Radio Amateur 08-1979

Look At The Signal Enhancer

In the fifties and sixties, the best way to improve receiver selectivity at tow cost was to add one of the outboard devices popular then, such as a Q-multi-plier which worked on the set's t-f stages or a war surplus radio range filter which was inserted in the set s headphone lead Both methods left a lot to be desired. It seems that suddenly hams have discovered that the easi est and in some ways, most cost-effective way of improving receiver selectivity is to add an outboard audio fitter The...

Mrf901 Oscillator

1979 Ham Radios

Shown in I ig. 2 a is representative of the MDS receive system as described m this construction article. This system consists of a mixer, voltage controlled local oscillator and i-f amplifier located at the antenna, and the com bination power supply tuning unit, located at the TV set. The RG-59 U feed line then performs the dual purpose of carrying the i-f signal down the line to the TV and carrying the power supply tuning voltage up the line to the converter. This results in a nice, cheap, and...

Yaesu Cpu-2500r Reviews

1979 Ham Radios

The FT-127RA, FT-227RB and FT-627RA, FM transceivers, allow scanning and expanded memory coverage for the demanding VHF FM operator. All feature up down scanning capability with control from the microphone the scanner wil also search for a busy or clear channet. Four memory channels are available two for simplex, three for repeater channels,one for a split of up to 4 MHz. Other performance features are similar to those of the renowned FT-227R. OPTIONAL EQUIPMENT Keyboard Microphone YM-22 for...

Amateur Television In A Nutshell

Sooner or later every ham gets the urge to try something new and different. For some this means a better rig, The more adventuresome types may want to try a new mode. Fastscan television is one such opportunity. Activity starts at 432 MHz and is even found In the microwave bands. Until recently, there has been no universally good source of information for the beginner. This void Is partially filled by the book, Amateur Television in a Nutsheil Everything you need to know to build or operate...

The Stickler

Fl+ WPM CT7306 This is the practice tape for the Novlcr and Technician li censes, it is mad* up of one solid hew ol 13 + WPM -CT7 3 T 3 Code again, at a brisk 13 per so you wt ease when you sll down In front of Ihe steely-eyed government Inspector and he starts sending you plain language 11 only 13 per. You need this extra margin to overcome the panic which is universal in the test situations When you ve spent your money and time to lake Ihe Jest, you'd thank leavens you hadth-3 back breaking...

Mv Communications Specialists

CA 92667 m(714)998-3021 Aug 25-26 All Asian DX contest CW Sept 8* DAFG Short Contest VHF Sept 9* DAFG Short Contest SW Sept 15-16 Scandinavian Activity CW Sept 15-17 Washington State QSO Party Sept 22-23 Scandinavian Activity Phone Sept 29*30 Delta QSO Party Sept 30-Oct 1 Fall Classic Radio Exchange Oct 20-21 ARRL CD Party Phone Nov 17 18 ARRL Sweepstakes Phone Nov 25* DAFG Short Contest VHF Robert Baker WB2GFE 15 Windsor Dr. Area NJ 08004 DAFG 10 METER CONTEST...

Output Range

R75A Kit for mon ior or -veather Satellite ser xe -60dS at 30 KHi. , 369 95 R75B Kil lor norma) ntilm service -60dB al 17KHz. -80dBat 25 KHz 74.95 R75C Kit for repeater service -6GdB at 14 KHz, -SOdBat 22 KHi 564.95 R75D KJt tor split channel operation Uses e pole crystaf filter -GfldB at t 9 KHz. -100dS 15 KHz,., 99.95 Specify bandM 0MP 0MH 2 M+of220 M H z. May a (so be u sed on adjacent commercial bands, Use 2M version for 137MHz WX satellite HAMTRONICS SIX CHANNEL VHF & UHF FM RECEIVERS...

How To Disconnect Alc In A Ft 901 Radio

If you would tike smoother ALC action or if you've been concerned about meter readings in the green part of the ALC scale , this simple modification will ease your mind and produce very good results. Remove the 901's bottom cover and locate the socket for board PB1703, Connect a 68k, VS-Watt resistor between the ground and pin 16 of this socket, then bypass the resistor with a 2.2-uF tantalum capacitor. This is a good time to tweak dot-dash ratios on the Curtis Keyer, if desired. The keyer's PC...

Technical Excellence

Ff you demand the finest, no ami promise technology, you need the FSK 1000 demodulator J Can't be outcopied because i i a design compute c .uK partsr modern tethr*ofogy offer fandline copy over radio circuits. ff you demand the finest, no ami promise technology, you need the FSK 1000 demodulator J Can't be outcopied because i i a design compute c .uK partsr modern tethr*ofogy offer fandline copy over radio circuits. Stops QRM with selet lable 55 or I 00 Hz , fillers and two tone iimiterfess...

Heard On The Band

1979 Ham Radios

The OE6XG A group ran off some 13,800 contacts from Abu Ail despite generator problems. QSL to WA3HUP with SASE. etc. Financial contributions lo help offset the several thousand dollars spent by each member of the group would be appreciated, 3B8CF, 3B8CD, and 3B8DA all hold licenses for 3B6, Agalega, and visit the island regularly to maintain the radar and weather-monitoring equipment. While we're in the area, 5R8AN has been active Mondays and Thursdays from 1900Z VK9NI on Norfolk Island runs a...

Vertical Antennas

* Wide band performance m New ty-Q 3raps e f-SLOpaftirg auTomanc & ar.o s* - re 'r g je.Tica antenna Omrn-iliirecl orAi certo mance Favorable Li C ralto Higfi O True * -esananctofi all oands Lo jng c j-i-ti to- jaitem ace s aggeo seamfe- '-aiummum construclion. 12 doubie-grfp mast bracket FuO circumference compress an at tubing 01n-ls We< ght ModeL iBAVT W6 Automatic band switching nee d-up Hy-Q liap . t-rn I at1- -matte switching. 5 frand capabthr, Favor-at 6 L C fatso Top loading ccjH...

Great Balloon Race

About ten years ago, the famed Fifth Dimension vocal group had a miltion-plus-selting record titled iJUp, UpT and Awayr It was a dream song it told of sailing freely through the air, free of the earthly bonds that shackle mankind to his oh-so-hum-drum existence. It was a song that any dreamer could relate to. It has stayed with me ever since There are balloons of one's dreams and then there are the real kindt the ones filled with helium or just hot air (no pun intended) that do indeed lift man...

A N Alog Output

Fig. 4, Block diagram of a 32-channel analog multiplexer using 16-channel multiplexer chips. A typical example is the 32-channel multiplexer circuit shown in Fig. 4. In this example, a Siliconix DG506 multiplexer is used. Note the use of the enable input at pin 18, This input allows us to switch be tween the two multiplexers by enabling one while disabling the other. With the aid of such an enable input and additional decoder circuits, such a multiplexer scheme can be expanded almost...

Yaesu Ft Dm

Check Hie others then get our pricer Synthesized Handi-Tafkie, 2 Watts In Stock Now CALL NOW FOR OUR PRICE Synthesized Handi-Tafkie, 2 Watts In Stock Now CALL NOW FOR OUR PRICE We have the New Dentron AF-1A Audio Processor, Dentron Antenna Tuners, Antennas and SWR Meters. + CLIPPERTON L -MLA 2500 B * DTR 2000L

High Pass I Filter

The filters must separate the tones (which are input at approximately equal amplitudes, remember) by at least 33 dB (38 dB in the first-run engineering prototype chips). 33 dB is a voltage ratio of 45 to 1. Roughly, if the high tone is 1 volt rms, the low tone on the high input must be less than 20 millivolts rms. The prefilter block diagram is shown in Fig. 2. The major filtering is done using active audio filters in a crossover filter. The crossover point was chosen at...

Hal Buffalo Ny

New device opens up the world of Very Low Frequency radio. Gives reception of the 1750 meter band at 160-190 KHz where transmitters of one watt power can be operated without FCC license. Also covers the navigation radiobeacon band, standard frequency broadcasts, ship-to-shore communications, and the European low frequency broadcast band. The converter moves all these signals to the 80 meter amateur band where they can be tuned In on an ordinary shortwave receiver. The converter fs simple to...

Pc Electronics

For Kenwood TR 7400, Midland 13-510, Yaesu 227R, or KDK FM-144 At your Ham Radio Dealer or Call or Write ciis TTTTTl COMMUNICATIONS I ( If S I ELECTRONICS J SPECIALTIES mc* 399 W. Fairbanks Ave,, Winter Park, Fla 327B9 Scan m few channelt or all BOO - for example * you can program CES Model 800 to scan Repeater and Simplex Channels or all 2 Meter Bands - Other features include instantaneous Addition or Deletion of Channels Scan Resume delay assures hearing return calls * Resume and Hold...

Heavyduty Replacement Transformers

Morse radioteletype reader & speed display Kantronics Field Day morse code teletype reader reads code signals right off the air. Its powerful microcomputer system picks out signals, computes their speed and even reads sloppy copy up to 80 words per minute. The Field Day is simple to use. You plug it into your station receiver just as you would a set of headphones Code arid teletype conversations are converted from dots and dashes to standard alphanumerical text. The text advances from right...

In the Northwest

ATLAS ICOM KENWOOD YAESU Call 206-364 8300 to place your order. We will pay for call when order is shipped. 17550 15th Ave. N.E. Seattle WA 98155 (206) 364-8300 Other locations (Walk-in customers only) Betlevue 120G1 N E. 12th * Everett 4610 Evergreen Way Open Mon. thru Sat.

The Auto Radiophone

THE j re eiii i au* ci fsdii 'clsphAivf ,, im, nL h i . . I i -I I . in IT, iir in ,IIIII .mi -iL'. Ii I i 1-1 LlK.nl r . I L- 1 11 l. l .I'.l.'i h. i i nr- i -ifJi il m i . . iruirtl .i X i i ., IjM In ., Oil i,ircrif .if I* UilW Lllllallit it'll tlnl n-J.T,-.- .I.ir Mill liiiravuu itf (In e*iTT> TiP icni-I I _ - 11 i ir J I Ml M -ill -- - I Iilii Ii , nln -- .r i i ir< - wh pnnfl+ jiic l ij I TIIi ll I lV1 T i .ii'.iij i. h i L i ' 11 - lad - -I. -. ji.l. wi-l. vanr ni -.r IJffl pl '...

Converter

This photograph shows the teedhorn before it was painted. Also shown are the supporting legs, straps, ties, and square washers used to mount the feedhom in front of the reflector. The plastic cover that comes with the coffee can is used as a radorne. overkill is for two reasons. First, there is generally no difference in the cost of the larger parts, so you may as well use them and have the added capacity, Second, the relatively stiff supply provides a very well-regulated voltage to...

Cljp Of I

Fig. 5. (a) Bottom-view layout of local-oscillator circuit board, The shaded area indicates the area etched away. Use single-sided G10 epoxy circuit board, (b) Schematic dtagram of oca osctf ator. Ql is Motorola MRF901. RFC1, 2 is 13.5-cm (5 -inch) 26 AWC close-wound using a piece of 74 AWG as a mandrel. CI is a 1-7-pF fohnson-type U (see text). R1 and R2 are V4-W metal film-type resistors. C2 is a modified 270-pF feedthrough tsee fextjor other small low-inductance capacttor. This capacitor is...

Usa Foreign Patents Pending

3455 CONNER ST., BRONX, NX 10475 U.S.A. I . TELEX 125091 MINIMUM ORDER (25.00. SHIPPING CHARGE 2.00. N.Y. CITY AND STATE RESIDENTS ADD TAX ihf folio in* 1COM. Midland. Am-ccht, Denl ron, KLM. Swan, Drake Ten TeL Wilton. ST, MFJ. H> -Cain. Lunar. Nye Viking BAW. Nedi-kilo ait, CttthCnft, Moile> . Signal* Pspo. tit. lull Servi Siore i itnuii Klf irflnk , A62Jt Sitrr f ifliim ( 13J5. 822-7710. B.i'n ' ncvkevi Amateur ftadtouorc Jl used Amateur Radio sales & service. We feature Kcnvtr-od,...

Frequency Counter

1979 Ham Radios

As much accuracy as you'll ever need Bill Pasternak WA6JTF Associate Editor easures frequencies to 600 MHz includes oven-compensated crystal timebase includes built-in 600 MHz prescater . . not an ad-on resolution to 1 Hz direct and 10 Hz prescaled sensitivity 10 mV rms 146 and 220 MHz to 50 mV rms 450 MHz accuracy .5 PPM over temperature, automatic decimal point placement 8 large bright .5-inch digits and more ' . Yes, these are nice claims for any piece of equipment, and, when you realize...

National Semiconductor

INCLUDES CRYSTAL TIMEBASE WORKS ON 12 VDC Originally used by HYGAIN to indicate time and channel on an expensive C.B. Mini size, self contained module. Not a Kit. Four digits plus flashing indicator for seconds. Includes MM5369 and 3.58 MHZ crystal for super accurate time base. With hookup data.

Put It Right Where You Want It

With one hand, raise the tower from 211 to as high as 55'. Find exactly he righl receiving level from CB, Ham or TV. When you want to adjust your antenna, install a new one, or pull maintenance, crank it down again. No more climbing up in ihe sky to repair or replace antennas. With the exception of our breakover models, this is the most convenient tower you can buy. BftEAKOVERS THE ULTIMATE IN CONVENIENCE Our breakovers not only telescope, they lie down for you. One man can crank it down, then...

Current Limit

Fig. 2. interna 723 functional block diagram few parts. Read on and I'll show you how easy it is to custom design your own regulator around the 723 to suit your particular application. Before we begin, let's look at a few characteristics of the device itself. The 723 operates with a, rectified and filtered input voltage in the range of 9,5 volts to 40 volts. The output voltage is adjustable from 2 volts to 37 volts with .01 line and load regulation. In case the terms line regulation and load...

Free Trial Copy

Mail the order form today and we'll send you your first copy at absolutely nn obiigation . , . that's right, if you're not completely satisfied after you've read your first issue, just write Cancel on your invoice and send it back to us * . . the first issue is yours to keep on us In addition, we'll guarantee every issue of your subscription . , . if you're not satisfied with your first- or your eleventh issue, we 11 refund your money on all remaining issues. Mail the order form today and get...

Mfj Kw Versa Tuner Iv

The MFJ-980 is MFJ's lowest priced 3 KW Versa Tuner IV but has the same matching capabilities as the other 3 KW Versa Tuner IV's, Features an efficient, encapsulated 4 1 femte balun for balanced lines. Accurate meter gives SWR, forward and reflected power in 2 ranges 2000 and 200 watts. 4 1 ferrite balun. The MFJ-981 3 KW Versa Tuner IV is one of MFJfs most popular Versa Tuners, An accurate meter gives you SWR, forward and reflected power in 2 ranges 2000 and 200 watts. Encapsulated 4 1 ferrite...

Code Forever

I have listened to your voice so much on the 73 Novice code study tape that i feel like know you. I hope to finish up the Novice test next week and take the General in the next 30 days or so. Please let me thank you for the outstanding study material. The letter from Jack McCord KA4EXD published in the May, 1979. issue of 73 was most interesting made me stop and think a little. Here I am at age 42 working on a Novice ham license, looking forward to all of the possible new contacts and friends...

Lunafts New Model M Linearized

We held off on announcing it until it was right Ready now Order today from your Lunar dealer. These unique antenna towers can be installed on the ground or roof. Since they're easily transported and site erected, they're a natural for field and portable operations. Constructed of sturdy aluminum alloy, they're sturdy enough to handle large size HF beams and are available for up and down converter systems Can be connected in any combination your system dictates....

Tempo Introduces New Kfz Miniature Tribander Antenna

Henry Radio has announced the full availability of a new miniature K6F2 20 15 10 meter tnbander antenna under ms Tempo brand name, Measuring only 8 feet square, the new antenna is based upon a fulf half wave-long constant-current loop design using capacitive phase shifters in the outer arms to achieve front-to-back ratios on the order of 15 dB. Gain over a full-size dtpoJe is 1 dB, The new Tempo tribander is constructed mainly of exceptionally strong and lightweight fiberglass antenna rods made...

Hdt Tripods

UPS Shippable. HDT-10KD 10 tripod, hvy duty 49.95 g HOT5 5 tripod, galvanized 24.95 f HDT-3 31 tripod, galvanized 15.95c 17.50 c . 8.95 c . 1.54 a . 3.46 b .4.35 b ST-SN Stainless chimney mt (pair) . PFM71 Hvy duty self sup roof mt 2791 Guy wire wood screw hooks (3) 2751 'thread x 7V turnbuckle (3) 2876 100r 8 alum ground wire 8.19c GND*4CP4 copper plated grnd rod. , . 3,39c S-1625P 2Vs ft. x 1 Vj mast 3.95 c A-125-5P 5 ft, x 1 i 4+t alum mast 11.50c WHEN...

Riters The Crowd

The new OMNI SERIES B makes today's bands seem less crowded. By offering a new i-f selection that provides up to 16 poles of filtering for superior selectivity. And a new Notch Filter to remove QRM. No other amateur transceiver we know of out-performs it. NEW 1-F RESPONSE SELECTION. OMNI comes equipped with an excellent 8-pole 2r4 kHz crystal ladder l-f filter which is highly satisfactory in normal conditions. But when the going gets rough, the new OMNI SERIES B. with optional filters...

Vhf Fm Receiver Kits From Hamtronics

1979 Ham Radios

Hamtronics, Inc., has just announced an exciting new series of VHF FM receiver kits. The model R75 is the fourth generation receiver by Hamtronics. and it incorporates all the design features of the previous designs plus some new ones. The chief feature of the R75 series is a wide range of selec iivity options. Four models, with different crystal filters, provide the optimum selectivity foreach type of service, ranging from 30 kHz at 60 dB for weather satellite reception to 15 kHz at -100 dB...

Prototype Boards

1979 Ham Radios

B-5 5V(Complete) B-12 12V (Complete) B-B Bare Board T-5 5V Trans or Powerbuses Accepts Up To 25. 14 Pinpaeks Provisions Made For Either 5V at 3 ma. or - T2 V at230 ma. By Simple TraosiarmerChange * Complete With All Parts Gnar e (0 VISA or MASTER CHARGE 01 mail us a chscfc q* tioisv oril r. include MS prli fl piua S3.00 snipping hafltfEkig Ohio FB& WiPllB add c.'t sales Ia . ts* Rest der Service see pa g e 1 9 109 Prices ifi (his catalog subjecl to change without notice. Prices good only...

Oklahoma City Ok

The Private Satellite Seminar,0 sponsored by Bob Cooper, Jr,, Editor-in-Chief of CATJ Magazine and host of the Satellite Magazine television program, will be held on August 14-16, 1979, at an educational institution in Oklahoma City, Oklahoma, Highlights will include a two-part seminar on the TO 2 conversion and a two-part seminar on the Howard Ter minal complete plans included in registration packet . Numerous manufacturers will be on hand to demonstrate their equipment and to investigate the...

Jacksonville Fl

The Jacksonville Hamfest Association is pleased to announce the 1979 Jacksonville Hamfest and ARRL North Florida Section Convention to be held on August 4-5, 1979, at the Jacksonville Beach Municipal Auditorium, Jacksonville, Flor ida. The location is just one block from the beach, where U.S. 90 meets the sea. Advanced registrations are available at 3.00 per person from R, J. Cutting W2KG1 4, 303 10th St., Atlantic Beach, Florida 32233. Price at the door will be 3.50, A large indoor swap area...

Decatur Al

The North Alabama Ham Association wilt hold its annual hamfest on August 18-19, 1979, at the Calhoun Community College gym in Decatur, Alabama. Examinations will be administered by the FCC, door prizes will be given, and tickets may be purchased for other equipment drawings. Camping is available at nearby Point Mallard. Talk-in on 146.40 147,00, 146.34 94, or .52 ,52. For more information, write to the North Alabama Ham Association, Box 9, Decatur AL 35602, The Straits Area Radio Club will hold...

Pittsburgh Pa

The South Hills Brass Pounders and Modulators wifl hold its 42nd annual Pittsburgh Hamfest on August 5, 1979, from noon until dusk at the Allegheny County Community College south campus on Rte. 885, 2 miles south of the Allegheny County Airport and approximately 15 miles southeast of Pittsburgh, Pennsylvania, Advance registration is 1.50 2.00 at the door. There wifl be a large indoor air-conditioned area for vendors and the flea market, and a large paved surface for the outdoor flea market....

T Subscribers

H From lime to time 72 Magazine makes its subscriber lists available rto carefully-screened companies and organizations whose products, r services or informal ion may be o interest toyou, innwerycase, we must approve all organiiations wishing to mail to our subscribers In every case Ihey receive a list of names and addresses onty no other information we may have is divulged. Each organization may use the list only once and agrees never to make any personal or telephone solicitations from it The...

Bolts Hoiking Ubracket

Buffing fort W4VGZ 2736 Woodbury Drive Burlingion NC 27215 Why doesn't someone tell parts distributors and transformer manufacturers that nobody designs tube circuits anymore, let alone builds them. Catalog pages are full of filament transformers and they are being bought because nothing else is available. Manufacturers seem to be rushing to resupply this so-called great demand. There are two dc voltages that I generally need supplies to provide +5 volts for TTL and +13.6 volts as a car...

Novat Ion Amateur Radio

For over 18 years, 73 Magazine has been the innovator in amateur radio. 73 led the way in developing the use of solid-state circuitry, and was the firs to pn mote such things as SSTV, radioteletype, computer applications for radii) communications, and single sideband. Radio electronics lias changed as 73 has changed. Ever notice how other magazines published in the field of radio electronics are just like the ones before them Same old subjects in every issue, same predictable views* same old...

Imyl Dlts Lzkrr Cob Guup

244,925 183,150 182,250 153.655 152,800 F. Rossi OKI 11857 B. Niendorf G8CDW K, Wustner 218,550 209,700 206,640 72,600 70,265 After my article appeared in the April, 1979, issue of 73 (The Heath Kenwood Connection), I found a small refinement which could be added to the project. Its total cost is small and it should take only a few minutes to install. 1 realized that one could use some method of instantly bypassing the remote vfo aside from using the function switch on the remote vfo. For...

Memory Chip

Now you can play with memory without playing havoc with uour budget try our 21LQ2 special, and get fen IK static RAMs for only 9,90 (that's less than 1C per byte ) These are low power units, suitable for use with an 2 MHz computer system, and are new. prime, high quality parts. TERMS Add t Handling to orders under 315 Allow up to shipping, more for power supplies (excess refunded), Give street address lor UPS delivery VISA< Mastercha - call our 24 hour order desk ai (415) 562-0636, CODs OK...

Complete Line Of Ode Antenna Rotor Systems

Comell-Dubilier Electric Corporation has released a new eight-page color brochure presenting their complete line of antenna rotor systems. Each of the six rotor systems is illustrated and described. They include the TaiJtwist-er , designed for king-sized antenna arrays of up to a 30 sg. ft. wind load area the new Ham IVTM. the latest version of the world-famous Ham series the new CD 45. incorporating professional features at a popular price the BIG TALKTM, with IC control that lets you...

Receiving Converters

Let you receive OSCAR and other exciting VHF and UHF signals on your present HF or 2M receiver Offers Unprecedented Range of Selectivity Options Linear Converter for SSB. CW, FM. etc A fraction of the price of iiher units Use 'ow potter tap on exciter or attenuator pad 1o align with buiilin esi points Link with VHF RX converter for transceive

Optional Accessories

Touch tone pad 55 * Tone burst generator- 29.95 CT'CSSsuh-audible tone control 329 95 * Rubber flex antenna SB Leather rtoistrtf 16 * Cigarette lighter plug mcbita charging unit 6 Matching 30 watt output 13.8 VDC power amplifier (S30i 89 Matching 80 watt outpuT powor ampNfier (S60* Si69 Belter than ( 5 watts Sensitivity Better than 5 microvolts Price , S349 DO With touch tone pad S339 00 The Tempo tine also features a fine iine of extremely compact UHF and VHF pocket receivers. They re low...

Pocket Cricket Transistor Tester

Sencore has recently introduced a new pocket-stzed transistor tester to meet the increasing need of solid-state field service. Battery-operated, and weighing only 14 oz-* the Pocket Cricket is totally prepared to check virtually all transistors and FETs on the market, in or out of circuit. No setup book or transistor data is needed at ali to check transistor gain and leakage between all transistor elements. This patented new device has the unique capability of automali-caily connecting the test...

Delaware History Gloryland Park Bear

The fourth annual New Delmarva Hamfest will be held on Sunday, August 19, 1979, at Gloryland Park, Bear, Delaware Donations will be S2.00 in advance. and 2.50 at the gate. Tables are available at 3.00 each. Tailgating will be 2.00 per space. There will be many prizes, and food and drinks will be available. Talk-in on .52Z.52 and ,13 73, For tickets or information, send an SASE to Stephen Momot K3HBP, 14 Balsam Rd., Wilmington DE 19804. Make checks payable to Delmarva Hamfest. Inc.

Famous Hamtroncs Preamps

Let you hOcir the w sk ones too Great lor OSCAR SSB. FM. ATV Over 14.000 in use throughout the world on atj types of receivers. Deluxe vhf model tor applications where space permits tV1*3 * Models available to cover any 4 MHz band in the 26 1c 530 MHz range 1 2 Ydc 2 stages Ideal for OSCAR 20 dB gain Miniature vhf model tor t hl s paces-size only & x 2 H I Models available to cover any 4 MHz bend in the range 20 O 230 MHz 20 db gain i2Vdc I Cowers any 6 MHz band in UHF range ol 380 to 520...

Code System Tapes

Code, sent at theottictai FCC atandard (no other ape we *ieard uses nese standards so rnany people flunk the code when they are suddenly under pressure faced with characters sent at t3 wptr and spaced for 5 wpmi This tape Es not memorable, unlike the zany 5 wpm tapeh since the code groups are enl irefy random characters sani in groups of five 20+ WPM CT7320 Code is what gets you wnen you go for ihe E*tra class license It Is so embarrassing to panic out just because you didn prepare yourself...

Rectified

FLA* PA Ctf DUAL - N L ME PA CKAGE Fig. 5. Low-voltage regulator (2 V to 7.1 V). To select com ponent values 2. Measure Vr (or assume Vr 7.1 V) 3. R1 Vr lb (lb is between 0.1 mA and 5 mA) 6. Rsc - 0.65 4 c (Isc max. output current limit) EtT IF S E -D AND FILTERED NPUT < 9.9 V TO 40V> EtT IF S E -D AND FILTERED NPUT < 9.9 V TO 40V> Fig, 6. Var ab e vo tage regulator (2 V to 27 VI To select component values 1. Choose Vo (here, Vo is the max, output voltage) 2. Measure Vr (or assume Vr...

The Tri Polarize

Mitchell K8UR 13356 Wabash Mian MI 48160 This article is about an easy way to achieve the various modes of polarization from a single antenna system, the VHC antenna. VHC-V for vertical, H for horizontal, and C for circular. The attempts of antennas in amateur use to . I--'- i -, ' Si*'1-' ' fl Jj * > achieve the different modes were either expensive (multiple arrays and multiple dollars) or exclusive to a particular mode. This ultimately re- suited in the purchase of many identical...

Check The Features And Yul Know

25 W& ttTransmitter (Iw low power) rf Provisions for non-standard offsets ri 800 Channel Scanner Option available if Oniy 295.00 ( 395.00 with scanner option) complete with microphone, mobile mount, etc. Order yours today and Go with the leader. modify earlier nnjtiei FM-Z 1*. Can or wnte ror to a red ochtjie 1911 Olde Homestead Lane Greenfield Industrial Park East Lancaster, PA 17601 (717) 299-7221 Qp e- Servie*1 sc*1 ninjf

Yaesu Ft Zd

Complete repair iab on premises Tubes and parts in stock Export inquiries expedited Spanish spoken Fig, 3L Hanging method B sloper. This method requires about 60' of yard space, but can be used if a tree or mast near the house cannot be utilized. satisfactory, if you continue to trim the 14 wire to a point where there is no more wire to trim and the swr is still too high, you must start cutting off 6-inch pieces of the antenna itself. Be sure that the braid and center conductor of the antenna...

Quasar Video Tape Recorder Salei

* Records to two hours, color or btock 6 white * Record* off the air record one pogrom while watching another *CamefO input to make your own tape* * Con be used with optional timer while yoo ore out * Limited supply-these St.000 VTRs were demonstrators Cj come with new warrantee , . . d99 100 worth of new blank tape wili be included at no extra chorge Bill MC Visa _ Arnex I Credit card ____I EHRHORN TECHNOLOGICAL OPERATIONS INC PO. BOX 70S, CA ON CITY, CO BW2 1303) 275 1613

The Woodpecker

I wanted to write you about the tetter in May's 73 Magazine concerning the Russian woodpecker. I tried the recommend ed procedure from the shack at the store, and it worked. It may have been coincidence, but soon after I began to send dits in time with the clicks, the in terference stopped. Even if it was coincidence (both times), it made me feel better I hope it ts really working, tor that damn noise has helped me lose more DX than just about anything. The gentlemen from the West Coast DX...

No More

The Novice 15m WAS Net has been discontinued and a 40m version started. Check-in on 7,135 at 0800 UTC on Saturdays, KA8AKL is net control. The April issue of 73 contains comments by Wayne regarding the 100,000 fiasco by the ARRL last year. This is old, old news, The fiasco was disclosed at the Pacific Division Convention at Reno last August as explanation for the large number of Handbooks donated for use as door prizes, f was the recipient of one. I know Wayne laughs all the way to the bank...

Us Sstv Contest Results

Once again, the annua) SSTV Contest was a joyous success and all contestants reported having the times of their Uves during this informal event. As you will recall, this US-sponsored SSTV contest is held during the second full weekend of each March. The overall 1979 SSTV Contest winner was Roland Soucie N6WQ of Costa Mesa, California. As you can see in the contest tally, Roland's victory was practically a landslide and he followed the correct (shorter contest times) rules which were published...

New From Flesher

*RTTY REGENERATIVE BAUD RATE CONVERTER TTL compatible connections (or direct hook-up to the TU-170, also adaptable to other units. ** Five standard baud rates ** Stable crystal-controlled oscillator m 128 Character storage capacity with storage status meter to show buffer fill * Continuously variable character rate

All You Need In One

Show ihe shack, home rnovi , computer ftim *, etc. Connect to th ant terminals or any TV sel, add a Rood 430 antenna, a camera, and you are there Show ihe shack, home rnovi , computer ftim *, etc. Connect to th ant terminals or any TV sel, add a Rood 430 antenna, a camera, and you are there * TO Watts peak RF output Specify 434,0 or 439,25 MHz Subcarrier sound with plenty of mic gniiri ior distance pick-Up. * 8 MHz bandwidth, high resolution necessary ior computer alphanumeric* and cotor. *...

Crystals In Stock

Standard * Icom * Heathkit Ken Clegg Regency Wilson VHF And Qlhers Lifetime Guaranteed Now owl Ices FOB Medford, MA, Check Enclosed MA residents ado sales tax. ping and handling on ALL c ORDERS. Signature D Master Charge Q Send for Free Catalog PRICES SUBJECT TO CHANGE WITHOUT NOTICE _ Card axp, date_

Order Now Tollfree

Credit card holders may use our toll free ordering number Ask for operator 701 (800) 824-7868 In California (800) 852 7777 Alaska and Hawaii (800) 824-7919 8817 S.W, 129 Terr Miami, Fla. 33176 Tel (305) 233-3631 M M the S2 olim coti* to the lower Impedance of A mobile whip, TajMi between S unci BO ohms. - > 0 Mt . t-LTKA rsFM nELXH G JlaichtfHU& unteiimi-Ciiun fed iir random *rlre oh ufl buridw MftfMO iuctcFs). Tmififc mit (1K SWR tin vqur anf uilu for more efficient npfrratt n ofunV rig....

Temperature Controlled Heating Plate

5 x 10 In. 120 VAC, 120 WATTS Made of 1 4 In. tempered plate glass with Nt-Chrome heating element laminated to back. Element size is4 x9'j Inches Double protected by Tl KLIXON Thermostat and two thermal fuses. Each also has neon ready light. Besides the obvious use as a bun warmer, food warmer, coffee warmer, glue warmer, etc.r our tests show this plate to be an excellent warmer for ferric chloride solution used in etching PC Boards by hobbyists. Typically increases etching efficiency by 300...

Toshiba Power Audio

5.8 WATTS RMS Typical Output, 50 to 30,000 HZ 3 DB For CB's, tape decks, PA's etc Works off of a single supply voltage from 10 5 to 18 VDC 10 Pin plastic DIP with special built in heat sink tab Perfect for use on 12VDC. sqqq With Data, 3 each P.O. BOX 401247 GARLAND, TEXAS 75041 (214) 271-2461 terms Add 5 C postage. pay balance Orders under S50 adci 75c handling No C.OD We accept V-sa MasterCharge and- American Express cards. Tex Res add 5 Tan Foreign orders (except Canada) add 20 P H 90 Day...

Low Power Ram Kits Buss

Thousands of personal and business systems around the worid use this board with complete satisfaction. Puts 16K of software on line at ALL TIMES Kit features a top quality soldermasked and silk-screened PC board and first run parts and sockets. All parts (except 2708's) are included. Any number of EPROM locations may be disabled to avoid any memory conflicts. Fully buffered and has WAIT STATE capabilities, OUR 450NS 2708'S ARE 8.95 EA. WITH PURCHASE OF KIT

Static Ram Kits Buss

'*Ve fefll the 31will bo thone Kt industry s'andafO RAM chip the 2102 was This means price, ivai I ability aod quality uyJI all be gooiJ Ne*t rhr 2114 is FULLY STATIC1 We feel this is (heONLY A ay to go on the S-10G Bu& s We've all heard the HORROR stories abou< some Dynamic Ram Boards having trouble wilh DMA anrl FLOPPY DISC DRIVES Who needs these kinds of problems And Imally, evsn among other 4K Static HAM stheSil 14 stands ouv Not ail 4K static Rams art created equal' Some of the otfi r...

Static Ram Ss Buss

Addressable on 16K Boundaries 4. Double sided PC Board, Solder mask and silk screened layout. Gold fingers. 5. Afl Parts and Sockets included 6. Low Power Under 2 Amps Typical BLANK PC BOARD 33 COMPLETE SOCKET SET 12 TM990 BUSS PROTOTYPE & WIREWRAP BOARD For use with the Texas Instrument Series of 16 Bit Microcomputer Modules. Fully buss compatibie. An inexpensive and quick way to expand the capacity of your Tl computer, Made of G-10 Epoxy PC material. Gold plated contact...

Dynamic Ram Chip

16K X 1 Bits. 16 Piri Package Same as Mostek 4116-4, 250 NS access. 410 NS cycle time Our best price yet for this state of the art RAM 32K and 64K RAM boards using this chip are readily available. These are newr fully guaranteed devices by a major mfg. very limited stock P.O. Box 401565 * GARLAND, TEXAS 75040 (214) 271-2461 TERMS Add 50 postage, we pay balance. Orders under J15 add 75c handling No C O D We accept Visa. MasterCharge. and American Express cards Te* Res. add 5 Ta*. Foreign orders...

Led Watch Guts

II'M M li t I.LH jffAnl r nQund Duly juallty- ' nrijm , jlmh *tt Die J(W fimiildifcciion 2 rwinw. iO- .Ono Ht. i MK lie 50 FM II O Jupoi clip uhm Imp duncL 1.5 VUC Cat. HO-JTlJq G m Pr in l Flat Magnifying Lsn * It'e different L'.'u uituauai Hnjtnini lik n lam, y ut it+i flat1 A Tin if fliill ttiiuwnirii ifi vtj H wihd frorn. rb(i m thi die wf the lens, ectiiifi li gL& ut priant Each proo-v tH-nd* tb 1 If ht whviH tHm hit it. acting I Liu* cuit vn in tD p I E i M ft a lit, iiuipeneiv*, nnd...

Gold Plated Card Edge Connectors

25 pins 3.49 ea 10 30.00 30 pins 3.96 ea 10 32.00 50 pins 5.43 ea 10 S45.00 43 pins 3.66 ea 1 30.00 TCDfcflC. All material guaranteed tt for any reason you are not satisfied, our products maybe returned wit tun today s for a full refund ftess shipping . Please add S3 ERMS for shipping and handling on aif orders. Additional 5 charge for shipping any item over 5 tbs. COO s accepted tor orders totaling SSOOOor more Atl orders shipped UPS unless otherwise specified Florida residents please add 4...

St Louis Mo

18 Is* Reader Service see page 179 Detachable control head of the IC-tiO, remotely mountable 2 meter mobile transceiver The totally detachable small front section of the IC-280 houses the microprocessor for frequency control and memory The IC-280's control head can store three frequencies of your choice which are selected by a four position front panel switch and these frequencies are retained for as long as power is applied to the radio's memory pin,,, even when the front pane switch is turned...

Mfj Versa Tuner

New efficient wound cm I Tar mart witti ovt. Only Mf j u e& an etrtcienf m wound irmuci (13 popthWKi ii. ihis class of tuners to girt ywip more watts > Ltr ana less losses rhj'i ,i tapped tofcid Matches iwyMimhi trom ieo rhfu 10 M& iflrs dipoles. inverted vees. rjiniir> m *ires verti cai& . mobile whips teams balance line * Jines Up to 200 watts RF output 1 4 bHun lor balance laics Tim out it* S pP if our matte Irtsfn nudt yw tar Wn i fr r yt- compact ,f i6 rctei comei 5 *i) btndmg...

Mfj S Ec Ono Keyer

Fand C nrreti Speed 9 to SO WPM . puit to tun , volume, on on. 3 CQodutiof V* men phone jack lo* kjytog cuiput nd itfly paddlo input Inter ml wthght control lets you adjust dot-flash space ratio tor a disincline tfgnal lo p& nelrats tJHM lor solid OX corriacis Skieiorit and ywaker Imtroai tone cwiirti Lunhc afttitiH witFi kty Dtf tfl& morv Instant stai St complete Jam rot spacing n+ixfit sart state ttyng gna taue* ca'hooe y*d ssitt WOT ncrs (- 300V, na ma and + 300V 100 ma ) For technical...