LOWDOWN ON RADIO PEKING "IT'S TOO NOISY" ALARM SWL ANTENNA BRIDGE IN-CIRCUIT IC "TELLTALE" BUILD ADJUSTLESS NEW TOUCH CONTROL
TEST EQUIPMENT - TOOLS EXPERIMENTERS & LAB SUPPLIES u ELECTRONIC 7.' ";<, , r"'l '" iIi "4".t.44,vir
'v." R2 1. - G. R3 Cie 00 yf _ ,so70ul I, OPERATION ASSIST Through this column we try to make it possible for readers needing informat
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IC'S FOR THE EXPERIMENTER (Continued from page 33) between J1 and the board audio input. Don't forget to solder the 1.1 tap to t
librar c " cs FET PRINCIPLES, EXPERIMENTS, AND PROJECTS by Edward M. Noll This book covers the principles of operation of the field -ef
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The New 1969 Improved Model 257 A REVOLUTIONARY NEW TUBE TESTING OUTFIT 411' ' s .R ® COMPLETE WITH ALL ADAPTERS AND ACCESSORIES, NO &apos
PRODUCTS (Continued from page 22) between 12 and 16 volts) ; 2- ampere maximum output current; 10- transistor, three -diode (one zener) circuitry; f
1 9 6 9 POPULAR ELECTRONIC ELECTRONICS EXPERIMENTER'S HANDBOOK SPRING EDITION 11.AS BUILD 60 -WATT GUITAR AMPLIFIER WITH FUZZ, REVERS AND TREM
Words are inherently limited in stimulating the emotions aroused by music. This is especially so in describing how high fidelity components perform. W
¡near for Cs the Low -cost package Experimenter IC's has many uses -like building an FM wireless mike April, 969 By this time, most everybody
© O O gilioK D21 16 Q 0 0 0 0 TAB 910 1 os 07 5 o 20 $% BOTTOM VIEW Fig. 1. The KD2116 consists of four closely matched npn transistors arranged
o o Y TAB BOTTOM VIEW o o o o Fig. 3. The KD2115 is com- plete audio amplifier in a TO -5 can. When driven from a low -level signal, this IC
O KD2114 O 0 0 02 o o SUBSTRATE TA B BOTTOM VIEW 10 Fig. 5. The KD2114 also contains four npn transistors, arranged as an isolated pair and a
Fig. 7. The wireless microphone is built perf-board style as shown here. Also shown is the suggested component place- ment. However the circui
You get more for your money from NRI_ more value, more solid experience so essential to careers in Electronics. NRI's pioneering "dis
A metal strap arrangement can be mounted on the rear of the plas- tic case so that the wireless microphone can be carried on the user&apos
microphone jack Ji and power switch S1 (if used) at the other end of the plastic case. If you use the microphone called for in the Parts
Build a Pos-Neg Pulse Generator INDISPENSABLE TRIGGER SOURCE FOR DIGITAL CIRCUITS BY FRANK H. TOOKER R2 4.7K NEG C2 .01yF POS cl .O229F R3 4.7
LI SOmH CI .022yF DI C2 NI91 1000 pF SI R4 4.7K 02 R2 IOK VI R3 RS 20K 4.7K BI 9V C3 1000 p1< S2 /' OUTPUT 82 0 SD E 81 01 Q2 Fig. 3. With t
One of our students wrote this ad! Harry Remmert decided he needed more electronics training to get ahead. He carefully "shopped around" fo
and the material had always seemed just a little beyond my grasp. Score another point for CIE. Another thing is that CIE offered a complete
Which Transformer Is Which? BY ROBERT P. BALIN Transformers are used in electronic circuits to change voltages, couple signals, match im- pedances
10/tliA ElffT49Nlt 0.1 UNIVERSAL FREQUENCY COUNTER Popular Electronics Un ¡'versal yrequency Counter BY DON LANCASTER Part 1 Note: Constructio
I FIG tH S2D 1I7VAC 60 nJONLY II LINE S2 S2 ND + 3.6 A A/I0 B B/10 -0 D _ D GATE -0 D/10 - C -0 C/2 - 0 M2 SCALER 0 0 N ZU' ? + N M7 POWER SU
PARTS LIST COMPLETE COUNTER C1 -1 -AF, 400 -volt Myfar capacitor 11- 14 -6.3 -volt, 50 -nu l pilot lamp and lens as- sembly, three green, on
POPULAR ELECTRONICS VOLUME 30 NUMBER 4 APRIL, 1969 WORLD'S LARGEST -SELLING ELECTRONICS MAGAZINE SPECIAL FEATURE LINEAR IC'S FOR THE EXPERI
M5 Fig. 18. Author's prototype may be duplicated or used as a guide. Because of the length Fl of M7, the Power Supply mod- ule, it is
wave with a frequency 1/10 that of the input. It should be about 1.8 volts in amplitude and have a 6:4 duty cycle. This, of course, is also th
Build VHV Supply 10,000 VOLTS FROM COMMONLY AVAILABLE COMPONENTS BY PAUL H. FUGE THERE STILL EXISTS a real need for very- high -voltage power suppl
,4'-x FR'.t?fewrF ?NLkk ASE SOUND LE:' Build the G'amtro! Rumpus Roma Noise BY A. J. LOWE April, 1969 DID YOU EVER wish you kne
JI MIC Fig. 1. A low -cost commercial transistor amplifier saves a lot of wiring. Besides its use in noise control, the circuit can also
particular amplifier in your project. In most cases, this will be a common type of high- impedance microphone. The au- thor used a low -cost
HOW IT WORKS Room sounds are picked up by the microphone and passed through the LEVEL control to the audio amplifier module. The load for
Medical electronics now measures eye !movements caused by that tipsy feeling BY DEAN WARE
DID YOU KNOW that, when you are dizzy or when you are dreaming, your eyes "beat" involuntarily? (They rotate slowly in one directio
THE UBIQUITOUS VOM is one of the handiest pieces of test equipment available to the electronics experiment- er. Although useful in a thous
measure The RCA WV -38A Voit- Ohm Milliammeter is a rugged, accurate, and ex- tremely versatile instru- ment. We think its your best buy. On
OFF BI H 1}- SA *IN5297 J3( PE. OFF 01 EXT. J4 P2 RI len XI SIB _L* - I- 2 Fig. 1. Two things make this ohmmeter different 56K x100 from other
CALIBRATION OF OHMMETER X1 SCALE X100 SCALE Resistance Meter Reading Meter Resistance Reading 102 .16 500U .095 20 .275 1000 .165 30 .365
BY L. G. STRIGGOW CONTROL UP TO 200 WATTS WITH A FINGERTIP ELECTRONICS experimenters are al- ways looking for new ways to con- trol the light
LINE D3 105059 R3 R6 27K IK --L Ci1 .225F SCRI CG DI 6el 10 5059 R2 05 105059 117 2.7K .7K D5 VAC G C 2N4990 C ' UP TO SCR2 - 200W LOAD CI R
ANODE GATE ANODE OA CATHODE CATHODE HOW IT WORKS Operation of the touch control circuit depends on D5, a silicon unilateral switch (SUS). This
"THIS is 111010 PEHINII" IGNORING INTERNATIONAL RADIO TREATIES IS A FAVORITE -A::TIC ASTERN, sometimes harsh female voice comes on t
including simultaneous multi- frequency transmissions. Its international pro- grams were aired in 31 foreign lan- guages, ranging from Tagalog (
of Czechoslovakia, Radio Peking started special transmissions in Czech (3 hours weekly) , Polish (2 hours weekly) and Rumanian (2 hours wee
6 good reasons to get into electronics: 62 POPULAR ELECTRONICS
Want more reasons? Read on... A future? Electronics is the future. Build your career in a field that's growing this fast, and you should
Sound us out ...and you will be listening to the most brilliant sound reproduction you can get from an auto- matic turntable. The BSR McDonald
SìmpIe5I Antenna Bridge GET THE MOST OUT OF YOUR SWL ANTENNA SYSTEM THE SWL who wants to put up a home- made resonant antenna has two strikes aga
Construction. Referring to the photo. mount BNC connectors J2 and J3 on the top of an appropriate -size metal utility box. Then mount JZ
Popular EleComics GTzON cit, I -_=I \ Well, the surprise is the price. They're 75 dollars. i'it, ,,;ii 11- i Ì \ _'_i 1- 11442.:
T HE INCREASING use of digital IC's in many experimenters' projects has created a need for a low -cost in- or out - of- circuit te
(oE p CO 60TTOM VIEW OI PROBE TIP 10K PARTS LIST 50- (íÛ -m:l pilot lamp (#4S, -49, or similar I 01,02-- Tronsislor (Motorola D!!'S.ì$93) 11
PARTS LIST CI,C2-5 -,.F, low- ,oftage elerlrulytie capacitor Q1.Q2.03 --Transistor ( Motorola í111'S3393) R1,R5- .___1200 -olnn. S; -uwtf resi
° o 1±2 source of 3.6 volts ( the same voltage used for the IC circuit). The lamp should glow and be plainly visible at the top of the probe. T
propriate hardware at each corner. Drill a hole in one end of the chassis to accept a small rubber grommet. After tying them in a knot to provi
When testing an IC out of the circuit, plug it into the proper socket, make the connections called for in the test table, apply power, a
ÄÌV Electronic %JunUtIcw Control TAKE NIGHTTIME NATURE PHOTOS ELECTRONICS has always been an im- portant factor in the development of new hobbies
NOW! An outdoor antenna you don't have to mount on the roof All channel color TV WINDOW ANTENNA outperforms any indoor antenna! Here's th
Fig. 1. Once system is tripped, relay operation is in numerical sequence. As K2 closes, it pulses shutter solenoid; K2 provides the power-
---------------------- 1 3" 1/4"DIA Fig. 3. Fabricate light shields illustrated here from mailing tube; note aperture disc on short tub
(SEE TEXT) f ( vz STEEL PIN PLUNGER 5/32" DIA FLATTEN - DRILL d TAP FOR 6 -32 THREAD 6 -32 SCREW Fig. 5. For proper solenoid operation,
PARTS/METHODS/IDEAS/GADGETS/DEVICES tips& techniques HOMEBREW BATTERY TERMINALS Where space isn't at a premium, AA battery terminals such
80 in rn in 1 O) O) 0? O) ... O N CO 1C1 .-i In N Il) W) = ñN CO. Ñ M.. n O^1 M1\ IntO in ñ 2 .r . ^' 1+Ì O) ^1 N .-. N N Ñ in ^ 1lj .. .r
the product gallery REVIEWS AND COMVENTARY ON ELECTROLIC GEAR AND COMPONENTS TERADO TRAY- ELECTRIC (Power Source Model 50 -160) Most inverters (12
TERADO TRAV -ELECTRIC (Power Source Model 50 -160) Self -contained Trav- Electric inverter weighs about 29 lb. A 43 -plate garden tractor wet b
Crystal -controlled tuning module is actually a whole "front end" featur- ing fractional microvolt sensitivity and high tolerance sta
AMATEUR RADIO By HERB S. BRIER, W9EGO Amateur Rodio Editor NEW NOVICE LICENSE ELIGIBILITY OPERATION RETREAD has been ap- proved. Effective January
to remain unidentified, predicted today that the recent spectacular successes in the United States space program may result in more efficient high
makes first class soldering the easiest part of any job w r41.1,.,; .. The original Dual Heat Soldering Guns Preferred by technicians for their fa
point, except Novice contacts count five points. Contacts between New England and foreign stations count three points. Stations outside of New E
%HORT-WAVE LISTENING By HANK BENNETT, W2PNA/WPE2FT Short. v " A HAM SPEAKS FOR SWL'ING SOME WEEKS ago our mail contained an interesting
10 Reasons why RCA Home Training is your best investment for a rewarding career in electronics: Performing transistor experiments on programmed bread
IILEADER IN ELECTRONICS TRAINING When you think of electronics, you immediately think of RCA...a name that stands for dependability, integrit
India News Service, New Delhi, 15,290 kHz, at 1000; and Pyongyang, North Korea (call - sign dubiously listed as KCNA) on 16,402 kHz, with no
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,y% \:: !' c%:::iII `...,''>- _.. '' . ; : ' ¡ 4 ji¡: ¡ 1i :::t i.::::.. - . ip; ,;:; í °¡\ %í;1::111 `\ SOLID STAT
L r - GND 50pF L R3 IOK LI CC /250p3 {\ --vWJVNP RI 2.5 MEG. _ DI CI MIMI IN34A 365 pF C5 .OIyF R4 4 7K 4J_ 5K t C3 IOyF Li9 Fig. 2. In this two
NEW HOLLOW SHAFT nutdrìver set Oh lockout/Screw atliusling lealure Speeds, simplifies setting of combination lock -nut /slotted screw adjustments on
Cost Control Circuits," a section of Seminar Applications booklet No. 671.9, published by General Electric's Semiconductor Products D
Youcanpay6OOand still not get professionally approved TV training. Get it now for 599. Before you put out money for a home study course in TV Ser
introducing .. S -DeC breadboard i1 dr for easier circuit building An S -DeC contains 70 push -in contact points which are arranged in two sets of
associated with the acoustic wave penetrates the semiconductor material and provides a transfer of energy. Diffused silicon planar epitaxial pow
computer to work to solve the problem. Af- ter reducing the original list to 15,000 "most - popular" types, and supplying performance,
dering flux. Hold the end of the copper braid against the soldered terminal and apply the hot tip of your soldering iron against the back
0150" 7.1.91 Fi l in coupon for o FREE One Year Subscr p- tien to OLSON ELECTRONICS' Fantastic Value Pccked Catalog -Unheard of
SHORT -WAVE LISTENING (Continued from page 93) kHz, is often good in English at 0030 -0100; they run until 0345 Sunday with a live dance
New C outdoor speaker in timeless redwood $1 4.95 Audiotile net Silicone- treated speaker. 10 -watt, full- range, 8 -ohms. Handy, built -in volume c
Mozambique -The "A" Program of R. Cluse do Mozambique has dropped 3265 kHz and is now scheduled on 4925 kHz at 1630 -2100, on 6115 k
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NTS COMPUTER ELECTRONICS This is the future. And it's hap- pening now. The number of com- puters will increase many times in the next few
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