Magazine

4 Who's Who in Amateur 8 Stacked Gamma Matched 10 VHF Vacation 2M slot ntftnna made out of aluminum foil. 14 S-Unit For calibrating S-meters and antenna gain. 20 In The Nor for serious amateurs or heart patients. 24 Don't Kilt Your 26 Working DX Without Six Persistance and sneak iness substituted for power. 28 The Short-Vee 10-15-20M, 56' on a leg and it works, 30 The Little 80 10M antenna looks a lot like the Joystick. 32 Easy Tuning of the Multi-element quads can be awfuliy difficult. 36 The...

Staff

Wayne Green W2NSD 1 Kayla Bloom W1EMV Roger Block Nellie Sildar Tim Garfield Mary Andreae Dorothy Gibson Ruth Ring George Griffith John Van Hillo Mike Hill 73 Magazine is published by 73, Inc., Peterborough, N.H. 03458. Sul> scription rate 12.00 for Three years, 6.00 for one year. Second Class Postage paid at Peterborough, New Hampshire, and at additional mailing offices. Printed at Pontiac, Illinois, U. S, Entire contents copyright 1969 by 73, Inc. Postmasters, please send form 3579 to 73...

Bti Amateur Division

Maximun legal input Full loading 8O-IOM Rugged Eimac 3-lOOOZ Dependable operation Easy to load and tune No flattopping with ALC Distinguished console Instant transmit High efficiency circuit Designed for safety Fast band switching Real signal impact A look at the interior. Obviously a simple device to build. SWR indicator is not limited to tuning antenna matching networks- It can be used by anyone who would prefer its simplified SWR readout. If R1 is set to a higher SWR than that actually...

Pzi

Fig. 2, As described in the text, the gain of three dissimilar antennas may each be found although the gain of none of the antennas is known. D, distance between antennas, need not be equaL The only requirement is that all the antennas have the same polarization. does not take into account any other signals being present except the transmitted one in space. At high enough frequencies, this condition is reached with radio transmissions but at lower frequencies an antenna will receive noise...

Info

By laying a straight edge across two known quan tities, the third can be determined. of 90 degrees, the reactances cancel each other, and the circuit is said to be in resonance. he series resonant circuit offers a very low resistance to the flow of alternating current at the resonant frequency, and the parallel resonant circuit offers a very high resistance to the flow of alternating current at the resonant frequency. The frequency of resonance may be found by...

Wazk

makes an audtble ton* to monitor the RF of any CW transmitter from IQMw to 1 Kw (00Kc to lOOOMc, tiling only an 6' pickup antenna. can be self-triggered for cod* practice or the testing of to I id tat* component and circuits. aid* m tuning up testing Rf osciiUtor *rd power circuits. U transistor, 2 diode circuit, spe ak f, tone adjust, AA pencell, test Teads, 81 ant, Cr magnetic base. cabinet it 6 gauge black r clear anodii d aluminum, 3.4 x. 2.3 x 1.2 US made & guaranteed for I year. James...

Bottom View

Lent regulatoi tubes should be used with the required dropping resistor (value depending on voltage). The 017-ART13 pto should not be used with more than 105 volts to minimize harmonic output. Once the power supply is assembled, the pto should be connected and checked by listening for its signal on the low end of the BC band. 2, Next the crystal oscillator should be completed- The only critical parts are the feed back capacitors from cathode to ground and from cathode to grid. The operation of...

Up

35 8.200 mc amp 650 7 700 2.50 f t 43 i - - ' 10 s in tit o' 't m Nn invantar v inq irl vvkornvd G t on our ftitfliiig litt. BOB-FRANK ELECTRONICS So 13Z7r Himburg, Pi 17 05 tim's net. I don't think you would have any trouble in getting divorced people to talk. The QSO would start 1Let me tell you about my case-it's different ' This type o QSO would last for hours and far into the morning. Your mention of missionaries on the ham bands recalls to mind the fact that the Seventh-day Adven-tists...

Wlhg

Will Amateur Radio Win the Technology Race Ham radio is becoming extremely technical, what with SSB, VHF, UHF SHF, Moon-bounce, Pulse, Masers, Lasers, etc. Unless the convictions of most amateur radio operators change drastically, technology may destroy ham radio- As an 18-year old electronics engineering student, I have been observing the more experienced operators above the age of thirty, most of whom have become content to possess their general license and just chew the rag. Few will admit...

Value

500 MFD-200 VDC 1,500 MFD-1 00 VDC 3,500 MFD- 55 VDC 3,500 MFD- 75 VDC 5.000 MFD- 36 VDC 5,500 MFD- 45 VDC 1 1,000 MFD- 19 VDC 1 1,500 MFD- IS VDC 12,500 MFD- 16 VDC 10,000 MFD- 15 VDC 14,000 MFD- 13 VDC 1 5,000 MFD- 12 VDC 15,500 MFD- 10 VDC 1 5,000 MFD- 10 VDC 25,000 MFD- 6 VDC 30,000 MFD- 10 VDC 60,000 MFD- 5 VDC 20,000 MFD- 15 VDC 15,000 MFD- 15 VDC 35,000 MFD- 12 VDC 7,000 MFD- 13 VDC 3,000 MFD- 25 VDC 2,500 MFD- 45 VDC 3,750 MFD- 75 VDC SIZE 2 x4 gt 4 x4 W xA x4T4 x4 x4' j X4K x4K 2 2 2 2...

Motorola Fm Equipment Schematic Digest

91 pages I iW1 x 17 of schematics, crystal information, alignment instructions, service hints and specialized information. 3.95 post paid. HOO Tremont Street Boston, Massachusetts 02120 f I,iB ommand receive, rtiij AMr 9 tube. 2 lj - ensjtivuv o du Vrv knob, liming ranh. technical data Needs power supply A. coin rots other Commands NtW . t. , .J gt 7.50 R21 command receiver 540-1 60 kC gt With kimh .md tuning graph amp tech meal data. OK . 17.95 Rl I Modern Q l 0 550 Kt K, 11. no Jul BranJ nrw...

Gt Transceiver

The greatest break-through in 1969 1 ran see i vers is Galaxy Electronics hot new GT-550, It has all the great qualities of Galaxy engineering, plus a lot of great new features yet is still a compact ll x 12 x6, l'hey call it HOT, Husky and Handsome and you will have to agree The GT-550 lias new Power,. 550 watts SSH, is engineered like u line watch and is a real beauty. Now available with a complete line of handsome matched accessories.

New Books

Written by Abraham Marcus and published by Prentice-Tall, Electronics for Technicians is a sequel to Electricity or Technicians, It describes electronic phenomena in physical terms, rather than mathematical and is extremely well-written, le book is divided into three sections. Section 1 deals with the electron tube- The various types of tubes are discussed in language which almost anyone with any electronic knowledge can easily understand. Section II discusses semiconductor theory and the...

Arcturus Electronics Corp

502-22nd St Union City, N.J. 07017 D pt.M73 Reduces Interference md 4 Htfifi1 or ALL Amateur Transmitterj. Guaranteed for 1000 Watts Pow-Rfceptton Siron tr Com pine er, Light. Neat, Weatherproof, with Qfc ft 12 ohm icrdimc. Sealed resonant For novice 11 cl s radio jiTijriurs EiSimiMies 5 siparaU inlrnn,i wilhL bttjtr jler rmance guaranteed l 5-10 metir bandi. Cojnplete 02 ft S10 lt i5 40-20-1 M0 meter Sintis. 54 ft, T r vkorLI-wide short wave rcceptfcfil S1 amp 95 Send only S3.00 icash, ck, mn...

Miniature Signal Tracer

350 Signal Tracer

This is by far the single most valuable piece of test equipment for servicing receivers and audio equipment. Built in meter for measuring gain of each stage under test. Easy to find weak or defective stages. Output speaker built in or to VTVM or scope. No line cord since it is self powered. Model SE-350 Signal Tracer-ONLY 22.50 Buy DGP Miniature Test Equipment from Your Local Distributor or Order Direct Mail from REDLINE CO. JAFFREY, NH 03452 Please allow a little extra for postage charges....

Prestel Field Strengthmeter

Frequency Range 40 to 230 and 470 to 860 Megahertz. Calibrated outword from 10 to 50,000 Microvolts, Nothinq makes it easier to properly and speedily find the correct place to Install TV, FM and Com munlcation Antennas. You can measure and Hear the signals with this 4 2 volt battery economically powered unit. There is nothing else like it WIRE, WRITE, PHONE COLLECT WE PAY FREIGHT ON ALL PURCHASES WE HAKE 548 Broadway, New York, New York 10012, Phone 212-925-6000

Ls

Coupling coii to transmitter. The average RTTY enthusist will devote long hours and careful planning to come up with the best possible TU. Then in a rush to get the rig on the air will, ail too often, slap a diode shifter on any existing VFO - with less than the desired result. Or, should he decide to shift a crystal he may spend hours grinding the rock to a net frequency only to find his shift shy of the 850 Hz. Not to mention the fact that the net frequency may change about the time...

8jk Lazy H Antenna

Systems, and 4 travelling-wave antennas. Driven arrays include broadside arrays, endfire arrays, and combinations of the two. The Lazy H, ZL Special, 8JK beam, and Franlkin Collinear array are examples of driven arrays, as are most directive BGestation installations. Almost all parasitic arrays are of the endfire type the most common such design is the Yagi antenna. Reflective systems are used primarily in the UHF and higher-frequency regions, and include the big dishes and the corner reflector...

Kemo

There have always been many hams in the military. Since communications are a vital link in the successful maintenance of a proper military establishment, it would be difficult to envision a situation in which there were no reasonably close relationship between the Defense Department and Amateur Radio. In times of crisis, we are expected to furnish a pool of experienced communications personnel, upon which the military can depend. This calls foi some degree of liaison. Some o the high ranking...

Wnjr

General Electric has over 1000 hams, and there are hundreds at RCA, Westinghouse, Bell Telephone and others. Ford Motors has a ham club with over 100 active members. There are amateurs in ail sorts of industrial and commercial institutions. Banks, department stores, railroads, shipping companies, utilities, airlines, mining and smelting companies, steel and copper firms, newspapers, Vice Pres. Eastman Kodak PresM S perry Rand Pres., TMC Systems Reeves Sound Studios, etc. Exec.j Standard Oil...

Industry

SEND ORDER TO 73 MAGAZINE PETERBOROUGH - N.H - 03458 HAMFEST sponsored by Lancaster amp Fairfield County ARC at Derby Downs one mile south of Lancaster, Ohio on BIS Road, Route 793, June 8th. Gigantic Swap Shop. 1.00 registration with prizes every half hour. Main prize drawing. Good food at reasonable prices, WRL's used gear has trial-terms-guarantee KWM1, 299,95 SR34AC, 149.95 HE45B, 79 95 Swan 240, 179.95 Galaxy V, 229,95 B amp W 5100B, 109.95 HX20, 149.95 HX50, 249.95 Ameco R5, 59.95 SX146,...

Antenna Leads

The test system consists ol a simple receiver with a diode, a capacitor, a micro-ammeter, and a variable resistor. recommend aluminum clothesline and some pieces of soft wood. With this equipment almost anyone can embark on a career as an amateur antenna designer and if you fail at that, you can always try writing articles. Rear Connectors for That Imported SWR Bridge One of the best all-around values on today's ham market is the 10 imported SWR bridge. But a shortcoming of these units is...

Books For The Amateur

Advanced amp Extra-Class Amateur License Handbook by Howard S, Pyle, W70E. Provides all the information you need to obtain your advanced-or extra-class license. Makes preparation for these top licenses far easier for present holders of lower licenses. Includes sample questions for each exam 192 pages. 20649, General-Class Amateur License Handbook by Howard S. Pyle, W70E. A complete guide, including typical FCC test questions and answers, to help you prepare for the Technician, Conditional, or...

BAND

5 9 reports to the Eastern half of the J. S. A., 5 8 reports to Germany etc. Conclusion The results shown above are not precise, nor can they be expected to be precise. There are too many unknown factors entering the electrical picture, such as those which required a shortening of the cl JL Ili a in this example, to somewhat less than a half wave length. But the bridge showed us the overall picture and suggested what was required to be done. The on-the-air results show that it was giving us a...

Military Electronics

24 PAGES crammed with Gov't Surplus Electronic Gear-the Biggest Bargain Buys in America It will pay you to SEND 25tf for your copy -Refunded with your First Order BC-G45 TRANSCEIVER, 15 tubes. 43b to 500 Mc. Easily adapted for 2 way voice or code on Ham, Mobile, Teltv vision Experimental and Citizens' Bands, With tubes, less power supply in factory carton. Brand new 16.95 Transceiver, Dynamotor and all accessor les, including mountings. UHF Antenna Assemblies, control box, complete. BRAND NEW...