several models to choose from. UPON REQUEST! BROCHURE AND DEMO RECORD $1.00 FREE If you haven't received our new SOLITREX electronic voltage regulators for car Catalog, write for free copy today. Address: Dept. RE Dept. B alternators. Universal replacement for all. Full 5872 Amapola Dr. warranty for 5 years. Send $19.95 to: SOLID : ORGANS, INC. San Jose, CA 95129 STATE DEVELOPMENT CO., P. O. Box 108, FAIR RADIO SALES 1016 E. EUREKA Box 1105 LIMA, OHIO Clarkson, Mississauga, Ont., Canada, LSJ 3X9 45802

COMPUTER VIDEO MONITOR CHRISTMAS SPECIAL 12" B &W video monitor,made by ELSTON. These are in warranty returns, which have LSI KIT Reg. $77.77 been completey checked out and are DMM ßv1 guaranteed to be in perfect working condition. We provide 14 page service maual & circuit diagram. Original cost , t, ' . ,h over $250.00 in lots of 100. SPECS: Signal input, Composite lk) I _v video & sync. per RS -170. lto 2 volts p -p, sync polarity neg. Separate Vert& f E r.Horiz. sync. 1 to 5 volts pos., can be concord eoc changed to neg. Impedance 150K ohms 75 ohm termination. Video response,within 3 dB from 15 Hz to 15 Mhz. Resolution 750 lines center, I 0 -I I 1, I ` 650 corners. Lineari}y,1%. Picture scan,15750 horiz. lines /sec. Vert. 47 to 63 pulses /sec. Retrace time, 11 usec max. STOCK NO.5525R, tested & working with data. $89.50 WIRE WRAP PROTOTYPE BOARDS AUTO RANGING AUTO POLARITY 11T 7 "4 1{ 1Fi-A1 AUTO ZERO 3 LARGE DIGITS (1/2 ") ) 1 $ 5 tdï8ñ :: 1 e i : #t I qt 1k lr 11 t14t ü RECHARGABLE

I 1 1 :1'11111 MEASUREMENT RANGES: Voltage (AC -DC) 1MV -100V, Cur- r ?{ 11 .11 ! . ì1 ri rent (AC -DC) 10NA -1A; RESISTANCE: 112- 10M52. Basic DC Prices on wire wrap boards have been up to -- accuracy, better than 0.1% 1 digit. POVVER : 4 AA batteries about $275.00 for the large boards. We have 3 boards, 2 out of equipment, and one brand new. The first 2 have Irechargable batteries optional). the original wire on them, which must be removed. NI -CAD BATTERIES: $6 AC CHARGER: $4.95 STOCK 6558R 78 to 100 14 & 16 pin sockets $18.75 2/35.00 ENCLOSURE: $12.95 TEST LEADS: $2.95 STOCK 6559R 40 to 50 14 & 16 pin sockets $11.75 2/22.00 SHUNT KIT FOR 3 CURRENT RANGES: $4.75 STOCK 6592R, 40 16 pin sockets & 4 LSI 24 pin sockets, gold plated. all wire wrap pins brought out to top $24.50 2/45.00 ORDERING INFORMATION All boards have Vcc and Ground planes. SHIPPING & HANDLING: $3.00 + .50 cents insurance Visit our retail outlets:DELTA ELECTRONIC HOBBIES, 5151 Buford Hwy. Doraville (Atlanta) Ga. & DELTA ELECTRONICS California residents add 6% sales tax. WAREHOUSE OUTLET 590 Commonwealth Ave. Boston, Mass. N ELECTRONICS WAREHOUSE Inc. DELTA ELECTRONICS a 1603 Aviation Blvd., Redondo Beach, CA 90278 7 Oakland St. P.O. Box 2 Include sufficient TELEPHONE: 12131 376 -8005 Amesbury, Mass. 01913 BakhtMEPI :APP fudetl9 Write fore droie It. Write for Free Catalog. You are invited to visit our store above. (617) 388 -4705 new catalog 18. " CIRCLE 25 ON FREE INFORMATION CARD CIRCLE.. 14 ON FREE INFORMATION CARD www.americanradiohistory.com Your Home $9.95 Hobby Center for Quality Kits MA1003 MOBILE CLOCK Complete Clock Kit and Projects MODULE (National) 0 B B I complete 4 DIGIT 12/24 HOUR $1895 Includes: PC Board. 5316 Clock Chip, all components 6 Power Supply 83 - min. 6 sewn Attaches directly to Automatic Nightt me Features: Displays hrs 6 min. Switch to I (201)964.5206 AM /PM Indicator Elapsed Timer 0 V S E 9 -12V Battery Dimming Fluorescent Display gives color choice Fluorescent Display gives Color Choice (Red. Blue. Green, or Amber) - specify (Red, Blue, Green or Yellow) SEND FOR FREE HOBBI HOUSE CATALOG when used with corresponding Color Filter w /corresponding Color Filter LOWEST PRICES ON PRIME COMPONENTS when used Includes - 'Module, Switches. Filter & Specs OPTIONS: If alarm Function desired odd $2.50 Some Examples (includes speaker & all components) . _. Plexiglas Case Kit - Red or Blue $2.00 SEMICONDUCTORS PAIR OF 6" PIONEER Any 10 for $1.00 Monthly Specials 1N456 5,1V 1 Watt Zener PINCUSHION SPEAKERS 1N459 5 6V 1 Watt Zener 60 Hz. Crystal Time Base Kit Two for 17.95 ohms, 7 watts $3.95 pair 32 x 1N645 10V 1 Watt Zener Use with Digital Clocks for 12VDC or Portable Operatic

1N1084 15V 1 Watt Zener Pair of 4" Full Range Speakers KIT INCLUDES: PC Divider Chip 1N4384 20V 1 Watt Zener 40 ohms $2 95 pair Board, 5369 3.9V 400 MW Zener 22V 1 Watt Zener 3.5795 MHZ XTAL and all other parts

6.8V 400 MW Zener 31V 1 Watt Zener Complete Instructions 8.2V 400 MW Zener BRANDED, FACTORY PRIME -555 Timers Any 6 for $1.00 VOLTAGE REGULATORS 3/$100 2N722 2N2368 2N2907 Positive -To 220 Pkg Negative -To 220 Pkg. 2N914 2N2369 2N3300 7905 5125 2N918 2N2484 2N3250Á 7805 $100 100 7912 125 WOOD CLOCK 2N1893 2N2904 2N3702 7806 1 1 00 7915 25 2N2219 2N2906A 2N4033 7812 CABINETS 7815 100 To-3 Pkg. 200 Volt 3 Amp Bridge 3 /61.00 7824 100 LM309K 1.25 Includes: Filter & Back Any 2 for $1.00 Walnut Grain or 3N140 (Silicon Field Effect Transistor), 2N4949, 2N2102 7 SEG LED DISPLAYS Black Leatherette Finish 33" Type 707 /MANA 14 Pin Dip $5.00 ea. HIGH POWER TRANSISTORS Common Annode or Cathode 10 for $5.00 Dimensions (Inside) Prime S59ea Factory -A - 1- 13/16 "H, 5'2"W, 4 -4"D 2N 3055 NPN (ITT-T0 -3 Case) 2/$1 00 CLOCK CHIPS TRANSFORMERS - 1'á'H, 4i "W, 4 DIS 410 NPN (TO -3 Case), Extra Filters Red, Smoke MM5314 $3 50 Plug type -12VAC 250MA 2.50 Amber. & Green $ 60 Equiv. to ECG 162 2/$1.00 PC Blue, - MM5316 3 50 Mnt.12VAC 250MA 1.50 MM5387 (Hi Cur 5316) 3.95 Bkt Mnt SVAC 6 Amp 4 95 MM5375 3 95 IN 4148 SWITCHING DIODES Dual Range DVM /Multimeter Kit Factory Prime. Taped & Reeled 50/51 00 BRIDGES IC SOCKETS DVM Kit only $2V-5 s_mplete

11 Amp 200 volt . . 3/.89 8.14,16.18 Pin 5 for 1.00 Multimeter Kit incl. Power Supply $44.t6 cxnplete Leads 1000 MFD 30 Volt Electrolytic Cap Axial 6 Amp 600 volt .. 3/2.00 24 Pin & 28 Pin 3 for 1.00 Features: 0 to * 2, * 2 etc. up to y 200 volts DC 5 for $1.00 25 Amp 200 volts 3/5.00 40 Pin 2 for 1.00 Intersil CMOS Chip Set Accuracy to within 30

3 Amp 200 volt 3/100 High Noise Refection Non Critical Compo "en" s CAPACITOR ASSORTMENTS Contains: PC Boards, large .50 Fairchild Readouts All components, switches, complex fnsts. Popular value disc & low leakage up to & LED's & Specs including 1 MID 40 for $1.00 Jumbo Red LED's 10 for 1.00 100 for 9.00 Tubular Electrolytics Asst 25 Pk LED's Asstd Sizes & Colors 2.50 from 1 MID to 2000 MID 15 for $1.98 Bi -Polar LED Red /Green 1.00 SCR CITY Metal Can T0 -5 SCR Metal Can 1 amp 5CR POTENTIOMETER ASSORTMENT 1.6 amp 1 MIL Gate 10 Mil Gate

50 volt $.60 291595 . $.45 1K to 100K 12'6100 LED Kit - a $4.00 Value - $2.50 100 volt .65 2N1596 50 . .60 HELIPOT 150 volt ...... 70 2N1597 ..... Includes: Bipolar Red /Green 1- . Turn. 200 volt .90 2N1598 .... .80 10 Wire Wound Potentiometer Green, Jumbo 1 -Hi Intensity 3- 400 volt .90 2N1599 .90 500 Ohms, 5 Watts, 1/2 °% Linearity 98 $1 12 -Red Assorted 2- Yellow, Jumbo 4 -Panel Mounts Plastic T092 Package 6 FT LINE CORDS Plastic TO 202 Package SCR C 103 Series.

6 for $1.00 3 amp SCR C106 Series 30 volt . $.40 60 volt .45 5 volt, 6 Amp POWER SUPPLY KIT 15 volt .. $.30 30 volt .35 100 volt . .50 $12.95 complete .55 250K SLIDE VOLUME CONTROLS BY MALLORY 100 volt .40 200 volt 200 volt .50 Fixed: 6 Amp, 5 volt 1% Regulation 4/$1.00 300 volt .60 Metal T048 Stud Pkg Adjustable: 5 -12 volts Unregulated 400 volt .70 SCR 35 amp C35 Series Short Circuit Protection, Current Limiting Olf 25 volt $1.50 KIT INCLUDES: Heat Sink 50 volt 1.60 Filter Cap Transformer Comp. Grade Metal Press Fit Package 100 volt 1.70 2 AMP CIRCUIT BREAKER Output Power Transistors Regulator SCR 7.5 amp 150 volt 1.80 Front Panel Mount Through 1/2" Diameter Hole Capacitors Resistors 25 volt $.80 200 volt 1.90 120 VAC, 32 VDC. Trips at 2 7 amps 2 /$100 Posts Bridge Rectifier 4 Way Binding 50 volt .90 250 volt 2.00 Line Cord 100 volt 1.00 300 volt 2.20 Instructions & Diagrams Complete . 2.40 REVERSE REEL CONTACTS (AMP) 50/$1.00 200 volt 1.20 400 volt - 1 40 volt 2.60 300 volt 500 Ribbon Cable - 31 Conductor 2 Shielded Pairs, 400 volt 150 600 volt ...... 2.80 22 Guage Standard $1.99 /Ft. AMPLIFIER 8 SPEAKER MODULE 700 volt . 3.00 800 volt . 3.20 Impedance Matching Transformers $2.95 ea. Miniature Audio type 15 for $1.29 Not a kit - Ready for Mounting range DRY REED SWITCH capsules 2'd" Speaker, 8 ohm Adjustable Sealed amp 115 VAC 25 for 200 mw 12 volts Glass 5 $1.98 BIG -BRIGHT - .5" LED ALARM CM 6 DIGIT AC or DC or ELAPSED TIMER K T AC /DC WALL PLUG ADAPTOR- CHARGER RECTIFIERS $19.95 Complete 120 volt input 6 VDC 130MAioutpul $1.00 3 Amp Plastic Axial Leads 50 volt $.16 PC Board Drilled & Silk Screened (Includes Xt. I I are Base .18 100 volt Circuitry) 200 .20 COMPUTER PRODUCTS volt 5375 Nat Clock Chip & Fairchild Displays .22 volt . 300 Includes EVERY part required for clock and all ootic-s except 400 volt 24 PRIME, FACTORY, NEW Cabinet and Crystal Time Base components If desired, we below ALE 500 volt 26 for Brightness Control 24 Hr. Alarm wsrzlze 21102.1, RAM low power, 45 ons 8 $12.50 volt .30 600 Freeze feat on every mode 0 -60 Min Elapsed imer 1702A, EPROM Memory 1.5 ws $4.95 ea. .36 800 voll pe ea. Field Tested over 1 Yr. 12 Hr., 60 Ih 2708, PROM 1 k e 8 wv $21.95 .48 1000 volt Most Complete Instructions, schema'cs °ictorials. 8080A, Microprocessor 2 ws $9.95 ea. Important - PRICE BREAKTHROUGH! 3 Amp Axial Lead Glass Passivated layouts - everything for trouble tree assembly. 200 volt $.40 OPTIONS - 400 volt .45 XTAL Time Base Components $2.95 when purchasec v /clock 600 volt .55 Wood Clock Cabinet $4 00 when purchased w c'xx Terms and Conditions 800 volt .60 1 Amp Axial Lead Rectifiers Orders Shipped Within 24 Hours Hr. Version of Above 51795 Plastic Package 12/24 $5 00 Minimum Order Telephone C.0 D 's accepted except no Alarm or Elapsed Timer Any 10 for $1.25 $15.00 Minimum Bank Americard /MasterCharge order. 1N4001 194004 Add $1 00 Postage for orders under $10.00 194002 194005 Outside Continental U.S add postage - U S Funds. 1 1i:0o 1N4003 1N4006 Ni. Residents add 5% Sales Tau. Money Back Guarantee. (iIS 194007 ia.

CIRCLE 34 ON FREE INFORMATION CARD 93

www.americanradiohistory.com TELEPHONE recording equipment and other RECORDS- TAPESI Discount to 73%; all labels; 'unusual' electronic devices. Free information. PC BOARDS 11111 l'I RlVA I11. ti no purchase obligations; newsletter; discount GARRISON, Box 128 -B, Kew Gardens, NY dividend certificates; 100% guarantees. Free de- Our otsn 11354 tails. DISCOUNT MUSIC CLUB, 650 Main St., Dept. 3 -1177, New Rochelle, NY 10801 PRINTED circuit supplies. A process that always works. Send stamp. CIRCOLEX, Box 198, Marcy, solled e+.w.l NY 13403 xo,iAdn.en a6Ìe(5'k UNSCRAMBLERS - Several models that fit any Cash %A th order - " r, do n c e VISA r< scanner. Free catalog. CAPRI ELECTRONICS, NEWT Electronics catalog. Rush $1.00. Refund- Oh o res z4, t:<'mTrTr._, .,,H1Ncr 8753R Windom, St. Louis, MO 63114 able with first order. HOBBIE -TRONICS, 4950 Wadsworth,N'1eCZ' a92,I Clearwood Way, Sacramento, CA 95841 ELECTRONIC components, communication and test equipment. Stamp for catalog. E. FRENCH, RADIO & TV tubes 36e each. One year guaran- teed. Plus many unusual electronic bargains. Box 249, Aurora, IL 60507 EC-101 CURVE TRACER Free catalog. CORNELL, 4217 -E University, San STILL BY FAR THE LOWEST COST FOU FUNCTION Diego, Calif. 92105 ELECTROLYTIC capacitors top quality, reason- CURVE TRACER ON THE MARKET. ATTACHES TO able price, prompt delivery. Free brochure. TOUR SCOPE IN SECONDS. USED IT EDUCATORS, PROFESSIONALS ECOM PARTS DIV., 1007 E. Dominguez St., #F, AND HOBITISTS ALL OVER THE ASCII & BAUDOT picture tapes. Hundreds avail- WORLD. 30 DAT MONETRACR GUARANTEE. Carson, CA 90746 able, various lengths, subjects. Chad, no lids. 73

STILL ONLY COLO. RES. wide max. Perfect for teletype model 33, 15, 28, $ 39.50 Poo 3`v9Ì. telex, etc. Catalog for 144 stamp. 8-level Intro - FANTASTIC ELECTRONIC PLANS & KITS £0052 Pan SLES TAX pak (8 pix), $10.00. 5 -level intro -pack (10 pix), BRAIN WAVE MONITORS, RADAR DETECTORS, PHONE RE- $6.00. TELEPRINTER ART, LTD., 601 S. Dodson, CORDERS, SEE IN DARK, RADAR, SCRAMBLERS, SURVEIL- LANCE, ULTRASONIC ALARMS, AUTO ELECTRONICS TREAS- Urbana, IL 61801 URE FINDERS, LASER BEAMS, COLLISION AVOIDANCE, CB EQUIPMENT, HOME ELECTRONIC FACTORY. MANY, MANY MORE. SEND $1.00 FOR PLANS AND KITS CATALOG, PLUS 6 MONTHS SUBSCRIPTION ON LATEST ELECTRONIC DEVELOP- P.O. Box 4430E Santa Clara, CA 95054 MENTS TO: (408) 988-1640 ELECTRONIC DEVELOPMENT LABS Same day shipment. First line parts only. Factory DEPT. F BOX 1535 tested. Guaranteed money back. Quality IC's and PINELLAS PARK, FLORIDA 33565 other components at factory prices. NTEGRATED CIRCUITS MANUALS for Govt. surplus radios, test sets, Cif scopes. List 506 (coin). BOOKS, 7218 Roanne ELECTRONICS Drive, Washington, D.C. 20021 SERVICEMEN -Cleaners, lubricants, adhesives SHOAL PRODUCTS e 012 BO A58655865 S:upwa:sh Timer 9 DO for all electronic repairs. Write for free catalog. 7 50 - SeBUeN Mom Pu 27 PROJECTOR- RECORDER BELT CORP., Box [1526u95 EAneEe1 H00165syAUn 695 ] 01NIUnlauaal 176, Whitewater, WI 53190 414 -473 -2151 .. . , wMM. ePM2 MI ax+Me4 5- Al von Dc :o s M112 15.'62 . . " Iánr:á:i é ::e:n IEOOSTS CLOD, MÿOULES Hobbyists -Classified advertising '. o poor. COMPUTER únen2ö:,,5 ._, apa newsletter. Ads, new products, etc. Every 3 wks., ID SCOOTS , w Profile GI`IQÌii C.F. since Jan. 76. $3.75 /year. Free sample. ON LINE, iiâeéáá.°. M I WES. C p2 Én.50n 5-95 %Re1O p ury+eEdaeYJU 9:-' . ^ - t92P3 Tr,n,io,mer 2.15 5°GO CRYSTALS 4 -24695 Santa Cruz Hwy., Los Gatos. CA 95030 < 16 ié l3 ros, MAOIOA.CnFdA'1.95 OOx O2000MNr T 727 6 '0 a6 58 75 r25 18 27 0 61 IT1nnelpnneM eM IM]909N i MHO 4 25 125)6 MN,H' 7 50 50eï 10 22 35 5 MHz 4 25 3 22613 MHz 2 50 ,I, 4MIIeAee YAen 99 1 n,i.n xno 9op 10 177717 425 526133MHa 450 OurtMeeOMlmeSule 2.95 99 4 NE550N a9 412 MA1WgeerOme:uM11SO MICRO MINI MIKETM R MICROPROCESSOR NMHT 193 4231t 59 6600 24 50 12 MHT 16 55J6 MH, FaIr CS 6052.63 9 95 WIRELESS MICROPHONE OSMEMORYRAM 1+ 5,0 :X: +B'13MW+15 6000AwnnBata DISPLAY LEDs 280 39 95 '286eH4]2MH,450 18 433 MH, 450 0 MAHN+ CA ]70 90 World's smallest; solid state, self- contain- 50 4 50 90 81 l 5'95 WE 22 'N Milt 39 q2 ed. Picks up and transmits ME,630002MI MA]} Ce25OD 00 most sounds IN . ., 9Z:2 e CC 3W 00 without wires up to 300 ft. through FM Ra- "3n8 300 25 dio. Use as mike, ampf., alarm & 1HAxSSO13MFPS ói ö OF 70713 LA 300 00 alert sys., ws 06227 CA 500 W hot line, baby sitter, etc. Money back guar. +Ii3ñ 55 01.747 CA CO 95 129811 1 65 OL750 CC 6CO3 95 B A, M, C cds, COD ok, $18.95 plus $1.00 1N 56 '::.:-N ro post. & hdlg. Calif. res. add tax. Mail orders A to D CORwRTERV 00 15 670094 O95 .D503 CC SOO SC SIZE only. Oty. Disc. Avail. AMC SALES, CA 500 W INC.. 74t.500 TTL 570194 220 F.510 0750G 13 9` :5.800 « eW 220 o" _" Dept. 19. Box 928 Downey. Calif. 90241 BW 1Ì5 5ÓN j5 14Ó 1117111 1504Ñ 25 94WWVlpE 8M'p+esuM CMOf + 75

,,11 Pdp:aY : 69509N 25 c01402 Ean 50 W )415+3N 25 SiN6992:OnfU/SPAY fio ux 40 Có;°° sux A+6M'poanOw,ePPO áNB, pnmawlM1 Nam SIn EIeROY OUR 3:91 13 ti2ON 39 ^ .J5NnMipn0ly2el0CAUlu .522N 10 OLUMC'Ana1Y2e,NII + cc^-¡ 1.528N .. 10 Mrew10OA 100 Gbnea,OlOeL WJ6 4 gm, n-s.n1 V ON0, Digital Thermometer $48.50 60 Hz Crystal Time Base Home Alarm Kit $18.75 Designed for use with electronic siren Batt. oper. general purpose or medical Kit $4.75 Converts digital clocks module. AC power, 32'- 230'F. Disposable probe cover -2" from AC line frequency to crystal time battery backup, entry/ accuracy. Comp. assy. in compact case. base. Outstanding accuracy. Kit includes: exit delay. Instant alarm for night use. PC board, MM5369, crystal, resistors, NO /NC circuits. Test and arm indicators. Not a Cheap Clock Kit $14.95 capacitors and trimmer. 2 amp switching capability. All parts with complete instructions Includes everything except case. 2 -PC minus power sup- Electronic boards 6 -.50" LED Displays. 5314 clock New Cosmac Super 41ELF11 ply. siren module kit. S2.75 chip, transformer, all components and RCA CMOS expandable microcomputer full instructions. clock kit with .80" w /HEX keypad input and video output for Stopwatch Kit $26.95 Same THE MODS F ADDS DIGITAL YIME DISPLAY TR YOUR -Z Full six digit battery operated. 2 -5 volts. displays. $21.95 graphics. Just turn on and start loading PROGRASCREEN. iY AS FEATURED IN JULY RADIO ELECTRONICS.VERTICAL. m your program using the resident monitor 3.2768 MHz crystal accuracy. Times to PROGRAMMINGT EDISPLIYC AUDE: HORIZONTAL VERTICAL LOCATION OF THE DISPLAY DISPLAY FREQUENCYECONDS DIS TO 10 MIN.1 59 min., 59 sec., 991/100 sec. Times std., Digital Temperature Meter Kit on ROM. Pushbutton selection of all four DISPLAY FORMAT 112 OR 28 HOURS) SECONDS DISPLAY SUP- LL Z split and Taylor. 7205 chip, all compo- PRESSION DURATION OF DISPLAYAU %I LIARY INPUT FOR TEMP Indoor and outdoor. Automatically CPU modes. LED indicators of current nents minus case. Full instruc. White or switches back and forth. Beautiful. 50" CPU mode and four CPU states. Single COMPLETESKIT PWITH (INSTRUCTIONS $29.95 SHIPPING D INCLUDING CIRCUIT BOARD, TRANSFORMER AND 50 COMPONENTS H LED readouts. Nothing like it available. step op. for program debug. Built in pwr. black plexiglass case. $5.00 v Needs no additional parts for complete, supply, 256 Bytes of RAM, audio amp. 8 EOR INFORMATION ON OTHER CLOCKS AND GAMES WRITE TO .04.4 Z full operation. Will measure - 100` to spkr. Detailed assy. man. w /PC board 8 2.5 MHz Frequency Counter Kit air or -200F. liquid. Very accurate. all parts. Comp. Kit $106.95 Custom As low as 10 Hz . .50" digits expandable Complete instructions. $39.95 hardwood cab.: drilled front panel 19.75 w /PC board, parts 8 full instruc. $37.50 Nicad Battery Backup Kit w/all parts 4.95 Fully wired and tested $57.50 SAVE ;ó 85% BIG, Equipt.Catalog Clock Calendar Kit $19.95 Fully wired and tested in cabinet 151.70 Power supply kit (incl. PC board) $8.50 CT7015 direct drive chip displays date 1802 software xchng. club, write for into GOVT SURPLUS and time on .6" LEDS with AM -PM indi- 30 MHz Frequency Counter Kit- and NEW EQU1P'T cator. Alarm /doze feature includes buz- RCA Cosmac VIP Kit 275.00'. Same basic CMOS counter as above plus Coin at zer. Complete with all parts, power supply Stamps Video computer with games and graphics. level controls and dual FET inputs. Pre- Powerful Battery Motor and instructions. less case scalable to 200 MHz with PC board and 5 MOTORING MONK TAI, nC LOWIST full instructions $47.75 MUCH SeP1eS (DIRE Original Cosmac 41ELF11 kit ON ., $29.95 1977 IC Update Master with PC board, monitor, power supply Fully wired and tested. $67.75 Manual Complete integrated circuit plus all parts and instructs. $89.50 Power supply kit (incl. PC board) $8.50 Board only 14.95 Normal Remol data selector from all manufacturers. Ca, Imo Beauty. 1.234 page master reference guide to Auto Clock Kit $15.95 the latest IC's including microprocessors 41/2 Digit DMM kit $85.00 DC clock with 4 -.50" displays. Uses and consumer circuits. 17,000 cross Volts -ohms -milliameter accuracy ±1 National MA -1012 module with alarm references for easier sourcing of hard to count. Ranges: Volts -2, 20, 200. Ohms option. Includes light dimmer, crystal get parts. Special pricing: $24.95, with -2K, 2meg, 20 meg. Ma -200, 2000. timebase PC boards. Fully regulated, free update service thru 1977. Domestic .4" display. Variable update rate. Comp. comp. instructs. Add $3.95 for beautiful COMPACT 12 V. Ieunu TOR OBI 1V1TR AS29E 162,08 `postage $2.00. Foreign $6.00. w /parts, PC boards, instructs., less case. dark gray case. Best value anywhere. TERMS: min. order U.S. Funds. Calif residents add 6% tax. $5.00 FREE: Send for your copy of our 1977 Lincoln, Nebraska BankAmericard and Master Charge accepted. SURPLUS CENTER P.O . eo, 82109 OUEST CATALOG. Include 134 stamp. Zip Code 68501 Shipping charges will be added. CIRCLE 33 ON FREE INFORMATION CARD

www.americanradiohistory.com BAUSCH & LOMB V CONCENTRATION COMPUTER

BURGLAR /FIRE ALARM CONTROL CENTER

WORTH 10 TIMES OUR LOW PRICE! Bears B & L Part No. 33- 27 -55. An electronic analog computer which auto calculates the concentration of substances in solutions being analyzed by a s tometer. Designed for use with B & L Spectronic 20, Spectronic 600 and the r spectrophotometer. Adaptable to other spectrophotometers with full scale p Cages within the range of .5 volts to 20 volts DC. These are brand new units pacxaging complete with detailed instruction manual. We can also send you a the 30 page instruction manual for $5 (non refundable). Order ETCO No. SU2S D INSTALL AN ALARM- PROTECT YOUR HOME OR OFFICE! Manufactured exclusively tor ETCO and sold direct to you at the lowest possible price. Sophisticated features; provides one parallel fire and two series intrusion loops- instant re I rit we plastic and delayed (for keyless entry /skit). All relay operated - insensitive to static burst or li- Transparent, sound r f h ng distan- ghtning. When attacked. delivers 12 VDC @ 1% A. to external bell or siren (automatic 6 GIANT 22" "dishes" for construction ound pro- Minute timer built in). Parallel fire loop can be utilized for smoke alarm, panic button, ce parabolic microphones and PARABOLIC fall, designed fbor mat, ultrasonic sensor, photoelectric switches, etc. System status light indicates op- jectors. Reflector was esp.. MICROPHONE to provide hick gain audio car'ure capa - en door or window. 110 VAC operation capability - with auto switchover to internal bat - Microjhone cor,t en ion ideas tary in the event of power failure. Will operate on 12 V dry cell or rechargeable battery REFLECTOR bility. inclun MPS 330. (trickle charger built in). Compete with detailed instructions. (Accessories and battery 1995 extra). AL048D.

No. 41 LIGHT BULB BONANZA!

Imagine less than 4c each when you buy 1000. Brand new Phipps 4 nventory.. 2.5V, .5 Ci', T -3Z 100/$4.95 : alb, mini screw base. 6B033D. 6 1000/$39.95 ETCO Super Deal - 6 NYLON ALIGNMENT TOOLS! Longest is 10 /," and shortest 6" dia. 8 -TRACK BELTS 294 is 4". Commonly used types TR121D for FM / AM/ TV alignment. TLOO4D. 69T / 2N4339 F.E.T. WR024D 60 conductor ribbon wire 29c ft. N-channel. equiv. ECG133 294L TO -3 TRANSISTOR SOCKET PTO11D 25 radio push on knobs .. 69c DS157D 100/19.95 -sw ' XT010D 3579.545 precision color xtal ...99c RCA 370A 40 watt POWER 29 PT252D 6 asstd. transmitting xtals . $1.99 TRANSISTOR - 4 OP263D 5 asstd. optical lenses $1.98 DS160D 100/$3.69 trz 4' MS055D 1000/$29.95 PT059D 40 ft. asstd. insulating spaghetti ...... 99c 1.5A/200 Volt BRIDGE 50 assorted PT030D 10 asstd. Vector tube sockets ... 99c RECTIFIER - 20 pos. / 4 pole J -B -T switch . $3.95 DS159D 694 1 %PRECISION RESISTORS SW162D rotary Great for labs, schools, hobbyist CG077D Popular Ronette mono turnover cartw.ce ... 99c and researcher. All Y. or % watt, all PHILIPS AC787 /A1110.. SU212D 590 -670 tnH adj. hi -Q filter coil ... 99c Pair transistors w/ neat sink;. 1% or better. All are resistance and pl tolerance coded. Prime factory PT168D SP023D Underwater speaker/mike 8 ohms ... 99c r surplus inventory. PT069D. 99 SU229D 3 -cond. retractile telephone cord ... 29e 7A /600 Volt SCR (TO -661 THREE TRANSISTOR AF AMPLIFIER TR092D 3'/." plastic tape reel 14e '99 What a price! Brand new - ship- DS158D SP061D 1 -5/8" square 8 ohm micro speaker .. . $1.49 ped with schematic - lots of uses! For Hi Z input, 8 ohm output. SP095D 1- 1/16" dia. 8 ohm full range spkr.. . .$1.29 xtal phono or mike cartridge. The NE 2 NEON BULBS 10k control alone is worth our SU267D Quasar varactor UHF tuner . .$2.99 BB125D low price! Operates well on 6 vdc. 71 PK032D. 100/539.95 MEIN= _ MIN _.1.11__ THERMOSTATIC APPLI- - WE DON'T PRIME IC'S RUSH $1.00 toe ETCO ELECTRONICS, Dept. OW, ANCE SWITCH - SUO11 D 696 7 KNOW WHAT THEY ARE! 521 5th Ave., NYC, N.Y. 10017.

(t 100 asst. METAL FILM 64 PAGE BARGAIN- PACKED CAPACITORS PT167D SURPLUS CATALOG!

11' For PC board mounting Thousands of exciting surplus items and hare I $199 indust find parts for OEM, schools, hobbyist and FREE COPY with each order from this ad. $1; n 10 asst. THERMISTORS 149 PT1660 10/514.95. NAME Brand d "METRONIC" and bearing -- QUANTITY PRICES numbe below. A bargain for someone "who vows ". 18 pin package. ' ADDRESS OEM's / Manufacturers / Distributors: Metro is ML567 DS085D. Special wholesale quantity prices. M L167 DS086D. quantity desired for quote. Metro is Write listing Metronic ML667 DS087D. IM M. ME MIN CANADIAN U.S.A. MERCHANDISE SUBJECT TO PRIOR SALE. 'RICES MAIL ORDER MAIL ORDER SUBJECT TO CHANGE WITHOUT NOTICE.. CENTER CENTER Full remittance with each order, os BANKAME' CARD, 183G Hymus Blvd. 521 Fifth Ave., MASTERCHARGE, VISA, or CHARGEX. Add 5% for Pointe Claire, New York, postage and handling. (excess refunded). Please try ELECTRONICS Quebec H9R 1E9 N.Y. 10017. to bring your order total to $10.00 or more.

CIRCLE 28 ON FREE INFORMATION CARD 95

www.americanradiohistory.com NOW! 1 CARBON film resistors-1W, 5% (1-4M7 ohms) DON'T MISS ANY 3.5d each. 50 /value -$0.85. Postage, handling Get every single issue of Radio -Electronics The PTX $1.00. Other components. Free catalog, resistor sample. COMPONENTS CENTER, Box 295R, delivered right to your door, and before it Logic Probe West Islip, NY 11795 appears on the newsstand. Use this cou- Only $12.95 pon and subscribe now. and a new PARTS! mye CORNEL Low Cost p Send For Mail to: Radio -Electronics CORNELL'S SUBSCRIPTION DEPT., P.O. BOX 2520, Board New Color per BOULDER, COLO. 80322 tube ORDER FREE All of our boards feature- CalogtaNew - - If NOT SHIPPED rr Items IN IN 74 HOURS Numbered tie points and colored plugs. LOTS OF 100 Solid printed circuit boards. 4215 E IE O CALIF. 92105 name (please print) Reusable parts. Our original board handles 10 IC's in sizes from 14 -40 pin DIP shown above. Kit includes: Burglar . Smoke address Board, plugs, sockets & eyelets. Only $36.25 - Order # 141 Fire Alarm Catalog NEWfrom Printronix- a very /ow cost board! city state zip code Our new board can handle 10 IC's and included Billions of dollars lost annually due with the board are sockets, plugs, even wire. to lack of protective warning alarms. check offer preferred Only $12.95 -Order # 171 A complete package for the Experimenter FREE CATALOG Shows you how 1 Year issues ONLY $8.75 to -12 including one of the above PTX kits and 3 specially selected books: Basic Digital Elec- protect your home, business 2 Years -24 issues SAVE MORE $16.50 tronics, OP AMP Circuit Design and Applica- F1R7 and person. Wholesale (You save $7.50 over newsstand) tions, Optoelectronics Guidebook -with tested a:oc. prices. Do- it- yourself. Free projects. With kit #141- $49.95 -Order #151. 3 Years -36 issues GREATER SAVINGS $24.50 With kit #171- $26.95 -Order # 181. engineering service. (You save $11.50 over newsstand prices) Also New- a low cost logic probe! Good for TTL & C MOS integrated circuits, Payment enclosed Bill Me includes VLED's and case. Kit- two $12.95- Box Order #271 82802 RE -127 Lincoln, Ne. 68501 Check here if this is a new subscription Assembled -$17.95 -Order #261 Check here if you are extending or renewing Books of interest! WANTED your subscription Programming Microprocessors -Order #985- $6.95. Master Handbook of 1001 Practical RADIO -TV jobs- stations hiring nationwide! Free Electronic Circuits -Order #800 -$9.95. Micro- details: JOB LEADS, 1680 -CN Vine, Hollywood, Canada same as U.S.A. Extra Post- processor /Microprograming Handbook -Order CA 90028 #785- $6.95. Computer Programing Hand- age: Pan American $1.50 per year, book -Order #752 -$8.95. SEEKING Japanese Transistors for CB and ster- eo repair? Request complete list. 1 all other foreign $2.00 per year. PRINTRONIX ALL items are postpaid Compare to 9 N.Y. City & State prices: 2SC710 .59, 2SC517 3.95, 2SC799 3.60, 1361 Flatbush 40J7 Ave. residents add tax 2SC1306 4.40, 2SC1678 2.25, TA7205P 3.90, Bklyn, N.V. 11210 BA521 3.70, BA511 3.40. FUJI -SVEA ENTER- PRISE, Dept. RE, P. O. Box 40325, Cincinnati, OH CIRCLE 11 ON FREE INFORMATION CARD 45240

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CIRCLE 31 ON FREE INFORMATION CARD

www.americanradiohistory.com DIGI-KEY TOLL CORPORATION 1- 800 -346 -514 Quality Electronic Components FREE

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Norme A9MrdT-1..11mr 7415366 .67 LM320MP-5 1.30 .21 w/Me.INw.al4allR 61400/100 7408 7415367 .67 L16320MP6 130 8212 8.810 I/O PORT S 3.95 7409 .21 7415368 .67 IM320MPß 1.30 8216 81- DIRKTIONAL BUS DRIVER S 4.25 7410 .21 741500 .28 7415377 1,50 1.M320MP-9 1.30 8224 CLOCK GENERATOR S 3.95 5% CARBON FILM RESTS 7411 .21 741501 .28 7415386 .39 5M320MP-12130 8228 SYSTEM CONTROLLER S 6.95 7412 .21 741502 .28 7415395 1.74 111320MP-15130 u WATT RESISTOR ASSORTMENTS 512.95 7413 .25 741503 .28 7415670 2.34 IM320MP-18130 8251 COMMUNICATIONS INTERFACE 7414 .89 ..°... 741504 .29 81LS95 .77 VA320MP-18130 8255 PERIPHERAL INTERFACE 511.95 7416 .25 741505 .29 811596 .77 LM320MP-24130 1702A 2K EPROM (256.8) S 6.95 "19.90 7417 .25 741508 .29 6125 ee::ÿ,.ó:.m« . 811597 .77 1M323K 7.50 2708 8K EPROM (140x8) 529.50 7420 .21 740509 .29 19.90 811598 .77 11132414 .72 RS2S5.w,i'i.. ;`ana... diao`..a' ' 7421 25 741510 .28 2102-1 1K RAM 500 NS S 1.79 1M325N 2,70 1S WATT REfMTOR ASSORTISSES 7423 E SC /MP 5 VOLT SC/MP CPU S 9.95 .35 741511 .28 I NT RFA CI 1M326N 2.70 7425 .35 741512 .28 MICROPROCESSOR 1.25 MH -2 CLOCK 40 DIL 524,95 .40 1M327N 2.70 2650 rw 7426 .25 741513 .47 8093 .40 1163398 1.15 PATENTED CHROMAFKTER SCREEN, DE CAST METAL FRAME .u.a.,i 7427 741514 1.02 8094 6150 '.o.i°ii.i Tó.w. w~ré. 19.90 .28 8095 67 LM340T-5 1.25 WIRE WRAPPING WIRE IN BULK MOUNTS IN PANELS UP TO 3/16" ma, NO EXPOSED 7428 74/515 .28 1M340T6 1.25 59.90 7430 .21 8096 67 HARDWARE, SCRATCH RESISTANT AND EASILY CLEANED, 62506.1'1.í3ú`óu',6..pwnourrwwé 741520 .28 1M340Tß 1.25 Red a. Block 30 ga. ynor 7432 .25 741521 .28 8097 .67 ELIMINATES GLARE. U13407-10 1.25 1000 71 S.CG 7433 .30 741522 .28 180' 52.00 500' 58.50 1M3400-12 1.25 MOUNTING ADAPTERS AVAILABLE TO SIMPLFY MOUNTING 7437 .25 741526 .33 75450 88 .61 LM2407-15 1.25 AND ASSURE PERFECT ALIGNMENT. 7438 .25 741527 .33 75451 75452 .61 LM3407-18 1r25 5% CARBON FILM RESISTORS 7439 50 741528 .33 LM3407-24 1.25 400 BEZEL WITH RED FILTER 49E 4Yt. .21 75453 .61 7440 741530 .28 420 MOUNTING ADAPTER FOR MA1001 B MA1002 .. , 509 75454 .61 LM341 P-5 .98 Y. A WATT SIZE lergrh 7442 .53 741532 .33 ' 421 MOUNTING ADAPTER FOR MA1010 .69 75491 .81 LM341 P6 .98 Our Cat0Iog .70 741533 s 133 s 7445 .33 C., 1.7' LM341 Pß .98 60064. 5' Pn/.o66 7446 70 741537 .33 75492 .84 For Mer. 75493 1.09 5M3419-10 .98 1000 - /,. be 1.2... 7447 .7o 741538 .33 Diamond Toe; 75494 1.19 LM341 P-12 .98 CLOCK MODULES 7448 .70 741540 .28 MC1488N .90 111341P-15 .98 PLESSET SAMPLER ACE 7450 .21 741542 .67 TM1. M41002 od 1M1010 unes dad nodules by 844 id 5nicen61Xr a. 200-K MC1489N .90 148341 P-18 .98 e 4 110 d'eeby on 805 7451 .21 741547 .79 METAUIED POLYESTER CAPACITORS lolly assembled ad ,al.d ,bá, coing del, d L113419.24 .98 AN ASSORTMENT Of 7453 .21 741548 .77 '18$ 1M348N 1.60 526.00 1 an ,bd. 7454 .21 741551 28 300 CAPS 18 VALUES edywla.eofvhMSM*, 1M3498 1.60 dada 7460 .21 741554 .28 4000 Thiko 1483588 .72 WiWilliam d6eoY adrynitim'p bm none men Pous 7470 741555 .28 4001 .23 CAPACITORS ghh oc'= LM1310N .84 METALIZED POLYESTER h prier, b a. ber a abr paMN6 a. n ep.,a,n 46N han 11 7472 Ó 741573 .39 4002 .23 three btnn 0191-5.y Stocks 1.111130014 .94 033 ..15 1.25/10 10.00/C mes OC ,o na Xetvr M needed..ded. Our Plo. iabdn pell 7473 30 741574 .39 4006 113 001 . .14 1.15/10 9.00/C tM Fnt1n LM18018 1.70 9.00/C 047 ..15 1,25/10 10.00/C sondes ta ,.n.e M m.. 7474 .30 741574 .39 4007 .23 0022 .14 1.15/10 A, Lino 11,618128 4.80 1.15/10 9.00/C 068 ..15 1.25/10 10.00/C 7475 .49 741575 .53 4008 .79 0033 .14 .5" 102 12 Men 41414 Cbe MduM 40.50 LM1830N 1.30 1 ....17 1.35/10 11.00 /C MA1002A 7476 .32 741576 .39 4009 .44 LM18898 2.00 1.85/10 15.00/C iSET Md4M.nb TamFarerl5nea .- '13.95 7480 .7o 741578 .39 4010 .44 W68 .1 Ì 1.15//1 Ó 9.0OU0%C n...23 MA1002A 11121118 1.25 33 ...30 250/10 20.00 /C 7483 .70 4011 .23 01 . . .14 1.15/10 9.00/C UD 24 Mao Clee k1duM '10.50 I142907N 1.50 47 .36 /C MA1002C .r' 0 .. 3.00/10 24.00 7485 .89 746585 .49 4012 .23 022 . .15 1.25/10 10.00K LM2917N 1.50 MA1002C SET MduM.7Ta,tamr4S.ncle '13.95 7486 .28 741586 .39 4013 wwap..lMr .., S5.95 1.M3089N 1.30 7489 2.19 711590 .57 4014 .96 ELECTROLYTIC CAPACITORS MA1003 12 r4n Ca Cbe .im sn0es '24.95 1M3900N .88 vrw-33MS56e.;. 56.95 7490 .41 741592 .57 4015 .96 111/39003 .88 MA1010A .M" U0 121wr ABPM COOK Module 43.00 7191 .70 741593 .57 4016 .40 VALUE RADIAL LEADS AIIAL LEADS STRIPS W 7492 .44 741595 .88 4017 1.05 47/509 08 .65/10 5.41/C .11 .90/10 7.65/C MA10104 SET MduM wRanbmw 6 SwiMN, '16.45 4018 1,05 11M9Ñ 1. .¢ 7493 .44 741586 .88 1/509 08 .65/10 5.41/C .11 .90/10 7.65/C 1M3911N 1.50 MAIO10C w- LED 24 Men COI* Nodule '13.00 7494 .70 7413107 .39 4019 .23 08 5.41/C .12 .90/10 7.82/C SILICON TRANSISTORS MC1456V 1.00 2.2/509 .65/10 45 7495 .70 7415109 .39 4020 1.14 .12 1.00/10 8.31/C MA1010C SET MduM w?mnslpmo 8 Seichs '16 MC1458V .53 3.3/509 08 .65/10 5.41/C MPS918 16 155/10 13 609 130.00/M 7496 .70 7415112 .39 4021 1.14 7.91/C MC1496N .70 4.7/359 08 .65/10 5.41/C .12 .95/10 MP5930 16 1.55/10 13 6041 130.00/M 74100128 7415113 .39 4022 .96 .12 1.00/10 8.31/C MC3302P 1.15 4.7/509 08 .68/10 5.75/C High Digits MP52222A 16 1.55/10 13609 130.00/M 74107 .30 7415114 .39 .90/10 7.65/C NE536T 2.50 10/169 08 .65/10 5.41/C .11 pip02 MPS2369A 16 1.55/10 13 609 130.00/M 74109 .33 7415125 .49 402444 44 8.31/C NF5401 2.04 10/25V 08 .65/10 5.66/C .12 1.00/10 M M952907A 16 135/10 13 60n 130.00/M 74116 1.26 7415126 .49 4025 1.10/10 8.94/C NE555V .18 10/359 09 .70/10 6.12/C .13 48953393 16 155/10 13 60/. 130.00/48 74121 .35 7415132 .81 4026 168 1.15/10 9.56/C NE556A .88 10/509 10 .75/10 658/C .14 N953393 16 1.55/10 13 604 130.00/M 74122 .44 7415136 .39 4027 .40 .13 1.00/10 8.31/C NE558N 2.40 22/169 OB .67/10 5.66/C MP53391 16 135/10 13 60+ 130.00/M 74123 61 7415138 .73 22/259 09 .70/10 6.09/C .13 1.05/10 8.74/C 7415139 .73 4028 7.89 NE559N 2.40 48953395 16 135/10 13 60 130.00/94 74125 .40 22/359 11 .85/10 7.29/C .15 1.19/10 9.98/C 4030 23 NE5606 2.50 48953563 16 155/10 12 604 130.00/M 74126 .40 7415151 .75 22/509 12 1.00/10 8.48/C .17 1.32/10 11.22/C 1033 1.51 NE561B 2.50 M953565 16 155/10 12 60/' 130.00/M 74128 .48 7415153 .75 .12 1.00/10 38. 33/169 09 .75/10 6.90/C 8.48/C 74132 70 7415154 1.10 4034 330 NE5628 2.50 482536384 16 15500 12 601+ 130.00/M 33/259 10 .81/10 7.50/C .14 1.15/10 9.56/C I 1.14 NE5651 1.25 W03640 16 155/10 13-.60 : 130.00/M 74141 .88 7415155 .75 4035 1.34/10 11.23/C .. 4040 1.14 NE5669 1.28 33/359 13 1.05/10 9.65/C .17 MP53641 16 155/10 1.1401 130.00/M 74145 70 7415156 .75 14 1.13/10 10.41/C .19 1.52/10 12.89/C 7415157 .75 4041 .79 NF567V 1.36 33/009 5D0. MP936/3 16 155/10 12x607" 130.00/M 74147 1.63 47/109 09 .71/10 6.52/C .13 1.04/10 9.50/C 6c9ea1 7415158 .75 4042 .79 UA709CV .41 243904 16 155/10 12560/" 130.00/M 74148 1.30 47/169 10 .81/10 7.47/C .11 1.15/10 9.56/C 7415160 1.02 4043 .70 UA710CA .44 213906 16 135/10 1260/" 130.007M 74150 1.16 47R5V 131.05/10 9.65/C .17 1.30/1011.22/C 7415161 1.02 4044 JO UA711CA .53 H¡ghDlg 234124 16 1.55/10 1260/' 130.00/M 74151 .70 47/359 14 1.13/10 10.41/C .19 1.51/10 12.89/C 74153 65 7415163 1.02 4046 1.86 06723CA .60 2144126 16 155/10 13e0/ - 130.80/M 45/509 15 121/10 11.16/C .21 1.71/10 14.55/C MAl010 1.03 7415164 1.02 4049 .40 11A733CA .75 234401 16 1.55/10 1360/" 130.00/M 74154 100/109 10 .77/10 6.58/C .14 1.13/10 936/C " 74155 .70 7415168 1.14 4050 .40 UA711CV .44 2944403 16 155/10 13601 130.004M 100/169 11 .85/10 7.28/C .17 1.30/10 11.22/C 7465169 1.14 4051 1.26 UA717CA .70 a Tt:r'J1 2N4410 16 135/10 1240. " 130.00/9A 74156 JO 100/259 13 1.10/10 9.15/C .20 1.55/10 13.30/C ' H T 74157 JO 7415170 1.73 4052 1.26 UA748CV .49 2945087 16 155/10 0.60. - 130.00/94 100/359 17 1.41/10 11.85/C .25 1.93/10 16.50/C 74160 .88 7415173 1.34 4053 1.26 UA7805CU 1.25 285089 16 155/10 111.60 - 130.00/M 100/509 21 1.71/10 .29 2.30/10 19.70/C - 1.06 4060 1.58 067806CU 1.25 1/55/C r." 16 155/10 17._943, 130.00/M 74161 88 7415174 12.05/C -1 . 235210 220/109 13 1.08/10 9.15/C .18 1.42/10 74162 .88 7415175 .84 4066 .79 06780800 1.25 n 233055 99 9.20/10 8".00 - 800.00/M 220/169 15 1.16/10 986/C .20 1.55/10 13.30/C 74163 .88 7415181 2.50 4071 .23 1167812C1) 1.25 MPF102 .36 3.35/10 3:.60." 300.00/M 220/259 21 1.71/10 14.55/C .29 2.35/10 19.96/C 74164 .96 7415190 1.18 4072 23 067812011 1.25 285457 48 450/10 4;.00 " 400.00/M 220/359 25 2.03/10 17.26/C .35 2.79/10 23.70/C 74165 1.15 7415191 1.18 4073 23 UA7815CT1 1.25 .. 4895013 28 2.60/10 24.00 230.00/M 19.96/C .40 3.33/10 27.44/C 74166 1.15 7415192 .98 4075 .23 UA781801 1.25 220/500 29 235/10 iiáiii=,.i1.7S' M2955 99 9.20/10 8...00 800.00/M 1.18/10 13.71/C Vse 115 74170 2.64 7415193 .53 4081 .3 UA782401 1.25 330/69 14 1.12/10 950/C .19 TIP120 99 9.20/10 8'..00 . 800.00/M 15 1.16/10 9.83/C .21 1.64/10 15.13/C iiii2iisistnpl 74174 .98 7415194 .88 4082 .23 0678105002 .40 330/109 21 2.45/10 22.70/C 74175 .93 7415195 .86 4502 .79 UA78106ACZ .40 330/169 1.66/10 14.14/C .31 . 15.79/C .38 3,07/10 26.38/C .AR .III 74176 .79 7415196 .86 4510 1.14 UA78L08ACZ .40 330/259 23 186/10 .43 3.43/10 31.68/C :::11 74177 -79 7415197 .86 4511 1.05 UA7811oACZ .40 330/359 33 266/10 24-59/C 330/509 54 4.30/10 39.73/C .60 4.81/10 44.45/C .85 8.20 /M 38.20/5M 27300 /50M 2-56 1/4 SC LM' .. .99/C 74180 JO 7415197 .86 4514 280 UA78112ACZ .40 /C 2-561/!SCaW' .,.99/C .40 470/69 15 1.21/10 11.16/C .20 1.61/10 15.13/C 74180 JO 7413221 1.06 4515 2.80 UA78L15ACZ 185226E 3.39 1352428 12V 4401/1SCLEW ...55/C 7465240 1.90 4516 1.23 DA78518ACZ .40 470/109 21 1.71/10 1455/C .31 2.45/10 22.70/C 74181 2.15 18522711 3.69 195243E 13V 440 1/11iCCW .. .60/C 7415241 1.90 1.14 0678124607 .40 470/169 23 1.81/10 15.39/C .33 2.66/10 2459/C 74182 .79 4518 1852288 3.99 185244E 14V 6-321/1iCtEW .. .65/C 7415242 1.70 4520 1.14 UA7905CU 1.70 470/259 29 3.35/10 19.96/C .43 3.43/10 31.68/C 74184 2.15 11152298 4.3V 1N5245B 15V 6-32 1/3 40 898 .. .75/C 74185 2.19 7415243 1.70 4527 1.68 UA7906CU 1.70 470/359 41 3.27/10 30.26/C .47 3.78/10 34.99/C 1852308 4.79 1852469 16V 832 3/1 SC 1EW . . .90/C 74189 3.50 7415244.1.70 4528 .88 UA7908CU 1.70 470/509 54 430/10 39.73/C .75 6.03/10 55.80/C 195231B 5.1V 135247B 17V 832 5/1 SC MW .. .99/C 74190 1.23 7415247 .79 4585 1.23 067909(9) 1.70 1000/69 n 1.90/10 1630/C .35 2.76/10 25.54/C 1N5232B 5AV 1N5248B 18V 2-561404 N -T 55/C 74191 1.23 7415248 .79 7 1.167912CU 1.70 1000/10V 24 1.96/10 16.62/C .38 3.07/100 28.38/C 1N5233B 6.09 1N524913 19V 4d0 1417c N -T 55/C 74192 38 7415249 .79 06791501 1.70 1000/169 29 2.35/10 19.96/C .43 3.43/10 31.68/C 1N523113 6.2V 1N525011 20V 6-32 1496 N -T 60/C 74193 88 7415251 .84 08791800 1.70 1000/259 42 3.33/10 28.27/C .68 5.42/10 50.13/C 1 N5235B 6.89 1N525194 22V 8-32H91N-T, 60/C 74194 .88 7415253 .84 06792400 1.70 1000/359 60 4.81/10 44.45/C .75 6.03/10 55.81/C .50 185236E 1352528 24V NO 2 L 2Of bASHER 85/C 74195 .88 7415257 .75 CUA 2200/69 36 2.86/10 26.48/C .43 3.43/10 31.68/C 73V 1N52378 1945253B 25V NO 4 L ](2 bASHER 45/C 74196 .88 7415258 .75 LF351N .76 2200/109 42 3.33/10 28.27/C .60 4.81/10 44.45/C MA1003..., '24.95 8.2V 1852548 27V NO 6 L 701 6ASHER 45/C 74197 .88 7413260 .34 503568 1.20 MM5314N 2200/169 54 4.30/10 36.58/C .68 5.42/10 50.13/C 1N5238B 8.7V 1852398 9.1V 1352558 28V NO S L Xx WSHER 454 I.C. SOCKETS IN5230B 10V 19452568 30V DOUBLE DIGIT DISCOUNTS SAVE YOU EVEN MORE! 1N52418 11V 1N5257B 33V 8 PIN SOLDER 17 1.60/1 14 PIN SOLDER 20 1.90/10 17.00/C VOLUME DISCOUNT A SILICON DIODES 16 PIN SOLDER 2.10/10 18.75/C HANDLING CHARGE 18 PIN SOLDER 2 9 2.75/10 24.50/C HANDLING VOLUME 161001 .64/10 5.50/C 549/M 20 PIN SOLDER 30 2.85/10 25.25/C All hems, except Bishop Grophlcs 1N4002 .66/10 5.60/C 5517M PIN SOLDER 3 3 3.15/10 27.75/C 22 and Ecalany Terminals moy be corn- DISCOUNT 1N4003 .68/10 5.80/C 552/M 24 PIN SOLDER 38 3.60/10 32.25/C CHARGES 1941001 .70/10 5.95/C $54/M bind for volume discount. Fist -total 28 PIN SOLDER 45 4.25/10 38.25/C S -S Add 52.00 -5 24.99 NET 1944005 .82/10 7.05/C $63/M 0.00 4.99... gems mid opply the S 0.00 40 PIN SOLDER 63 6.00/10 53.50/C all dhcoumablet 184006 .90/10 7.75/C 569/94 . 10% 8 PIN W -W 4 2.30/10 20.50/C S 5.00 -524.99... Add 50.75 volume discount, Then add to this sub - S 25.00 -S 99.99 Less 1944007 .99/10 8.60/C 577/M items. Add 14 PIN W -W 26 2.50/10 22.00 /C S 25.00 -549.99... Add $0.50 total the nandN000ntable S 100.003499.99 . Less 15% 1N4148 .40/10 3.50/C $29/M 16 PIN W 3 0 3.85/10 25.50/C the hondling charge. This is your total 60 5.70/10 51.00/C S 50.00- 599.99... Add $0.25 S 500.00. 5999.99 . Less 20% 18 PIN W -W cost pay all shippieg and im FREE CATALOG 20 PIN W -W 6.65/10 59.50/C samt ee to addresses in the U.S.A. o d 8. Up Less 25% 71.50/C $100.00 8 Up ... No Charge $1000.00 ... 22 PIN W -W 84 8.00/10 Canada. 24 PIN W -W 96 9.10/10 81.50/C DATA BOOK 28 PIN W-W 112 10.00 /10 95.20/C Phan. or Mall 1 Orders Accepted by TTL CC.'3 P 54.00 40 PIN W- 36 12.50/10 115.00 /C SI charge 592 BMKRMLRICARD MastrCharpe Dank-Americard COD Check Money Order LINEAR I.C.'s 952 P. 55.00 MOLEX I.C. SOCKET PINS P.O. -Boa 677, Thief River Fails, Minn. 56701 129e) 651.6674 CMOS 74C 555 P 53.00 Q POWER TRANSISTORS 151 P. 53.00 .85 /C 8.20/M 38.20/5M 275.00/50M MEMORY I.C.'s 592 P. 5300 MOS /LSI I.C.'s 713 P 5400 TIDE SWITCHES 50 VOLT DISCS INTERFACE I.C.'s 464 P. 54.00 REG 128 P. 53.00 PF VOLTAGE I.C.'s SPST .15 1.25/10 10.00/C 00 40/10 3.50/C LINEAR AP 1 432 P. 54.00 220 PF 40/10 3.50/C 470 LINEAR AP II 246 P 53.00 DP07.23 2.00/10 19.00/C PF 40/10 3.50/C DIGI -KEY AUDIO HANDBOOK 196 P 53.00 .001 UF . , , 40/10 3.50/C SPECIAL FUNCTION 53.00 STRANDED HOOK UP WIRE 0022 UF. .. 40/10 3.50/C CORPORATION SC/MP APPLICATIONS 55.00 .0047 UF. .. 40/10 3.50/C 8080A DESIGN 55.00 20 go PVC.. 2.50 /100' 10.00 /500 .01 UF 45/10 3.65/C FET DATAROOK 53.00 11.25/500 . 22 go PVC.. 2.80/100' .022 UF . . 50/10 4.00/C Quality Electronic Components CMOS 4000 278 P 53.00 24 go PVC.. 2.10/100' 8.50/500 .047 UF , . 70/10 5.60/C P.O. Box 677 Thief River Falls, MN 56701 (218) 681 -6674 ANALOG MANUAL 637 P. 55.95 26 go PVC.. 2.10/100' 8.50/500 .1 UF .. . . 1 35/10 11.50/C

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Acoustic Fiber Sound Systems 75 Digital Research Electronics I 1 1 76 Adelco 74 Electronic Development Lab 94 Advance Electronics 26 14 Electronic Warehouse 92 42 American Technology 79 26 Etco Electronics 95 65 AP Products 16 Fair Radio Sales 92 20 Avanti Research Cover IV 31 Fordham Radio Supply 96 64 B & K -Div. of Dynascan 14 74 Formula International 115 CIE- Cleveland Institute of 29 Fuji -Svea 110 Electronics 18 -21 44 Godbout Electronics 116 53 Communications Electronics SEE IN THE DARK 75 34 I lobbi-House 93 35 Continental Specialties 32 Information Unlimited 92 IR viewer complete ready to operate. CREI -Div. of McGraw -Hill Continuing Interfab 94 Guaranteed by the manufacturer. Education 80 -83 46 International Electronics 109 Portable, runs on lantern battery. 61 Dana Labs 87 16,17,47 James Electronics 106,107,116 New, see in total darkness. No ship- Digital Concepts 61 Lakeside Industries 90 ments to Calif. Comes complete with 3 Discwasher 67 Lab Science 94 built in IR source and adjustable 52 Edmund Scientific 77 71 LMN Electronics 91 focus lens. SPL -21 $199.00 51 EIC'O 88,89 23 Meshna 98 EMC-Electronic Measurements 73 CHARACTER GENERATOR CHIP 24 New Tone 114 Memory is 512X5 produces 64 five by seven 2 Enterprise Development 84 ASCH characters. New by National, w /specs 69 Olson 102 6 Fidelity Sound 86 $6.00 48 Optoelectronics 101 GEN 13 TOUCI-ITONE ENCODER CHIP 10 Page Digital 90 Compatible w /Bell system. Ideal for repeater 45 Grantham College of Engineering 89 work. W /specs $6.00 62 Parasitic Engineering 116 GTE-Sy lvania-Consumer Renewal 2 SMOKE FIRE ALARM 55 Poly Paks 105 - -INTRUDER 100 Ileath 28 -31 12 VDC w/5 inch loud bell, w /instructions. 11 Printronix 96 66 Hickok Electrical Systems 76 Fine biz. for car, camper, boat, home 33 Quest 94 W /instructions $20.00 9 Indiana Home Study 84 59 Radio Hut 113 CATALOG SP -10 NOW READY 22 Internation Crystal 85 30 Ramsey Electronics 104 customer paye all postage 18 James Electronics Cover Ill R JB Saunders 103 MESHNA, PO BOX 62, E. Lynn Ma 01904 Kenwood 27 SR SD Sales 112 56 Leader 17 38 Solid State Sales 111 CIRCLE 23 ON FREE INFORMATION CARD 12 Mountain West Alarm Supply 89 Surplus Center 94 7 National Camera 74 72 Texas Tuner 98 National Radio Institute (NRII -Div. of McGraw -Hill Continuing 60 West Side Electronics 90 TUNER SUB Education ('enter 8-11 National Technical Schools 62 -65 $19.95 77 OK Machine & Tool 22 57 Oneida Electronics 24 Since all tuner subs that we know of are modified 70 PAIA 76 TV Tuners, we decided to market an excellent 73 Perma -Power 69 performing yet very low cost sub for the technician MOVING? 37 Platt Luggage 73 who has to get all he can for his money ... a "Poor Boy's Sub" for only$19.95. 54 PTS Electronics 86 This was not an easy task since cabinets, knobs Radio Shack 1 Don't miss a and controls would push the price far above $19.95 27 Rye Industries 85 single copy of ... We searched for a tuner that needed no cabinet Sabtronics International, Div. of Euray Radio -Elec- and no controls ... one that the tech could scounge Trading 7 the knobs from most any old TV Sams tronics. Give ... H.W. 15 ATTACH It took over two years but we finally found it. The 39 Schober Organ 84 Us: gain is excellent ... Battery drain is very low (only 4 Sencore 77 LABEL 18 mils). It's self biasing so there is no R.F. gain 19 Sinclair 23 control to fiddle with ... It works equally well on Six weeks' no- HERE 63 Southwest Technical Products 5 tube or transistor sets ... b/w or color ... and is as 49 Spacekom 71 tice easy to use as starting a fight with your wife (well, almost). All you need do is hook the set's IF cable to 13 Tab Gooks 88 the "Poor Boy" and view the picture ... That's it ... 28 Telematic -Dis. of UXL 87 Your old ad- no set up controls to confuse you. 103 TK Enterprises 71 dress and zip We compared the "Poor Boy" with other subs 5 Tri -Star 86 costing over twice the price and found it to work just code 68 VIZ Mfg. 25 as well on a /)the comparison tests we made ... and 75 Wahl Clipper 79 often a lot easier to use ... Even though instructions 1 Weller -Xcelite -Div. Your new ad- aren't needed ... you get those too. of Cooper Industries Cover 1I The "Poor Boy" is small enough to easily hold in dress and zip 40 Wersi one hand ... no wires or controls dangling around. It 89 code comes completely wired and tested including bat- Market Center teries and ready to use. Send a check for only 36 Ace Electronics 114 $19.95, and we even pay the shipping (how about 67 Active Electronics 108 that ?) or we will ship COD. name (please print) 41 ADVA 108 Try it for 10 days ... If not completely satisfied Assembly Systems 94 ... return for full refund. AMC Sales 94 address ALL ORDERS SHIPPED THE SAME DAY RECEIVED!! 43 Babylon Electronics 102 Burdex Security TEXAS TUNER SERVICE 96 city state zip code 4210 N.E. 28TH STREET, Karel Banta 90 FORT WORTH, TEXAS 76117 CFR 90 Mail to: Radio- Electronics PHONE (817) 834 -8201 29 ('haney 104 SUBSCRIPTION DEPT., P.O. BOX 2520, Cornell 96 BOULDER, COLO. 80322 CIRCLE 72 ON FREE INFORMATION CARD

www.americanradiohistory.com NEW LSI TECHNOLOGY FREQUENCY COUNTER

CE STATE -OF- THE -ART COUNTER FEATURING THE TAKE ADVANTAGE OF THIS NEW MANY BENEFITS OF CUSTOM LSI CIRCUITRY. THIS NEW TECHNOLOGY APPROACH TO INSTRUMENTATION YIELDS ENHANCED PERFORMANCE, SMALLER PHYSICAL SIZE, DRASTICALLY REDUCED POWER CONSUMPTION [PORTABLE BATTERY OPERATION IS NOW PRACTICAL], DEPENDABILITY, EASY ASSEMBLY AND REVOLUTIONARY LOWER PRICING! ÿ( KIT #FC -50C 60 MHZ COUNTER WITH CABINET & P.S $ 1 V9COMPLETE! KIT #PSL -650 650 MHZ PRESCALER NOT SHOWN] 29.95 MODEL #FC -501NT 60 MHZ COUNTER WIRED, TES ; CAL. 165.95 MODEL #FC- 50l600WT.. 600 MHZ COUNTER WIRED. TESTEti' 199.95 SIZE: fC411 3" High 6" Wide 51/2" Deep FEATURES AND SPECIFICATIONS: DISPLAY: 8 RED LED DIGITS .4" CHARACTER HEIGHT GATE TIMES: 1 SECOND AND 1/10 SECOND PRESCALER WILL FIT INSIDE COUNTER CABINET RESOLUTION: 1 HZ AT 1 SECOND, 10 HZ AT 1/10 SECONE. FREQUENCY RANGE: 10 HZ TO 60 MHZ. [65 MHZ TYPICAL] SENSITIVITY: 10 MV RMS TO 50 MHZ, 20 MV RMS TO 60 MHZ TYP. REfCALE INPUT IMPEDANCE: 1 MEGOHM AND 20 PF. [DIODE PROTECTED INPUT FOR OVER VOLTAGE PROTECTIC N.] LEAD ZERO POWER ACCURACY: + 1 PPM(! .0001 %1; AFTER CALIBRATION TYPF:AL. STABILITY: WITHIN 1 PPM PER HOUR AFTER WARM UP [.001', (TAL] IC PACKAGE COUNT: 8 [ALL SOCKETED] AID INTERNAL POWER SUPPLY: 5 V DC REGULATED. OFF INPUT POWER REQUIRED: 8 -12 VDC OR 115 VAC AT 50/60 POWER CONSUMPTION: 4 WATTS

KIT #FC -50C IS COMPLETE WITH PREDRILLED CHASSIS ALL HARDWARE AND STEP -BY -STEP INST IU :TIONS WIRED & TESTED UNITS ARE CALIBRATED AND GUARANTEED.

SEE THE WORKS Clock Kit 60 HZ. PLEXIGLAS XTAL TIME CABINETS Clear Plexiglas Stand BASE Will enable PRICING! Great for Clocks or any LED 613ig .4" digits Digital Clock Kits SPECIAL Digital project. Clear -Red 12 or 24 hr. time or Clock- Calendar PRIME - HIGH SPEED RAM Chassis serves as Bezel to .3 set switches Kits to operate 345 fie increase contrast of digital Plug transformer from 12V DC. ABINET I displays. all parts included 1 "x2 "PC Board

Power : Black, White Plexiglas is Red 5 -15V 21L02 -3 49-% 3 "H,6Y "W.5Y2 "D or (2.5 MA. TYP.) Pre -cut & drilled LOW POWER - FACTORY FRESH Clear Cover Easy 3 wire hookup II 1 -24 $1.75 ea. $1.85 ea. CABINET Kit 1850 -4 CP Accuracy: ± 2PPM 100 -199 ea 25 -99 1.60 ea. 200 -999 1.39 ea. 2 S4"H,5 "W,4 "D $6.50 Size: 6"H,41/2 "W ,3"DAssembled #TB -1 (Adjustable) RED OR GREY PLEXIGLAS FOR DIGITAL BEZELS $2995 Complete Kit $415 1000 AND OVER 81.29 ea. 0 $ '2350 21'45. 3 "x6 "x1 /8" ea IF I 9.95 JUMBO DIGIT CLOCK 1_=111=1__Ì11=1_Ì ICl R-111111- ;;I_111 li 1: l- A complete Kit (less Cabinet) fEa'' ring: six .5" digits, MM5314 IC 1:!], 1 Hr. 17111E -511002EtL ÌÌM ;- I110i\RL... 0,91T- 1' Ì time, PC Boards, Transformar, Line FOR THE BUILDER THAT WANTS THE BEST. FEATURING 12 OR 24 HOUR TIME - and all Parts. Id oal Fit 29.30 -31 DAY CALENDAR. ALARM. SNOOZE AND AUX. TIMER CIRCUITS Cord, Switches in Cabinet II Will alternate time 18 seconds) and date 12 seconds) or may be wired for time or date display only, with other functions on demand. Has built -in oscillator for battery back -up. A loud 24 hour alarm Kit #5314 -5 $1995 ,Z/'38. with a repeatable 10 minute snooze alarm, alarm set & timer set indicators. Includes 110 VAC /60Hz power pack with cord and top quality components through-ou 7 - JUMBO DIGIT ea. ' $995 CO 7W1C 4 ~ KIT r CONVERSTION .7 KIIT -70018 WITH 6 -.5" DIGITS ..639.95 DISPLAY k?1* Convert small digit LED clock to large KIT - 7001C WITH 4 - .6" DIGITS Et 6 - _ED's. 2 -.3" DIGITS FOR SECONDS ..... $42.95 .5" displays. Kit includes 6 info. KlT- 7001X WITH -.6 "DIGITS .645.95 511111O111111 Multiplex PC Board & Hook L: Kit #JD -1CC For Common CO- ode KITS ARE COMPLETE ILESSCABINET) X 7WI DISPLAY 7001 B DISPLAY Kit #JD -1CA For Common A1ole ALL 7001 KITS FIT CABINET I AND ACCEPT QUARTZ CRYSTAL TIME BASE KIT A T PRINTED CIRCUIT BOARDS for CT 7001 Kits Specify for 7001 sold separately with assembly info. PC Boards are 117031/i I ;_11 rL OI-1C drilled Fiberglass. solder plated and screened B, Cor X- 57.9!5 with component layout. Na!; ! 24 P VARIABLE REGULATED 12 AUTO BURGLAR MODEL 12 VOLT AC or 20135 1 AMP #2001 DC POWERED ALARM KIT SUPPLY KIT r0 ASSEMBLE AN0 EASr 10 INSTALL POWER LN EASr 6 JUMBO .4" RED LED'S BEHIND RED FILTER LENS WITH CHROME RILE ALARM PROVIDING MANY FEATURES NOT VARIABLE FROM to 14V ALARM HAS SET TIME FROM FRONT VIA HIDDEN SWITCHES 12/24 -Hr. TIME I ORMAT NORMALLY FOUND KEYLESS SHORT CIRCUIT PROOF PROVISION FOR POS I GROUNDING CHARCOAL GRAY CASE OF MOLDED HIGH TEMP. PLASTIC HORN 723 IC REGULATOR STYLISH SWITCHES OR SENSORS WILL PULSE TWO WIRE NO POLARITY 1100K -UP RELAY AT IHZ RATE OR DRIVE SIREN KIT 2N3055 PASS TRANSISTOR BRIDGE POWER INPUT CIRCUITRY - P ROVIDES PROGRAMMABLE TIME DELrS TO BLANK DISPLAY [Use When Key Oft in Car, LIMITING AT 1 Amp OPTIONAL CONNECTION S. PERIOD UNIT CURRENT FOR EXIT, EA TRY ALARM TOP QUALITY PC BOARDS 8 COMPONENTS INSTRUCTIONS. MOUNTS UNDER DASH - REMOTE SWITCH KIT #ALR -1 KIT IS COMPLETE INCLUDING CAN SE MOUNTED WHERE DESIRED CMOS DRILLED & SOLDER PLATED MOUNTING BRACKET INCLUDED RELIABILITY RESISTS FALSE ALARMS E 115 VAC 4 $9.95 FIBERGLASS PC BOARD AND KIT #20Cl 3 OR 250 PROVIDES FOR ULTRA DEPENDABLE ALARM $2595 Power Pack EA. DO NOT BE FOOLED BY LOW PRICES' THIS IS #ALR ALL PARTS (Less TRANS- COMPLETE KIT MORE -1WT $2795L ea. #AC -1 TOP DUALITY COMPLETE KIT WITH AL- PARTS FORMER) KIT BPS -01 $B.95 INCLUDING DETAILED DRAWINGS AND IN WIRED & OR AVAILABLE WIRED AND TRANSFORMER 24V CT will ASSEMBLED UNITS WIRED & TESTED o STRUCTIONS $3795 3 OR m TESTED TESTED provide 300MA al 12V and ORDER #2001 WT [LESS 9V. BATTERY] $3595 EA. MORE ea. n $19.95 I Amp al 5V. 53.50 Wired for 12 -Hr. Op. if not otherwise seeified m m m TO USA & CANADA ADD 5 FOR SHIPPING, OPTOELECTRONICS, INC. ORDERS 3:1 HANDLING & INSURANCE. ALL OTHERS ADD 10 %. C.64 BOX 219 HOLLYWOOD, FLA. 33022 ADDITIONAL $1.00 CHARGE FOR ORDERS UNDER IANKAMERI':ARD - COD FEE 51.00. FLA. RES. ADO 4% STATE PHONE [305] 921 -2056 / 921 -4425 TAX00 V

CIRCLE 48 ON FREE INFORMATION CARD 101

www.americanradiohistory.com BONUS SALE SMOKE & GAS ALARM With a 525 prepaid order get an inter data catalog XM -646 With a s50 prepaid order get the 8080 user manual 8K RAM BOARD IC SOCKETS REG. _-1= - FULLY ASSEMBLED & TESTED, JUST SOLDER TAIL TIN WIRE WRAP TIN (31 19.99 pm! sta. 100 pins 10 PLUG IT IN -64 21L02's (in sockets) 100 11 299 4 22 18 ALTAIR & IMSAI 8080 COMPATIBLE, 25< 14 48 40 32 - OM 14 25 22 18 16 48 43 35 Your Family BOARD REGULATORS, FULLY - Protects BUFFERED 27 23 20 24 75 70 60 24 50 45 36 From Fire & Smoke 28 80 75 68 Molex *Loud Horn Warning 40 99 94 89 50084.75 SK 038 1K 8.50 10K 70 S18995WHO NEEDS A KIT? BUY IT, PLUG, &GO 2K 16 50K 325 CARBON FILM RESISTORS VHF -AM PORTABLE High .25W 5% All STANDARD VALUES COUNTER DISPLAY KIT RO0111y module for home FROM 2.7.A. to 2.2., STOCKED Ideal built counter IN DEPTH projects. Includes 7490 decade eachh hutdrd thousand counter 3- CHANNEL RECEIVER 100 m, ni mum 7475 latch, 7447 driver, and RCA .6" 404 $1,60 Per rai' $14- NUMITRON display. PCB with plated Ihru no ml. of values RA -422 Was hole and instructions supplied in 677 Cat. RESISTOR ASSORTMENTS PERSBOARDL(EDIFROMeOrronnectsN plated) ._ 200D /IRCUI`,TOARD Hear (Hi -VHF 150 -175 MHz) 2005 ',WM5QIFORI pgr Police, Weather, Fire. Morel CP *vi/ digit $2- $2- yl *Hurry! Quantities Limited ' C' 7490 Ñn. J Ìiib , Just Install Crystals Needed -SUPER SPECIALS- 09V Battery Included 1 74S206 DIP 256.1 45NS RAM 5 .90 RESISTOR ASSORTMENT XM-677. Crystals Ea. 99C " .e ' :90 LM308AH OP-AMP ,,,Pr,,. with metal cabinet N A776 " "PROGRAMMABLE .90 PUSHBUTTON All ßu9 m CB MONITOR 78105 1092.1A + REGULATOR .30 100ea 1/4W1/4W 570 78112 " " "' 3.9 6.8 11 18 17 39 CONVERTER CHANNELS .30 ' 56 81 110 180 170 390 78L2.6 2.6V .1A positive .30 560 910 1.1K 1.8u 1.7K 3.91 AUTO RADIO WWI' 5.6K 8.M 1115 I. 171( 391 1 THRU 23 MM5369CRYSTAL OSC. TIME BASE 1.75 56K 68K 1001( 11015 18. 170* 'E. 69015 56015 67a 1.1m 1.814 1.7M MM5O581024 BIT STATIC S.R. MINI. 2.00 CB-417 LM300 ADJUSTABLE REGULATOR .60 /` 99 Q 1 ___:' $44.95 i,, 0 rw'-Tvl LM723 " .50 0 k 99 *Converts AM 747 DUAL OP -AMP 9 '50 r ) AU-580 Auto Radio to ZENER 16V 1W on tape .10 TV REPAIR INTEGRATED CIRCUITS 221-34 221-46 CB Monitor DIAC 27 VOLT TRIGGER 2.25ea. _. DIODE .2O221 -42 2218 U43089 1 Mounts In or Under Dash *For Traffic & 221 -65 221 -62 LM211i 0/ CERAMIC FILTER 10.7 Mhz. 1.25 no *Has Volume, Tone and Manual ' Road Condi- 7812 TO-3 lamp REGULATOR .69 Tuning Controls -J son Reports 78M05 T0220 .5A .69 - SWITCHES - DIP TRIMMER 0 -TRACK TAPE BATTERY TURN 1/4X1/4X1/4 RED PUSH BUTTON 12 MI, CAD RECHARGEABLE 5K or 20ÚK only 40-MINUTE BLANK N.O. MOMENTARY "AA" PEM -LITE CELL CONTACT , mfg. DALE ` Reg. 30C each $.50 FOR $4 TA -907 Ci BA -341 8 $ 2 POTTER P 11I C

100 I! 22 BRUMFIELD ,Iltil EACH actual size it. 1000 195 Type Designed for Music KHP Relay + 1 2 Volt a PDT Reproduction 3A Contacts .1 ' *Made By 3 Famous MINI MINI TOGGLE , 'Erased Never Used 24VDC Manufacturers EXTRA SMALL D. P. D.T. ,,,{{{ COIL II ÏIÑ

3A 125VAC CONTACTS h;.; 650 ohms 120VAC TI NICKEL CADMIUM each $1.50 = l . I Io.srw CASSETTES 8 - 10. ;IFtMli2i" TA -879 BATTERY actual Pkg, 75 100 - 95. size S 1.60 ea. of 3 LAS PACKS JBT MR1 -223 5 AMP DPDT 150 Mhz Prescaler ROCKER SWIARH AIEH *Standard Penlight Size PANBI. Fee your to REG. lie frequency countern ter do MOUNTING HARDWARE Rechargeable Over & Over KKK or UHF frequencies. kit ter todivide measure ths _/ input signal by ten (10 or 100 vlth 650MHz option) I 2 -"AA" Batt. Pack. 2 4 Volts RI[ contains drf !led clrcuf[ board, 1 MC IOIJI 79 ea. BA-359 , Ea. 2.00 - .. - -` -T -252T- - IC's, all parts needed and instructions. will, BA-32 Batt Pack. 3 6 Volts fen $6 150/170í91z KIT %12.95 BA -3 Ea 3.00 650MHr option W/11090 IC 529.95 v ft -requires 60- Minute 49/c supply Í 4 i i der iÌ' ÌI -"M" Ban- Pack. 4 8 volts and c arcano t pp.part .2A, or kit-- - Blank -- BA- 361.... . Ea. 4.00 T0.92 TRANSISTORS SUPER LED's 50 FIRST QSAAISY TEDSTIC family TRANSISTORS ASSORTED TYPES i 673z n Inn a s 1 i PNP, NPN, AND EVEN A FEW n [nk. 151E AeffESr J DARLINGIONS.. THESE ARE 'n be mated a p to 25A 1.0.:1 - ,, NOT U -TEST SPECIALS FROM FACTORY ' le. Bet., Auer! Ted w /order ea. REJECT BARRELS, BUT FIRST QUALITY Or i f q d v/l 1 S PARTS WITH HOUSE MLI NUMBERS. Infra Rea v/hfgh i X299 JUST 250K phd `\ AVAILABLE -SO STOCK UP 260 S. FORGE ST. NOW ... FIFTY FOR g2- DEPT. L -6 AKRON, OHIO 44327

POBOX 41 Money bock guarantee- $5 minimum order. NAME 778{t/ we pay post on orders for $10 or more. All payment must be in U.S. funds ADDRESS orders Foreign Sacramento Ca* must include post BAC & MC ore not prepaid orders and shipping is added CITY STATE ZIP 95841 916 334 2161 4811 MYRTLE AVE QM' SfK A DESCRIPTION PRICE EA TOTAL

BR B'' LD r1 BANKAMERICARO ELECTROT1ICS ',h.,7114, CIRCLE 43 ON FREE INFORMATION CARD CIRCLE 69 ON FREE INFORMATION CARD

www.americanradiohistory.com Terms : 1 prices subject to change without -t )n_CMn All All merchandise subject to prior sale' 3050 VALMONT ROAD Minimum order $5.00. Please add $1.00 postage and handling BOULDER, COLORADO 80301 Colorado residents add 3/. % state sA No COD's, please. Ph: (303) 442 -1212 Foreign Orders send U.S. Funds ON_ i GIAfT CATALOG REED RELAY DIGITAL READOUT! FA0 MOTOR LOGI-CAIE _ .3" orange and yellow readouts The best bargain on this by Monsanto. Factory prime. 11 page !!! -Our brand new Common anode. 1977 riant catalog packed Yellow (DRY -730) $1.38 with dozens and dozens of High quality, ultra -sen- Orange (ORO 730) 51.38 117VAC fan motor for super buys on electronic sitive 5VDC SPDT reed use in cooling insides of components. Contains such relay. Use in a variety of test equipment; operat- unique components as: Pneumatic switches, el- applications where tran- P.C. TRIMMER POU ing models, cooling ectric motors, Caps, wire, resistors, diodes, sistors or SCR's are not yourself off, etc. A fan- switches, LED's, transformers, transistors, and May be Universal instrument enclosure e. t a wide quite suitable. tastic buy at this price ! much, much more. Perhaps we have just the driven directly from TTL. variety of applications. Unique inter or olexi- item you've been looking for !! -Only 25 cents RRY -510 $1.50 MOT -115 442.95 glass rack assembly will hold up to 6 -1.=" by (no minimum order required), or get it FREE 4" PC boards. Great for packing a o or corn - ponents a very with any regular order of $5.00 or more 11!! into small space. ad is very I2V RELRY PRnEL LAMP professional touch to any project. tva,e from 110VAC 1/8" thick anodized, extruded alum- nun. So lamp. PART NO. PRICE panel tough that you can run over it witfo.nt cemag- 41127 OPTO IIOLRTOR TYPE lamp NPN phototrans- Neon ing it 1!1! The Logi -Case comes wth a evers- inside with istor & PN infra- r 470 ohm, vertical PCV -471 .25 ible front filter allowing you to cl co.e be- white plastic red light emitting 1K ohm, vertical PCV-102 .20 tween transparent red or smoke gaey. Now outer lens diode. 1500 volt 2.5K ohm, vertical PCV-252 .20 available in two popular sizes: isolation. 3ma toll Brand new 12VDC relay assembly.ln- 5K ohm, vertical PCV -502 .20 Small: 4GL x 3'GD x 1%H. output current. Excellent fre by Cornell- Dubilier. Has cludes drop- 10K ohm, vertical PCV -103 .25 Large: 6L x 4'' /:D x quencv response to 300 khz. N.O. and N.C. contacts. ping resistor 2H. 22K ohm, horizontal PCV-223 .25 & mtng clip S Brand new Motorola 6 pin DIP with Measures appx. 1 z 1N" 50K ohm, vertical PCV -503 .20 SMALL ILCS -11X11 T 5 full spats & data. $9 NE L-110 470K horizontal LARGE : P01 -027 1.00 10 for CRY-012 :1.50 ohm, PCV -073 .25 ILCS-2001 5 294' w. aIMI RO17O DIODE ITROBE TUBE ALARM IWITCH TRAOIFORMER HEAT IHRIAK I-3pf TRIA Much easier to use Experimenter's de- Mini transformers Mini cap. than electrical tape. trim 6nei [(, light 1 New xenon for clocks, etc.Out- The famous Motorola HEP170 Slip over solder for crystal circuits, strobe tube & trigger Includes magnet magnetic puts 8V @ 500ma universal replacement diode. joint & heat. Tube hand probes, etc. duo. transformer. Tube reed switch. Design your own or 12V @ 190ma. Rated 1000 PIV @ 2.5 Amps. will shrink to form tight seal. sures 3/16" diameter op. from 150 -300V. alarm system and save $$$. With specs. HEP -770 20 cents ea. 12-6" peices, assorted sizes. PCT -130 FFT -100 CMX -812 $150 100 for only $14.50 1.75 BAS -100 $1.95 HST -120 $1.45 95 V.O.H. LOOK MIDI -POT .Iuf.6000V CAP 203055 TOGGLE !WITCH POWER RELA# 11 1 New by IRC, PC- Heavy duty, SPST . t Potter & Brum- feild 120V. Solid state Voice Operated mount trimpot. %" H The king of audio power trans- high quality. Rated yJ SPDT, 25 Amp. ' switch. Complete w/ all parts by N" diameter. for ex- istors now at an unbeleivable 15A @ 125 VDC. 1.x New by Sprague. Great Y-012 and completely assembled. perimenting w/ high voltage. price !!! Brand new TSW -111 CR SCR output. W/ schematic. PCT 104 VOX -900 $1.50 500 AXC -160 704 BNC -055 504 954 34.00 / lnAP IWITCH RI88on CABLE WIERD lWITCH WIRE IPECIAL RUBBER FEET POT w /IWITC.H Mini SPDT 22 ga. magnet wire. Molded, adhesive back New by Allen- Cond. Part No. 1' 10' snap switch by Strange, but Unique solder -thru rubber feet in peel -off Bradley. 100K grei Cherry. Rated useful reverse- insulation. Buy by ' sheets from 3M. 0 mini 1/8" shaft, 6 RIB -006 .25 2.00 5 amps, 125- action snap switch the poung and save! /."' mount. with 12 RIB -012 .45 3.95 754 250 VAC. w/ lever. NC & NO connection (Appx. 500 feet). Round: (RRF- 120) 12 for SPST switch. 24 RIB-024 .85 7.95 -120) 12 for 55 r 1T MSW-523. 65 LSW -100 75 LBW-220 $3.95 Square: (SRF 0v R -104 65 MICRO IWITCH TTL DATA BOOK TDB -254 $4,95 VACUUM !WITCH SPST pneumatic switch. En- Miniature SPDT momen- o The newest edition of the TTL data book for design Detailed N closed diaphram activates with tary contact pushbutton. specs on over 900 TTL devices including standard and high-technologyhigh -technology vacuum or pressure. Extrem- Rated 5 amps @ 125VAC Schottky Clamped TTL. Pin assignment drawings of all TTL types. The ely sensitive Brand new. fi MSP -111 most complete book ever written on TTL. -By Texas Instruments. 95 VPS -195 $1.95

TRIMMER BOARD! 5 MEG H.V. POT! 1.5V DC MOTOR mini-/WITCH Made for test probes, these High voltage pots w/ insulated Great for -oys, experimenting, Brand new by C & K. Very high qua r-,- boards contain 2- 5 -30 pf trim- Or® shaft for protection against etc. 6" leads, 1/16" shaft. SPOT toggle, rated 5Amps @ 125 VA: capacitors, 1 -500 ohm and 1 high voltage. type. mer (N® MOT -015 504 On- Off -On 1K choc miniature trimmer pots. - ..Small (OVR -505) $1.45 MST -111 1/8" shaft 10 for only 54.00 $1.10 PAT 018 90,k 1/4" shaft/Large (TVR -505) $1.75 P.C. TRAOIFORMER PHOTOFLAIH CAP 11UMERIC BEZEL COMPUTER CAP/ moo -POT Super high quality. Brand new Rubycon. r 754 Quality computer grade caps. Input 117VAC, out- 600 uf at 360 volt. Use T 12000mf @ 25VDC pats: 5.5V @ 200ma with our flash tube & trig- CGC -122 3.95 High quality dual coed otic pot. -10.5V @ 250ma or ger transformer to make a 5900mf @ 60V DC 1/8 and 1/4 inch shafts. NwIg Allen 12V @ 300 ma. very high quality strobe r CGC -596 2.50 Bradley. Measures 5/8" gaar- Front With specifications. light Ill Black molded bezel & dig'-al dis- 5000mf @ 30VDC pot is 25K linear, rear pot is !.3K log. PCX -120 PFC -360 plays. Snaps into square hole. 2Y" CGC -503 1.95 MV R -255 1.95 long by 7/8" high. Adds a profes- 2700mf @ 25VDC $1.50 sional touch III NBZ -001 CGC -272 1.75 $1.75 CLOCK CHIP JUMBO L.E.D. POT AUTI FELT FEET .OIuf DIIC 10K POI . uf disc ceramic Most popular clock chip fiJumbo red LED for LI aDEDWITCH .01 Brand new C&i for Standard size capacitor. We have on tie market. National experimenters. Fac- Long shaft 3/8" diameter. Comes in ostat, 1/4" shef deep panel pot hex nuts- thousands 111 MM5314. 12/24 hour, 50 tory prime units. a4m peel -off strips of 15 felt standard pot. mounting. 3A 0) 2 sizes:es: Buy while they last or 60 hz, 6 digit. .200" diameter. $ feet per strip. TVR -103 125VDC. 4 3/8" PTN -380 4 DCP -010 MME -314 LED -188 5 FFT -015 strip á 9C S *4.95 for 1. SSW -221 25 1/4" PTN -140 25 5 your choice, 10K POT DIXIE BELL .O2uf DIIC 25 for 100 ITRnD -OFF CORRECTOR COMPonEnT New Allen Bradley Enclosed, alumi- .02 of disc ceramic Insulated stand off Female UHF to CARRIER We have Y," dia., BNC male connect- mini 1/8" shaft, nized signal bell. capacitor. I2AU7 TUBE terminal, Molded plaste er- %" mounting dia. 6-8VAC or 38V thousands I!! We somehow man- 5/8" long. With '/." or. Plated, new. hole drilled ñ ce. New units. Buy while they last mounting screw. ADP 239 OVF -103 DV. aged to get ahold of ter. 7/16" I0. r -020 55 SOT -210 DBL -720 $4.00 DCP $ hundreds of these. 10/$1.49 8 1.95 CLP -050 5, 25 Very popular num- ber for replacement .1 CRP CAP 8200uf CP /50V CAP ROCKER IW. BARRIER BLSK in radios, TV's, etc. 52OOuf 1800uí TRW dipped my PC mount, 2 pole New and unused. New by STM. 5200 1800 uf at 40V DC. 8200 uf at 1E t Dt:. lar capacitor. 3 position. Used, 1111 o 01e11a1®llel o AUT -127 of at 25 VDC, PC Brand new. Brand new by bla - .1 uf at 50 VDC. but in very good Black molded bakelite 504 leads PCL-184 lory. condition. PCL -522 AXC-821 DCP 150 barrier block, 5 position. 554 154 RSW -231 254- BTS -250 2554 Sur, 150V 75 o m MIDI CAP TYPE mKm 204 760 HC 60 AMP;! TERMIfAL .01uímminiCAP 47pí 5 uf, 150VDC cap. m Single solder ter Ultra miniature cer- Extremely sta- Power terminates Ultra-miniature .01 uf Great for audio COMPAR ATOR mina) strip. amic capacitor for ble me[talized LIII strip. Sells new f:- ceramic chip capacitor, ¡ crossover networks. New Fairchild type 760HC DO Bakelite mount. crystal circuits, etc. polycarbonate. voltage comparator. over $11.00. axial lead. Appx. ' /." Non -polarized. single m -010 150 VDC. lead Mfg. by Curtiss STS long. High quality. NPC -515 604 .01 uf at TTL compatible. 8 for UMC -047 104 4" lead spacing. MKM -010 PTS -060 ` DCP -015 154 TO -5 case. CMP-760 50$ S40í. J v

CIRCLE 8 ON FREE INFORMATION CARD 103

www.americanradiohistory.com computer Strobe Light Kit StrobeTube Special BRAND NEW depot inc factory prime strobe (Credit Cards Accepted) tubes. Never be- 3515 W. 70th Street, Minneapolis, MN 55435 fore available at (612) 927 -5601 such a low price. Assortment of 5 strobe tubes, Pana Vise Model #300 with 366 Jaws $21 .95 COMPLETE variable -rate strobe light kit. Contains all with schematics B &K +7)47) 30 MHZ Scope Dual Trace $765.00 parts, including line cord, PC for building List $865.00 board and instructions. Op- several strobe erates on 117 VAC. projects. E,1L Digi -Designer Kit -Design Your Own Circuits . $77.75 $7e50each 3 for 19.95 5 for only $2 _41) 2708 Eproms Prime Full Spec From Ti & Fairchild $16.95 B &K Model #1827 Frequency Counter $99.95 LASCR Solar Cell Green Neon List $120.00 Light activated Brand new Same as NE2 Albrechts Basic Guide SCR. 200PRV silicon solar but glows to the Basic Computer cell. Output Language $4,95 at .3 amps. is GREEN. Op- Extremely sen- I 5 ma @'/7 volt. erates on 120V. B sitive. 6 inch leads. &K Model #530 Semiconductor Tester . . . $275.00 List $295.00 4 for $1.00 1 ( 3 for $1.00 6 for $1.00 / OK Machine & Tool Wire Dispenser $3.45 each (Blue, Yellow, White, or Red) Calculator Unit Special !! AP Products 16 Pin IC Test Clip $4.75 Complete 4 function plus K switch Motorola DII 6800 Evaluation calculator unit less case and bat- Kit $235.00 teries. Rejected for various reasons: scratched keyboard, Osborn Vol. I Introduction to Microcomputers .. $7.50 mis- sing segment on readout, etc. B &K Model ï1077B Television Analyst $450.00 s Just the parts alone make it List $530.00 a terrific bargain. (Sorry, no choice of defect). Free TTL Catalog & More only $1.75 Remember - We Pay All Shipping Charges 10 units for only$15.00

Name Minimum order $5.00 Please include $1 for postage CHANEY Visa, MC and COD accepted. Address electronics Phone orders are welcome. P.O. BOX 27038, DENVER, CO. 80227 Ph: (303) 973 -1052 Part No Enclosed Send for our FREE GIANT CATALOG of unique items !!!! CIRCLE 32 ON FREE INFORMATION CARD CIRCLE 29 ON FREE INFORMATION CARD MINI -KITS Frequency 7 FM WIRELESS MIKE KIT Counter FM-1 $2.95 Transmit up In 300 to any FM tad. Sen.. m $79.95 KIT cry., or ceramic mks. Rum on 3lo a vome You've requested it, and now it's here! The CT -50 Fre- TONE DECODER KIT quency Counter Kit has more features than counters selling single UTILIZES NEW MOS -LSI CIRCUITRY novaFeatures 400 5 H, aD°le for twice the Measuring frequency range. voltage r59 IMt n 557 ¡C price. frequency is now as easy as Useful for touchdone decovng tom burst detection. SIS darned. and many pushing a button, the CT -50 will automatically place the SPECIFICATIONS ther FIM 7for 12bbutton tóucblonede- coding Puns on Sto 12 vv. decimal point in all modes, giving you quick, reliable read- Sensitivity: less than 25MV Complete Kit. IDI $4.95 ings. Want to use the -50 CT mobile? No problem, it runs Frequency range: 5Hz to 60MHz, typically 65MHz LED equally as well on 12 VDC as it does on 110 VAC. Want Gate time: 1 second, 1/10 second, with automatic decimal BLINKY KIT super accuracy? The CT -50 uses the popular TV color burst A great hence gm point positioning on both direct and prescale ter which enema.. freq. of 3.579545 MHz for time base. Tap off a color TV with fleshes 2 turn. LEOs Display: 8 digit red LED .4" height Use tor badges our adapter and get ultra accuracy .001 -50 w reg - ppm! The CT Accuracy: 10 ppm, .001 ppm with TV time base! lype°panel ll offers professional quality at the unheard of price of $79.95. Complet Kit. BL -1 $296 Input: BNC, 1 meg ohm direct, 50 ohm with prescale option Order yours today! Power: 110 VAC 5 watts or 12 VDC ® 1 Amp SUPER -SNOOP AMPLIFIER au., CT -50, 60MHz Counter Kit $79.95 Size: Approx. 6" x 4" x 2 ", high quality aluminum case up drop at vas afeee eaw or monno°my bebys to e general purpose CT -50WT, 60 MHz counter, wired and tested $159.95 Color burst adapter for .001 ppm accuracy available in 6 1mokas, Full 2 watts of output tu e 6 to 12 vous. ire any type of mike Papan 645 CT -600, m genitor 600 MHz prescaler option for CT -50, add $29.95 weeks. CB -1, Kit $14.95 Com42plete Kit, BN -9 $4.95 VIDEO TERMINAL MUSIC LIGHTS KIT - SIX DIGIT CAR See muss alive, 3 dike,em irynos IC h L t with music KIT $149.95 o. for tm+oepa 1, one for the 12/24 HR CLOCK 4 channel inmvmuatly ldluetmle. A compact 5 x 10 -inch PC card that requires only an ASCII key- IOW 4 runes up to 300 wnl áG et for pan.. board and a TV set to become a complete interactive terminal for band tote clubs an KIT $27.95 connection to your microprocessor asynchronous interface. Its CLOCK KIT Completc Kit. ML-I 5795 224-Hour 12 -Volt AC or SC AUTO-DIMMtP many features are single 5 -volt supply, crystal controlled sync and High Accuracy It minute/month) $2.6D baud rates (up to 9600 baud). 2 pages of 32 characters by 16 lines, Want a clock that looks good enough for your living room? SIREN KIT --1 6 limbo 4" LED readouts Forget the competitor's kludges and try one of ours1 Features, jum- read to and from memory, computer and keyboard-operated cursor Easy, no- polarity hookup -9 reno au4 o and page parity bo A" digits. Polaroid lens filter, extruded aliminum case available rune on 19 voce uses 945 ohm control, error display and control, power-on ini- Display blanks with ignitor arneroro runt :peke tialization. full 64-character ASCII display, block -type see -thru cur- In 5 colors. quality PC boards and super instructions. All parts are Case mounting bracket included Complete Kit, SM -3 $2.95 sor. Keyboard/computer control backspaces. forward spaces. line included, no extras to buy. Fully guaranteed. One to Iwo hour as- Super instructions Ca, CHH sembly time. Colors: silver. gold, black. blue and bronze (specify). Complete Kit DC -11 $2795 CODE OSCILLATOR KIT feeds, rev. line feeds, home, returns cursor. Also clears page, Powerful of apobs clears to end of line, selects page 1 or 2, reads from or to memory. gd toémrYr,ol,Sant tot w ntng The card requires 5 volts al approx. 900 ma and outputs standard Clock Kit, DC-5 $2295 vin, battery

CIRCLE 30 ON FREE INFORMATION CARD

www.americanradiohistory.com Watch for our suaermarket bargains each month! IS TH CONDENSER MIKE n u c® "TIE -PIN" TYPE k wAORGESE T It'. a little giant in sound p $ -¡ quality. Metal encased with IE POLY built -in FET circuit, o SUPERMARKET directional, freq. r p. 20- ELECTRONIC FFF 12,n00Hz, Less tie pie or DISCOUNT 7/16" X lapel clip, 600 hw - ELECT- SPECIALS pedaner. 1, 5 V DC. DEC. 1977 - RADIO 7/so long No, 12R3178 4.95 INS AMPSpIid state cilatritry. 4D "GEL -SEL" POWER PAK AM -FM -MPX TUNER MATRIX mu letas quad In 5 -12 -15 Rechargeable) Perfect for 4D Matrix for 2 8 4 speaker systems Well /Console volts! back -up power for comput- Contemporary design bl ck and chromo Iront panel tapes, and ... orde Gives alarma, and feel of a Ove s performance. 1 Sealed, spill- proof, leak- Slide controls for VOLUME, -AMP proof. Better than NI -CADS, The Philharmonic BASS, TREBLE and BAL- REGULATED recharges to 100% capon- ANCE. Selector for PHONO, je SPECIFICATIONS, AMP: FM -MPX. Jr ivy. Compact, only 4' Pwr. our SW x 2 RMS, both TAPE, AM, FM, ,. Rocker switches for POWER POWER SUPPLY 1" x 2", than into 8 ohms, 40 -20000 110WEA ea or parañk Leeds or ON /OFF. AFC, STEREO /4D New! Easy assemble! Hz. TOD 0.9%. Freq. reap. MATRIX. Also features ster- to lead/ antimony gel (sorry, 15- 20,000 ±2db. S/N ratio Uses LM340K volt - !ti eo headphone FM ster- positive oo 05db. FM: Sens 2.7 uV for lack, Re regulator. Reverse leads Your eo indicator. 6 V wch.öng),t' 6 20 db S /N. Requires 115- for a negative supply. Buy 2 choICe VAC 60 Hz, Size: 8'/z Cat. for M power supply! With 1000 MILS No. 11204088 $4.95 1344 x 31,z ". Wt. 7 lbs. í2R40000 7 $69.95 transformer. regulator, PC KIT Cop & components. 100 KHz* 000fary°;,` r101m200, "r`i;'; FACTORY OVERSTOCK Complete kí4, nothing elselee KHx Calibrate LAB -N -HOBBY TEST EQUIPMENT to buy. Wt. 4 Ills. MARKER e. e'e.ham rigs nd receiv- Transistorized cet. No. Volts 0.001%, 'size TRANSISTOR CHECKER 1] 12R3854 5 2 tor CRYSTALS í1.'zAccuracy x With i t'-' Tests NPN, PNP, Powers 0 12R3857 12 818.95 Dons for building makerr DYNAMIC SIGNAL 15 generator. 100 RHz after and unknown semi's, Simple 12R3858 to use, both in-or-out of Wt. 1 TRACER trimming. cuit. Automatically iden- Order by Cat, It's like having a third hand. tifies polarity. Tests leak- Simplifies locating circuit Bóó 25% OFF`. No. $2ys 95 age, matches similar tran- troubles in AF, RF, and IF 104.067104.092 KHe O 105.000 KHz sistors. with VOM to circuits. Easy to use, cm- 104.092 KHz E114.000 KHz testn e, dynamic leakage Bio 15% OFF teat pact and lightweight, only "ow we have and more. Built -in quick 2í.'z x 2 x 5 ". Built -in We cu ket, Requires 1'/,,,V "D" Order by Cat. No. 12R 19, and gain control. the 10 Prlces!I POLY PAKS "CHIPS" ell. Worn tructions. we h test leads. Requires 9V G5117460 .20 a, Type No 01' x 2 x 5 Wt.I 16 ass. ". rt =qy 597462 .14 4.0 AWAY IC PRICES! $12.95 507464 .14 SN74141 92, 0 Type Sala .14 0 5074145 89 Order Cat. No. 12R4048 and Type No. í2R3933Nei $14 95 No. 12R3934 O 597465 0 5074108 25 Type Sale SN]400 40.14 0 597470 .28 0 567401 ,1q 0 597471 .69 5974153 93J ICM7205 Stopwatch $14.95 51474154 99 G Ay3. 8500 -1 Six TV Games 9.95 ADAPTOR 0 597403 .14 G 597472 .28 STEREO TO QUAD 597404 .17 O 597473 .31 G SN74155 78' MM5330 41/2 oe o dos, Gives the feel 0 Digit DVM 4.95 Derives quad a od fro c of 0 5N74156 68 8038C Volt Oto 4.95 No 0 S97405 .18 0 597474 .31 Control No. stereo. Works with 1l mod- "live" performance. .19 567475 .48 G 5974157 64 KR2376 Encoder ROM BCD 6.95 Cat Inputs 2 0 597408 G .r 1283910 el, all makes, hooks up I power necessary. 0 594707 .24 D 5117476 .33 0 5N741*0 99 95H90DC 350 MHz Prescaler . 8.88 RCA plugs, outputs 4 RCA 51174111 67 x 0 S97410 .14 0 597478 .79 0 MC14410 Touch Tone Encoder .. 9.95 x 2', .19 SN74163 87 MK2002P WESTINGHOUSE 2 ". Wt. 14'ozs/ SN7411 5N7480 .33 Char. Gen. (2513 equal) 3.95 D$2.95 0 597413 .39 9 597482 .59 SN74114 95 D 72078/7208 Frequency Counter, pair 29.95 0 597414 .61 0 SN7483 .69 0 51174125 95 ICM7107 3'/o Digit DPM 12.50 ONOS e0 3 597416 .24 0 597485 .88 5974116 15 2.95 3 19 `] MM5316 Alarm Clock SN741] .24 SN7486 .29 0 5117412 SPECTROL óió :: ó =óú 2SOO 4 O 6080A Microprocessor 14.95 E9 l C H for $250 SK SN]430 .14 1] 557498 2.95 SN7417 93 1 1702A Erasable PROM 4.95 "SKINNY- TRIMS" IOK SN7423 .2 0 5N7490 .69 0 5N7411 5 69 2708 8K EPROM 22.88 squnr Screwdrit,er0112R3863 25 Turn uprlght,type 64 20K 0 SN7437 .26 O 557491 .63 O 5974177 77 2102 -1 1K RAM 1.39 shaft, 20 o tolerance. t st SON 5974179 49 t .14 597492 .45 z0,12R3864 25 Turn flat, type 64 LOOK 0 507430 0 rte Ort .trot. No. 0!12R3868 I 200K 0 5N7432 .24 SN7493 .45 SN74110 69 Singlee turn flat,trpe 63 PC 1 ads. Order Can. s II 5N741* 1 95 RCA "POCKET" VOM SN7437 24 O 597494 .69 1000 ohms per volt upnhl and ...able In all lrM. r.11abl. In Cat. No 12R2ae2 enly. 1 M.a p 5117438 .24 0 5N7495 .69 SN741*2 69 SN74110 1s Model WV-039A. Features 0 557440 .14 O 597496 .69 0 17c precision. movements 3 AMPS 5147441 .79 0 S97498 .69 511741t .99 O tape) for e 0 597442 .49 0 4574107 .29 SN741£2 83 diode protected against more! Measures DC volts decks & l Modern 557443 .61 0 SN74112 .19 597411 3 83 burnout. capeeineto 83 0 -15- 150 -1000: AC volt. $16.88 'Iv' 0 597444 .61 0 5974113 .19 5974154 DC current With on/off swswitch, x 21/a".LEI) 0 597445 .69 0 5974114 .19 597411 S 75 0 -10 -100 -1000: "cir 4 AMPS Iamb. built-in circuit 75 0 -15 Oros: resistance X1000. POWER 0 597447 .69 0 SN74121 .31 514741t , ak- Sensitivity 1000 ohms /volt 1 VAL 60 ti z, 10 SN7450 .14 0 5974123 .49 SN74If 9 69 fir Iba. C15at. No.' AC -DC. Uses penlite yell. % n " SUPPLY $19.95 12R3452 SN7451 .14 0 51174126 .39 SN742(O not included. Size 2's G 597453 .14 0 5974128 .39 SN742f1 Y .. Completely 12 VDC @ 3 Amps output 597454 .14 0 SN74132 .83 5974214 Cat. No. 1203921 wired Regulated. continuous duty 0 557455 .14 0 SN74140 1.00 51474215 +25

TEST TA! YOURSELF N S.-1l'l'! BARREL KIT #264 BRIDGES! KIT 0270 PRE- CUT'N'TIN N ED 20 for /// HOOKUP WIRE EXCLUS $1.98' =) NR, '. 200 lenaths'$1. We 2 10 note. 2 bot 2 tons df '4, Breadboardera nil 25 amp full GUARANTEED into 4" to 8" not n nM precut How good. d.v't / v1n lengths. Asst. for plastic know. Untested and to .by. ass. jackets. Wt, 12 200 Wt. 9 ozs. ft. approx. No. 12R 3959 No. 12 441 22 BARREL KIT #20 BARREL KIT #253 BARREL KIT BARREL KIT 244 KIT #239 BARREL KIT #35 TRANSISTOR#/ fìCC CALCULATORI LINE CORDS V5,, NEON LAMPS SN140 KEYBOARDS 1702A ELECTROS S for 30 for r f1.,A$1.98 ROMS 50 for $1.98 Y' $1.98 $1.98 It 'bugs" by l b.. 100's of AC power u ' ' 3 for $1.9 4 func- Famous NE-2's. All manic . For mikes, stereos; 1 -cond. tortes dump m in ear It's true! 20 -key, Heavy-duty. 6 -ft. long. s 18s Hobby fallouts of the &- .Is. keyboards at ridicu- nut factory made millions plus shield, 22 ge, vinyl WeW' don't wish to pa-ate tion Hoge. White vinyl insula- )-.,ur tel. moue e ble program- -away, 44t. 12 Dos 8 and boreered 'em jacket. Wt. 1 lb. wide assn voltages 8 a ,ems lous give tion & lded plug. Wt. vantage. mable ROM. 2045 bit. Cat. No. 12R3524 ze. Cat. No. 1203943 12R2613 Cet. No. 12R3729 Cat. No. 1203577 tu 100 f. 1262' 47 B ARREL KIT #225 /- B ARREL KIT #22 ARREL #205 ARREL KIT #201 BARREL KIT #210 BARREL KIT #76 BARREL KIT #161 SOUND TRIGGERS ll IC SOCKETS INI BLOCK V INDICATORS GLOWIN' PANELS 1 -WATT ZENER 400 PARTS CAPACITORS w /leads h Al 3 for c47-1.7,..-'4 3 for :;;;,.,1íi/ 7 100 for $1.98 !4 8 for I. Includes tors. rk. $1.98 SO for $1.98 15 for $1.98 $1.98 $1.98, ' Untested diodes, IC's. for Pt - h ob 1 41S J 00- m,v's. i "Hand clap" señsitizes crys- $1.98 Unbelievable: Worth $50. Test lamp manufacturer .1" x I" panelsa thët. glow Far,ortF. .; e. sorne PC board. e.I tal mike amplifier, triggers Mfr unloads! Four 1 -pin, High precision submini dumps inventory! Worth blue -green with 110VAC. N yvvr- l..-=ce -:i g a offer. 6, into barrels by I Use nice lites. indica- 12, under 100%e .. SCR. Use for alarms, to! tour 18-pin. Solder teil, t-or for ail snolIeetions. 69e ea. Like grain -o- 'heat. for 0. 10. 10,. material. tors. e c.Cat. No.12R 3550 Double p1aR 32022]41 No. Wt. 6 ozs. No. 120.3825 lo- profile. No. 12p3621 Wt. 3 yes. No. 12R3528 Cat. No. 12R3526 hobb> class. Cat. 1203401 B ARREL KIT #154 BARREL KIT #163 BARREL KIT #138 BARREL KIT #128 BARREL KIT #162 BARREL KIT #160 BARREL KIT 7 y -WATT METAL PANEL SWITCHES MIN1-DIP IC'S a fil FILM JUMBO RED LEDS MINI TRIM POTS VOLTAGE AXIAL ELECTROS REGULATORS 30 for .100 150 for 15 for $1.98 30 for I no. for $1.98 40 100% m erial. user can - 10 for $1.98 $1.98 9 nos. 741'.. LM380, 703. 505, fore= $1.98 cellation a` from factory $1.98 L5í -309K TO -3 barreled, II d you hear of OAK" An- 555. who knower Factory $1.98 values 100 to 1 melt hot by w'ho'other test. Untested dumps, 3V 10 mils, For At the pound, but egpt maker barrelled mixed. you Asst, capoUt co d 100% metal film resis- 100's of p ^ojects, red lens. What a buy. Single turn. wants to check 'em? Your all types of rotaries, elec. d hobby. Wt. 1 lb. voltages. Cat, No. 12 43127 tors. Long leads. 1203413 Cat. No ^1203369 t µ. Wt. 6 0 . .12113345 Rain. Wt. 20 ozs. 12R3330 'trio, slides. etc. 12R3288 Cat No. -12R3245 BARREL KIT #9:: BARREL KIT #126 BARREL KIT #115 BARREL KIT #109 KIT #104 BARREL KIT #101 B ARREL KIT ¡!N TERMINAL STRIPS SLIDE VOLUME RESISTOR SPECIAL PHOTO ELECTRIC lV'o HALF WAITERS 4 UPRIGHT ELECTROS MOLEX 100 70 0- 0óo SOCKETS CONTROLS CELLS 40 for goodn^(l00 for $1.98 200 for i_.- 200 for $1,93 - 10 for $1.98 Resistor factory t -ier 150 for Cet.NO Wide asst. of terminal strip 10 for $1.98 to all ,. from I contact Asst. GE types, CDS types, mixingin 11.10olor $1.98 12R13144 Includes: 1. lof to 300mf in mixture 81.93 Strip manufacturers $1.98 1 /e. 1/4. 1/2. 2- Mixed by factory. Big job `out -coded resist ors in dump! We wattere, carbon. 8 o s. for us of voltages. t n07, marked Calculator maker barrel dump is your gain. Cat. No. 12R3057 to separate. 100% barrel. But value it dare. gut a zillion of 'em. 100% good..12R3054 good. Cat.No.12R3052 3R3046 Votes no n good. 12113226- Wt. 1 lb. Cat.No 12R3136 9 es.4 BARREL KIT #83 /.!. B ARREL KÌT #41 BARREL KIT :SO BARREL KIT :875 BARREL KIT #86'.1 BARREL KIT #71 BARREL KIT #68 CAPS NAT. IC BONANZA! 4OBBY LEDS / LM -340T VOLTAGE' SPECIAI WATTERS POLYSTYRENE SLIDE SWITCH([ c' REGULATORS CAPACITOR 100 for $1.98 40 for $1.9$ pcs. for ._ 100 for 30 for $1.98' Hobby and untested, factory 15 for $1.98 100 100 shapes. sizes. WOW! Top U.S.A. maker 100% $1a98m All mixed i barrels. Linzers, finector rejects, hobby, good. Finest cabs te. As a gam- momentariea. et, 700.s. nROMS. DTL'S. tea dumps discretes in barrels. tic rejects May lude $1.98 - Suppliers 'em inm the ble e bought 10 values: zwus shop pak for .. Hobby and tested. Use- , micas, m ldeds, plastics, throw istero. clock and calculator TO. 25, 18 mixed values: itchina projects, chips and more Wt. ors. able yield 50% or better! volts,' TO -220 power tab. ceramics, discs, etc. Nifty barrel. It's a li'I gold mine. from factCat 12 All markedtat.No, all Cet.No.22R2726100 4F good Cat. No. 12R.2860 Wt. 4 o,s, Cat. No. 1202859 R'[. 4 rtes. Cat.12R2835 100 %good Cat.NO12R2738 1202735 Hood..Catlio.12R2729 BARREL KIT #31 BARREL KIT 035 BARREL KIT #27 BARREL KIT 028 BARREL KIT #20 BARREL KIT #14 ., BARREL KIT #39 METALLIC DIPPED MYLAR.14 HOBBY NPN PO PREFORMED PREFORMED DISCS PLASTIC TRANSISTORS LONG LEAD DISCS RESISTORS RESISTORS i. 100 for. TRANSISTORS 100 for $1.98 /1 50 for 100 for 60 for $1.98 Made ko 200 for 1.98 $1.98 Finest capacitors .tr 15 for $1.98 mostly Corne g rte got hUrr, :_ nil $1.98 Untested and hobby transis- $1.98 fallouts and the d`. mfr's shelf inventory shiny finish. Imagir e Factory "off finest resistor tt10s0 for pt tors. TO -92 (TO -18), asst. Auct ton al Prime. TO -3 powers. 100 % ett 1 % but he dumped 'em i bor.- ro dumping 'em in ta e1,. spec" Mostly' 100: 2N numbers, asst. manufac- marked only. Long leads hobby, no opens. no shorts. 5% toi. & er barrel of refs. Preformed, for PC use, Cat. Cat.N412R259710(% good a No.1202608 100% (good values too!,12Ltjß0ti turers. Wt. 8 oz .í12R2604 12R2598 100% gout Wt. 1 Ib. Cat No. 5,02617 Values. Cat. No. 1203809 Mixed L m B ARREL KIT #7 BARREL KIT Terms: Add postage Rated: net 30 n B ARREL KIT #1 BARREL KIT F 3 mot- SALE. - m PRECISION VOLUME SN7400 DIP C'S Phone : Wakefield, Mass. (617) 245-3829 1 94148' 914 for FREE RESISTORS CONTROL G á. 75 for $1.98 Retail: 16 -18 Del Carmine St.. Wakefield. Send VV SWITCHING DIODES m 30 for Marked 14 ana 16 pin dOlO. SPRING CATALoa 200 for 100 for $1.98 Y 0 list ant flap, m $1.98 lowJgood Cou raters, M Al $1.98 Single,, variety of bals, diodeseat these prices! whoh. knows? s. 11214 POLY PAKS Marked and unmarked 1/ hilt ' values, styles. - Cat.No.13R2418 Untested. by. Wt. 14 nos. r12ß2415 BË PHO Ei] 1 /2. 2 watte,Ne12R0428 small ones. Cat. 1 2421 P.O. BOX 9421R LYNNFIELD, MA. 01940 tD V ©Poly Paks Inc`!' Wakefield, Mass., U.S.A. 1977 MINIMUM ORDER - 28.00 CIRCLE 21 ON FREE INFORMATION CARD 105

www.americanradiohistory.com BUGBOOK® W9600651 eN II 517.80 Mr lel 7400N TTL b P44w II. Aa., WI A. llr, LaINTJ HOBBY -WRAP TOOL -BW -630 IrF,r,,, Continuing Education Series I Mid ö, M SIM two boW wAOM AM W mmrwnb nsrP4d 7lan 'TM need 1rt (1 roer dl M wa m mow nora 771. l4yc m4c 7.a mm in mn- SN7100N .16 wm mlcrowmeor e3knw Yn'1 Icon 4e of 59747214 39 SN74160N 1.25 MKMn 0M basic concept C) d19ntl wCmwn uldNlq . Battery Operated (Size 5974019 .18 5N747314 39 1c. NP4be. NkJlw. bum demoer, 11 Avn..nunpMM11,1E0 dNtoA. RANb, RON4, and mum. muon mon 51474029 10 5974749 35 59741629 1.a5 . Weighs ONLY 11 Ounces 59740314 20 597475N' 50 59741839 99 1100006Ib 58.00 Wraps 30 AWG Wire onto 5974049 20 514747883 15 514741649 90 Iw 191M n. nMg, om41. lar, RUM Standard DIP Sockets (.025 inch) S9740514 10 5974799 5.00 5974165N 99 $34.95 1M Rama W immaua you to IM Npwnu, ART tlg Munponam 5974019 35 SN7480N 50 59741869 1.25 -o 7crlTl 11401 alowed. with bit and sleeve M.Mw 4. tomato u a6 put mnmrmPnln ano 04414 Complete built-in SN74079 35 0474829 19 5N71167N 3.25 RbemP. MC inter. sbMam 441404111mmown090 5974088 20 5974839 .70 SN74170N 2.10 Iw n 597409N .25 09748514 69 5871172N 6.00 THE 556 119888 APPUCATRINd 94.95 W 00006 III 116.Of 5874109 .20 SM486N 39 5N74173N 1.50 WIRE -WRAP KIT WK -2 -W 60URCE6006 9/3H EIPENMENT6 A PY n. Itq7. owM 9. lar, eWTJ. J10r10 A 114M - 5971119 30 S974889 3.50 597417414 1 25 M 114w1 aaea . Mn 14 Ro OAbk 4M 4m n 6IO9Nr. Pastas Marra mati vI!4 too WRAP STRIP UNWRAP S974129 35 5474859 51474175145 99 7 b boo sMws you 2.49 Oat IM 5551mwr e and Mw to usa n IrcJWed,re ow tnara m mnmMA w 4841 n mow 0ngeaJ anlera me IMn1M115 Acton Tool S87413N .99 5974909 45 5X7117681 79 *mom, mnpM m crate ruCyM 4' IMO e.n An M wn anal Imlmnm yo4 to Pe MwK m rel0otd44/1 for 30 AWG Wire 9eMml.Us mar 5974149 70 5974914 75 597417714 .79 w wnrolunus11pm. union 5 IAda10 mom e b rm... nul 7m IOw Ow brA- o n m Roll Ft. AWG m NOM a00.0041. mrany u6 140 Mond on IM 805800651 It 11 EelwM 4mr0u9 1021151.1000012 11 of 50 White or Blue 30 Woe 0471104 35 5974929 49 SN74179N 2.49 Amateur P6 S9741714 35 5971939 .49 59741609 99 00008 Vi 110.0089881 . 50 pcs. each 1 ". 2 ", 3" 6 4" lengths - INSTRUCTOR'! MANUAL 63.00 5971209 20 5474949 79 597418114 2.49 M o.1 t lar. P4. A. A.r, Jw A. l4w 1Kwcabr A0104bo o 8uWbok I n II MIMI wrasbons reymu19 pre-stripped wire. 39 597416214 m 514742194 5974959 79 15 oueors,447M M Fannm.m A19n1 w.ctm.n. mew m4m0mpwr 4791140.19 and SN7422N 49 59749851 .79 SN7419N 1.95 ÉaM wdmmA wm cM 4WnqrMM1MmM 80004 mlcmmmwgr enatlg M 1nN11m appro. m M+iMrvmO 41. and 60204 mbrt6g2wgm7mMq $11.95 5974239 17 SN7/97N 3.00 5874113514 1.95 OP AMP MANUAL 59.10 MOM moms m9mmm o pbon V Im0 a d S14742511 .29 59741009 125 587/1858 15.00 m M 9169 0 MOM. M MOO. 1mn004 Por 25 mn. 00004 791emmn9 and n MAI MAIM S974269 29 59741079 19 597418714 600 on n nMw n 04 Am4M. manb C1.mr non Mn e WIRE WRAP TOOL WSU -30 5974279 .37 5N74109N .95 59741889 3.95 DWG 55.54 C5108 -M - DESIGNERS PRIMER 54.00 WRAP STRIP UNWRAP.$5.95 5N7129N 42 09741169 1.95 04741909 1.79 A 6Á9D1006 I mm kgm.w 6egp1. mom for MAIM. ON a0cO and storing NO 09743011 .25 94741219 39 SN741918 1.25 nambh *ma 4m9m1 Stone at emu structure of C5105 aMae 8mu9n ww9nlcn 041151 WIRE WRAP WIRE 30 AWG 51474329 .25 59741229 .39 94741029 89 - 0974379 .35 59741239 .50 5N74193N .89 COMPLETE MANUAL FOR DIGITAL CLOCKS by John Well and John Brooks 25ft. min. $1.25 50Ií. $1.95 100ií.$2.95 10005. $15.00 5474389 15 54741259 .60 597/1949 1.25 Familiarizes techniaan of h005yis1 watt basic theories Se9nd digital cocks Includes trouble snootinO guides. basic SPECIFY White COLOR - - Yellow - Red - Green - Blue - Black 5974399 25 SN74126N 60 SN74198N 75 charactanst6 of docks, soldering techniques, clock component data sheets and construction tips. $3.95 5914409 .21 59741329 1.25 5117419614 1.00 WIRE DISPENSER WO -30 5974419 .89 SN74136N .95 59741979 1.00 - 125" Pa. 90" dia 39744261 .69 59741419 1.15 SN71196N 1.75 41111- 50 fl. roll 30 AWG KYNAR wire wrap wire 6C209 Rid SIf1 %CIII Red 1011 $3.45 59744315 .75 S9741129 2.95 5974196,4 1.75 ea. XC209 Green 431 Green 4 /51 Cuts wire to desired length SN7444M 75 94711439 3.25 047420014 559 XC209 Orange 431 ,«;;1 Yellow 431 Strips 1" of insulation Specify Blue -Yellow- SN744514 .75 SN74251N DISCRETE LEDS - White -Red SN741449 3.00 1.79 XC209 YNIOw 4181 %011 Grange 431 0974469 .89 597414514 1.15 59742799 .90 .280° W .185° dia. .006° dla. REPLACEMENT DISPENSER SPOOLS FOR WD 30 0474479 .89 04741479 2 35 59742839 2.25 XC22 Rid 5851 X0526 Re 531 8C556 Rid 531 MV50 - Red 631 59741944 .89 59741189 2.00 5X7428181 6.00 Specify blue, yellow, white or red $1.99 /spool XC22 Green 431 XC526 Green 4/11 60556 Green 431 5874501 .25 S8741501 1.25 59742859 8.00 XC22 1'Nlow 431 X0526 Yellow 431 00556 Yellow 4/51 INFRA -RED LED 59715141 .25 597415114 .79 04743859 75 DIP /IC INSERTION TOOL WITH PIN STRAIGHTEN 6C22 Orange 431 %0526 Clear 431 6C556 ornge 4/51 v. 51'16 5971539 .25 5N74153N .89 59743669 .75 SOL-22 RI 431 CC556 Clear 731 Flal 531 M Inserts both 14 and 16 pin packages. Pin Straightener 5974544 .25 58474154N 115 545743674 .75 51474591 25 S974155N 19 SN713549 75 built into Handle. 0974609 .25 S14741589 .89 SN74390N 225 DISPLAY LEDS Model INS-1416 53.49/ea. 5147470N .45 59741579 .89 91743939 225 TYPE POUNTY M PRICE TYPE POLARITY 9T RINCE 20% Discourt for 100 Combined 741306 HP 5082 -7400 SERIES MULTI -DIGIT MAN 1 Common Anode -led .270 2.95 MAN 6630 Common Mode -mantle .560 1 25 - MAN 2 5 5 7 Dot Maim-red .300 4.95 MAN 6640 Common CaNmderorange-0.0 .580 1.25 10 or more MAN 3 Common Cathode -red 125 39 MAN 6650 Common Cattoneroran9e 111 .580 1.25 CMOS 'W' ht. Common Cathode Red 2 Digit S .79 .69 034000 23 MC14562 1450 MAN 4 Common Cathode-led .187 1.95 MAN 004044 89 6660 Common Anoderonnge .560 1.25 C01001 .23 MAN 3 -5 volts (d 5 mils /second 3 Digit .89 .79 cD4566 2.25 7 Common Anode-ad 270 1 25 MAN 6680 Common Cathode -o9s$o .560 1.25 C 04046 1.79 C04002 23 MC14583 3.50 MAN 76 Common Anode -glean 270 195 MAN 6710 Common Anode - 7 segment Monolithic 4 Digit .99 .89 C04047 2.50 red -0,D. .560 1.25 CD1006 1 19 MAN 7Y Common Mode- yellow 270 1.95 MAN 6730 Common red -DM. .560 C0048 1.35 Mode- 125 Dip Package 5 Digit 1.19 .99 C01007 25 74068 Wes MAN 52 Common Mode -green .300 1.00 MAN 6740 Common Olhode rid -0.D. .580 1.25 C009 49 C01009 .49 r4000 39 MAN 71 Common Anode -rid 300 1.25 MAN 8750 Common Cathode-red 111 .560 1.25 C04050 49 C04010 19 74CÁ2 55 MAN 72 Common Anode-red 300 1.25 MAN 6760 Common Mode -rid .580 1.25 C04051 1.19 TV GAME CHIP SET $9.95 CD4011 23 74C04 .75 MAN 74 Common Cathode-rid 300 1.50 MAN 6780 Common Cathode -rid .560 1.25 - C04053 1.19 CD4012 25 74C10 65 MAN 81 Common Anode-yellow 300 1.00 51701 Common Includes AY -3- 8500 -1 Chip and 2.010 mhz crystal C04056 1.49 Mode-red 51 .300 1.00 C04013 .39 71014 300 MAN 82 Common Anode- yellow 300 1.00 oL702 Common Cathode -rid 1.25 CD1059 9.95 300 (2.010 crystal $1.95 ea /AY- 3- 8500 -1 Chip $8.95 ea.) 1 - - C04014 39 74020 65 MAN 84 Common Cathode- yellow 300 100 01704 1.19 Common C401X5.led .300 1.50 CA4015 1 19 74030 .65 UM 3620 Common Moderoange .300 1.00 DL707 Common Mode-red .300 CD4D66 1.50 ZENERS DIODES RECTIFIERS CD/016 449 74092 MAN 3630 Common Anode-orange _1 - 2.15 300 1.35 01741 Anode - Common -red .600 1.95 C04068 39 TYPE BOLTE W PRICE TYPE Ban W PRICE cD4017 1.19 MAN 74C73 1.50 3640 Common Ca5Mde-oange 300 1.75 01746 Common Node -re 01 630 1 95 C01069 45 9746 3 3 4001nm 4/1 90 144005 800 PIV 1 MAP 10 /1.00 CD4o18 .99 74074 1.15 MAN 4810 Common Anode-orange 300 100 0L747 Common Mode -red .600 225 CÁ4070 .55 N7515 5.1 400111 414 00 1144006 600 PIV 1 AMP 10/1.00 CDN19 49 74089 4.00 MAN 4640 Common Cathode- orange 400 1.00 0L749 Common Cathode -sen .630 1.95 704071 23 Il 4752 5.6 4000 4/1 00 1144007 1000 PIV 1 AMP 10/1.00 CD1020 1.19 74C90 3.00 MAN 4710 Common Mode -rid 01 400 1.00 0L750 Common Cathode .600 CD4072 49 -IN 249 9753 6.2 40314 4/1.00 19360 50 211014 8/1.00 CD1021 1.39 74093 2.00 MAN 4730 Common Anode .400 1.00 C04076 1.39 -rid DUN Common Cathode -red .110 .69 9754 68 400m 4/1.00 194148 75 10e 157.00 C04022 1.19 74295 MAN 4740 COMMA Cathode F9070 CD4081 23 200 -M .400 1.00 Common Cathode (195359) .250 .75 N959 8.2 400m 8/1.0 1144154 35 IOm 12/1.00 cD1023 23 710107 1.25 MAN 4810 Common Mo0e-ye5ow 400 1.00 F90503 16105901 C040e2 .23 Common Cathode .500 1.29 119658 15 400m 4/1 00 194305 75 250 20/1.01 C04024 79 74C151 MAN 6610 Common C01098 2.49 2.90 Mode-orange- 580 1.25 F140507 Common Mode 11140510) .500 1.29 95232 5.8 500m 28 194734 5.6 lw 28 C0025 23 710154 3.00 MC14409 1495 N5234 62 500m 28 184735 6.2 1w 28 04028 2.25 74C157 MC14410 14.95 2.15 145235 6.8 500m 28 1144736 18 lw 28 C01027 69 740160 RCA LINEAR OR- 220609 Kit $19.95 XR- 2206KÁ Kit $14.95 MC14419 4.95 125 N5236 7.5 500m 28 194738 8.2 1w 28 CC04 89 710161 3.25 CA3013 2.15 CÁ3052 0.Og WAVEFORM TIMERS MC14506 75 9456 25 400 6/1.00 194742 12 tw 28 1.19 710163 CA3023 2.56 CA3083 1.80 .49 MC14507 99 100 5155 61458 150 7th 6/1.00 194744 15 1w 28 C01030 49 74C164 3.25 CA3035 2.45 093086 .85 562054ERATORS 56. 40 XR -32099 C0450B 395 EXAR 444854 180 1014 6/1.110 191183 50 PN 35 AMP 1 60 C04035 .99 74C173 2.60 CA3039 1.35 C730119 3.75 XR2206CP 5.50 XR -556CP 165 391510 139 144001 50 PIV 1 AMP 12/1.00 191184 100 PIV 35 AMP 1.70 CD4040 1.19 74C193 215 CÁ3046 160 CA3091 150 XR2207CP 3 85 MISCELLANEOUS 5R- 2556CP 3 20 C04511 1.29 844002 100 PIV 1 AMP 12/1 00 1811185 150 PIV 35 AMP 1.50 C04041 1.25 74C195 175 CÁ3053 1,50 CA3102 2.95 09221 ICP 56 70 59-224005 4.B0 C04515 2.95 944003 200 PW 1 AMP 12/110 1141186 200 FN 35 MAP 1.80 CD1012 99 á0C95 1.50 CA3059 3.25 CA3123 2.15 STEREO 0&OD045 XR -4136 200 PRASE LOCKED LOOPS C04518 1 29 834004 400 PP/ 1 AMP 12/1.54 191188 400 Pw 35 AMF 3.00 CD403 80097 1.50 CA3060 3 25 Cl3130 1.39 XR- 1310CP 53 20 061468 3.85 %R -210 5 20 C0520 129 CA3140 1.25 CÁ3080 .85 119 -13199 3 20 60-1488 5 80 69.215 6 60 SCR AND FW BRIDGE RECTIFIERS CA30B1 2.00 5R -1800P 3.20 9R-1489 4 80 58.567CP 1 95 kM3U0N so 1247399 1.19 15A SCR LINEAR CA3fi001 1 75 C360 @ 400V 01 95 90 -2567 2 99 592208 5 20 69.567CT 1 70 1M301H 35 LM3403-8 1.25 LM71101 15 C38M 354 @ 2030 SCR 1 95 LA1301CX 35 LM340-12 1.25 IM741CN 35 IC SOLOERTAIL LOW PROFILE (TIN) SOCKETS 252328 1.6A @ 200V SCR 50 LM302H 75 .39 - 4M3401-15 1.25 L15741-149 12A 124 25.49 50 100 1.24 RIDA 981 W 50V FW BRIDGE BEC. 1 95 1M30H 1.00 1M3407-18 1.25 16174714 .79 25.49 50100 B pan 16 Eí7 15 24 MOO 9803 12A @ 200V FW BRIDGE REC 1 05 LM305H 80 1.25 LM74714 79 mn 535 37 36 L5001-24 1/ pm 19 20 15 26 an LM307CN 35 LM7J8H 39 p 38 44 43 m e0 W 1M350N 1.00 16 NI pin 22 21 20 36 xx11W tomW LM308H 1.00 LM351CN .65 LM718N 39 pan 60 59 58 TRANSISTORS 18 pin 29 28 27 40 pm LM308CN 1.00 78MG 175 1M13034 .90 63 62 fil 22 pan 37 36 35 LM309H 1.10 LM370N 1.15 LM139N 1.19 SOLOERTAIL STANDARD (TIN) 14 pin 5 27 25 LA4309K 1.25 161373N 125 1413059 1.40 24 28 Dm E 99 90 81 16 30 pan 27 25 1 1 11A3103N 1.15 LM377N 4.00 1M150715 .85 36 pin 39 26 1 15 18 pin 35 32 LM311H 50 LM3809 1.25 1M13109 2.95 30 40 pin 1 59 145 170 LM311N .90 1M380C9 LM1351N 1.85 24 54114 45 45 42 .99 SOLDERTAIL STANDARD (GOLD) LM317K 650 LM381N 1.79 LM1114N 1.75 8 in f 35 32 24 pin LM313CM 1.50 11438215 1.79 LM1458CN .59 24 S 70 63 57 14 mn 35 32 29 26 LM319N 1.30 NE501K 8.00 LM14969 95 pm 1 10 1 00 90 16 pre 58 35 72 LM3206-5 1.35 965105 600 1.151556V 1.75 MI 36 pm 1 75 140 126 18 pin 52 47 43 40 1 PONS 141 m LM3201I-5.2 1.35 NE529A 4452111N 1.95 pm 75 1 59 1 45 4.96 MOM Nam 3644 Im W 1,35 NE53114 14290114 2.95 WIRE LM32011-12 3,00 WRAP SOCKETS (GOLD) LEVEL #3 2141015 L11. 20 3a116l 1/01 00 LM320K-15 1.35 NE5361 6.00 1A13053 1.50 6 In 8.10 JB 35 22 plc .96 85 75 2.011 3m c11rI5CR 2411 W AAM SI LM320T-5 1.25 NE540L LM306514 69 41 rN14 ml W 6.00 10 pm 45 z4 pm E 1 05 95 85 e4w P.u6 W 10 11 i5 LM320T-5.2 1.25 9E5509 LM3900N(3401) 49 m 110 14 pin 39 38 3' 20 pn 1 40 1 25 10 LM32m-8 7.25 9E5550 L61390514 69 41 55 39 16 pin 43 42 36 pain 1 59 130 LM3909 1.25 CAPACITOR 80 BOLT CEMMC CORNER 1.25 NE5606 1 LM320T-12 5.00 18 pin 75 68 62 40 pm 75 55 I 40 IIM0 CAPACITORS LM320i.15 1.25 9E5618 5.00 LM5556N 1.85 1 -9 10.49 50 -100 1 -9 10-49 LM320T-18 1.25 NE52B 5.00 MC5558V 1.00 50 PCS. RESISTOR 50.100 ASSORTMENTS PER ASST. 10 pl 05 64 .03 0010F 15 .04 035 LM320T-24 1.25 9E565H 1 75 U575259 60 $1.75 10 OHM 12 OHM 15 22 pi 05 04 03 .0047µF OS LA4323K-5 5.95 NE5659 1.25 11/753114 .75 OHM IB OHM 22 OHM 0 035 1 5 47 21 55 0 03 .0155F CA 14 035 LM324N 1.80 NE566CN 1.75 80389 4 95 ASST. ea. 27 OHM 03 OHM 39 OHM 47 OHM 55 OHM 1/4 WAR 5% = 50 PCS. UA75450 49 100 pl 05 .04 03 .022µf .06 65 0 LM339N 19 NE567H 1.95 68 OHM 82 OHM 100 OHM 120 OHM 150 OHM 220 PI 05 04 03 04701 06 54 .04 LM340K-5 1.35 955670 1449 7545104 35 2 5 480 - ASST. et OHM 220 OHM 270 OHM 330 OHM 390 OHM 1/1 Waif 5% 50 PCS 470 51 05 04 635 .1µF .12 09 075 1M310(.6 1.35 111703CN 45 75/52CN 39 100 VOLT 11mÁe FILM CAPACITORS LM340Kd 1.35 LM709H .29 7545304 .39 470 OHM 560 OHM 680 OHM 820 OHM IK -_ 00101 .12 .10 17 .02201 13 11 OB LM340(-12 1.35 LM709N .29 795404 39 ASST. 3 5 ee. 1 25 156 186 2 2K 2 76 104 WATT 5% 50 PCS. .0022 .12 10 67 .04701 .21 17 13 LM340(-15 1.35 LM710N .79 75491CN 19 3.34 47K 394 566 68K .004701 12 .10 .07 101 27 23 17 LM300K-18 1.35 IM711N 39 75492C9 .89 ASST. 4 5 ea. 8.26 10K 126 15K ISK 1/4 WATT 5% = 50 PCS. 01111 .12 10 .07 .2201 .33 27 22 1M310(-21 1.35 LM723H 55 75494CN 85 4-14% DIPPED TAMTALUMB (SOLIDI CAPACITORS LIA340T-5 1.25 LM723N 51 110194 5 95 22K 276 335 396 41I5 .1/35V 28 23 17 1.5/350 30 26 21 LA100T$ 1.25 LM733N 100 574195 3.25 ASST. 5 5 ea. 565 bail 82K 101K 1206 1/4 WATT 5% 50 PCS. .15/359 28 23 17 2.2/25V 31 27 22 150K INK 2205 2101 3308 .22/359 28 23 17 3.3/25V 31 .27 22 741500 ASST. 6 5 ea. 3906 470K 5600 6805 820K 1/4 WATT 5% - 50 PCB .33/359 28 23 17 4.7/259 32 28 .23 741502 74LS00 T T L ;" 47/350 28 23 17 6.8/250 36 .31 25 /;, IM 1 2M 1 5M 18M 2 2M 741103 .29 741575 .69 7115180 1.95 .fib /35V 28 23 17 10/250 40 35 .29 ASST. 7 5 ea. 2.74 3 3M 3 9M 4 7M 5 6M 1/4 WATT 5% 50PCS 741504 .35 741_576 .49 7119161 1.95 11/350 28 23 17 15/250 63 50 40 08NM1URE 741505 .35 741583 1.75 1 ALUMINUM ELECTROLYTIC CAPACITORS 7415162 95 ASST. 8R Includes Resistor Assortments 1 -7 (350 PCS.) $9.95 ea. 741508 29 741585 249 7415183 1.95 Aalal Lad RNMI LN .47/50V .15 13 10 .47/250 15 741510 .29 741586 49 741510 I 13 .10 95 $5.00 Minimum 006.. - U.S. Pends Only Spec noels - 258 - Send 35e Stamp lW 1070 Catalog 1.0/000 .16 .14 .11 .47/500 .16 14 .11 741513 .69 741590 .89 7411175 1.95 Calllmil. linnets Add 0% pies Tu Dealer Ildormatlon - Ayell.Ole 15 741514 1.75 711592 .89 7415181 3.69 3.3/500 .13 .10 1.0/180 .15 .13 .10 741520 .29 741393 .89 7415190 2 49 1.7/250 18 14 .12 1.0/255 16 14 .11 741528 39 711595 1.50 7415191 2.49 10/250 .15 .13 .10 1.0/505 16 .14 .11 10/504 .18 .14 12 1.7/180 15 13 .10 741527 39 711596 1.89 7115192 2.19 1978 741528 .39 7115107 .59 7115193 2 49 22/359 17 15 12 4.7/250 15 13 .10 741530 7115109 22/505 .24 .20 .18 4.7/50/ .16 .14 11 .29 .59 7115194 1 89 CATALOG 741532 39 7115112 .59 7115195 1.89 47/250 19 17 .15 10/160 14 .12 .09 47/50V 25 21 19 10/25V .15 .13 741540 .39 7115123 1.25 7415253 1 75 NOW 741542 100/250 24 20 18 10/500 16 .14 .12 1.25 7115132 1.25 7415257 1 75 ames AVAILABLE 100305 .35 30 28 47/500 24 .21 .19 741.547 1.25 7115136 .59 7415260 55 ELECTRONICS 741551 .29 7115138 1.25 7115279 79 220 /25V 12 28 25 100/16V 19 15 14 1021 -A 74L555 .29 7415139 125 7415367 99 HOWARD AVE., SAN CARLOS, CA. 94070 220/50 45 41 38 100/250 .24 20 ` 741574 49 7111151 125 4713/250 33 19 27 100/505 35 .30 7415368 99 PHONE ORDERS WELCOME - (415) 592 -8097 741574 .49 7415153 125 7115670 3.95 10005180 .55 50 45 220/180 23 17 Ato Advertised Pelea Good mesa December 2200/161r .70 .82 55 470/259 31 28 Lì

CIRCLE 16 ON FREE INFORMATION CARD

www.americanradiohistory.com 'CRYSTALS- `` - MICROPROCESSOR COMPONENTS p Timeband THESE FREQUENCIES ONLY 8080A CPU $16.00 COP1802 CPU $19.95 PedÑ Frequency Cate /Style Pelai 8212 8 Bit Input/Output 4 95 MC6800 8 Bit MPU 24.95 CV/A 1 000 MHz HC33'U $5 95 8214 Priority Interrupt Control 15.95 MC6820 Periph. Interlace Adapter 15.00 Digital Alarm Clocks CV2A 2.000 MHz HC33 U $5 95 e 6.00 8216 BI- Directional Bus Driver 6 95 MC6810AP1 128 8 Static RAM 2ahour alarm 01 HC33 /U 95] ICY2 2.010 MHz 51 8224 Clock Generator /Driver 9.95 MC6630L8 1024 e 8 Bit ROM 15.00 ooze Burson CV3A 4.000 MHz HC18.0 $4 95 8228 System Controller Bus Driver .10.95 Z80 CPU 29.95 1007, Solid Stale CV7A 5.000 MHz HC18 U 04 95 PAM S Large Red Led Display 10' t 10.000 MHz HCtO.0 ' 256 a 1 Star" $ 49 CV12A 54 95 CPU S 8 Ognl 14 HC18U 2'.01 256.4 Stau- 5 95 CV14A 31818 MHz 54 95 8080a Super 8008 16.00 . AM 'PM Indicator 2102 024 x 941H e "D Featured on February's Front Cover of Popular Electronics Size: 20"W 151/4 Model 8388 $149.95 Logic Analyzer Kit Model 100A Model 10 HEAT SINKS fa 0 Model 100A 111 to DIGITAL STOPWA1CII 205 -CB 680 -.75A Bright 6 Digit LED Dnyay $229.00 /kit Times to 59 minutes 59 59 seconds 205 -CB Beryllium Copper w -black finish for TO -5 S .25 a Crystal Controlled Time ease e Three Stopwatches o One 291 -.36H Aluminum for TO -220 Transistors 6 Analyzes any type of digital system Times Single Event - SWt 6 Twin Checks data rates in excess of 8 Regulators S .26 See 4. s' 5215 s 90 NMpuncesi million words Pet second e Uses 3 Pemne Cells 680 -.754 Black Anodized Aluminum for TO -3 $1.66 applications Trouble shoot TTL CMOs DTL RTL Dude 4 Black Anodized Aluminum - predrilled meTroubleshooting microprocessor Kit - $39.95 and MOS families - mounting holes for TO -3 43/4 o 1V. x 2" $1.75 address, instruction, and data flow Assembled $49.95 - Displays 16 logic states up to 8 digits wide - Examine contents of ROMS See ones and zeros displayed on your Heavy Duty Carry Case $5.95 Tracing operation of control logic DIP SWITCHES SPST Slide AO64M CRT. octal or hexadecimal format #206 -4 ( 8 dip) 4 switch unit Checking counter and shift Stop Watch Chip Only (7205) $19.95 pin 51.75 a. e Tests circuits under actual operating #206.7 7 register operation (14 pin dip) switch unit $1.95 ea. conditions Monitoring I/O sequences #206 -8 (16 pin dip) 8 switch unit 52.25 tie. Easy to assemble comes with step -by -step construction - - Verifying proper system operations 31/2DIGI1' [IPM KIT manual which includes 80 pages on logic analyzer operation. - Etching Kits (cannot he shipped we din during testing 32 X A-1 P C Etch Materials MI $29.95 ea. PARATRONICS TRIGGER EXPANDER - Model 10 enough tor 5 circuit hoards Adds 16 additional bits. Provides digital delay and qualification of input clock Model 10 - $229.00 27 X A Etched Circuit Nit S 9.95 ea. -1- and 24 -bit trigger word. - Connects direct to Model 100A for integrated unit). beautsM - $996 Plugboards Complete kit - only add wale, 6 5 X 4 5 x 1.16 Epoxy glass S 6.95 ea. 3662 31/2DIplt Portable OMM GOOD P-Panern -44 P C Tabsswad 156 :4KPRfC[S7oN 22/44 Mating connector for pwgoard - S 2.95 ea. Overload Protected 100 MHz 8 -Digit Counter 22 pin double eadoue 3 nigh LED Display 20 H7-100 MHO Range . Four power sauces. Benery or AC operation Fc 6800V Unbersal Microcomputer!Prpassor $19.95 ea. 6' LEO Display barrenes. 110 or 2201/ volt New Bipolar Unit Auto ,.rity Auto Zetomg plugboard- bossy Glass - complete Crystaleenlrolled1me545e charger 12V with auto Auto Zeroing Low ' >er tmv. toc, 0 1 ohm resolution with heatsink and mounting hardware Fully Automatic lighter adager and extema Singh Unit Ylemt Oyerange reading Portable compieteiy 7 . .5" LED 5 313 x 10 X t16 copper glad - 210V power supply to meg input Impenaena sad- contained MAX -100 $134.95 Model KB500 DPM Kit $49.00 1/16 VECTOR BOARD DC Accuracy lo. typical Sue -1.75'x738" Ranger DC Voltage .n -10004 5.63. P Pattern Price Model 311D-5C-5V Po Ater Kit $17.50 - - - 0.1 Hole Spacing AC Voltage 0.1000V No L W 1 -9 10 up 9r9rgi Pan Freq Response. 50 -400 HZ PHENOLIC 64P44 062XXXP 4.50 6.50 172 1.54 410 DC /AC Current 0 -100018 JE7(0 CLOCK 169044 oe xueP 4.50 17 00 3.69 332 Resistance 0 -10 meg ohm The JE I(1,0 is. i.+ st drgdataoto our EPDXY 64P44 06249E 4 50 6.50 2.07 1.86 41:-. Sue 6 at. xaa-a2- very 5gs Wa s unit The unit lea GLASS 84P44 06249E 4.50 8.50 2.56 2.31 Accessories: tues a simm the ealnut case wife na 169P44 082WE 4.50 17.00 5.04 453 Model 2800 rrensions II Nils; es a ACCESSORIES FOR MAX 100: 169P84 082WE 8.50 17.00 923 8.26 AC Adapter BC -28 8.00 MAN72mmi ss eauoui and toe. $99.95 Mobile Charger Eliminator EPDXY GLASS 169P44 062WEC1 a. 50 1790 6.80 6 12 Rechargeable MM5314 riur - Come wan lest use from Moeel 100 Cla 5395 CLAD power car battery - COPPER BP -26 cads s operatmg manna Batteries 20.00 Charger /Ellminetor TOOL and spare tuse Carrying Case LC -28 6.00 use 1IC V AC Model 100 GAI 59.95 KIT ONLY / SLIT -N -WRAP WIRE WRAP - 115 VAC $115.95 Slits and opens insulation exposing PROFS CLIPS These joysticks feature four { bare wire CONTINENTAL SPECIALTIES 100K potentiometers, that JOYSTICK No pre-cutting or pre- stripping. Other CS Prole Boards $4.50 PROTO BOARD 6 14 PIN vary resistance proportional Comes complete with two - 100 ft spools #28 AWG wire - 4 5 x 6 19.95 S15.95 PB100 S 16 PIN 4.75 to the angle of the stick. Study Model P180 $24.50 (6" long X 4 Wide, P8101 - 5.8" e 4.5" 29.95 24 PIN 8.50 metal construction with PB102 - 7" e 4.5" 39.95 40 PIN 13.75 plastic components only at HEXADECIMAL the movable joint. Perfect PB103 - 9" e 6" 59.95 ENCODER 19 -KEY PAD DESIGN MATES for electronic games and PB104 - 9.5" x 8" 79.95 DWI - Circuit Designer instrumentation. I PB203 - 9.75 x 6th x 23/4 80.00 150K $5.95 ABCDEF $69.95 PB203A - 9.75 o 61/2 e 2 129.95 OM2 - Function Generator 5K $4.95 Shift Key finaudes °Owe, supply) $74.95 2 Optional Keys INSTRUMENT /CLOCK .43E MONITOR DM3 - RC Bridge $10.95 each for DTL or CMOS Devices $84.95 $74.95 Infection molded unit Complete OT typa //holes pdce with red bezel. 414' x 4" x 1- 9/161 , OT PROTO STRIPS OT-595 590 12.50 63 KEY KEYBOARD OT59B bus amp 250 $29.95 OT .47S 470 10 00 $3.95 ea. 111111 OT 180 OT.a7B bus strip 2 25 This keybo ro features 53 unen- 01.355 350 8 50 coded SPUl Mys. unattached to " OT 5913 --- - ' 01358 bus strip W n,y k nd el A very Wind PCB 12S 0 OT 47s 01-18s 180 5 molded x 4 IV plastic 13 base Imem. 0T-t25 120 3 75 sue most app, cations OT-BS 80 3 25 e a< OT 478 OT-85 JE803 PROBE H00195 Encoder Chip (encodes 16 Keys) S7.Ì6 n. 01.75 TO 3 00 Ay- 6.7771 Encoder Chip encodes 88 Keys) 814.96 99. The Logic Probe is a and wroth is forms most part OT 755 Experimenter 300 S 9.95 indmpens,0le an trouble mooting logic landes OT 7S TOOLS Experimentor 600 $10.95 TTl OTL RTL CMOS it derives the pewee r1 `^y!rIr-a .iti needs 10 operate directly pif of the oeturl under A97MS Diagonal Cutter - 4 semi -flush cut $7.95 ea. - a 10 mot max Ruses a MANS Funds Only SON Shoats 25e Selo 35e for lest drawing scam 7 55.00 Minimum Order U.S. - SUM tut Glalop 1 Pliers - long 50 ea - At DM5 -Chain Nose 43- readout to any of the lollongws states by Tex o California Residents - Add 6% Sales Disler Informetlon Available 1ILOWI The T -6 Wire Stripper - #16 to #26 gauge 3 75 ea these symbols IHI ofPUL5E1 Ts m - 45 1978 Probe an detect he frequency pulses to MHz $9,9\I Per Kit - to gauge 250ea 55B Wire Stripper #t0 #20 I am levers - it can pe used NOS or coded damage m CS -8 Cutter -Crimper Tool - 81/4" long 7.95 ea. CATALOG - " " " °' °" printed circuit board Ribbing Tool Cuts, Trims or Notches Metal NOW - co up to #18 gauge 6,95 ea. ames PL 5V 1A Supply AVAILABLE m this,s a standard nu power s .00 4serg de weil known Nibbling Tool Replacement Punch 3 75 ea ELECTRONICS LM309K regulator IC to provide sa. - AMP of current at 5 33 1021 -A HOWARD AVE.. SAN CARLOS, CA. 94070 yobs We try to make things are st you by peowdsre PERMACELO P -29 PLUS Electrical Tape - All Weather menehmg you need in one pack Ve

CIRCLE 17 ON FREE INFORMATION CARD 107

www.americanradiohistory.com CMOS CMOS CMOS TEXAS INSTRUMENTS TTL PLASTIC DUAL-IN-UNE I.C. CD4000BE .13 CD4052BE 1.15 74C14/400I4PC .75 LC. SOCKETS SN7400N .12 SN7453N 14 SN74132N .69 SN74186N 7.50 CD4001BE .16 CD40538E .89 14C85/40085PC 1.20 (Low Profile Solder Tail) SN7401N .14 CD4002BE SN7454N 14 SN74136N .59 SN74S188AN 1.85 .16 CD40558E 1.29 80C97/40091PC .65 Unit SN7402N .14 SN7460N .14 SN74141N .88 SN74190N 1.04 CD4006BE .99 CD40608E .99 80C98/40098PC .65 Description Price SN7403N .14 SN7470N .26 SN74142N 3.70 SN74191N 1.04 CD4007BE .16 CD40668E .59 74C160/40160PC 1.50 8 Pin DIL (C840802) .15 SN7404N .17 SN7472N .25 SN74143N 3.98 SN74192N 84 CD40088E .80 CD40688E .24 74C161/40161PC 1.50 14 Pin OIL (C841402) .18 SN7405N .17 SN7473N .29 SN74144N 3.98 SN74193N .84 CD40098E .37 CD40698E .24 74C162/40162PC 1.50 16 Pin DIL (C841602) .l9 SN7406N .25 SN7474N .28 SN74145N .69 SN74194N .89 CD4010BE .37 CD40708E .24 14C163/40163PC 1.50 18 Pin DIL (C841802) .29 SN7407N .25 SN7475N .46 SN74147N 1.58 SN74195N .54 20 Pin CD40IIBE .16 CD4071BE .24 74C114/40174PC 1.40 DIL (C842002) .35 SN7408N .17 SN7476N .30 SN74148N 1.19 SN74196N .87 CD4012BE 22 Pin DIL (C842202) .34 SN7409N .17 SN7480N .16 Cl/40728E 29 74C175/40175PC 1.40 35 SN74150N .94 SN74197N .73 24 Pin DIL (C842402) .34 SN7410N CD40138E .29 CD40738E .29 74C192/40192PC 1.50 .14 SN7481AN .95 SN74151N .61 SN74198N 1.64 28 Pin DIL (C842802) .45 SN7411N .20 CD4014BE .74 CD4015BE .29 74C193/40193PC 1.50 SN7482N .55 SN74152N 3.45 SN74199N 1.64 40 Pin DIL (C844002) .65 SN7412N .21 SN7483AN .65 SN74153N .61 SN74221N 1.14 CD4015BE .74 CD4076BE .98 74C194/40194PC 1.40 SN7413N .39 SN7484AN 1.50 SN74154N .95 SN74246N 1.95 CD4016BE .29 CD4018BE .24 74C195/40195PC 1.40 SN7414N .62 SN7485N .84 SN74155N .70 SN74247N 1.70 CD4011BE .19 CD4081BE 24 VOLTAGE REGULATORS SN7416N .24 SN7486N .30 SN74156N .64 SN74248N 1.75 CD4018BE .79 CD40828E .29 SG3501AT 3.60 ±5V Dual Tracking Regulator SN7417N .29 SN7489N 1.85 SN74157N .59 SN74249N 1.75 CD4019BE 38 CD4085BE .75 SG35241 7.25 Switching Regulator Converter SN7420N .14 SN7490AN .43 SN74159N 2.50 SN74251N 1.05 CD40208E .84 CD4086BE .75 SG4501T 1.80 ±154 Dual Tracking Regulator SN7421N .20 SN7491AN .59 SN74160N 85 SN74259N 1.35 CD402lBE .89 CD4502BE 1.15 RC4I94TK 3.95 Variable Dual Tracking Regulator ±350 ±9.50 SN7422N .20 SN7492AN .44 SN74161N .85 SN74265N .85 CD4022BE .89 CD4507BE .39 RC4I95T 2.35 Fixed ±154 Dual Tracking Regulator TO5 SN7423N .25 SN7493AN .44 SN74162N .85 SN74273N 1.35 CD4023BE .16 CD45IOBE 1.05 RC4195TK 3.15 Fixed ±150 Dual Tracking Regulator T066 SN7425N .25 SN7494N .69 SN74163N .85 SN74276N .75 CD4024BE .67 CD4511BE 18H05IIC 6.35 5 Amp 5 Volt Positive Regulator T03 SN7426N .22 SN7495AN .67 SN74164N .98 SN74278N 1.99 1.25 CD40258E .16 7800 Series .99 Positive Voltage Regulators (Plastic) 1 amp SN7427N .25 SN7496N .65 SN74165N .97 SN74279N .57 CD4512BE .69 T0-220 / LM340T 5, 6, 8, 12, 15, 18, 24 Volts SN7428N .28 SN7497N 2.50 SN74166N 1.09 SN74283N 1.39 CD4026BE 1.39 CD4514BE 2.50 78M00 Series 1.39 Positive Voltage Regulator 1/2 Amp SN7430N .14 SN74100N .97 SN74167N 2.75 SN74284N 4.50 CD4027BE .38 CD4515BE 2.50 10.5 / LM340H 5, 6, 8, 12, 15. 18, 24 Volts SN7432N .23 SN74104N .42 SN74170N 1.69 SN74285N 4.50 CD4028BE .74 CD45168E .84 7800 Series 1.49 Positive Voltage Regulator 1 Amp SN7433N .30 SN74I05N .42 SN74172N 8.75 SN74290N .85 CD4029BE .78 CD4518BE .84 T0-3 / LM340K 5, 6, 8. 12, 15, 18, 24 Volts SN7437N .21 SN74107N .28 SN74173N 1.24 SN74293N .83 CD40308E .37 C04519BE .79 78L00 AWC Series .29 Positive Voltage Regulator 100 MA SN7438N .21 SN74109N .47 SN74174N .94 SN74298N 1.64 CD4033BE 1.60 CD4520BE .79 T092 2.6, 5, 6.2, 8.2, 12, 15 Volts SN7440N .14 SN74110N .52 SN74175N .84 SN74351N 1.92 C040348E 2.95 CD45228E 1.98 7900 Series 1.25 Negative Voltage Regulator I Amp SN7442N .37 SN74111N .69 SN74176N .77 SN74365N .65 CD4035BE 98 CD45268E 1.50 T0 -220 / LM320T 5, 6, 8, 12. 15, 18, 24 Volts SN7443N .68 SN74116N 1.50 SN74177N .76 SN74366N .65 CD4040BE .99 CD45218E 1.50 79M00 Series 1.35 Negative Voltage Regulator 1/2 Amp SN7444N .85 SN74120N 1.40 SN74178N 1.19 SN74367N .65 C04041BE .67 CD4528BE 1.20 TO-5 / LM320H 5, 6, 8, 12, 15. 20, 24 Volts SN7445N .65 SN74121N .34 SN74179N 1.49 SN74368N .65 CD4042BE .58 7900 Series 1.75 Negative Voltage Regulator 1 Amp SN7446AN .70 SN74122N .38 SN74180N .67 SN74376N .75 CD45318E 1.25 T03 / LM320K 5. 6. 8, 12, 15, 18, 24 Volts SN7447AN .59 SN74123N 48 SN74181N 1.94 SN74390N 1.40 CD40438E .45 CD4539BE 1.20 78MGT2C 1.20 Dual In Line Adjustable 4 Terminal SN7448N .69 SN74125N .40 SN74182N .59 SN74393N 1.40 CD4044BE .45 CD4555BE 75 Positive Voltage Regulator SN7450N .14 SN74126N .40 SN74184N 1.75 SN74426N .45 CD4046BE 2.45 CD4556BE 75 79MGT2C 1.20 Dual In Line Adjustable 4 Terminal SN7451N .14 SN74128N 59 SN74185AN 1.74 SN74490N 1.90 CD4047BE 2.45 CD4581BE 2.25 Negative Voltage Regulator CD40498E 34 CD4582BE .95 78GU1 10.220 1.45 1 Amp Adjustable Positive Voltage Regulator CD40508E 34 CD4585BE 1.80 79GUI 10-220 1.25 1 Amp Adjustable Negative Voltage Regulator CD40518E .89 78GKC 10.3 1.80 1 Amp Adjustable Positive Voltage Regulator

79GKC T0-3 2.10 1 Amp Adjustable Negative Voltage Regulator

Our new comprehensive 1978 Catalogue, listing complete descriptions, il- Electronic Saks lustrations and special P.O. BOX 1035 FRAMINGHAM, MASSACHUSETTS 01701 monolithic pricing on over Telephone Orders 8 Enquiries (617) 879-0077 New Catalogue available on request 5647 Ferrier M. 44 Feeken Dr 10,000 items, is now avail- IN CANADA -Unit 25 MINIMUM ORDER 210.00 * ADD $1.00 TO COVER Montreal, Quebec Roadsle, Ontario 2 POSTAGE & HANDLING * Canadian customers add 30% able on request. Locations Tel. (514) 736-8429 Tel. (416) 677-4267 for duty and handling All federal and provincial taxes extra

CIRCLE 67 ON FREE INFORMATION CARD

IC or FET's WITH $5 & $10 ORDERS.t 311P. DATA SHEETS WITH MANY ITEMS. c , FREE KIT $1195 DIODES TRANSISTORS TRANSISTORS TRANSISTORS LINEAR IC's ASSEMBLED 24705 $014 j $17.95 RECT FIERS í 092 505/1 2X56/0 231 LM40T3 5 °í 2S ADVA I1M66 4a r' re nen0 244311 3/5I CP643 MO LM3/ne n 1.20 ADD $1.25 FOR 114859 fit' 25915 3101 254122 3/fl cresol 6690 10340212 1.20 +.,... 15453 re 241613 30.29 254124 6/05 CP651 MOO 611 LM340T15 1.20 15485 .29 244248 fi/f1 E100 411 L613407.24 1.20 14146 w 2X1890 .36 24458 sis, :101 1 /51 .50 POSTAGE /HANDLING 41112x7711 LM31oN 1X918 242719 .24 244254 5 /SI `102 3/51 LM317N 2.60

14962 15/$1 202228 .24 254204 111 E15 311 00555V 2 /29 14962 to 202222 5/81 254302 $0.29 MPF104 to. NE555V 2/n 149)4 011 2022124 5 /f1 244301 .29 MPF184 715 NE556A 30.90

V El 001 VARIABLE 114003 1231 242905 t0 $0/24 24492 $0 0 91002 5

8 /fl Includes All Components except Case and Meters Mv1520to flf1 2X390610 2 458 3038 LM308N II R645840N 255 MV1664 243919 5590 255484 3/81 1M3094 .94 55555V 95 MV1665 to 243822 5.01 245486 211 1483114 .90 55558V .50 s2 53.00 OTHER ADVA KITS: MORE SPECIALS: Mvno to 2X3958 1.15 255544 .50 1.013200-12 135 8030 DIP' 3.75 MV2205 fl 243970 1.00 245561 12.00 L03201515 1.35 0M75492 90 RC4195DN '16V a SOvrA VOLTAGE REGULATOR I Very easy to use. Makes a neat Highly LOGIC PROBE KIT -use w n CMOS. ))1. orl RT 1, r HAIL are most rhos net. Regulated C15V Supply for OP AMP's, etc. protection Requires only unregulated DC 118 2 Ludr'm against polarity reversal and overvoltage. Draws only a few mA from circuit -3OV) and bypass capacitors. under n4. Dui LED re,eom. Complete kit Includes case and clip leads. ONLY Szes With Data Sheet and Schematics. 8 -pin mDIP $1.25 Quad *SUPER SPECIALS: FIXED REGULATED POWER SUPPLY KITS- Snortsircuit p r RC4136 741 Low -Noise Op Amp mDIP $0,95 limiting_ Compact slat LM1304 FM Multiples and typ,ul regulation of 0.5% make these idea! for most electronic Stereo Demodulator DIP 0.99 1N34 Germanium Diode 10/$1 FSA2501M Diode Array 2/$1 plena. Available for 5V 4 500mA. 6V @ 500mA, 0V 500mA, LM2111 FM 0 12V @ 400mÁ. 15V O IF Subsystem IIF Amp, Det., Limiter) DIP 0.99 1N914 100V /10mA Diode 20/$1 MPF102 200MHz RF Amp 3/$1 1 300mA. Specify voltage when ordering. 1N6263 Hot Carrier Diode @ 3695... 0.4V 1mA O.rns DO -35 1.00 1N4001 50V /1A Rectifier 15/$1 40673 MOSFET RF Amp $1.75 U_ ZENERS- Specify Voltage 3.3, 3.9, 4.3, Thew easy- m-assemble Y. include all components, complete detail. instructions and Hated 5.1, 6.8, 8.2 400n,W 4/$1.00 1X4154 30v 1X914 25/$1 LM324 Quad 741 Op Amp .94 10, tiber9lass Pe borer. Power supply 9.1, 12, 15, 16, 18, 20, 22, 24, 27, or 33V 1-10%1 1 Watt 3/51.00 z kits do not include case or meta. Ara `1,25 per kit for BR1 50V YVA. Bridge Roc 4/$1 LM376 Pos Volt Reg inDIP .55 postage and 2X2222 NPN Transistor NE555 Timer mDIP O " °." "0 MONEY -BACK GUARANTEE 6/$1 38 Q 2X2907 PNP Transistor 6/$1 LM7232-37V Reg DIP 3/$1 ALL TESTED AND 2N3055 Power Sim, 10A $0.75 LM741 Comp Op Amp mDIP 6/$1 F IMAM SOW FREE DATA SHEETS supplier with many items from this ad. TREE ON GUARANTEED 2N3904 NPN Amp /Ste U REQUEST -741 Op Amp with every order of S5 or more -749 Dual OP Amp or two 5100 3100 e/$1 LM 7458 Dual 741 mDIP 3/51 LU F ET'3 with wary order of $ID on more, postmarkea pion 12.31/77 One foes hem pen order. 2N3906 PNP Amp /Ste 17100 8 /$1 5 Trans Array DIP .62 J ORDER TODAY-All items subject to prior sale and pricestomes subject to Wange without notice. CP650 Power FET hAmp $5 RCA29 Pwr Xistar lA 30W .70 IL Air ere new surplus ports -l00% wnmonauv testae. WRITE sTOR FREE CATALOG =)] oller,ng over too amicdnductors canned in stack RF391 RF Power Amp Transistor 10-25W @ 3 -30MHe TO -3 $5.00 ELECTE C T R O N I C S o Send 132 sterna 555X Timer 1yz -1hr Different pinout from 555 (w /datal 3/$1 TERMS: Sena ADVA check or money order IU S. funds) with order. Add 596 postage for U. S.. BOX 4181 EN, WOODSIDE, CA 94062 RC4194TK Duel Tracking Regulator !0.2 to 30V @ 200mA TO-66 $2.50 o Canada and Mexico. 51.00 handling charge on orders under 510. Calif. residents ace 696 sales RC4195TK Dual Tracking Regulator 515V @ 100mA ITO-66) 52.25 eeF 9,r de " add 10% postage. COD orders -add $1.00 service charge °e Tel. (415) 851 -0455 8038 Waveform Generator'` - Fl A Wave With Circuits &Data $3.75 108 CIRCLE 41 ON FREE INFORMATION CARD

www.americanradiohistory.com INTERN: \TION; \I. ELECTROINICS UNLIMITED FULL SPEIE 3 F7EOM DISCOUNT ON ALL 2708 ELECTRONIC DOOR CHIME KIT Sl 4.95 IC'S AND LED'S 6 DIGIT CLO'[yHIP 10% OFF ON 525.00 ;; TI TMS 1000 WITH 5314 52.95 15% OFF ON $50.00 MICROPROCESSOR CHIP 256 PROM PROGRAMMED TO PLAY c EIT nL 82S23 1'2'95 7400 .13 7451 .17 74153 Al ,'' 24 DIFFERENT TUNES v 7401 .16 7451 .17 71151 1.20 - 7402 .15 7454 .17 74155 .97 '?- 7403 .15 7460 .17 74156 .97 ' 2513 CH64 Rif 1 $E $C,: 7404 .16 7464 .35 74157 .99 INTERNATIONAL FLAVOR - PLAYS NATIONAL ANTHOMS OF U.S., BRITAIN. .35 1ó.95 7405 .19 7465 74IS8 1.79 FRANCE AND WEST GERMANY PLUS OTHER FOLK TUNES, CLASSICAL AND .30 7106 .20 7170 74160I 1.91 TRADITIONAL 5 00445 I K RAM 7407 .2e 7472 .30 74161 .7 MELODIES. 74011 .18 7473 .35 74162 1.19 * WITH ALL PARTS INCLUDING PC BOARD, SPEAKER, CASE AND 2102 31.29 .28 SUPPLIED 7409 .19 7474 74161 1.09 " COMPLETE INSTRUCTION MANUAL WITH FULL CIRCUIT DETAILS. -' 7410 .16 7475 09 74164 ,99 AL'S 0134 7411 .25 7476 .30 74165 .99 * USES 29v TRANSISTOR BATTERIES (NOT SUPPLIED). 7413 .43 7481 .0 74166 1.25 * LOW POWER CONSUMPTION. UART 36.95 7414 .35 7485 .40 74170 2.10 * 7116 7486 .40 71171 INTERNAL SELECTION OF TUNE, VOLUME, TEMPO AND TIMING .35 1.19 256 i RAM 7417 .35 2.15 74174 1.23 *PROGRAMMED 7 C 7111 ^STATE 7420 .16 74% .43 74175 .97 MATHEMATICALLY TO PLAY IN PERFECT PITCH / 45200 .75 7422 .70 7491 74176 .85 13.25 7121 .29 7191 .40 741-1 .84 PERMANENTLY.. 7425 .27 7493 .4e 74180 .90 r ATTRACTIVE CASE, CONVENIENT WALL MOUNT. 1 1 7416 .26 7494 .7B 74181 2.45 LD11O, LD111 $23.95 7427 .29 7195 .79 74182 .79 SHIPPING $1.00 31/2 DIGIT A/D CONVERTIR AT' 7430 .20 74% -79 74184 1.90 $39.50 7431 .13 74100 .% 74185 2.10 PROCESSING 7437 .25 74105 .M 74187 5755. CENTRAL UNIT 7437 .25 74107 .37 74190 1.15 RESISTOR KIT 7440 .15 74111 .38 74191 1.25 8008 PRECISION $16.95 _' 7441 .89 74122 .38 74192 .95 METALR FILM, 1 %B, RN60 _ 7441 .59 74123 .6S 74191 .85 8080A IC TEMP COEF ppm 7443 .73 74115 .54 74194 1.25 SOCKETS - Sold., TRII - low 7444 .73 74126 .58 74195 .74 profll V4 WATT, COLOR BANDED 14 pin 41 7445 .73 74112 .89 74416 1.25 8 P1^ S 17 14 Pm 59 .20 P1" . 7446 .81 74141 1.04 74197 .73 2e 60 values, 2 resistors each $24.95 69 7447 .79 74145 1.04 74198 1.73 16 P,^ 22 40 P1" 18 supplied in a 15 drawer, 7418 .79 74150 .97 74199 1.69 11111 19 i SHIPPING CHARGE 52.80 7450 .17 74151 .79 74200 5.45 60 compartment cabinet SPECIAL DEVICES LOW POWER 371 AF -IF Strop Detector DIP L93 RESISTOR ASSORTMENT 12251 74190 546 AM Radio Receiver Sub.Ynem _75 74104 .29 74161 .29 i.40 DIP 1310 FM Stereo Demodulator DIP 190 VALUE 74101 .29 74155 .29 74191 i.20 2 RESISTORS PER 74107 14% Balanced Modulator- Demodulator 99 .23 74171 .29 74191 1.50 44..2 80.6K 1440 Slerto multlpkxer DIP 246 10.5 100 499 1.65K 4.53K 7.50K 13.0K 22.1K [ 74104 .19 74172 .IS .'1195 1.50 ULN22N FM Gain Bock 34db 1.18 20.0 130 604 2.00K 5.11K 8.45K 14.0K 24.9K 48.18. 90.9K 74106 .19 74171 .56 74198 2.15 (HP) mow ULN2204 PM Gain Block 48db mDIP 1.35 100K 74110 .29 74174 .56 '41164 225 (typ) 30.1 162 750 2.49K 5.49K 9.09K 15.0K 27.4K 52.2K Generator (14x11.5 DIP-24 10.18 7I110 .29 74(78 .75 741165 zw 2513 eMr.rt, 49.9 200 1.0K 3.01K 6.04K 10.0K 16.2K 30.1K 57..K 147K 3746 Tonnes° Array DIP-14 .n lax .29 73155 1.09 60,4 301 1.21K 3.48K 6.49K 11.0K 17.8K 34.0K 63.4K 210K 73152 1.39 74156 es LINEAR CIRCUITS 76.8 402 1.40K 4.02K 6.98K 12.1k 20.0K 40.2k 69.1K 464K LOW POWERSCHOTTKV 100 s -I 171 L41 -n 62 FILM RESISTORS 1% 741500 .36 741.512 .18 741595 109 101 METAL 19 176 , 7I) M PROM 74LS02 741540 102 2K ERAS 44 COEF ± 50 ALL .36 .45 741 5107 59 í1 180 110 719 1.0' 1 702A CRA RN60 TEMP 741504 741542 1.40 104 ,36 7415164 220 80 18008 115 741 II $4.75 STANDARD DECADE V k EVES FROM 741544 .38 301 71 741.574 .59 741.5191 120 71 181 175 747 TOg64KOHM 741510 .w 741590 1.30 7415197 1ì I07 16 10.504440 PRICE 71LSID -76 71159) 1.10 108 89 CALC. CHIP 5 FUNCT QTY PRICE PRICE 1 2 95 1458 61 1 8 M WIMUM 100 1094 I.IS EACH MINIMUMI .40 Ió00 1.18 38 WITH MEMORY L95 110 1.07 5738 PF. VALUE Vi II VALUE HIGHSPEED 9 1900 44 744000 74H12 .25 741161 .25 111 95 5 555 45 7524 71 0 - 10 1.20 .25 114 1 II Z 71H01 25 74H 10 .25 744462 5%4 1.19 7525 40 10- 100 .20 5.19 74I174 .39 lì1 119 741400 .25 74H40 .25 560 119 8038 4.15 100 1000 .1C S.09 1ì1t 119 744000 .25 741150 .25 7414101 .51 561 3.19 88M 2.25 1000. IC .08 744 74HI0 ,25 74H52 .25 74H102 .58 I -0 565 1.111 75150 175 .40 124 151 566 75451 - 74H11 .25 74H51 .25 74H101 IS I., - 119 CARBON FILM REEI' TORS 5 %9 74H28 .25 744455 .25 74H106 .72 158 567 1.95 75451 50 - 1409 ., .. 7711Y, .25 741460 .15 74H108 .72 169 709 26 75453 35 .. 1/4W - ALL STANDARD V la...ES FROM 1401 1 -44 710 IS 75491 71 IC SRD9OARD S 16 IC,. with OHMS TO 5.6M OHMS 172 1.91 711 Ib 75491 .80 Accommodates pin rddNV.ul .56 CMOs . 1m,,á°"^`1'" hole` Phe^oIk .4h.M, V2W ALL STANDARD V LL :.ES FROM 40004 ,n 40174 I. w a066Á .a9 Putt copper circuit. 2 ""sn6'' .6 via" 45.80 «. 40014 .25 40104 1.72 40684 .W 1 OHM TO ISM OHMS 40024 .15 40210 1.18 40694 .W DISCRETE LED's FMH SHIFT REGISTERS EACH QTY. PRICE PRICE 40064 1.35 4022A .94 4071A .M MEI INFRARED WARFAR DOME 10 .29 2502 15124 bit MUTT DYN lb pm S2.95 (each) "inlmum 40074 .26 40214 .25 40.2A .35 l'O 2304 1024 bit MLA T DYN 8 pin 2.95 'ter value) 40044 1.52 4024A .89 4071A .09 91111011 (LIAR DOMI 110" 23 60094 .57 40254 .25 40.54 .39 2511 Tri -St4te Midi 50- 100.200 hit 0-10 3.10 ea 40104 ,54 40170 .59 40784 .79 111V5O (LIAR - AOIAL 09" .12 STATIC 14 Din 2.97 10100 5.10 ea $.05 ea 40114 .29 40144 .98 401114 .JS MYfO RFD -Á11A1 09" ,12 2518 He. 32 -bit STATIC lb pin 2c95 100 -1000 $.04 ea 40124 .25 40100 .44 45184 1-S6 2-.09 Her 40 -bit STATIC 1b pin 2.955 4459100 RID w" .12 40114 .45 40150 1.27 45284 1.56 2527 Dual 256 bit STATIC 8 pin 2.95 M CAPACITOR' 40114 1.27 40400 1.39 45854 RL209 RID DILE. SUBMINIA IURI -11" .12 I. lO 2512 Quad bit STATIC 16 pin 3.95 Solid dlpp4ld +20% 40154 1.27 40424 1.47 RLT -TI -03 WHITE DUE. SUBMINIATURE I 1024 8 5 10l bit accom. Dynamic pin 1.7 .3 cold 356 S .25 ler.ld 25V S .40 40164 .44 40194 .59 NO RANGE .114 .8S 700 8 40174 1.01 40504 59 í016 /512 bit Dynamic pm l.í9 .33 cold 3SV .25 IR r.1.1 25V .45 RLC -200 RED DIf E. CURRENT gEG..I90' 1 cold 75V .15 l'i rrld lOV .40 CONS! BRIGHTNESS 4.511 -sV .25 CAPACITORS MMS369 Divider mDIP 2.44 2.2 mid 206 .25 14 ,,ld 20V .45 RLC201 RID DIEL. CURRENT REG. Crystal 3 -58 MHZ color TV j,.95 2.2 cold 35V 2:1 red .45 CONIO. BRIGHTNESS 4.5 .25 CrVS1a1 2.010 MHZ 3.95 3.7 mid 15V .30 3l rHd 10V .40 CERAMIC DISC RED RL -110] DIII EUII FLOOD .190'' IS 4.7 mid AV .30 5' i.ld 6V .40 Ipl 50V 50V 50V Date sheets on request.Q Add Sot each 6.8 mid 65 .30 Sn 6V .45 82111 82005 GREEN SPOT .790' ./8 ivld Sp/ SON 10001 505' 001111 50V if item is priced below $1.00 each. 6.8 cold 506 .40 I30 15V .50 7p5 55v 12001 50V 0047uí 50V CLEAR POINT 190 .I S IOpf 50V 1500f 50V Oluf 50V FREE CATALOG AVAILABLE ON REQUEST 2zpf .511V 18011f 50V 011111000V LED s EA 27pí 00V 220p1 50V 02201 50V w tL to 3 days Iran 72131 70V 27Opf 50V 030uí 505 DL10A VD C A .27" L810 51.89 Sat star tion guaranteed. Shipment will be made postage prepaid 47pí 50V 39001 00V 050uí 00V DL 707 RED CA .30" RHO 1.49 receipt of order. Payment mas be made with personal check. cha p,r card (include 56pI 9DV 470pí 50V luf SO DL 507 RFD CA .50" RHO 1.49 number and exp. dale). or moves order. Phone Orders - BOIA and E. C , and or C_O.D 6801 00V 600pí 50V FND 359 RED CC .375" RHO .89 QTY. PRICE PRICE DL 702 RID (C .30" L11D 1.39 Add $1.00 to rover shipping and handling it order is less than S10.00 NSN 74R RED CC .30" RHO 1.49 Calilornia residents add sales lay. Ins lude shipping expense for order. 'lipped out of (each) (Minimum 10 DL 500 RED CC cí0" RHO 1.49 U.S. and Canada approx. 10' of order. per value) MANS CRFFN CA .27" [HD 1.39 MANO YELLON CA .27" MD 1.39 INTERNATIONAL ELECTRONICS UNLIMITED DIP] R 0-1U $10 ea MAN82 1ELLOW CA .3" 1.110 1.89 VILLAGE SQUARE, P.O. BOX 449 10.100 $.10 ea 5.05 ea 40ÁN66 RED CA .6" EHO 2.19 O* CARMEL VALLEY, CA 93924 USA 100- 5.04 ea Dual RED CA .b" MD 2.39 Ammo PHONE (408) 659 -3171

CIRCLE 48 ON FREE INFORMATION CARD 109.

www.americanradiohistory.com JAIL BARS AUSTRALIAN MODIFICATION Australian standards? And what is this I've got live jail bara on this Zenith Have I got a dog for you: a Sears 564- piggyback circuit for? -J. C., Ft. Worth, 16Z7C19. I've had them before in the 4005100/101 color set. It was purchased in TX.

20Y1C37, which was a bad horizontal the U.S. then taken to Australia, where it I have a strong suspicion that Austral- blanking diode. This unit doesn't have was modified. . . boy, was it modified! ia is using PAL color standards. This this diode. The horizontal blanking tran- First problem -no sound. I found a system is based on the CCIR system, sistor checks out OK with an ohmmeter. transistor circuit that had been used to with a 5.5 -MHz sound IF (which ac- Any suggestions? -B.H., Modesto, CA. replace an IC. Putting in a new IC and counts for the gadget in the sound). The This has to be caused by the fact that removing the oddball curcuit took care of piggyback circuit should be a PAL color the ringing along the baseline of the hori- that. Now, there's no color unless some- decoder. Your best bet is to take it out zontal pulse is getting through. In this one makes a sound or talks! I get streaks and rewire it according to the schemat- chassis, the blanking is fed into the com- of colors flashing through the picture. I ic. mon- cathode circuit of the difference - checked the color board, which had really amplifier stages (6MN8 tube), but the been modified. This little PC board, with DEFECTIVE TRANSISTOR effect is the same. The transistor could be quite a few transistors, diodes etc., hard- I had a problem with a Harman - leaky, upsetting the bias and not clipping wired in, was in the demodulator and Kardon 930 amplifier. It was pumping, off the baseline. Try a new transistor and bandpass circuits. and the speaker cones moved in and out see if this doesn't help. Is there a difference between U.S. and quite a bit at about I Hz. I found the cause. Regulator transistor TR905 in the DC power supply was a manic depressive! The preamplifier supply goes through it, Seeking Original Japanese Replacement and it was acting up at the I -Hz rate! This transistor checked out OK, of Parts for CB and Stereo Repair Use? course, but a new one cleared up the problem. Figure that one out. (Thanks very much to Danny Biando, Danny Biando Technical Services Co., San Jose, CA, for the hint.)

SERVICE DATA HINT I can't find service data on a Bradford Original Japanese Transistors, FET, IC, Diodes chassis No. 19C-D, model 79772. The ser- CHECK OUR LOW PRICES! vice number is 1171824. Please help. -E.

TRANSISTORS 2SA 816 .70 2SC 403 .59 2SC 871 .59 2SC 1448 1.10 2S0 358 1.30 McL., Lisbon, OH. 2SA 49 .59 2SA 818 1.40 2SC 430 1.10 2SC 897 2.65 2SC 1449 1.00 2SD 380 1.20 2SA 70 1.10 2SA 839 2.15 2SC 454 .59 2SC 898 4.40 2SC 1451 1.80 2SD 382 1.40 Just for luck, I checked the Sams 2SA 101 .59 2SA 841 .59 2SC 458 .59 2SC 900 .59 2SC 1475 1.40 2SD 388 3.40 2SA 102 .59 2SA 847 .59 2SC 480 .59 2SC 929 .59 2SC 1478S .70 2SD 424 8.50 Index. There was nothing listed under 2SA 234 .59 2SA 850 .70 2SC 461 .59 2SC 930 .59 2SC 1509 1.10 2SD 427 2.80 2SA 342 .90 2SA 872A .59 2SC 481 1.80 2SC 943 1.20 2SC 1584 8.50 2SD 525 1.60 I 9C-D, or the other number. However, 2SA 353 .70 2SA 908 11.00 2SC 482 1.50 28C 945 .59 2SC 1588 6.80 2SD 526 1.10 .59 485 2SA 377 2.00 2SB 54 2SC 1.60 2SC 959 1.50 2SC 1624 1.30 2SD 55M 6.80 quite by accident I found the 1 171 B24 2SA 440 .90 2SB 55 1.10 2SC 486 1.60 2SC 971 1.00 2SC 1626 1.10 2SD 610 1.90 2SA 483 3.00 2SB 75 .59 2SC 493 3.90 2SC 983 1.00 2SC 1828 1.30 number. In many cases, you can cross - 2SA 484 2.50 2SB 77 .59 2SC 495 1.00 2SC 984 .90 2SC 1647 .59 FET 2SA 485 2.00 2SB 186 .59 2SC 497 1.60 2SC 1000BL .59 2SC 1689 1.80 2SK 19 1.60 reference these numbers to other names. 2SA 489 1.80 2SB 187 .59 2SC 509 .90 2SC 1014 1.20 2SC 1674 .59 2SK 30 .90 2SA 495 .70 2SB 202 1.80 2SC 517 3.95 2SC 1017 1.40 2SC 1875 .59 2SK 33 1.10 The J. W. Miller Replacement Guide 2SA 496 1.10 258 220 .70 2SC 535 .70 2SC 1018 1.20 2SC 1878 2.25 2SK 34 1.10 2SA 497 1.60 2SB 303 .59 2SC 536 .59 2SC 1030C 2.80 2SC 1882 .45 2SK 40 .70 lists no less than 16 companies that have 2SA 509 .70 288 324 .70 2SC 537 .59 2SC 1047 .70 2SC 1684 .59 2SK 49 1.30 2SA 525 2.50 258 337 1.60 2SC 538A .70 2SC 1080 2.25 2SC 1708 .59 2SK 55 1.30 manufactured sets under the Bradford 2SA 537 2.25 2SB 387 1.50 2SC 562 2.15 2SC 1061 1.40 2SC 1728 2.00 2SK 68 1.30 2SA 539 .70 2SB 3888 2.15 2SC 563 1.10 2SC 1080 4.40 2SC 1760 2.00 3SK 22 2.55 name. Sometimes you can check the 2SA 561 .59 2SB 379 1.10 2SC 819 .59 2SC 1096 1.00 2SC 1775 .45 3SK 35 2.25 2SA 562 .59 2S8 400 .59 2SC 620 .59 2SC 1111 3.40 2SC 1816 4.25 3SK 39 2.25 schematic and photos for a make. 2SA 564A .59 2S8 405 .70 2SC 832A .70 2SC 1115 3.40 2SC 1885 .70 3SK 40 2.25 2SA 565 1.10 2SB 407 1.40 2SC 844 .59 2SC 1116 4.40 2SC 1908 .59 3SK 41 2.50 2SA 588 3.40 2SB 415 .70 2SC 645 .70 2SC 1116A 4.90 2SC 1909 4.40 3SK 45 2.50 2SA 606 1.90 2S8 434 1.20 2SC 650 1.30 2SC 1124 1.30 2SC 1951 1.10 MK 10 2.00 CB RADIO STATIC 2SA 624 1.10 2SB 440 .70 2SC 668 .59 2SC 1182 1.10 2SC 1957 1.20 Iì 2SB 463 1.50 2SC 680 2.80 2SC 1188 .59 1969 4.90 new CB has a 2SA 627 3.60 2SC AN 2140 3.40 This radio problem. 2S8 471 1.60 2SC 684 1.40 2SC 1173 .90 1973 1.10 2SA 628 .59 2SC AN 315 3.70 2SB 472 2.80 2SC 6938 .59 1175 4.40 25 miles hour, there is 2SA 634 .90 2SC .90 2SC 1975 BA 511 3.40 Above about per 258 474 1.20 25C 896 1.95 1177 14.00 2SA 640 .59 2SC 2SC 2028 .90 BA 521 3.70 2SB 492 1.00 2SC 708A 1.90 2SC 1189 1.40 in the receiver. the stock 2SA 643 .70 2SC 2029 3.90 HA 1151 3.70 terrific static All 2SB 507 1.60 2SC 710 .59 2SA 659 .59 2SC 1211D .70 2SC 2091 3.60 LA 4400 3.70 2SB 509 1.90 2SC 711 .59 2SC 1213 .70 have been in- 2SA 683 4.90 2SC 2092 3.90 TA 7045M 3.00 suppression devices 2SB 514 1.90 2SC 712 .59 1222 2SA 886 .70 2SC .45 2SC 2098 3.90 SN 7400 .19 2SB 528C 1.30 2SC 717 .59 1228 1.00 2SA 872 .70 2SC 2SD 28 2.80 SN 7490 .60 stalled- resistor spark plugs, alternator 527 1.90 2SC 730 4.40 2SC 1237 4.25 2SA 673 .70 258 2SD 75 1.10 TA 7055P 3.00 2SA 678 .70 2SB 528D 1.60 2SC 732 .59 2SC 1239 3.50 2SD 90 1.60 suppressors, etc. Nothing works. Any TA 7080P 1 60 2SB 536 1.60 2SC 733 1279 2SA 683 .70 .59 2SC .70 2SD 91 1.80 TA 7061AP 100 B., 2SA 684 .70 2SB 539 4.90 2SC 734 .59 2SC 1308 4.40 2S0 92 1.50 TA 7062 help will be appreciated. -D. Crittend- 4.40 100 2SA 695 .70 2SB 541 2SC 735 .59 2SC 1307 4.90 2SD 118 3.00 TA 7205P 3.90 2SB 554 10.00 2SC 738 .59 1312 en, KY. 2SA 897 .70 2SC .59 2SD 130 1.20 TA 7310P 3.95 2SB 581B .70 2SC 756 2.80 1313G 2SA 706 1.80 2SC .59 2SD 142 2.00 UPC 592H2 160 .90 783 I 2SA 715 1.40 258 584 2SC .59 2SC 1317 .59 2SD 143 2.80 PLL 02A 8.80 This sounds like a classic problem 2SA 719 .70 2SB 595 1.90 2SC 773 .70 2SC 1318 .59 2SD 178 1.40 2SA 720 .70 2SB 600A 7.00 2SC 774 1.60 2SC 1327 .59 2SD 180 2.50 DIODES haven't experienced for a long time. 2SA 721 .70 2SC 183 .59 2SC 778 2.65 2SC 1330 1.50 2SD 187 .59 IS 84 1.00 2SA 725 .59 2SC 184 .59 2SC 778 3.60 2SC 1342 .59 2SD 188 3.00 1S 188 .45 Try this: Run the car up to the speed at 2SA 728 .59 2SC 281 .59 2SC 781 2.65 2SC 1344 .59 2SD 205 1.40 1S 332 .45 2SA 733 .59 2SC 284 1.40 2SC 783R 3.80 2SC 1345D .59 2SD 217 4.40 1S 953 .45 which you hear the noise, turn the engine 2SA 740 2.85 2SC 367 .90 2SC 784 .59 2SC 1359 1.40 2SD 223 1.90 1S 1007 .45 2SA 744 3.70 2SC 369 .70 2SC 785 .70 2SC 1380 1.00 2SD 224 1.90 IS 1209 .45 off and kick it into neutral, letting the car 2SA 745R 4.40 2SC 371 .59 2SC 789 1.00 2SC 1382 .59 2SD 227 .59 IS 1211 .45 2SA 747 5.80 2SC 372 .59 2SC 793 2.80 2SC 1364 1.40 2SD 234 1.00 15 1555 .32 coast. If you still hear the noise, but it 2SA 750 .59 2SC 373 .59 2SC 799 3.60 2SC 1377 4.90 2SD 235 1.00 IS 1588 .32 2SA 758 3.40 2SC 374 .59 2SC 815 .59 2SC 1383 .59 2SD 287 3.70 IS 1885 .45 diminishes or stops when you touch the 2SA 758 5.80 2SC 380 .59 2SC 828 .59 2SC 1400 .59 2SD 313 1.10 IS 2078 .45 2SA 774 .59 2SC 381 .59 2SC 829 .59 2SC 1402 3.70 250 315 1.20 15 2093 .45 brakes, the interference is caused by 2SA 777 1.10 2SC 382 .59 2SC 838 .59 2SC 1403 3.70 2SD 325 1.10 1S 2473 .45 2SA 798 .70 2SC 387 .59 2SC 839 .59 250 1419 1.10 2SD 3580 1.10 1N 34 .25 "wheel static." This static is heard when 2SA 614 160 2SC 394 .59 2SC 870 .59 2SC 1444 2.80 2SD 357D 1.00 IN 80 .25 PRICES MAY CHANGE WITHOUT NOTICE COD ORDERS WELCOMED the wheel rotates and makes and breaks electrical contact with the car body. The IMMEDIATE DELIVERY WITHIN 48 HOURS FUJI -SVEA ENTERPRISE tires then build up static charges. ON ALL TRANSISTORS IN STOCK Dept. Radio Electronics Minimum order $5.00 Ohio residents add Here's the cure: tape off the front 4% sales tax. Box 40325 Add $1.00 postage and handling. Quantity discount prices. P.O. wheel grease caps. Install a grounding ASK FOR OUR COMPLETE PRICE LIST Cincinnati, OH 45240 spring, which is a small spiral spring that MANUFACTURER INQUIRIES WELCOMED (513)874-0220 All Parts Guaranteed Against Factory Defects 874 -0223 tits inside the cap and makes contact with the lathe center of the front spindle.

CIRCLE 102 ON FREE INFORMATION CARD www.americanradiohistory.com Digital Research Corporation JUMBO LED READOUT ARRAY CABLE TIES 1KX8 Most popular size. 33/4" over- 2708 2iC B By Bowmar. .5 in. char. EPROMS common cathode. Designed all for a 3/4" bundle. Ty -wrap Prime new units from a major 1 .: mfg. for use with multiplexed style. Nylon self-locking. 650 N.S. access time. Equivaler 1 four clock chips. Four digits in 100 FOR S1 S8 FOR 1,000 one pack. 1702A's in one package! $1.95 LIMITED STOCK FILTER CAP $15.75 each Mini Size. Axial. 1,000 MFD 7805R HEAVY DUTY 115 VAC RELAY 16 WVDC 4 FOR S1 MOTOROLA By Guardian. Coil is VOLTAGE REGULATOR RED LED READOUT FILTER 115 VAC 60 HZ. DPDT Same as standard 7805 except 750 MA Very handy. Can be used with 10 AMP Contacts. OUTPUT. TO -220. 5VDC OUTI'LT. our Calculator Displays. S .44 each 10 FO 3 $3.95 $1.95 each 2'/4 x '/2 In. 6 FOR S1 1 AMP RECTIFIERS RCA HOUSE M2N3772 OPCOA LED READOUT TRANSFORMER 12 Vac. 600 MA. House Numbe-e'_. Fac- NPN Power Transistor. 30 AMP. SLA -1 Common Anode. .33 In. PRI -115 VAC 60 HZ. tory marked nil -s. All Vastly character size. The original 150 W. VCEO -60. TO -3. out Perfect for clocks or meet 200 PIV minimum. LED display. performs 2N3055. Reg. List 53.04 high efficiency power supplies. Many up to 1,(101: PIV. 2 FOR SI S.75 each 4 FOR $2.50 Small Size. $1.95 30 FOR SI F ill Leads. 741C OP AMPS DISC CAPACITORS HEAVY DUTY TANTALUM TRANSISTC R 2N3566 - - MINI DIP. Prime New .1 MFD 16 V. P.C. Fall Wave Bridge CAPACITOR TO 5 plan tic NPN. Units. Has computer Leads Most Popular 1 MFD. 35 V. Kemet. VCEO -40 HFE 15( TO 600 AMP 50 PIV MFG's house number. Value! P.C. Leads. By 25 Axial Lead. Best Value. 10 FOR S1 S1.25 12 FOR S2 100 FOR SIS Sprague. 20 FOR S1 10 FOR SI HIGH GAIN! TERMS: ORDERS UNDER S15 ADD S .75. NO C.O.D. WE ACCEPT VISA, MASTER CHARGE AND AMER1C N EXPRESS CARDS. MONEY BACK GUARANTEE ON ALL ITEMS. TEXAS RESIDENTS ADD 5% SALES TAX. Digital Research Corporation (FORMERLY DRC) WE PAY POSTAGE! P. 0. BOX 401247 GARLAND, TEXAS 75040 (214) 271 -2461

BOARD TRANSISTOR SPECIALS Full Wave Bridg UNIVERSAL 4K x 8 MEMORY PRINTED CIRCUIT 7N3585 NPN S. TO 66 S 95 PRV 2A 6A 25A 4 1 7 .6 1 7" SINGLE SIDED EPDXY BOARD KIT 2N3777 NPN 5. TO 3 S 1.00 1.30 BOARD 1 16' m... ,,,,..nn. ,, f00 PNP GE 70.3 S .75 B.O a 5/52.60 2N1546 0p -75 - 175 2.00 574.50 7549081'NP S. TO 3 S 1 00 400 .95 1.50 3.00 1 fully 16 address Ones, on 1 322102 buffered. 7 WAT T L D 65 LASER [NODE I R Sa95 2N6056 NPN S. TO 3 D.,.hnn,,m S 70 4 1.20 I. 75 400 board decoding for any of 64 Pages, standard 2N5086 PNP S. TO 92 4 S I 00 600 2N3820P FET S 45 44 Dm buts 2N4898 PNP TO 66 S 60 AUDIO ROMA- AMPS 2N 5457 N F E T S 45 SANKEN 7N404 PNP GE TO 5 5 S 100 ,. ..'-t1'ATTS S795 F8 CPU 2N2646. S 45 1 EXPANDABLE BOARD KIT 2N3919NPNS.TO3RF S 50 WATTS S1595 ER 900 TRIGGER DIODES 4 SI 00 MPSA 13 NPN S. TO 97 3 S 1 00 WATTS 57795 $99.00 2N PROD UJT featuring Fanbug PSU 1K ot staut ram. RS 232 6028 7N3767 NPN 5. TO 66 S 70 POTS interface. documentation, 64 BYTE regster MINIATURE MULTI TURN TRIM 2797772 NPN S, TO 18 S 5 1 00 NTU : T a 100, 1K,2K,5K,10K,25K,SOK,100K, TO 3 S .60 500, 2N3055 NPN 5, 22UF 35V 5'51 00 10UF 1.1V S .25 1 Meg. S75 each.... 3/$200 TO 5 S 1 00 4K BASIC FOR FAIRBUG F8 200K.500K 2N3904 NPN 5, 92 47UF 35V 5 SI 00 22UF2,V S 40 2N3906 PNP S, TO 9? 5 S 100 on paper tales $25.00 x 100 charge coupled device ...SUE 35V 5S100 15UF3iV 1/S1.00 CCO202-l00 7N5296 NON 5, TO 270 S SO image sensor $145 00 'uF 35V 5S100 30UF 6 ' 7/51.00 PNP TO 770 S 5', 4E1 C /MOS (DIODE CLAMPED) 2N6103 5, : 2 U 70V5S100 3' I S 2543638 PNP S. TO 5 5 S I 4 S1 47UF 27` S .35 PC 31.1F 35V 00 4012- .22 4023- 22 VERIPAX BOARD 3 S ' 74010- 22 4046 -2.25 279651 / NPN TO 92 S. 4 7UF 15V 5/51.00 68UF15+ S 50 .40 4024- 75 Th,slloa,d.sa Y l6s ..A. 6e, epu.v 740193- 1.504013- 4049- 40 "BUE 35V 4 S100 4001- 22 4015 - 05 4025- 22 4050- 40 board. 4':' .6 DRILLED and ETCHED TTL IC SERIES 74LS es tlYtaR CIRCUITS 4002 22 4016- .40 4027- .40 4055. -I 50 whech wi11 hohl up to 21 single 14 pin IC's 7400- .16 7445- .65 74151- .65 SERIES u5t25 r416176 631 4017 -1.05 4066 8. 16. or LSI DIP IC's with busses for 74153- a,Sao 76 6s 4006 -1.20 4028- 18 .80 7401 16 7446 .70 65 7Itl 29 power connector $4 00 74154 4,507 76 4t5132 80 9 31 4007- 22 4018 --1.00 4029 1.10 4071- 27 supply 7402 16 7447 .65 1.00 7.L5136 30 74155 a, S03 26 39 It 4009- .42 4019 25 4030. 22 4076 -105 MV 5691 YELLOW.GREEN 7403 .16 7448- 70 .70 4, s138 77 ,rJOB )5 74157 504 26 4010- 42 4020 1.05 4035- 1.10 BIPOLAR LED S 90 7404 20 7450- '15 .65 at SOS 28 4LS139 r 11 75 14161 1 4011- 22 4022- 95 4042- .78 FP 100 PHOTO TRANS S 50 7405 .20 7472 .32 .85. 4, SOB 26 Mt 5151 96 LP 18 2 RED, YELLOW, GREEN or AMBER 7406 .25 7473 .32 74163 .80 a1509 78 NIL 5153 93 19 95 WSIJ 30 Hand wore used 00 l 34 1 05 wrap tool LARGE LED's 6 /S1.00 7407 .25 7474- .32 74164 .95 at 510 26 74LS155 7 r a,511 95 I v 39 110 o unwrap strop # wire 55.30 74165 26 ns156 & 30 I L.5 IMCT2I . S 75 7408 .20 7475 45 1.05 ... . 58 1 40 74173 1.35 at SO 415157 98 MOLEX PINS .... 100/51.00 7409 20 7476 30 7455160 54=70 t 11 I aL515 07 4. 74174 .95 28 DIP SOCKETS 1000/58 00 7410 .16 7480 .45 4L520 26 415141 02 Lr=71 250 CONOUCiDF PIN- 40 7483- 741 75 .90 8 PIN- 2224 10 WATT ZENERS 3.9, 4.7, 5.6, 8.2. 7411 20 .70 aLS71 26 )415187 02 L r =80 95 SPECTRA 74116 14 7485 75 1 7 5 FLAT CABLE PIN - 2528 PIN- .50 12,18.22.100.150 or 200V s.. S .60 7412 20 .87 a, 527 76 7455163 02 1 ÿ _81 7486 74177 75 33 7415168 10 1 75 10'111 50 16 PIN -.2840 PIN - .60 1 WATT ZENERS 4.7. 5 6.10. 12, 15 7413 .39 .30 4L526 17 7489 I 85 74180 45527 33 1L5r49 10 1,4 37 250 100'313 50 30 18 or 22V . ea $ 25 7414 .85 65 7490 7418 4LS30 26 741.5170 77 I M 53 750 MC6860 MODEM CHIP . $9.95 7416 .25 .45 2.00 [-PROM $15.75' 7417 .25 7491 .65 74190 1.20 45532 33 74S173 ]9 I M SS 195 53N 37 455174 OS M 56 95 ,7 A TIC SHOFTRE6 5 Power Rectifiers 16 7497 13 74191 1.20 Silicon 7420 a, 538 37 7415,/5 22 hE.401 275 7513 CHARACTER (:EN S 6.75 7493 45 74192 83 PRV 1 34 174 50A 1256 7425 25 IL S40 27 7455190 50 516 2 00 7518 HEX 3781T SR S 2.50 7494 70 74193 83 14 70 7426 .25 a,542 66 7415191 50 :4 71U71 1074 81 RAM S 1.19 100 06 30 80 3 74194 7427 .25 7495 65 .85 4L5u 79 7:55197 15 54 1 25 1 15 4.25 2.078 S 350 200 07 70 35 7430 16 7496 65 74195 .85 .41.551 26 15193 7s 56 30 MK4008P S 1.95 400 09 25 50 140 6 50 7432 25 14107 28 74.757 .86 4LS54 76 715195 2S '0 9,:

1 '0 25 576U 4K UYNA't11(. HAM S 4 75 600 11 30 70 80 8.50 7437- .24 74121 .33 74279 87 L590 95 7415196 99 15 1101A -256 BIT RAM S 75 10 7438 24 74123 .65 75491 ,.S7J 0 14L5197 99 800 1" 35 90 2 30 50 50 ur V m S74 40 NIL 5721 1 25 3, PROM S 6 95 I 75 17 7440 74125 40 7,A.5 MM5203 UV 1000 : 45 IO 2 -0 16 SO 40 '415257 1 4 74176 .ILS? 35 1 7026 UV PROM S 95 7441 70 .40 41590 B9 4L5758 1 ]8 1]10 25,. PROM 95 SILICON SOLAR CELLS 74150-1.10 9. 5704 41( 510 '442 .52 444 597 85 7415779 75 :d 82S23 .. S 1.95 2'a" diameter 41593 BS 74,5365 66 i 4 d 57 AY S 1013 UART 5 6 95 M7001 ALARM CLOCK CHIP S 75 415109 43 NIL S366 66 J7-046 4V at 500 ma $4.00 41511? 43 L5367 66 390 LIGHT ACTIVATED SCR's REGULATORS MINIATURE DIP SWITCHES 5113 43 66 9119CC ]9, 7 Iowa TO 18. 200V IA S 1.10 MOM 6571a 9 upp. ,490 94, 309K . S 95 340K 5,17.15 c7í2Mr<1a 94 $10,5 nt.^ 723 S .50 or 24V S 85 1166 E.9ht SPST swItchö ,n a 16 Din 0,0 acka9e 32.20 51.7A81 nPTICAtjufaa 5, 50 LM 376 . .. S .60 3401,5. 6, 8, 12 IIMITStY1Tera 320K-5 or 15V S110 15,18 or 241/$1 10 t l A loa 25A READOUTS 3207.5. 15 78 MG 51 35 75. LED .7 1,.t4r,. S 3 S. 100 40 70 130 41 50 170 r 79 MG S 1 35 FND359CC S 50 DL704,3"CC S 95 o 24V $1.15 " 200 70 1 10 1 75 61 70 1 6p ' U14 E TOGGLE SWITCHES FND 70 C C 1" $ 55 MANS7 3" C A S 95 RS232 DB 25P male $2.95 MI A 1065P0T S120 400 1 10 1.60 760 1 01 20 720 FND 503 C C 5' S 85 NS33J dig .array S 75 OB 255 female $3.50 NIT DPDT SI 70 FND510CA S'S 85 DL 747 C A 6" S195 CONNECTORS 206

WE SHIP OVER 957. Terms: FOB Cambddpe. Mass Send 256 for our catalog featuring SOLID STATE SALES Sled Chock 0r Mousy Order OF OUR ORDERS THE Transslors and Rectifiers P.O. BOX Include Postapo, Minimum 145 Hampshoe St., Cambridge, Mau DAY WE RECEIVE THEM Order $5.00. COD'S $20.00 45 SOMERVILI E74D, MASS. 02143 TEL. (617) 5474005

CIRCLE 38 ON FREE INFORMATION CARD www.americanradiohistory.com

NOW -THE 8K LOW POWER RAM - $159.95 ULTIMATE RAM BOARD Imsai -Altair - S -100 Buss compatible, uses low power static 21 L02 -500ns fully MEMORY CAPACITY INTERFACE CAPABILITY buffered on board regulated, quality MEMORY 32K FOR $475.00 ADDRESSING Control, data and address inputs plated through PC board, including solder MEMORY WRITE Buy an S100 compatible 8K Ram Board and utilizes low power Schottky mask, 8 pos. dip switches for address select. PROTECTION upgrade the same board to a maximum of deviens. 8K, 16K, 24K, 32K using Mos. 32Ke in steps of 8K at your option by merely Fully assembled and tested. Not a kit. tek MK4115 with 8K bound - purchasing more ram chips from S.D. Sales! At POWER REQUIREMENTS aires and protection. Utilizes a guaranteed +8VDC 400MA DC DIP price - Look at the features we switches. PC board coma +18VDC 400MA DC 4K LOW for have built into the board. POWER RAM KIT with sockets 32K operation. -18VDC 30MA DC Orders now being accepted Fully Buffered - on board regulated - re on board regulation is provided. allow 6 to 8 weeks for delivery. PRICES START AT $151. FOR 8K RAM KIT duced power consumtpion utilizing low On board (invisible /refresh is Add $108.00 for each power 21 L02 1 500ns RAMS additional 8K Ram provided with no wait states or - - Sockets Available the 1st quarter of cycle stealing required. provided for all IC's. Quality plated through 1978: 16K, 32K, 48K, 64K Board fully assembed and tested for $50. extra. MEMORY ACCESS TIME PC board. "Add $10. for 250ns using Mostek 4116 with 16K IS 375ns. RAM operation boundaries and protection. Memory Cycle Time is 500ns. 8K FOR $151.00 The Whole Works - $79.95 Z -80 CPU BOARD KIT - Complete Kit $139. MUSICAL HORN

o ne tune supplied with each kit. Additional tunes - $6.95 each. Special tunes available. Standard tunes now available CHECK THE ADVANCED FEATURES OF OUR Z -80 CPU BOARD: -Dixie - Eyes of Texas - On Wisconsin - Yankee Doodle Expanded set of 158 instructions, 8080A software capability, operation Dandy - Notre Dame - Pink Panther - Aggie War Song - Yellow of from a single 5VDC power supply; always stops on an M1 state, true sync Anchors Away - Never on Sunday - Rose generated Texas - Deep in the Heart of Texas - Boomer Sooner on card (a real plus feature!), dynamic refresh and NMI available, Bridge over River Kwai - CAR & BOAT KIT HOME KIT either 2MHZ or 4MHZ operation, quality double sided plated through PC board; parts plus sockets priced for all IC's. `Add $10. extra for Z -80A chip $34.95 $26.90 which allows 4MHZ operation. Z -80 chip with Manual - $39.95

Jumbo LED Clock Kit - $16.95 FEATURES'. DIGITAL LED READOUT A. Bowmar Jumbo .5 inch LED array. 6 DIGIT ALARM CLOCK KIT B. MOSTEK - 50250 - Super clock chip. THERMOMETER - $29.95 Features: Litronix dual 1/2" displays, Mostek C. On board precision crystal time base. 50250 super clock chip, single I.C. segment D. 12 or 24 hour Real Time format. Features: Litronix dual %" driver, SCR digit drivers. Greatly E. Perfect for cars, boats, vans, etc. simplified con- F. PC board and all parts (less easel inc. displays. Uses silicoaix single struction. More reliable and easier to build. Alarm option - $1.50 chip CMOS A/D converter. Kit includes all necessary parts (except case). AC XFMR -_ $1.50 Kit includes all necessary parts P.C. board and Xfmr optional. Eliminate the has (except case); AC line cord sle - avoid the 5314! Do not confuse with Non - and power supply included. Alarm kits sold by our competition! Bowmar 4 Digit AC XFMR - $1.50 $12.95 kit LED Readout Array 5 Digit Countdown Utility 6 Digit General Purpose 4 JUMBO .50" DIGITS ON ONE STICK! or WITH COLONS & AM /PM INDICATOR Darkroom Timer Kit - $44.95 Computer Timer Kit - $29.95 $3.95 Features: Large LED l/a" displays. crystal Fealui rs Large controlled Mostek LED displays, Mostek 50397 counter 50397 counter display display /driver, counts up .pIÍ river, set timer at 0.1 second precision to 59 minutes, 59.99 seconds with 1/211 Y. from crystal controlled Full Litronix Jumbo Dual 0.1 second to 59 minutem 59.9 se 1/100 second accuracy, operates on 115V AC l. . or and, 5A -115V relay Included to control 12V DC supply. Use it to time photographic enlarger, telephone calls, athletic events, sun lamp, appli- practice time, school and laboratory LED es TV, r other equipment, operates demonstrations, Digit Displays on 11 5V AC, displays tan be turned off experiements, chess games, etc. Time computer functions in real for total darkness applications, r n simple time such as times on programs, sub routines and DL 722 - C.C. DL 728 - C.C. push button operation, use other n kitchen, computer controlled events. Requires two output school, office or laboratory All nec- channels for DL 721 - C.A. DL 727 - C.A. parts included. special design case start /step and clear controls. All necessary parts included. Special ií.75 design case $3.75 99c $1.29 Low Cost Cassette Interface Kit Microprocessor RAM's $14.95 Azst Support Chips Features: K.C. standrad 2400/1200 Hz, 300 .. I 21L02 - 500NS 8/11.50 Baud, TTL, I/O compatible, face lock loop, 21 - L02 250NS 8/15.95 22 pin connector. Feeds serial data via micro- 8212 - I/O port 3 50 2114 - 4K 14.95 processors I/O ports and from cassette tape 8214 -PIC 12.95 1 101 A - 256 8/$4.00 recorder. $14.95 8216 - Non Invert Bus 4 95 1103 - 1K 99 8224 - Clock Gen 4 95 MK4115-8K 19.45 8226 - Invert Bus 3 95 74S - DISC CAP % PIO 200 256 3 95 1000 MFD for Z -80 14.95 ASSORTMENT CTC for 39 MFD FILTER CAPS Z -80 14.95 PC leads. At least 16V Mallory 8228 Sys. Controller 8 20 10 different values. Rated 35 WVDC. Electrolytic Upright style with 8251 Prog. comm. interface 10.95 Includes .001., .01, 15/$1.00 8255 Prog. perp. interface 13.50 .05 + other standard PC leads. Many pop- 8820 Dual Line Recr 1 75 CPU's values 60/$1.00 ular values. 4/$1. 8830 Dual Line Dr 1 75 JOY STICKS! RESISTOR * FLAT PACK 2513 Char. Gen 7 50 Z -80 includes manuel 4 -100K ASSORTMENT 5400 SERIES 8838 Quad Bus. Recvr 2 00 39.95 74LS138N Z -80A includes manual 44.95 POTS PC leads 20 asst. devices - 1/8 decoder 99 8T97 -Hex Tri -State 8080A CPU 8 BIT 11.95 $3.95 each A good mix of for $1.00 Buffer 1 25 1488/1489 RS232 8008 CPU 8 BIT 6 95 values. SPECIAL! 1 50 200/52.00 TR1602B Uart 3 95

P.C. LEAD POWER RESISTOR ITT PART NO. DIODES 15 OHM SAJ 110 Counter Chips PROM's 1N4148/1N914 25W by Ideal for electronic 100/52.00 CLAROSTAT music circuits 75c Each 7 stage freq.dividers. 49c each 1702A - 1K - 1.5us 3 95 or 10/35 MK50397 6 Digit elapsed timer.... 8.95 2708 - 8K Intel - 450ns 14.95 MK50250 Alarm clock 4 99 ITT DUAL 11 t: GENERAL 5204 - 4K SPRAGUE DUAL >k MK50380 Alarm chip 2 7 95 SENSE INSTRUMENT 95 ß2S129 -1K 2 50 AMPLIFIER DIFFERENTIAL MK50396 6 digit up /down counter 12.95 AMP. TD101 DIODE 2708S - 8K signetics 650ns 9 95 75234 and 75235 1N82AG MK5002 4 digit counter 8 95 49c each 49c each 19c each MK5021 - Cal. chip sq. root 2 50

60 DAY MONEY S. D. An Empire Ind. Inc. iggrimsbmm/ SALES CO. Co. BACK GUARANTEE! Call in your Visa or Mastercharge NO COD's. TEXAS RESIDENTS ADD 5% SALES Texas Residents call Collect: TAX. ADD 5% P. 0. BOX 28810 -C in on our Toll Free Watts Line: OF ORDER FOR POSTAGE & 214/271 -0022 HANDLING. ORDERS UNDER $10. ADD 75c DALLAS, TEXAS 75228 1- 800 -527 -3460 HANDLING. FOREIGN ORDERS - US FUNDS Dealer Inquiries Invited! ONLY! I Choose $1. Free Merchandise From Asterisk Items on each $15. Order!

CIRCLE 58 ON FREE INFORMATION CARD

www.americanradiohistory.com gE 1.OS Radio 21¡ amp. 1000 PIV TT =SPECIALw Motorola Hep o170 7400/9002 NVNDER I0'$1.00 Hut Only 6/$1.00 7410/9003 5o )' 0$1.00 7420/9004 0 °$1.00 Money back guarantee. NO COD'S. Texas resi- dents add 5% sales tax. Add 5% of order for po- 7460/9006 6 °$1.00 stage and handling. Orders under $ 15.00 add 75 ITT MOS TO cents. Foreign orders add 20% for postage. 7430/9007 0'$1.00 For your convenience, call your Bank Americard LED DRIVERS 7440/9009 "0'$1.00 or Master Charge orders in on our Toll Free Watts Line: 1-800-527-2304. Texas residents call ITT 501 Quad Seg. Dr. .35 74109/9024 3'$1.00 collect: 1-214-271-8423. ITT502 Hex Digit Dr. .49 74195/9300 211.00 P.O. Box 38323R Dallas, Texas 75238 ITT503 Quad Seg. Dr. .49 9000 Series parts prime rom ITT506 Hex Digit Dr. .49 ITT. Pin for pin compatible ITT508 8 Digit Dr. .49 with 7400 numbers shorn n. UNSCRAMBLER .49 Plugs into earphone or external speaker jack of ITT509 8 Seg. Dr. any Scanner or Monitor. Guaranteed to un- ITT511 Quad Seg. Dr. .55 scramble any 1085 call. ITT514 8 Digit Dr. .59 60Hz CRYSTAL Easily tuned TIME BASE Full instruction We have 100's of thousands of the above This kit enables a MOS cic« k :ircuit included O' ' C)13 Drilled fiberglass P.C. Board listed parts. These parts 100% prime just to operate from a DC powe s wrce. One Hour Assembly C) under mil. spec. rating. Ideal for car, camper, van, t oat, etc. 60Hz ouput with an accuracy of Punched Case triN .005% (typ). Low power con- LOOK AT THIS SPECIAL MA 1003 sumption 2.5 mA (typ). Sna size HUT will fit most any enclosLn'. Single FROM RADIO J MOS IC oscillator /divider chip 5 -15 Power Supply Kit: 5V1 amp reg. IK Car Clock volts DC operation. Line regulation .005% From National includes Load regulation 50mV Kit includes components, PC board, transfor- specs. and 3 switches oN $5.95 each mer, fuse and pilot Light. Line cord not included. L(.)(.)K Only $6.50 Only $17.95 2 $10.001011 ó fo r BESTSELLER!

VARIABLE POWER SUPPLY KIT NO. 1 LED'S L (s) (s) K Continuously variable from Drilled fiberglass TO-220 5V to 20V P.C. Board Excellent regulation up Case Included Jumbo Reds 8/$1.00 to '/z Amp 4400 Mfd of filtering Jumbo Green 5/$1.00 regulatorE. Kit includes all components One hour assembly Jumbo Amber 5 /$1.00 Mini Red 8/$1.00 7805 Pos. 5V 1 Amt .99 This model will power a 5 watt transistorized CB Radio Mini Green 6/51.00 7806 Pos. 6V 1 Amt .99 Pos. 8V 1 Am; .99 ONLY $10.95 Mini Amber 6 /51.00 7808 7812 Pos. 12V 1 Am{ .99 VARIABLE POWER SUPPLY KIT NO. 2 Mini Clear 6 /51.00 Bi -polar Red /Green .99 7815 Pos. 15V 1 Am; .99 Same as above but with a 1 Amp output, also with case Bi -polar Red /Red .99 7818 Pos. 18V 1 Am; .99 ONLY $13.95 7824 Pos. 24V 1 Ami .99 7905 Neg. 5V 1 Arrmp 1.10 7912 Neg. 12V 1 Amt' '.10

74L500 .21 74L5145 00 CMOS TTL *r. 74LS02 .21 74L5151 70 74L503 .21 74L5153 70 CD4000 .19 74L504 .28 LS 74L5155 69 7400 11 1486 28 CD4001 .19 74L505 -28 74L5I56 7401 .0 7489 1.25 70 CD4002 4AVE 74L508 .21 74L5157 75 .19 Capacitors 7402 13 7490 .65 74LS09 .28 74LS158 71 7403 13 7491 .61 CD4006 1.20 74L510 21 85 7404 15 7492 .43 74L5160 gob 74L511 21 74=5161 CD4007 .19 7405 .13 7493 43 85 74L513 .45 741..5162 85 4.7 mfa 10V Tant. 5/1.00 7406 .16 7494 .67 CD4009 .47 74L514 .99 74L5163 85 7407 .21 7495 .67 C D4010 .47 CD4043 .60 22 mfd 10V Tant. 5/1.00 74L515 .26 74L5168 85 7-:08 19 7496 .67 C 74L520 .24 74LS169 85 CD4011 .19 D4044 .60 22 mfd 250V Axial 4/1.00 7409 .19 74100 .28 74L521 .28 74L5I70 1.69 CD4046 7410 .13 74104 .49 C D4012 .19 1.50 25 mfd 25V Axial 4/1.00 74L522 28 7411 .18 74107 .28 74=517'3 1.10 CD4047 74=526 -32 C D4013 .32 1.89 47 mfd 25V P.C. Razia 4/1.00 7412 .13 74109 .22 74L5174 00 74L527 32 CD4049 7413 74121 .29 74LS175 81 CD4014 .78 .49 50 mfd 25V Axial 5 /1.00 .37 74L530 .26 74L5190 7415 .27 74122 .39 95 C D4050 .49 68 P.C. Razia 74LS32 32 74L5191 CD4015 .78 mfd 25V 8/1.00 7418 74123 .48 95 .75 74L537 .32 74L5192 CD4016 .32 C D4051 1.25 1000 mfd 25V P.C. Rae la 5 /1.00 7420 .13 74124 .48 95 74L538 .32 7421 .13 74136 .80 74L5193 95 .95 CD4052 1.25 1000 mfd 35V P.C. Ras la 4/1.00 74L540 .26 CD4017 7423 74141 .75 74L5194 95 .25 74L542 65 C D401 8 .95 CD4053 1.25 7426 74151 -61 74L5195 85 .24 74L551 .26 CD4055 74153 .61 74L5I96 85 C D401 9 .45 1.25 7427 19 74L554 26 7428 .15 74154 .98 74L5197 85 CD4066 74L555 .26 74L5251 CD4020 .97 .78 7430 .13 74155 .58 85 74L573 .35 74L5253 CD4071 .19 7432 .23 74156 .58 74L574 81 CD4021 .97 35 74L5257 71 CD4076 7433 .28 74157 .55 74L576 49 CD4022 .97 1.00 7436 74L5258 71 Special Devices .35 74160 .55 74L586 36 74L5260 26 .19 CD4081 .23 7437 .23 74161 .55 CD4023 74L590 .55 74L5266 7438 23 74163 .55 26 CD4507 1.00 74L592 .55 74L5279 CD4024 .75 7440 13 74164 .85 55 C 74L593 .55 74L5290 CD4025 .19 D4508 2.80 82523 32x8 Prom. 2.19 7441 74175 .85 75 .76 74 =5109 38 74L5293 C 7442 .47 74180 .67 61 D4510 1.10 74L5112 .38 CD4027 .45 2513 Char. gen. 10.00 7443 .59 74191 .98 74L5295 95 C D4511 74L5113 38 74L5298 CD4028 .89 1.10 7444 .59 74192 .79 95 8T97 Tri -State Bu 1.25 74L5114 38 74L5365 CD4516 7446 74193 .81 55 CD4029 .99 1.10 .68 74L5125 .47 7447 .68 74194 .81 74L5366 55 CD4520 1.10 2102 -1 500NS .99 74L5I26 .47 74L5367 55 CD4030 .35 7448 .71 74195 .69 74L5132 79 CD4528 .87 7450 .13 74H00 .18 74L5368 55 CD4035 .99 3.57945 color xtal 1.25 74LS133 35 7451 .13 74H05 .29 74L5390 1.75 74CO2 .25 74L5136 .37 74L5393 C D4040 1.00 12V Relay 4PDT New 2.75 7453 .13 74H20 .29 1.45 74C04 74 =5138 .71 74L5670 2.30 CD4041 .69 .32 7454 .13 74H21 .29 74L5139 71 74C107 MM5316 Clock 3.75 7460 .19 74H40 .29 CD4042 1.05 .79 7470 .27 74H50 .20 7472 25 74H53 .29 7473 .29 74H61 .25 7474 .29 74H72 .45 7475 .47 74H73 .39 7476 .31 74H74 .39 -2301 7480 3 /1.00 1_800 -527 .31 9316 RADIO HUT 7481 1.10 9601 3 /1.00 7482 .S7 9L04 .35 P. 0. Box 38323 Dallas, Texas 75238 Lise Our Toll Free Watt § Line 7483 .67

CIRCLE 59 ON FREE INFORMATION CARD

www.americanradiohistory.com PRECISION POTS ACOUSTIC COUPLER BY NOVATION ASSORTMENTS (BY SPECTROL) HEAT SHRINK TUBING ASST. $2.95 This originate only coupler was manufactured for use These 10-turn, mo el 534, 25 -6" lengths In arsoua sines and colora in T.I. 725 data terminal. It is compatible with Bell f are 4-5 %ces. and _.25% lin. 103 and 113 data sets or the equivalent. The coupler i^h1lil' (.750 "x.875 "dia.) Available TEFLON TUBING ASST. $1.95 operates a II asynchronously to maximum speed of 300 in 5K, 10K, or 50K.$2.50 21 -6" lengths in various sires and colora baud in the full or half duplex mode. All signal Any 10 for $19.95 outputs are compatible with TTL. Transmit freq. is IN PRECISION RESISTORS 2111) FOR 5.1.95 1270hz. for mark and 1070hz. space. Receive freq. a for These 10 -turn, model 860, Assortment contains balanced insenlory is 2225hz. for mark and 2025hz. for space. Unit requires are +_1% res. and '-.25%-- lin ±12 +5 tae L13. WELL MIXED ELEC.IRONIC volts volts for operation. Compbte with schematic Available in 500 ohm or and all pertinent information. Fully reconditioned, calibrated, IIARUW ARE $1.00 1K. 54.95 each and guaranteed. HIGH POWER RECTIFIER RS232 TO TTL RS232 P.C. BOARD AND SCHEMATIC IIIK QIIYf LINEAR l'll'l' WITH TO CONVERTER KIT. $4.50. VARO H407 6000V 750MA. OMPLETE KIT WITH COMPONENTS $6.50. '/a v 1a4" SII AFT S.75ea. 1(1 FOR $1!)5 $2.50 EACH ARNOLD HEWLETT PACKARD CORE aaV LITTLE VINYL FEET M PHOTOFLASH CAP 135 NH. PER 1001) TURNS. 1rSelf stick.ng square or round HP n 7730 .3" CHAR. REIZ, ID x I 601 MED 360 VOIT I" X 3% "L. I" -7/8" ODs 3/4" THK. feet. 1 /2" x 3/16 "h. COMMON ANODE SI.50EA. PrN A- 759135 -2 51.50 EA, Sheet of 50 for only $1.00 $1.90 EACH 111 EOR $15.00 1 FOR $3.95 100 FOR $98.00 1 STANDARDS KIT PRINTED CIRCUIT BOARDS MINI KIT liptk ''f) PITTMAN 12V DC MOTOR G-10 1/16" UNETCHED COPPER CLAD An assortissent of precision components for calibration 60117,. CRYS'l'AI. TIME RASE 1 OZ. 2-SIDED OR 2 OZ 1- SIDED. The Pittman runs of SPECIAI, OFFER ON MINI SIZE 10 100 lesi equipment. on as low as 2 Kit includes assorted KIT INCLUDES MM5369 AND 2.50 19.95 1101 volts, rated 12VDC :3579.5156117. W1T11 51.95 1 CRYSTAI. ACE makes it easy with etch ponder. 4.00 29.95 I'. capacitors. 101 assorted 250 ma, 2.8 oz. in. SCHEMATIC S') 95 F. A. Etch 'em to your own specifications. 4.00 29.95 0.01'. resistors. and III of torque at 5000rpm. 1.1/8" 4 "x12" 5.00 3995 temperature compensated dia. x 2" long with 0.118" EP-1 MAKES 1 0 T $1.50 POWER CORDS v bene, reference diode. shaft. New and guaranteed. EP-2 MAKES (GAL $3.50 Contact Ace, for quotes on custom sizes 62" BLACK OR WH TE (with instructions) ONLY S6.95 10 FOR ONLY $2.95 10 for 515.00 PERMA -FLEX KYNAR WIRE WRAP WIRE Thermalloy p/n 60305. TAIT SLOTTED OPTICAL SWITCH (OPB 800) O:,. s Solid silver plated 30 AWG Id al for flat power 314 ?A wide 66' long. All weather The OPB 800 consists of a available in BLUE. RED. devices. 1 "w x 1.1/8 "h. 8000V LOKI if k I black. YELLOW. BLACK. GREEN. 5.25 each 10 for $1.98 SI -00 /roll 57.95/10 roll, gallium arsenide infrared LED UL coupled with an NPN silicon OR WHITE. EAGLE -PICHER APPROVED 100' SPOOL 52.50 photo-transistor in a plastic CF6V5, 6 volt housing. The gap in the housing 500' SPOOL...... S5.95 5 A.H. spill- proof, STACKED FOI1. CAPS MILLER provides a means of sensing motion of 1000' SPOOL 5995 rechargeable battery CHOKE )legalized pol, rar hon rs Oh opaque objects. 5" mounting centers. 26 AWG RED OR BLACK $12.50 each +tack (nil construction. P/N 6310 10 FOR 52.95 Manufactured by OPTRON INC. 500' SPOOL 57.95 10 for $99.95 Extreme') low selfinduclion. 1392 TURNS 50 MH. 65 MA. New year 51.98 EACH 1000' SPOOL.. 512.50 -1 warranty 100/S1.10 I1111(1 /S 1 2.50 T FLON U81 MOLEX I.C. PINS G.E. SC51B TRIAC Extremely high engratiinertness. SI(M,'s 31'í)T KF I.AY 100 FOR 5.98 1000 FOR SO.95 15A 200V in press range and chemiopcal Will nemperatureot BISMUTH P/N 30603. 1205 1C. ALLOY fit case. Ideal for crack or become brittle. Remains Melts In ®water. 4 oz. roil li ge Contacts boding SPECIAL OFFER ON N9I46 1?/ flexible throughout entire operating color organs. 51.00 4 rated 10 -\ at 285 D1-/ ingot for $395, 1 lb. ingot 10 FOR $7.50 100 FOR 54.95 11)00 FOR 539.95 , temp. range. CLEAR 18 GA. for To Play . 52.95 I 155 It. I I pin plug -in. S9.95. Fun With! 100' roll $4.95 1000' roll 524.95 w!!!!!!!!!!!!1M 7 H t5:a NATIONAL MM5013 1K SHIFT rG-0 REGISTER. 8 PIN MINI DIP 6Bi1 U/A l:on.erler IJ pin r mic $.60 EACH 10 FOR $4.95 ACE ELECTRONIC TERMS: MINIMUM ORDER $10. Send check or package. r 11.50 I. s. . money order. NO COD. Texas residents add 5% MOTOROLA 1-WATT AUDIO sales tax. Canada and Mexico add $2.50. Over - IN'LEI. 03106 RVM PARTS AMP. SAME AS MFC6070 IN = seas countries add $5.00 for surface rates. We MO speed full. decoded 5400 MITCHELLDALE, B -8 AN 8 PIN MINI DIP IW /DATA) 256hí1. I( pin er mo 17131 688-8114 pay portage up to 10 pounds. HOUSTON, TEXAS 77092 $.49 EACH 10 FOR $3.95 acka e. $1.98 EA. a

CIRCLE 38 ON FREE INFORMATION CARD

(ECTIFóERS JAPANESE TRANSISTORS more than For For 2SA484 3.00 25C482 1.75 25C12264 1.25 25D170 2.00 e00 2544,95 1.65 25C495 1.10 25C1237 4.50 25D180 2.75 20,000 different 2SA497 1.00 25C517 4.25 25C1239 4.00 25D188 .96 1 144004 .90 8.00 254634 1.25 25C6344 .65 25C1306 4.75 1.00 9.00 254636 1.25 2SC710 .70 2SC1307 5.75 251)234 1.00 p 1.10 10.00 254673 .85 2SC711 .70 2SC1377 5.50 2513235 1.00 com onents 0E01 1.20 11.00 254878 .75 2SC735 .70 2SC1383 .75 2SD291 .85 0 25A682 .85 2SC756 3.00 2501448 1.25 MRF8004 3.00 254683 .90 2SC778 4.00 2SC1449 1.30 MPS8000 1.25 254699 1.30 2SC781 3.00 25C1678 5.50 MPS8001 1.25 2546994 1.45 25C789 1.00 25C1728 2.15 MPSUO2 .50 VOLT. REG 5400 2SA733 .65 2SC798 3.10 25C1760 2.15 MPSU31 4.00 SERIES OEM SPECIALS 2SA777 LM340K3 .90 2SC799 4.25 2SC1816 4.50 SK3048 3.25 1.95 5400 1.00 25854 .70 2SC1000 .65 SK3049 4.75 5404 25C1908 .70 LM340K8 1.95 1.25 1N34 .25 2N29054 .30 2143903 .16 25856 .70 2SC1013 1.50 SK3054 1.25 LM340K8 1.95 5410 1.00 2SC1909 4.75 1H80 25 2N2906 .25 2N3904 .18 2S8186 .60 2SC1014 1.50 2SK19 1.75 LM340K-12 1.95 5426 1.25 2SC1967 1.50 2N2908Á .30 2N3905 .16 258187 .60 25C1017 1.50 2SC1973 1.50 25K304 1.00 LM340K-15 5473 1.50 1.95 1N270 .25 2142907 .25 2N3906 .16 255324 1.00 25C1018 2SK33 1.20 LM340K-18 5475 1.50 25C1975 4.90 1.95 1.50 1N914 .10 2N29074 .30 2N39544 3.75 2SB370 .65 25C1061 1.65 2SC2028 25K41 1.75 LM340K-24 1.95 5486 1.90 1.10 214173 1.75 2142913 .75 2N3955 2.45 258405 .86 2SC1079 3.75 25C2029 3SK22Y 2.75 LM340T0-5 1.75 5493 2.00 4.75 214404 .75 2142914 1.20 2N3957 1.25 258415 .86 2SC1096 1.20 2SC2091 1.10 35K40 2.75 LM340T0-6 1.75 54100 1.80 214443 2.50 2143019 1.00 2N3958 1.20 256461 1.25 2SC1098 3SK45 54LSO4 1.15 2SC2092 4.75 2.75 LM340T08 1.75 1.00 2N508Á .45 2143053 .30 2144037 .60 255483 1.65 25C1115 35K49 LM340T0-121.75 2.75 25D72 1.00 2.75 214718 .25 2N3054 .70 2144093 2SB507 .90 2SC1170 4.00 25D77 1.00 3.00 LM340T0-15 1.75 4004 214930 .25 2N3055 .75 2144124 .16 2SC371 .70 2SC1172 4.00 25088 1.50 3.00 LM340T0-18 1.75 4005 2N958 .30 2N3227 1.00 2N4126 .16 2SC372 .70 2SC1173 .95 2SD92 40081 1.50 LM340T0.24 1.75 1.50 2141302 1.25 2N3247 3.40 2144141 .20 2SC481 1.85 25C1209 .75 25D118 3.25 40082 3.00 2141305 .75 2143250 .50 2144142 20 2141540 .90 2143393 .20 2144143 .20 2141544 .80 2N3394 .17 2N4220A .45 JAPANESE CIRCUITS 7400 TTL 2141560 2.80 2143414 .17 2144234 .95 7400 .18 7442 1.08 74107 49 2141605 1.75 2143415 .18 2N4400 .16 AN203 3.75 LA4051P 4.65 TA7045M 3.50 UHI C004 9.00 7401 .21 7448 1.15 74121 .556 2141813 .50 2N3416 .19 2N4401 .16 AN208 4.75 LA4400FS 3.80 TA7055P 5.50 UPC41C 3.95 7402 .21 7450 .26 74122 .49 2141711 .50 2N3417 .20 2144402 .16 AN210 3.10 LA4400FR 3.80 TA7060P 1.85 UPC563H2 8.00 7404 21 7451 .27 74123 1.05 2142102 .70 2N3442 1.85 2N4403 .20 AN214 4.90 LD3120 3.10 TA7081P 2.25 UPC566H 2.25 7406 .24 7453 .27 74125 .60 2142160 .70 2N3553 1.50 2N4409 .16 AN241 3.20 M5115PR 4.80 TA7063P 2.25 UPC575C 4.10 7407 .45 7454 .41 74126 .81 2142218 .26 2143563 .20 2144410 .16 AN315 3.50 PLL01A 13.50 TA7075P 4.90 UPC595C 3.60 BA511 PLLO2A 7408 .25 7460 .22 74132 3.00 2N2218A .30 2N3586 .20 2144441 1.00 3.50 12,00 TA7089P 2.90 UPC1001H2 5.15 7409 .25 7472 .39 74141 2N2219 .25 2143638 .20 2144442 1.15 BA521 3.95 PLLO2A-G 12.00 TA7120P 2.20 UPC1008C 6.00 1.15 HA1202 7410 20 7473 .45 74150 1.10 2N2219Á .30 2N3642 .20 2N4443 1.35 3.10 SG613 5.40 TA7150P 4.55 UPC1020H 5.50 7411 .30 7474 .45 74151 1.25 2N2221 .25 2N3643 .20 2144852 .55 HAI 306W 5.20 STK011 10.50 TA7153P 6.90 UPC1025H 5.50 7413 .85 7475 .80 74153 1.35 2N2221A .30 2N3646 .20 2N5061 .30 HA1308 4.50 STK015 6.50 TA7203P 7.00 UPC1156H 6.50 7416 .43 7482 1.75 74154 1.54 2N2222 .25 2143648 .14 2145064 .50 HAI 322 5.20 STK032 14.20 TA7204P 6.50 UPD277C 4.50 7417 .43 7483 1.15 74157 1.30 2N2222A .30 2N3731 3.75 2N5130 20 LA1201 4.25 STK050 24.50 TA7205P 6.50 UPD857C 19.00 7420 .21 7486 1.12 74181 1.45 2142270 .40 2143740 1.00 2195138 .15 LA4031P 3.50 STK056 11.35 UPC16C 2.50 UPD858C 13.00 7422 1.50 7486 .45 74164 1.65 2N2369 .25 2N3771 1.75 2145298 .50 LA4032P 4.50 STK415 8.50 UPC20C 5.00 UPD861C 22.00 7425 .43 7489 2.49 74165 1.65 2142484 .32 2N3772 1.90 2145306 .20 7427 .37 7490 .69 74166 1.70 2142712 .18 2N3773 3.00 2145400 .40 7428 .35 7491 1.20 74174 1.95 2142904 .25 2143819 .40 2145401 .50 7430 .26 7492 .82 74175 1.95 2N2904Á .30 2143823 .70 2145457 35 7432 .31 7493 .82 74180 1.05 2142905 .25 2N3868 1.25 2N5458 .30 7437 .47 7494 .91 74181 3.55 7438 .40 7495 .91 74191 1.50 N.J. residents tax, 'nTI NEW-TONE add 5°6 sales . ti "' 7440 .21 7496 .91 74195 1.00 d 7441 1.10 74100 1.25 74197 1.00 All orders add $1.00 Postage $1.50 Canada minimum order $5.00 =®; ! ELECTRONICS PO Box 1738A Bloomfield, N.J. 07003 PARTIAL LISTING WRITE FOR FREE CATALOG Phone (201) 748 -6171, 6172, 6173 CIRCLE 24 ON FREE INFORMATION CARD

www.americanradiohistory.com uuuuuAAuuA 6LAA, ELECTRONIC TOUCH ORGAN KIT DIGITAL CASSETTE TAPE IC -60 Fantastic new design uses CMOS I.C. and a to- COMPUTER RECOF DING i1 .. tal of 39 semi- conductors to give a touch con- All these tapes made it J S.A. Cre- _T trol keyboard, all the electronic parts in one PC by a top cassette tes e Co. -, Board. This organ is easy to build, yet has fea Never Recorded -Reg, ' i6.110 ea, 'N. .,t,^¡,,. c1.¡ 3 peeks/$5.00 Lures like a full two- octave range touch key- board, variable tremolo; two voices; built -in I.C. Can be used in Auih.: volume with Recording as we I amplifier with control, complete ::si i we.r Nor speaker and a specially designed plexi -glass case. SOUND ACTIVATED SWITCH .1 parts completer" C EATTERIES NOT INCLUDED f PCs, `Ideal kit for beginner or gift for children á24.50e0. SCR w turn relay` o r esa- other for sec .IW¡v nee NO Ideal for use es door alarm, sound c led toys many other 30MHZ FREQUENCY COUNTER KIT Sup °S t$° 0'..- $1 ]5 aa. /2 br 53.00 Take advantage of this new state . of -the -art counter featuring the many benefits of custom LSI circuitry. This new technology approach to instrumentation yields enhanced perfor- ncer smaller physical size, drastically reduced power consumption (portable battery Sub -Mini Size operation is now practical), dependability, easy assembly and revolutionary lower pricing! Condenser Microphone 0.5" red LED 6 digits display $2.50 each 5O Resolution: 1 Hz at 1 sec. 10 Hz at 1/10 sec. FET Transistor Built -In Only $ 59 Sensitivity: 10 My RMS to 30 Hz Internal power supply: 5.2V at 1 amp regulated Input connector: BNC type SIGMA 78RE1, 12DC RELAY Includes all parts, SPDT Model 250 -30A PC Board and Transformer Input power required: 117V AC 50/60 He 4008 COIL Diode protected for over voltage input $1.30 ea. or 10 for $10.00 NEW UNITS CALCULATOR MECHANICAL DIGITAL CLOCK ALL BRAND with STOPWATCH WITH DAY AND COMPUTER GRADE CAPAC ITO SS 6 Functions with % and memory DATE OF THE WEEK 5,650 MFD60V $2.2 10,000 MFD 50V $3.2'. 8 Digits big green display rI «k n Iawpfvllr D moor e: from high gullltr äe cat alloy. Movement is - 11,500 MFD 75V $3.9' Built-in X'tal controlled stop the popular nip MK NM aback up kohl 34,800 MFD 50V $4.2 ". e. watch to 1/10 a count of second. 39.000 MFD 12V $2.0r Special Price Only Supply Voltage 110V AC. limited quantity $15.50 ea. 100,000 MFD 6V $3.5i: re. $16.50 Ea. BATTERI NOT INCLUDED QUARTZ CRYSTALS CLOCK KIT TV Games PCrPIELAR 1 MHZ $495 MOST !watt AUDIO AMP 2 MHZ $5 25 MM531' KIT All parts are pre assembled 4 MHZ $5.25 10 MHZ $5 25 on a mini PC Board 3 579 MHZ $1 25 Calmat Voltage 9V D.C. Colo, TV Type Supply 6- Sales Only MM5314 Cioc Chm Pc Boa.rr SPECIAL PRICE $1.95 ea, lorme, 6 Green Color 0 3 adco.s ELECTRONIC $19.50 r ,. ., r 2W + 2W STEREO AMP SWITCH KIT RATYRO : yenr°b Special Only 3'415 ea. All parts completed On a PC Boern 4 Games - Tennis, Hockey, CONDENSER TYPE 2 LM380 I.C., volume, Racquet Handball and Sin- bass, treble control included Touch on Touch Olf gle Handball. MINI -SIZED II.I:.

Supply voltage: 9 15V D.C. ane 7473 I C Auto counter display On Sensitivity: 100Mv for Lull output d 12v relay the screen AM RADIO Total harmonic distortion $5.50 each a 1 % @1 KHz @1.5watt Size smaller than box cf ra chest! D Ou short cdcuit protected Receives all AM stat on ST 2 WIRE ONLY $5.75 ea. VHF MODULATOR Batteries and ear phone i,_I _tied For TV Game or Computer WRAPPING AUDIO AMP KIT Thu the SW hp. toRFiSignalido TOOL Only $8.50 2 l.M 380 with v plume Control Vidd Input IVOC RF Output 1.5 M' Power Supply 6^'18V DC 6125 MHZ khan al $29.50 MHZ only $5.0041. ONLY $4.50 Wire Wrapping TI 1955 In Bulk r Alternative AY3 8500 1 TIMER KIT 6 Game 128 Pin Dipl 100' $2.00 CtMIR.I uI1 WIT IY, Controlled from 1- 100sec. T V Game Chip with Data 500' $8.50 vnl Time Tennis Squash hockey, Ideal to be used as time delay practice & 2 shooting.

nit for burglar alarm, photo Special041111 Only $6.50 Sub Mini Size service, and other purposes PC Board for TV Game with Data $2.50 ea PANEL METER loading 110V, 2 AMP h TV 51.25 ea 500 UA Max. Switch Boa between Game TOGGLE 51111CH Supply voltage 12 18V D C ONLY $1,20 ea

aifsize 01 submini r >gys ay 40 LECTRO IC IC Tt $11.50 each RCA STEREO AM -FM rated 3 amp 125V :C MUX TUNER AMP POWERT TRANSISTORS t 10C199 MJE2955 PNP -a MOTOROLA s ELECTRONIC ALARM SIREN E3055 NPN 2a32P SpsT C 9C 080 MS 244 SPDT t DC 090 COMPLETE UNIT 10 AMP 60 VOLT 90 WATTS PER PAIR MS 245 DPI, 120 1 10 for an Alarm Uni, $225 Ideal use LARGE GUANTIT' AVAIL hookup to your car back ull or FOR OEM to make e reverse indicator TRANSFORMERS Light Output up to 130 dB Voltage Supply 6-12V 5 Watt Per Channel RMS With ALL 117 VOLT INPUT SUBMINIATURES 11 OGLE AU -999 8 Track Tape Player Built In 15 $30.00 ea. ITC esWM S Manufactured by RCA, maker of 30v at amp 36V CT at 3 amp $ 4 -50 ea. SPOT C,r. SO 19 KEY HEXADECIMAL Quality Systems. All Solid State 50V CT at 2 Same $ 4.50 ea. pPOT CIT 50 ea rs, SPOT On ON t is.. PAD Circuitry with Beautifully detailed 48V CT at 2 same S 4.50 ea. j KEY panel. Limited Quantity. 12Vor24V at 2 amp $ 3.90 ea. 1 Homekey 24V CT at 800MA $ 1 80 ea. -0 ONLY $53.50 ea. `j r Aiso A ai.oie et , r,r P re ABCDEF e-4Key 0.8V 12V at 400MA S 780 ea SPECIAL $10.50 ea. ON- SCREEN TV AC POWER SUPPLY CLOCK KIT Adapter Type PPLonner Ja O+(STV ICm Low Cost Hexadecimal 16 Key Pad 12V AC Output 200 MA 0y0K Same one as in July Radio pnil vary ratesterz Designed for Colcula,or $2.76 seek 0,0 for Computer Electronics. K it includes PC ,ic.y o Can be usea 6V DC Output 130MA $1.90 ea. Data Entry Pad or Digital Lock Board, MM5318 and MM5841 All key tops blank with super 87VDC Output 130MA $1.90 ... ,,,"7:`,,r7:7° c "'"ei re good tourte feeling ea. chip. All other electronic parts 100MA $1.90 ea. *AN $5.50 50.95 with transformer. 12V DC Output s ONLY $21.00 PUSH -BUTTON ! W ITCH DIGITAL ELECTRONIC LOCK KIT 150UA METER N /() pen Cyr r_ pr autp ienition. BIPOLAR LED Color: Red, Wt-' -0. Blue, $6,50 ea. door, burglar. alarm, etc Jumbo Size red /green change color only Green, Black. 4,51.00 At. 4 Digits Progremeb le ,o N /Close ai ro Any Combination when reverse polarity of voltage. - $1.50 ea. Available S'le ea. 4006 RELAY AND KEY PAD NOT Ideal for go /nogo indicator. INCLUDED LARGE OTY AV Sik aeLE Two for $1.00 POWER SUPPLY KIT SO UA PANEL METER SOLID STATE ELECTROVI; IIZZER 0.30V D.C. REGULATED I.C. TEST CLIPS F dm Uses ÚA723 and ZN3055 Power m rScalend from Oma 10 :/1 S,.unio voltage' 12V Saine es the E Z cl be Y TR output can be adjusted from or n be erased s n your i. \D/ for With Long Leads Irreal Our 0 -30V, 2 AMP. Complete with PC 20" own put on top tlBrand or Tone In, Caine new ,r board and all electronic parts. In Black and RM Colors box $2.75 per pair Only $3.80 ea. $1.50 edl p T4 POWER soPPLY $9.50 each eear x Transformer for Power Supply, 2 AMP z4V 2 $4.50 ea. MINIMUM ORDE R Sto 00. Calif ornra res,dann add 6% sa Is tae Panel Meter t.,77 30V DC $4.20 All orders add 10% oostage for out of state Overseas countries add 15% of total order for postage SEND CHECK OR MONEY ORDER TO MA1003, 12V DC CLOCK MODULE

nc in a "' y -t_ Built X'TAL controlled : time base. Protected against 114 FORMULA INTERNATIONAL IIIC. MIEW t- automotive volt transients. 11` 2603 CRENSHAW BOULEVARD HAWTHORNE CALIFORNIA 90250 Automatic brightness con- For more information please call 12131 6795762 green color : -r- trot with 0.3" STORE HOURS 10 -7 Monday Saturday BANEE®IlKAMENIO AO display. Display turnoff $19.50 with ignition "OFF ". 11111=11 VVVVVVVITVV

CIRCLE 74 ON FREE INFORMATION CARD

www.americanradiohistory.com ALL TOGETHER NOW! The acclaimed Equinox 100 mainframe kit ($799) is now Jim-Pak AUTHORIZED a complete S -100 system. DEALERS Because now there is an Equinox 100' I/O interface kit electronic components ($120) that handles the hard work of interfacing all your, For peripherals. And Equinox 100" 4K memory kits ($109). Assembled 8K ALABAMA memory boards ($188). ECU/ATE" editor /assembler and Mobile Lafayette Radio Electronics BASIC -EQ" software on cassettes. faster CALIFORNIA It all goes together. It all works together. It's all together Berkeley Al Lasher Electronics now at special system prices. Monterey Zackit See The Equinox System's at your local computer shop. Palo Alto Zack Electronics Call toll -free to 800 -648 -5311. BAC /MC accepted. Or write service Sacramento The Radio Place Equinox Division, Parasitic Engineering, P.O. Box 6314, Sacramento Zackit Albany California 94706. San Carlos J &H Outlet Store San Francisco Zack Electronics Sunnyvale Sunnyvale Electronics Vallejo Zackit Walnut Creek Byte Shop Computer Store USE FLORIDA Tampa Microcomputer Systems GEORGIA Atlanta Atlanta Computer Mart HAWAII ZIP Aiea Delcoms Hawaii Honolulu Integrated Circuit Supply ILLINOIS Evanston lily Bitty Machine Co. CODE INDIANA East Chicago Acro Electronics Corp. Hammond Quantum Computer Works LOUISIANA Baton Rouge Davis Electronic Supply Co. MARYLAND Baltimore Computer Workshop of Baltimore on Rockville Computer Workshop MASSACHUSETTS Medford Tufts Electronics MICHIGAN all Lansing Fulton Radio Supply Co. MINNESOTA Duluth Northwest Radio of Duluth Eagan Dacom Amateur Radio Ctr. MISSOURI mail Parkville Computer Workshop of Kansas City THE EQUINOX SYSTEM'- When you put it together, it's really together. MONTANA Billings Conley Radio Supply CIRCLE 62 ON FREE INFORMATION CARD NEBRASKA Lincoln Altair Computer Center * * * * * * * * * * * * * * * * * * ** * * * * * * * * * * * * NEW JERSEY Hoboken Hoboken Computer Works NEW YORK the 4th Annual NOLIDAY SPECIAL Albany Fort Orange Electronics New York Computer Mart of New York New York The Computer Store t a 1wß Four 8Kx8 ECONORAM II Troy Trojan Electronics White Plains The 1:. Computer Comer OHIO oes kits-- -now only $415.00! Cincinnati Digital Design You read it right - --32K of memory for $475. OKLAHOMA

i - But price isn't the only reason to go Godbout; Oklahoma City Bits, Bytes & Micros

- -: look at our features. We're fully buffered OREGON 4- (with tri -state outputs), fast (under 450 ns), Beaverton Altair t Computer Center 11 dl - ' ' low power (guaranteed under 11/2A), fully static R ,{ PENNSYLVANIA for no timing hassles, S -100 compatible, the Murraysville Computer Workshop of Pittsburgh ability to handle DMA devices, sockets for all RHODE ISLAND ICs...this is a board you can depend on. Cranston Jabbour Electronics City Pawtucket Jabbour Electronics City COMING ATTRACTIONS: Another Special: "Grand - TENNESSEE We'll be happy to supply your Heath Memphis Sere-Rose & Spencer Electronics iii with 12K of memory for $235, which Son of a Cheap Ckxku Oak Ridge Computer Denn is what Heath charges for their 8K TEXAS hoard. Watch this space... Dallas Computer Shops Inc. 1,8432 MHz Xtal; HC6 w/ wire leads $5.95 .S " MUM Houston Altair Computer Center W Houston Interactive Computers iF VIRGINIA Alexandria Computer Hardware Store tl 11 y Springfield Computer Workshop of Northern Virginia Assembled stereo U WASHINGTON 2W amp uses L31380 Bellevue Altair Computer Center '1) ' ICs. Volume, tone Longview Progress Electronics and balance con - Reduced to $10.95! phis is our pop - WEST VIRGINIA trols. Ideal for alar 6 digit, 0.4" readout clock at Morgantown The Computer Comer a special price. Includes 12V battery use, transfor- Morgantown Electro Distributing Co. music miniamp, h mer, PC board, time set switches, E CANADA more. Only $10. :ill parts. Less case only. Alberta, Calgary The Computer Shop FOREIGN France, Paris Computer Boutique New from YECIroR.. VP2 ASSEMBLED MICROCOMPUTER CASE...as VISIT I -__ _ __ . - DEALER adjustable packaging system for S -100 ®D@®09 - buss microcomputers. Card guides and BILL GODBOUT ELECTRONICS BOX Y OUR hardware for 12 cards, with provision 2355, OAKLAND AIRPORT, CA 94614 electronk for 21 cards total on .75" centers. TERMS: Prices good through end of magazine cover date. Instantly accessible interiors with Cal res add tax. BankAmericarde /VISA® /Masterchargee JIM -PAK, 1021 HOWARD AVENUE, slip out covers; sturdy chassis plate orders ($15 min) call (415) 562 -0636, 24 hrs. Allow up for power supply. And...it's really to 5' shipping (more for power supplies); excess re. SAN CARLOS, CALIFORNIA 94070 beautiful $134.30 funded. COD orders OK with street address. CIRCLE 47 ON FREE INFORMATION CARD 4E1, A, A, A, A, A, *A, A, A, A, A, A, A, .AI *A, A, A *A, A, Ass CIRCLE 44 ON FREE INFORMATION CARD

www.americanradiohistory.com ATTENTION DEALE Sr Announcing 111 Pai electronic components One -Stop Component Center

=Over 20] quality items in- A component n_ of proven clud ng integ-ated circuits, sellen develo3e: for the resistors, diodes, transis- independent dealt-. Ideal for tors, caJacltors, connect - computer sho s. school ors, switches, sockets, LEDs and Data Books stores, electro is dealers, :ove-ing all JIM -PAK hobby shops, or nr location

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elettroni: buyers in dealers' make initial in a lation of area. the JI111 -PAK e easy. *Naticnal adiertising cam- paign in leading electronics Your 7. ustomers r eserve the magazines to include list of qualify ng dealers best. Now you ca profitably retail lame brand compon- *Nationally known man u- factu-ers "products at prices ents at competi i.e prices. every dealer can afford Be the first in lut area to

*Guaranteed products annouce and se I the JIM. *Standard industry pa-t PAK line. Wri te or call lumbers today. Jim-pak FOR MORE INFORMATION AND PRICING SCHEDULE CONTACT: =---= a division of James Electronics, 1021 Howard Avenue, San Carlos, California 94070, (415; S2-8097

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www.americanradiohistory.com AVANTI® (CO-INDUCTIVE design of this ASTRO PLAjJ- patented antenna gives long \range, noise free CB Base performance.

Antennas give The result of years of research L cevelopment, the ASTRO PLANE has to radiation which means that your signal gets out from the highest part of you patented your antenna. Your signai radiates about 15 feet higher than with other antennas which radiate near the bottom. performance! The ASTRO PLANE has a lower angle of radiation which makes more efficient use f the radiated signal by allowing it to hjc the curvature of the earth instead of shooting your power up into the sky.

The ASTRO PLANE has 4 46 db ga n Dyer i hotropic which gives you a stronger signal and better, clearer reception. You'll get long lasting, touble free performance because it is compact in desigi -- without long drooping radials, without cci s to burn or short out, and with direct grounc to help dissipate static charges aid lightning. Stainless steel radials concentrate signal power on top Rigid heavy -city aluminum tubing No long drooping radials to ice up or break off So unique it's backed by a U.S. patent (Patent #3587109) No coils io burn out or detune Easy assembly Lightweight - easy to install on simple pipe nasi

n no OED rpo DC Q fli oo x_: O)c irill=3 n 11°CD °Ill 0 II= Ordinary collinear or ground plane ante va signal> are b ocked...they radiate from the bottom.

n 3 co O. C a o - .il °_°d °a ill ASTRO PLANE gets its signal over cbstscles_.it ad ates frcm the top.

SPECIFICATIONS Total Length - 12 'eet Velica Polarity Weight -4 lbs. Aircra:t Cuality Alu ninum Power Gain - 4.46 db SWR - Fre -tuned - Less Impedance - 50 -52 ohrrs than 1.2 1 Omnidirectional - neecs rotor band width - full 40 channels

high TM performance ( C_OINDüGTIVE ) ntennas

Avanti makes a complete line of high performance mobile CB antennas and accessories. For five catalog, write:

creators cf !Ie fario i. AVANTI RESEARCH AND DEVELOPMENT; INC., 340 Stewart Avenue. Addison, IL 60101

©Copyright 1977. All Rights Reserved CIRCLE 20 ON FREE INFORMATION CARD www.americanradiohistory.com