Saroc

These being days of impoverishment, I had not intended to make the scene at Vegas. At the last minute Ken put on the pressure and, with the hopes of perhaps selling a page or two of ads to help balance the books, 1 hopped oil down there. Just after taking off from Boston I had a short contact with WITNO through tile W1ALE repeater in Concord. N.H. No answers at Schenectady . . . some short contacts in western New York . . . Cleveland was kept busy willi long-winded nonlistening talkers . . ....

Audio Mixer

Marlboro MA 01752 Paul Hoifman W1ELU 169 Millham St. Marlboro MA 01752 The audio mixer described in this article, although designed primarily for repeater use, can be used anywhere it is desired to mix a number of audio inputs with a high degree of isolation between inputs. The mixer is adaptable to almost any configuration which may be required to suit the individual's requirements. The number of inputs can be increased by a factor of two or three to suit the...

Al

Over 250 Pieces of USED EQUIPMENT on SALE Be sure to check this list over 20,000 worth of good used Receivers, Transmitters and Transceivers offered at these reduced prices While the stock lasts let us serve you Sandy Jackson mgr T.T.Freck W4WL FRECK RADIO & SUPPLY COMPANY 38 BILTMORE AVENUE ASHEVILLE, NORTH CAROLINA 28801 5 DIGIT READOUT WITH 8 DIGIT CAPABILITY - .0005 ACCURACY - PORTABLE MODEL 5-30 30 mhz multifunction counter. Frequency, period, ratio, scaling, markers. Frequency range 10...

Communication Engineering Laboratories

TV And Communications Antennas Since 1921 Asbury Park, New Jersey 07712 201-775-7252 M With 81 miles of sic trails, serviced by 16 aerial lifts, Mt. Snow is now ranked as the world's busiest sjci jt resort. Where the trails come together at the summit, the WA1KFX machine reliably repeats FM signals Fjfrom J46.31 to 146.88 MHz month in and month out, in weather where zero is considered viarm. Installing and maintaining a repeater on an isolated mountaintop usually means a lot of lonely hours for...

Features

1 Radio Amateur News Page i Never Say Die 1 The World of FM 6 Letters to the Editor 8 Caveat Emptor 8 Leaky Lines 128 Propagation Chart 128 Advertiser index Lin Green talks home via two meters while skiing on Mt. Snow in Vermont, checking on daughter Sage, being minded by Ken. The 110-mile path is via K1ZJH repeater about 60 miles away. (Where's Wayne, you say Who do you think took the picture ) 73 Magazine is published monthly by 73 Inc., Peterborough, New Hampshire 03458. Subscription rates...

Agmmddy

A page in an old notebook, with a couple of circuits and the words Crystadin and Losev, brought a few memories and forced me to plug in a soldering iron and run a few experiments. Time middle 1920's Place Moscow, Russia Time of the day just after midnight Picture 15 year old ham (later K6BIJ), sleepy, but determined, trying to adjust two cat whiskers on two crystals at the same time, while listening to weird sounds emanating from two earphones. This was Crystadin, a circuit introduced by a...

International Precision Radio Crystals

International Crystals are available from 70 KHz to 160 MHz in a wide variety ot holders. Crystals for use in military equipment can be supplied to meet specifications MIL-C-3098E. (GP) tor General Purpose applications tvdJc. ,or Commercial Standard TYPES (HA) for High Accuracy close temperature tolerance requirements. A single tuned circuit intended for signal conversion in the 3 to 170 MHz range. Harmonics of the OX oscillator are used for injection in the 60 to 170 MHz range. Lo Kit 3 to 20...

Receiver Mc

R-748 TRC-47 single channel AM crystal controlled 110V 60CPS pwr supply Si speaker built in, squelch, r-f gain, dual conversion modern design. Size 19W x 5H x 14D for rack mtg. Supplied with schematic Si hookup info. No conversion required. Exl condition 29.95 Top prices for AN VRC-24, AN TRC-68, AN ARC-51, 52, AN PRC-10A, Collins 618T AN URC-9, AN SRC-20& 21, plus all H.P., Tektronix, and lab grade test equip. Aiso all late model military electronic and radio gear. Write or Call Collect for...

Rm Prices Stymie Prospective Buyers

W5PGG was interested in getting a copy of the RM's on file with the FCC listed on page one of our October issue. He wrote to the FCC and asked for copies of the RM's. No dice. They suggested he get in touch with a company that specializes in that service. Orville wrote to them, giving his list, and got back a quote for the service of S98.46 for the copies of the nine RMs. This cooled him. for enough money to pay my way while I'm in school. Perhaps I can stay for one year and live with an...

Columbia Electronic Sales

7360 Atoll Ave., North Hollywood CA 91609 Tel (213) 875-2970 & 764-9030 C & H SALES WELCOMES 1971 WITH A TREMENDOUS TEST EQPT. SALE. NOW IS THE TIME TO BUY AND SAVE LOTS OF MONEY _ 40 CPS to 200 kc 250,00 195-270 mc 295.00 Sierra H. F. Wave Analyzer Model 158A with two probes .5 to 10 mc 295.00 Model 2102 0 to 50 kc 195.00 John Fluke 407D Power Supply 100.00 Differential Voitmeter 95.00 Differential Voltmeter AC-DC 100.00 Model 5311-1 125.00 Model 7350R-38 125.00 Model 7360C 125.00 Model...

Hp Test Eqpt

H.P. 202A Function Generator 95.00 H.P, 21 9C Pulse Duration Unit 25.00 H.P. 350D Attenuator 75.00 H.P. 355B VHF Attenuator 50.00 H.P, 355C VHF Attenuator 75.00 H.P. 400 HR-VTVM 100.00 H.P. 410B-VTVM 100.00 H.P. 417A VHF Detector 125.00 H.P. 475B Tunable Bolometer Mount 25.00 H.P. 430 CR Microwave Power Meter 35.00 H.P. 428A Clip on DC MA. Meter 150.00 H.P. 525A Plug in 10 to 100 mc 100.00 H.P. 525B Plug in 100 to 220 mc 100.00 H.P. 526C Period Multiplier 100.00 H.P. 522B Counter 100.00 H.P....

General Radio Test Eqpt

Ind 40.00 G.R. 107M Var. Ind. . 40.00 G.R. 1021 P2Sig. Gen. 250-920 mc-with P1 Power Supply 195.00 G.R. 1105A FREQ'. MEASURING EQPT. CONSISTING OF 1106A Freq. Transfer Unit 1106B Freq. Transfer Unit 1107A Interpolation OSC. 110SA Coupling Panel 1109A Comparison Bridge comes complete with Speaker Si housed in 6 ft. Relay Rack 350.00 G.R. 1203B unit P.S 25.00 G.R. 1219A unit Pulse Amp. 25.00 Meter 75.00 G.R. 1750A Sweep Drive 75.00

Ootc Qso Party

The Old Old Timers' Club will hold its 1971 QSO party April 2nd through April 5 th starting and ending at 2300 GMT. Suggested frequencies for-locating the gang are plus or minus the following 3520, 3530, 3820, 3830, 7020, 7030, 7240. 7260, 14279, 14290, 21021, 21030, 21270 and 21280. Participants should avoid any possible interference on any of these frequencies which may be used for net operations. .The FCC figures show that the total number of licensed amateurs dropped 683 during 1970, That...

Turkish Ham Needs Us Sponsor

Seiim Canbeken TA2SC, 19, would like very much to come to the U S and iearn about electronics, ' 'here just isn't any good education in this field available in Turkey and Selim knows what he wants. Amateur radio has not been legal in Turkey for citizens since 1937 so the 150 or so active amateurs have operated quietly and in fear. Radio equipment is almost nonexistent and generally lias to be built from what can be scrounged. There are no radio stores or manufacturers as in the U.S. Even so...

Nterated Circuit Audio Filter

The development of complicated multi-inductor filters and multi-transistor rc filters is culminated in a new type of integrated curcuit audio filter. The filter should have many-applications in amateur radio equipment designs. One item that has been used in innumerable pieces of amateur equipment and accessories over the years is an audio filter. Such filters, particularly if they were used for audio selectivity purposes, could get to be very elaborate and large with multiple section designs....

Sampling Pulses

Fig. 1, Simplified timing diagram fot regenerative repeater. Fig. 1, Simplified timing diagram fot regenerative repeater. Fig. 2. Logic diagram for regenerative repeater. flip-flop is a perfectly timed TTY signal, delayed 11 ms from the input signal, with signal elements corresponding to the condition of the input at the time of sampling see Fig. 1 . After the stop element is sampled, the circuit resets and waits for the next start element. The logic required to perform these functions may be...

Semiconductors

RF amplifier mixer, 4 lead TO-5 case S.40 ea, 6 for S2.00 53-Amperex 2N2089 RF amp. mixer oscillator .35 ea. 12 for 3.00 54-Delco DTS-413 Silicon NPN planar TO-3 case. 400 Vceo 100 mA continuous. Hfe 20 5 v 500 mA. FT 12 MHz. Used as TV vert, output 1.00 ea, 6 S6-RCA 1N3754 Silicon Diode 1.3 A 125 piv. Single ended TO-1 case. Used as biasing diode in power amp base to emitter circuit or general purpose .15 ea, 8 for 1.00 S7 Fairchild FD-100 ultra-high speed...

Erickson Electronics

Ravenswood Ave., Chicago, Illinois 60640 PETITION Iliad by Wayne Qiaon W2NED 1. PXarhoxHjgll. New Hampahir , Tho Fidnl Communication commlaalon hn had eon ld r bl difficulty with ha 27 MHr CI til MM band. Ihauunll of oparito't ai uung thh and tor hobby uurpoaea ntn though ill la WOMar.aO by lha ragulaiion . TnouuoOi man Such band would p-Orida a lapal way lor tha I to camrr urvleala and COUI '' ffa t 11 harwl lt V nt original puipm m Tha drop in th g-owth of KTiea la laflecllng along to...

Jefftronics

Cleveland, Ohio 44109 Blow your mind on our back issue bargain bunch, 30 count 'em assorted we hope back issues, all before 1968, for the incredibly low price of 6 postpaid hardly pays for the postage . These are packed by slave labor to cut costs so please ignore notes calling for help, etc. that may be slipped into the bundles. 73 Gunsmoke, Peterborough NH 03458. Send cash, check or negotiable securities. New high performance 2-meter transceiver SR-C826M Complete as shown with...

Ohm Non Inductive Load Resistor

7 long x 14 diameter ship wt. 1 lb 2.50 CO-AX ANTENNA RELAY - BNC Connectors New packed ship wt. 1 lb 5.00 NEMS CLARK TELEMETRY RECEIVER Model 1412 215 mhz-260mhz ship wt. 75 lb S200.00 NEMS CLARK TELEMETRY RECEIVER Model 1671 175-260 mhz ship wt. 100 1b S2S0.00 TRANSFORMER - 970 volt 200 ma center tapped with 6.3 10A 5v 2A 5 x 5 x 6 115 vac Primary ship wt. 17 lb 7.00 TRANSFORMER - 550 volt 200 ma center tapped with 6,3 10A 5v 2A 5 x 5 x 4 115 vac Primary ship wt. 8 lb S5.50 TRANSFORMER - 30...

Radio

In our rrrablla tociaty today, wa hav hi v f-incrBasing noad for panonat two-way radio communication from moving v hkla gt and In famot roe. whar l r-d Una communication laclliii a or not Ivallabla. Tha primary naM It for thort ranga communlcnloni within t n mllo . Tha co tof oulprraant mjn b h pt iow for th gtoataxt barofit to tha grtttfert.numb Chiron . Th H flexibility of uaa i hlmaall to thii 1 whether he ba In h liar the ortatai that The chlz n may ay vie in all hb c civ Irl a , i hont or...

Vanguard Labs

Ray Grenier Drake

H, 196-23 Jamaica Ay ., Hollli, N.Y. 11423 Ray Grenier, K9KHW, Mail Order Sales Manager at AMATEUR ELECTRONIC SUPPLY, says Operating all bands 160 thru 2 Meters Is a real pleasure with my DRAKE 4 LINE setup. You, too, can eliminate all of that extra gear and mess usually needed for that much frequency coverage. Let me help you go the same route. . . .all the way, as I have done - or just one unit at a time. Visit our store or write me at AMATEUR ELECTRONIC SUPPLY for the best Trade or...

See the Mann

For the best in USED FM communications equipment Two-Way FM Units m Walkies Repeaters Mobile Phone Bases Mobiles Here are some of the great buys at Mann T41GGV 30W 6 12V Vibrator Supply in 10 housing, with acc. . 60 T51GGV 60W 6 12V Vibrator Supply in 15 housing, with acc. . 70 U41GGT 30W 12V T-Power Supply in 10 housing, with acc. 125 U51GGT 60W 12V T-Power Supply in 10 housing, with acc. 145 T43GGV 30W 6 12V Vibrator Supply in 10 housing, with acc. . 99 X53GAD Two Separate 60W Transmitters,...

Co

TS-155 UP Signal generator, 2400 to 3750mhz . IE-19 TEST SET in chest complete with 100-156mhz signal generator, field strength meter, ideal for one who wants a low price VHF tBSt set-up ,,,.,. 18.50 i UPM-6B Transponder test set with probe, FA A approved TS-251 UP Loran test set, used To calibrate all loran navigation equipment 79.00 TS-62 AP Hi-D resonant cavity, 9320-9420mhz, 50 ohm I E-36 test set, used to test VHF SCR 274N eou ipment m TS 419 U, same as H.P. 616A or ARC H-12, SOOmhz to 21...

Wlmd

A number of people have inquired about other types of ICs which might be used. Suppose that you wanted to count up higher in frequency. To do this, you would have to change the time constant of the input shaper by putting in a smaller condenser, and then using higher frequency ICs Say you wanted to read the output of a 7 MHz vfo. Simple. Use Fairchild 926s freq. to 8 MHz as opposed to 2 MHz of the 923 . Make a For those people who are interested in the theory behind digital readouts and...

Info

Model 636NC Brand New Dummy Loads 5012 0-3000 MC Maximum Wattage 600 ONLY S50.00 TS-323 UR FREQ. METER, portable crystal controlled heterodyne-type instrument. PRICE 74.95 Freq. range 20-450mc. With power supply, PRICE 90,00 EXCELLENT CONDITION. SHPT. WT. 35 R509 ARC RECEIVERS freq. range 118-143mc T19 ARC RECEIVERS freq. range 3-4mc. NEW PRICE 12.95

Series Ic Grab

Mix of 7400 series DIP, unmarked untested. Some schematics provided 10 for 1.00 Runs on 115V 60 cycle. We include diagram, diodes, caps, resistors, transformer. Gives you a choice of 6V at 70 amps 12V at 35 amps 24V at 17 amps. Ship wgt. 30 lbs PK-1 16.00 Mfgrs' name withheld but you'll recognize them. Worth over 10 each. Slightly below mfgrs specs but tested OK amp guaranteed. Any SA-1, SQ, SQ-1 or SQ-10 for 2.00 w diagram. Many others on hand, send for list. Brand new Tl plug in solid state...

Mmmms

All items marked are half price until may 31st 1971. LOOKING FOR A CERTAIN MOTOROLA ITEM LET OS KNOW WHAT IT IS. WE MAY HAVE IT Two wire remotes, 2 freq., intercom, tone osc 29.95 T51, 6 12 v, 40-50 MHz 50 watt mobiles 39.95 L44 450 MHz base stations 125.00 D43 2 meter 6 12 v mobiles 30 watt 100.00 TU 588 transistorized pwr supplies w heat sink 40.00 FM Station Monitors, 40-50 MHz F4M24B1C 85.00 Dispatcher power supplies, 12 v NU 169 19.95 450 MHz receiver strips 14.95 U44 BBT T power 12v 450...

Ttl Integrated Circuits

TTL 7400 series T.C.'s need no introduction to the electronics experimenter. They are the latest most frequently used units. Our units are brand new, fully marked and are guaranteed to meet original manufacturers specifications. The low price needs no comment 7400 Quad 2 input nand gate .50 7410 Triple 3 input nand gate 50 7420 Dual 4 input nand gate 50 7430 8 input gate 50 7440 Dual 4 input 7450 Dual 2 wide 2 input expandable 50 7470 J.K. 7472 J.K. master-slave flip-flop 75 7473 Dual J.K....

Hygains Avtwb

Take the wide band, omni-directional performance of Hy-Gain's famous 14AVQ WB, add 80 meter capability plus extra-heavy duty construction-and you have the unrivalled new 18AVT WB. In other words, you have quite an antenna. Automatic switching, five band capability is accomplished through the use of three beefed-up Hy-Q traps featuring large diameter coils that develop an exceptionally favorable L C ratio . Across-the-band performance with just one furnished setting for each band 10 through 40 ....

Eky Video Vision Co

Ceivers and test equipment, where current loads are not likely to vary widely. Transmitters, on the other hand, use choke-input filter circuits more frequently. The differences between the choke-input filter actions and the actions of the capacitor-input filter are best understood by looking at the waveforms which show what happens inside the power suply during a single cycle of ac input. The waveforms for a capacitor-input filter are shown in Fig. 6. Full-wave rectification is assumed...

Collins T-47 Art-13

COLLINS R-648 ARR-41, tunes 190-550khz end 2 to 25mhz, digital readout, 28vdc, easy to convert to 11 5V SOCV, airborne R 390 COLLINS H 388 URR, military version ol the 51J 3, tunes 500khz to 30.5mhz. a favorite 325.00 HAMMARLUND SP-600JX rcvr tunes 540khz-54mhz a pop RTTY CW amp SWLrcvr S295.00 AN URR-13 receiver, tuneable UHf 200-400mhz, popular for UHF horn bands, monitoring military and astronaut frequencies best in UHF S35 00 T-593 TRC-47 VHF AM transmitter, 132t50mhz, Jingle channel, xtal...

M

Score 1 for Autopatch During the past several years, there has been some rather strong protest from various sides against repeaters and autopatches. I am a commercial pilot and carry my HT with me whenever I fly, I'v worked into repeaters across the entire United States and I can't say I can agree with very many of the objections for these two technological devices. However, I have a question for the opponents of this form of progress. What price are the repeaters and auto- things were simple...

Zm

Where applicable, use a more definitive indicator such as OE. OR. OT. etc. Where applicable, use a more definitive indicator such as OE, OR, OT. etc. Diesel motor, electric motor, gasoline engine, synchro, etc. Cable hBnger, clamp, protector, etc. Container, loft, vest, etc. Camera, projector, sens tometer, etc. Where applicable, use a more definitive indicator such as AM. R, T, etc. Non-rotating type such as vibrator pack rectifier, thermoelectric, etc. Rotating power equipment other than...

Hp B Vtvm

HP 430C Microwave Power Meter . . 125.00 HP 430CR Microwave Power Meter . 125.00 HP 5240 Counter 650.00 HP525A Converter 10-100 mc 150.00 HP525B Converter 100 220 mc . . . . 150.00 HP 583C Sweep Ose. 2 4 kmc 500.00 HP 684C Sweep Ose. 4-8 kmc 500.00 HP 211 A Sq. Wave Generator 200.00 HP212A Pulse Generator 250.00 HP-614A Signal Generator 1,000.00 HP-616B Signal Generator 800.00 HP-618B Signal Generator 1,000.00 Measurements 65B Signal Generator 500.00 SG-1A ARN Signal Generator with PP-34S Power...

Fairchild Phelco Rca Motorola

YOU NEED IT -WE HAVE IT RTL or TTL LOGIC UL 900 Buffer UL 914 Gate UL 923 JK Flip-flop MC 790P Dual JK Flip-flop 2.00 10 18.95 MC 890P Dual JK Flip-flop 2.00 10 18.95 MC 789P Hex Inverter MC 724P Quad 2 Input Gate I iiymys MC 780P Decade MC 767P Quad Latch 3.00 MC 9760P Decade 5.00 ONE EACH OF 3 ABOVE 10.50 7400 Quad 2 Input NAND Gate 75 lt - 10 6.95 7404 He Inverter 7473 DuaT JK Flip-flop 1.60 10 14.95 7475 Quad Latch 7490 Decade Counter 2.70 10 25.50 741 Op Amp CA 3035 Linear Amplifier 2.25...

Test Equipment

USED, CHECKED GUARANTEED IN GOOD WORKING CONDITION TEKTRONIX Plug-ins for 530-series scopes. Types B, D, E, K, L.................. 60.00 each FLUKE 801 Differential Voltmeter.....S125.00 FLUKE 101 VAW Meter with 3 shunts. . 125.00 DUMONT 304-A Oscilloscope, 5-inc. . . . 100.00 HEWLETT-PACKARD 524-B Counter, to 10 Mc. Can use plug-in units to count to over 200 Mc. Plug-ins not included............... 400.00 HEWLETT-PACKARD 523-B counter, to 1 Mc. HEWLETT-PACKARD 185- Sampling Scope with 187-B...