Squelch For Your Tunaverter

Noise free monitoring with adj. electronic squelch No wires to Radio or Converter Just plug in coax For alf 1500 kc outputs. 9 or 12V. 1 x4x2. 1 7.50ppd. Mobile Battery Eliminator,12Vto9V 4.95ppd. Crystal Controlled models available 1 & 2 channels with or without Squelch 26 250mcs. -12 volt neg. grd. 19.95 to 44-95. Write for details Coupiing Loop 8i Ext. Antenna for use with home and Transistor Radios 3.95ppd. Crystals State Exact Listening Freq. S5.10ppd. Order from AIR MAl L add .85 ea...

Input

There are two main types of rectifiers in use today. These are germanium and silicon. These two are very similar in outside structure, however, their electrical characteristics vary greatly. A germanium rectifier can handle up to about 250 ma of current at 85 C. Above these specifications the crystal lattice burns out. For higher power and temperature, a silicon rectifier is used. This is similar in construction to the germanium rectifier except that a crystal of silicon alloyed with aluminum...

Accessory Socket

Schematic diagram for modifying the NC-300 for improved SSB reception. Fig. 1. Schematic diagram for modifying the NC-300 for improved SSB reception. resistance is over a megohm, in order that a long time constant can be obtained more easily. The actual charge time depends on the value of the 470 pF capacitor and the cathode resistor, but the 1 mF capacitor can be charged in less than 30 milliseconds without loading that last tuned circuit any more than it is already. The one-second...

Variable Disc Trimmer

Miniature ceramic variable trimmer capacitor. Piston type tuning, size .375 diam, .275 deep. Printed circuit mount. Amateur net on this is 1.68 each. Our price only 25i each or 24 for 5.00. All are brand new. State size, may be assorted if you wish. N300 2.5-11 pf NPO 5.5-18 pf N650 9-35 pf Military surplus made by HUGHES for the AF. Condition appears excellent due ta being enclosed in air tight case with terminations on plug connections. 134 read write heads, 12 heads phase adjustable timing....

Peterborough Nh

If Price 2 per 25 words for non-commercial ads S10 per 25 words for business ventures. No display ads or agency discount. Include your check with order. if Price 2 per 25 words for non-commercial ads S10 per 25 words for business ventures. No display ads or agency discount. Include your check with order. Deadline for ads Is the 1st of the month two months prior to publication. Far example January 1st is the. deadline for the March issue which will be mailed on the 10th of February. ir Type...

Ham Television

The Amateur Television Anthology is a collection of the technical and construction articles from the ATV Experimenter, edited by W0KYQ. If you're interested in ATV, this is the book for you. ft covers the gamut from the simple to the complex in amateur television equipment. 3 MILITARY SURPLUS TV EQUIPMENT by W4WKM is a necessity to the surplus-scrounging ATV addict. CW by W6SFM explains code and how to learn it. CUMULATIVE INDEX lists all the artides in 73 up through December 1966. Please send...

Box Florham Park Nj

TO VOX OPLAY POT ft FSIR tSEETEXTj Fig. 1, Foot switch control for VOX delay. TO VOX OPLAY POT ft FSIR tSEETEXTj Fig. 1, Foot switch control for VOX delay. The particular foot switch used here allowed plenty of room inside to mount the capacitor, and a zip cord was run from the switch to one of the spare jacks on the rear of the 400. When you want the extra delay, just press down on the foot switch. Releasing it will instantly bring back the original vox delay time as set by the internal...

Preamp

30 db compression range Low-noise FET input stage a 5-transistor and 1-diode circuit Adjustable input and output levels Printed circuit construction with easy-to-foliow instructions h 3-way jacks tor PTT operation Easily installed in mike line Other Kits Audio Amplifiers Power Supplies Test Equipment Treasure Locators and many others FREE Data sheets with circuit descriptive, diagram, and specifications lor at kits. P.O. Box 327 Upland, California 91786 Phone 714-985-1540 Stanley Sears, W2PQG...

Arcturus Electronics Corp

502.22nd Si., HflIm City, M.J. 67087 Bapit. amp m Phufle 261-LJfi lt 3-5560 OHIO VALLEY 6 meter phone net 50.350 every Sunday. 2000 EDT, WA8WIW, NCS Sciotoville, Ohio. Traffic and Rag Chewers Welcome. FIND OUT about the New Greene Balun. Read all the details on page 59 of this issue. Greene Balun, Warfield, R.I. o2S80 WANTED TECHNICAL material. Corp model XFK freq. shift exciter for Tmc model GPT 750-also TMC single sideband exciter, model SBE for GPT 750 amp manuals plus 18 to 30 foot...

I

Complete set up of tuner and SWFi bridge. capacitors shown in this tuner will handle the maximum legal power on any mode, but for lower powered rigs they can be much smaller, as long as the actual capacitance is the required value. Tune-up is very simple. Connect the rig as shown in Fig. 3 and feed a little power into the coax line. Resonate the rig's plate circuit, set the SWR bridge to Forward, and adjust it to a maximum reading on the meter. Then switch the meter to Reflected and...

At Leading Ham Distributors

C. 27608 Darrel1 Thorpe 3110 N. 83 Street Scotisdale, Arizona S5257 If you have been disappointed with paralleling rf power transistors in an attempt to get more power output the magic T could be the answer to some of your problems. Paralleling transistors in rf power amplifiers quite often does not yield the expected result that is, double the power output. Unless the transistors are closely matched, one transistor will usually hog the drive power while the other s...

Info

A Next higher frequency may be useful this period B Difficult current this period The addition of a speech compressor to your rig is a worthwhile project. A speech compressor will not only increase your talk power but also reduce flat topping. The simple circuit described here uses two Motorola HEP 801 Field Effect Transistors. The entire unit can be built for approximately S15 or less, depending on the size of your junk box. Features The compressor has an overall gain of unity. Therefore, the...

Letters

There were several omissions in the schematics of the Six Meter KW Linear in the July issue. The most important are as follows Page 21. 1. Coil data not given should be 3 or 4 turns of 1 8 copper tubing, 1 diameter, spaced to resonate with the chosen capacitor. 2. There should be a connector in series with one lead of Kl-this goes to the N. O. contacts of the exciter PTT relay. 4. Cathode pins 2 and 4 should be grounded in addition to pins 6 and 8. Page 23. 1. Note 4 should read transient...

Fone

Terman High Efficiency Grid Modulation

Nielsen, DL5KS Paquet Strass 46, C-3 6 Frankfurt am Main, Germany In the past few years there has been a large interest in the Taylor modulation system, as well as other high efficiency types of modulation. When the first article was written, I became interested in this system. As a result of this interest I did some research and letter writing and would like to pass on the information I have gained. To begin with, R. E. Taylor made a fascinating discovery and introduced his form of...

Net Antennas

For a number of years Hornet Antenna Products of Duncan, Oklahoma has been manufacturing a line of high quality, high performance antennas for the amateur bands as well as for other services. These antennas have been designed and manufactured by Jack Guest, W5AJZ, president of the Hornet company. Probably the best known of his products is the famous Hornet Tribander, made in both 3 and 4 element models and making use of Jack's patented, extremely rugged and efficient frequency dividers, or...

New Books

This hard cover book, written by Bert Simon, W2UUN, has been prepared with the aid of FCC. It covers every question which may be encountered on every amateur test from Novice to Extra. The questions are presented in the form you find on the actual exam. In addition to the question answer sections, the book goes into detail on learning code, the requirements for each class of license, details on how to fill out the form 610, and the examination schedule for the various FCC offices. There is also...

International Crystal Bax-1 Schematic Or Circuit

Wayne Green, W2NSD 1 Ralph race, Jr., WA1GEK Kayla Blook, W1EMV Production Roger Block Phil Price Nellie Sildar Jeff Barsanti JaneTracey Carol Ring 73 Magazine- is published by 73. inc., Peterborough, N.H. 03458 Subscription rate 12 00 for Three years, S6 00 for one sear Second Class Postage paid at Peter borough. New Hampshire. afliJ al addmoiui nailing offices Printed al Puntuc. Illinois. t -v Entire contents copyright 1969 by 7 . Irw PoitiTiiUcr p1e lt tend form to 73 mifi iw. Peierborotish....

Murch Electronics

MAINE 04634 See your distributor or order direcf. such as the Bikini shock wave was that travelled at many Mach numbers. With these smoke rings, the mechanism of the ring, its slowing down in frequency rotation as it travelled, the rotation of the smoke particles following the wave motion around the doughnut shaped ring, their rotational phase-change of 360 degrees around the ring, and their generation by the round exit hole of the box could be seen by the eye. Each particle rotated,...

Pioneer Division

Cleveland, Ohio 44103 PIONEER-STANDARD ELECTRONICS, INC. SREPCO ELECTRONICS DIVISION Diode'Stack Poiver Supplies-The Easy Way Many amateurs wish to have quick-start transmitters with reduced heat during standby periods. This leads to thought of the possibility of replacing rectifier tubes with diodes in high-voltage power supplies. The first approach generally is to look for a hatful of 800-volt or 1,000-voIt diodes with a current rating somewhere between 750 ma and 3...

International

OKLA. 73102 If you can afford a nice beam, complete with tower, rotator, coax, and all that sort of stuff, then no doubt you can get on 15 meters and enjoy all the DX you want. This article is probably not for you. But if you happen to be a Novice with limited funds or a family man who can't afford a major installation, then maybe you should read on a few minutes and see if you have found a solution to your problem with a very simple antenna that will take a back seat to...

Henry Radio Stores

11240 W. oivmpic, L.A., Calif. 90064 931 N. Euclid, Anaheim, Calif. 92801 makes possible operation of the phase shift oscillator illustrated in Fig. 2. In practice, it works out that there is usually somewhat less than ninety degrees of shift. That is the reason three capacitors are required to sustain oscillation in the circuit of Fig. 2. capacitors are most frequently used in this application. The coupling capacitor becomes a grid leak when rf is supplied from VI and no bias is placed on V2....

Douglas Electronics

1118 Sputh Staples Corpus Christi, Texas 7S404 voltage off the respective elements. They operate in slightly different manners. When V3 conducts, the top of the cathod resistor, Rc, becomes more positive with respect to ground. Some of the electrons coming up thru the resistor leave the stream and flow into the positive plate of the capacitor. At the same time some flow out of the negative plate and up thru the resistor. When there is a decrease in the positive voltage on the top of Rc, some...