Vanguard Labs

H Hoi lis, NX 11423 giving 16254. Then (162540). Subtract leaving 146.186 add a zero to 16254 16254 from 162540, , Very quick. You can't beat this offer Art Brothers W7NVY, president of the Silver Beehive Telephone Company in Grouse Creek, Utah 84313, has offered two 88-mH toroid telephone loading t oils of the type used in many RTTY converters and audio filters free to those who write him and request them. Include 25c for postage and handling, and your QSL card*...

Hcj Electronics

E* 6904 Spraque Ave Spokane, Wash. 99206 FT-243 HOLDERS, FUNDAMENTAL FREQUENCIES.) SO meters 3705-3745 kc. 40 meters 7155-7195 kc. 15 meters 7033 7083 kc. Ariel postal)a por crystal E> c first class, iQc airmail. Spcciiy frequency do si red 3 rid nearest available will he sent. Other frequencies in stock. Free list. Dealer and club inquiries invited. Satisfaction guaranteed, NAT STINNETTE, Box Q, UmatiHa Ha, 32784 J Squolo a fell half wove, horizontally polarized, omni-direcilonai ASQ-2 2...

Info

MF- Not very professional, but quite effective. Two 8000 mV units at 55 volts each from Harry s for 2.50 apiece would work even better in parallel. you use odd values in series be sure to shunt them with a 3.3k, s watt, resistor or at least 100 ohms per volt of supply voltage to equalize the voltage drop across the capacitors. Construction is straightforward and wiring noncritical. The front panel should be attached to the chassis first and then the switch and pilot light IjoIcs drilled. Locate...

New Products

Shielding assures minimum radiated leakage, rhe power supply is regulated for maximum output stability. The KG-686 kit is furnished with a BNC output jack, mated terminated cable, solder, detailed assembly manual and operators manual everything vou need. Available for 95.00 from Allied Radia Corporation, 100 N. W estern Avenue, Chicago, Illinois 60680, Knight-Kit Solid-State RF Signal Generator If you have been struggling with an old tube-type signal generator or using a unit that is poorly...

South Bascom Avenue

Northern California's Most Complete Ham Store of output, distortion is low, sensitivity for 1 W output is only 75 mVf gain is 72 dli input impedance 40 kf and efficiency is about It requires a heat sink which is attached to a small tab sticking out of the end of the device. External circuitry isn't very complicated, either. Now, about that miniature receiver you were going to build . . , The death of Ewell Carter WA6ZAIJ, originator and director of Aries, lias caused severe problems for the...

Herbert W Gordon Company

WOODCHUCK HILL, HARVARD, MASS. 01451 Have you found a simple new circuit, or new semiconductor or other component, that has been useful in your building I here are plenty of hams who would like to find out about it. Why not send in a short note for this column and we'll publicize it and make if available io all the other experimenters who read 73. We're also looking for technical comments on 73 articles corrections, modifications, or compliments and newly available surplus, technical nets and...

Tose Clamp

Construction of a typical element, showing the adjustable end sections, Fig. 3. Construction of a typical element, showing the adjustable end sections, mension of the plate and fastened with small U-bolts. On my own model I used angle iron instead and fastened the elements onto the iron with stainless steel bolts. Be sure you use nothing but rust-proof hardware on the beam. There isn t much required, and the small cost is well worthwhile if and when you try to take it apart again, Fig,...

Ogajd

L Typical alternator schematic showing wye-connected stator windings the stator midpoint is brought out to a terminal only on Ford (Autolite) units. While there are a number of alternator regulator systems, some characteristics are common to all of the recent models. To begin with, all of the alternators are designed to be mounted on the engine block they are belt driven. The alternator pulley is about 3 inches in diameter while the driving (crankshaft) pulley is not less than 6 inches in...

Sunday Telephone Service Am Pm

If Price 2 per 25 words for non-commercial ods 5 per 25 words for business ventures. No display ads or agency discount* Include your check with order., ir Type copy. Phrase and punctuate exactly as you wish It to appear. No aINcapital ads. 4r We will be the judge of suitability of ads. Our re* sponslbflity for errors extends only to printing a correct ad In a later Issue. if For SI extra we can malntaie a reply box for you. if We coeeot check Into each advertiser, so Caveat Emptor . . SELL Col...

Ham

Jenkintown, Pa. 19046 Phone 215-887-7350 Edgar Wagner G3BfD 5 Feroncroft Avenue London, 3, England The Front-to-Back Ratio of an Automobile Have you ever checked the antenna pattern of your mobile antenna We are, of course accustomed to thinking in terms of the back-to-frout ratio of beams, but how about the directional properties of the automobile in mobile operation Some time ago I did some work on this subject willi a view to learning something about the effect of different positions for an...

Epsilon Records

206 East Front StrMt Floren , Colorado HEATHKIT KS-1 kilowatt power supply wanted. Send price and condition. Sell or trade new Clegg 99'er. 85 gt 00. Don Johnson, KtiMIM, 76 LaVerne Ave., Ventura, California, 93003, phone 805-642-5338, BACK dated comics, magazines, pocket novels from a dozen to a truck load. Write for prices, Georges Enterprises, 192 Main St, Moosup. Conn. 06354, DRAKE 2B, 2AC 2BQ with manual- Price S1S5.00 Ship COD. WB4CDA, Lee Herrington, 313 63rd Ave. North, Myrtle Beach,...

Space Age Keyer

Planar epitaxial iniegrofed circuits for reliability, No tubes- No separate transistors Precision feother-touch key bui Mn. Fully digital Dot-dash ratio always per- feet. No polarity problems Floating contacts switch 300-V 100-ma. Rugged solid construction will not walk Send Q5L or postcard for free brochure. Well OM5 you say that you really have your shack cleaned up , . after all these years Yes, I suppose it does look pretty good from the operating position, but how neat are things behind...

Wasam

Jim Fellows WA3AJD 7517 Creightoll Drive College Park, Maryland 20741 Did you ever consider trying some mobile operation, only to drop the idea like a hot 813 for fear of marring your car with a permanent antenna installation Worry no longer, for here is a temporary antenna mount which in no way harms the vehicle it is fastened to and yet is as strong as any bumper-mount. The X-mount was born of necessity I wanted to share in the fun ol mobile operation, and yet. there were orders that no holes...

Wjw

Coil Nomograph

Where Po is the output power, Vck is the voltage between collector and emitter, and Ic is the collector current, In practice a value in the range from 1500 to 5000 ohms is emitter capacitor in a transistor Colpitts oscillator circuit capacitance Cr is known, in this caser capacitance of 355 pF requires a collector-omitter The onK other consideration is what Iran- sistor to use- Theoretically, the oscillator transistor only requires a gain of one or unity, but in practical circuits the gain must...

Canada

Canada If you live outside of a distributor area order directly from the factory. Send for our new Amateur Ractio Catalog. Walter Anderson VE3AAZ 146 Oeloraino Avenue Toronto 12, Ontario Canada It is one of those minor ironies that during . the past ten or fifteen years, while the single-ended audio amplifier has almost completely given way to push-pull, exactly the reverse has occurred in respect to rf amplifiers. This is even more surprising when one remarks...

Tristao Trl-80 Tower Raising Fixture

Queens Village, 11427 That's right, Gel your FCC commercial operator's license, and then work, at qood pay, in your hobby field radio and e ectronics. We prepare you by correspondence, under our 'ae your license or your money bact1' warranty. Get full details In our free FCC license Course Brochure. Write Grantham School of Electronics, Dept. R, 1505 N. Western AveM Hollywood, Calif. 9002T New Design, Light Weight, Free Standing Crank up Towers Safely supports most TRf-BAND...

All Coil Tub Img Silverplated

Be the load to the driver and this is nowhere near the value of 3 . To be blunt, there would be a very high SWR on the driver -to-linear transmission line with consequent difficulty in getting power out of the driver. As an additional complication, unless the exciter and linear are bolted together, these various impedances are transformed differently depending on whether one is considering the direction exciter to linear or linear to exciter. Not only that, these transformations will be...

OUTPUT

Fig. 3, Block diagram of the VHF man's calibrator. Fig 4. Divider section uses integrated circuits to a I MHz crystal. The unmarked resistor in the I struction job as well as to reduce the cost. his two-meter calibrator offers a choice of calibration modes 144 MHz alone, 144 MHz it 1 MHz, 144 MHz 100 kHz, or 144 MHz t0 kHz, The mode-switching allows one to go from a rough 1 MHz interval frequency check to a 100 kHz interval check, and finally, to a 0 kHz interval check. The system is described...

Oscillator

Fig. 2 Layout of the two circuit boards used in the case, the circuit coufd be easily adapted to one dub project. St can be seen from the photograph that the meter amplifier and audio oscillator are built on separate boards. This is due to the fact that I built several different amplifiers the layout would look neater ii they were on the same board. Positioning of the rf oscillator and capacitor as shown in the photograph is recommended, but the placement of other parts is not critical....

Hna

A tuned-base oscillator with feedback from the collector winding. A better impedance match to the base of the transistor may be obtained by using the tapped inductor as shown in B. Fig. 21. A tuned-base oscillator with feedback from the collector winding. A better impedance match to the base of the transistor may be obtained by using the tapped inductor as shown in B. for example, a series LC combination is inserted in both the base and collector leads, which together form the...

Inductance

Nomograph for determining the resonant frequency of tuned circuits. It may afso be used to find the value of capacitance which will resonate at a given frequency with a given coif, or vise versa. A ruler it laid across the two known quantities and the third may be easily found In the case illustrated, 42 fiH resonates at 3.5 MHz with a 50 pF capacitor. ing and the smallest variation in gain. The common-base circuit has reduced stability because of the large input signal power required...

Ocommon

flops io replace the MC790P RTL IC's which are Fig. 6. Divider circuitry using HEP 5S8 J-K flip tion in frequency . Because we are now only interested in harmonies of the modulation frequency that are of relatively low order, the rectangular wave does not have to have a nanosecond rise or fall time. The modulation is not of the linear sort that hams usually encounter, since the rectangular wave essentially turns the signal off and on. The circuit diagram is shown in Fig- 4. Note the use of...

Navy Tcs Receiver Am

1.5 MC to 12 MC In two 2 gt htinA Variable freq. oacHIntor A rryml control on four preset channel fn the lt gt nliro fre . rtinpe. Audio output 1.5 tvuris into 500 ohm load tuber f.ESK7 UF A., 12RA7 converter. 2 12SKT IF A., 12SQ7 detector UFn, 13 A asritlsror, ISA audio Amp, 456 KC IF Frwj. Kirfie vernier A siiln dial, audio gain, AYC, BFO ind 1I cjutrols on Ito from panel. Voltages r 'iuired VDC A ap rox. 120 VDC 10U AtA, Size 11 ll1 95 i 13 . Wt, 37 lbs___________________USED 1,5 MC to 12 MC...

Wbpd

Delivers uncompromised full-sized performance on 10, 15 amp 20 meters Exclusive time-proven Beta Match T ry as you may, you just won't find another three-element tribander for 10, 15 and 20 meters that will even begin to compare with Hy-Garn's Model TH3Mk2, Some say its the individually tuned, large diameter Hy-Q traps that make the difference by providing tull-sized performance on each band. Others say it's the spacing of the elements on the 14 foot boom. Still others claim it's the ex...

Wtoe

Next Month A discussion of proper opera-Ling techniques and related tricks of the trade, recommendations for suitable magazines and Other literature, and a general summing up, embarking Judy and Joe on the road to the General Glass and firing Tom with increased enthusiasm to become a novice and catch up with the kids. u semitive brood band It F fiotector gives udibte ton signal in th pretence of any RF field from lOruw to 1 kw and lOOkc to TOOOmc a CW monitor with poiitiv H f 5witch u t only...

Summer Bonus Special

Free MaUhing AC Siippfy with the Following Rigs Galaxy V Mit 11 420.00 Hum-M w c On.OO Drake TE-4 609.95 ITy-Oaln 204BA. 100.no Swan 500 4 J5.00 Hy-duln 1S TT ____lSri.Ol SwEi t 3 0 420.00 Mosloy rinsslc _____ 1U9.0Q B4-A T4-X ____ 799.90 Turner 454X Mike . 17,00 1629 S. Kentucky Ave., Evansvil e. Indiana 47713 Bill Dgg WA9RM0 Oave Clark WA9RFK Now you can get a perfect match for Hy Gain two-meter models 23, 23 and 2J5 This ti an L-match arrangement that gives LOB to 1.00 SWR at the antenna....

Estes Engineering Co I

Gardena, Calif. 90249 3 band eico 753 sideband kit at a special low, low price One thing I hate is the use of super 64 words tis a means of attracting attention W hen you have used up all nf the extravagant phrases, what is left to describe a truly good deal Once in a long while, however, a value tloes cojiie along which is relatively outstanding and which causes me some concern because don't want to turn my principles around in the enthusiasm which I rarely feel. I am...

Intolerance

Would it he vrotig to say that some of the complaints in amateur radio represent intolerance a mild form of the same disease in religion, race and politics This shuwH up in discussions of GMT, Herts, license classes, operating modes activities . , What amateur has earned the authority to tell all others they must use GMT in log-keeping if they want to bo good operators DX'ers are able to think in terms of DX, but casual operators cannot and need not. liut, it is incumbent on the casual man to...

Clapp Oscillator

L 10- TURNS NO. 26 0 J.WMILLER 4500 SLUG TUNED FORM. TAP -3 TUfMS . FROM---- Inductor Li is the rest of the coil '7 turns. The completed circuit is shown in Fig. 18. Like the Colpitis circuit, this oscillator took off as soon as the nine-volt supply was connected. The desired operating condition was very close to that required Vc of 7.2 volts and Ic equaled 1.8 mA, The output voltage, at the collector, was 3.8 volts peak to peak and the timing range was almost identical to the Colpitis circuit...

Section

MODULATION IWPLfT FftOW HEP DiVlOEft Fig. fO, Modulated amplifier for use with the HEP divider section. This circuit replaces the last HEP 55 stage in Fig, 9. when HEP IC's are used Fig. II Construction of the calibrator illustrated schematically in Fig. 4, Motorola MC790P dual RTL J-K ftip-ilops are used In the divider section. MODULATION IWPLfT FftOW HEP DiVlOEft Fig. fO, Modulated amplifier for use with the HEP divider section. This circuit replaces the last HEP 55 stage in Fig, 9. when HEP...

Waajd

The X-mount is secured to the car with suction cups, gutter clips and straps as shown here. The X-mount is secured to the car with suction cups, gutter clips and straps as shown here. Most Technically-Perfected, Finest Communication Arrays in the World 1 Precision-Tuned-Matched and Balun Fed for Balanced-Pattern to assure TOP-MAN-O N-THE-FREQUENCY Results I. V. KITS and ROTATOR SYSTEMS Enjoy, World renown TELREX performance, value and durability Send for PLG7 tech. data and pricing catalog...