Linear Amplifier Project

Follow-up to January's 220 MHz transverterproject For those dedicated home brewers who have just gotten warmed up on the transvener project (Ian. '89 73)+ here is another item to apply the iron to the DMOS linear powcr amplifier. This amp is constructed on a 10 x 3 k V radiating fin heat sink. The linear output of this amplifier exceeds 60 Watts RMS on CW power. The heat sink is somewhat larger than required, and runs quite cool, The amplifier is contained in an attached box made from...

Apf

No discounts or commissions are available. Copy must be received in Peterborough by the first of the second month preceding the cover date. Make checks payable to 73 Magazine and send to Rebecca Niemela, Barter N1 Buy, Box 278, Forest Road, Hancock, NH 03449. 100 QSL CARDS 8i Shipped postpaid. Free samples. Shell Printing, KD9KW, PO Box 50A, Rocktor IL 61072, 3IMB059 HOSSTRAOERS flea market returns to Deerfield NH June 3. SASE for info. WA1IVB, RFD Box 57, West Baldwin ME 04091. BN8864

Antenna

NV 89015 At my place of employment, where an FCC commercial license (2nd Class General) Is required, less than 10 in a department of more than 200 employees are licensed amateur radio operators, though many expressed an interest in the hobby. At my former place of employment in the Telecommunications Dept., there were only two licensed people, though again, many were interested in ham radio. Why, in a nation with millions of electronic technicians, engineers, and...

Circle On Reader Service Card

Editor 7s Preface As digital technology finds a larger place in amateur radio, the same complex legal and ethical problems in the computer industry are hound to crop up. This article focusses on one such issue alleged software piracy that has hit the amateur packet radio community. The conflict started between two groups Software 2000f a software development company in the US and NordLink, an amateur packet radio club in Germany, Software 2000 developed a program, called Net ROMj to enhance...

Catalog

Work quite well in diffused light, such as hazy humid weather or cloudy skies. The crystalline cells will fall flat on theif faces under those conditions. Antennas West makes use of the Sovonics P-201 panel, It is rated at 23 War's under peak sum conditions. This boils down to about 1.6 Amps for battery charging. The P-201 measures one foot wide by four feet long, and weighs under five pounds. Antennas West supplies a 30-foot cable that is attached at one end to the P-201 panel. This is a four...

L

T-50-6 45 turns *2B Or 30. T-50-2 These pars must be obtained from eilher Hadiokit, Circuit Specialists, KF Amp ' his device amplifies itic ineom-ing received signals to give the receiver a little more punch and better signal-to-noise ratio. Mixer The mixer is a doubly-balanced mixer using the common IN4148 or 1N9I4 diode, 1'he difference between the antenna's signals and the VFO's frequency yields the audio frequency appearing at the speaker. This is the most fearsome looking...

International Hambassadors

Australia Ken Gott VK3AJU, 3BALansdowne Rci , St. Kitda. Victoria 3193 Austria Bahrain I an Cable A92BW. POS 223 1, Muharraq Bangladesh Belgium Brazil Gerson Rissm PY1APS, POB T217B. Copacabana, 20000 Rtode Janeiro, RJ Carlos Vienna CamdMo PYiCC. Afonso Pen5, 49 701. 20270 Rio de Janeiro British West Indies (See Urlted Kingdom) Canada Cftite Canary Islands (See Spurn Chma (People's Republic ofj Chang Han Dong (6Y4A0M) Inst of Esluahne Coasta Research. East China Normal Univ. h Shanghai 200062...

Helical Resonator Preamps

Features adjustable tail amp time-out timers, sol Ed-state relay, courtesy beep, and local speaker am plifi er 49 CWID kit. Diode programmed, adjustable tone, speed, and timer, to go with COR 3 59 NEW CQR-4 kit. Complete COR and CWID all on one board for easy construction, CMOS logic for low power consumption. Many new features. EPROM programmed specify call letters,. 99 NEW TD-3 5UBAUDIBLE TONE DECODER ENCODER kit. 24 TD-2 DTMF DECODER CONTROLLER kit. Full 16...

Ft Fm Ht

Cerritos, OA 90701 213 404-2700 Price Class 350 Yaesu has a long tradition of innovation in HTs. From the first digital-dispiayt microprocessor-controlled walkie the FT-207R to the first dualbantfer the FT-727R t they've led the way, defining the new frontier. This tradition continues with the introduction of the FT-411. The 411 is part evolution, part revolution. It packs into a shirt-pocket-sized radio all the features of the larger rigs and adds some terrific...

Info

MFJ, Bencher and Curtis team up to bring you America's most popular keyer in ajcompact package for smooth easy CW The best of all CW worlds a deluxe MFJ Keyer using a Curtis BQ44ABM chip in a compact package that fits right on the Bencher iambic paddle This MFJ Keyer Is small in size but big in features. You get iambic keying, adjustable weight and tone and front panel volume and speed controls 8-5G WPM , dot-dash memories, speaker, sidetone and push button selection of automatic or semi...

Six Meter QRP Stat on

Who says we don t use tubes anymore The unit described in this article proved the theory that It is possible to establish contacts at quite respectable distances with very low power. Designed primarih for mobile use. he station nms from a 6 volt batten. For 12 volt operation, the heaters will have to be rewired and changes made in the power supply. An AC supply is included, making it a station lor all-around use. Before going into the details of construction, here is a brief description of'the...

Qrp Swr Bridge

This simple project lets you monitor your antenna system's SWR. Low power QRP operating enjoys an enduring popularity in amateur radio. Much of the equipment is relatively simple to home-brew, and there isn't the need for many of the precautions required when operating at higher power levels. Opinion on what constitutes low power varies between different countries, and between different operators in those countries. The G-QRP Club's definition of less han 5 Watts input, and the American QRP...

Phones

F giire flecevVer schematic, pF capac tor from p Yj 1 to pin B of the 12AT7. precaution being that you keep the plate lends away from the grid leads. A 0.005 condenser is placed across the primary oi the modulation transformer to prevent any undesirable feedback. I wound the modulation transformer myself because there weren't any around at the lime. A Triad M4Z or similar transformer is best, Pa alteration to the receiver layout. The RF amplifier is u cascode using a 12AT7 or 6BQ7. Although the...

Mfj-1286 Gray Line

Select any of several antennas from your operating desk with these MFJ Coax Switches. They feature mounting holes and automatic grounding of unused terminals. They come with MFJ's one year unconditional guarantee. MFJ-1701, 34.95, Six position antenna switch SO 239 connectors. 50-75 ohm loads. 2 KW PEPr 1 KW CW. Black aluminum 10x3x1 V inch cabinet. MFJ-1702, 21.95. 2 positions. Cavity construction 2.5 KW PtP, 1 KW CW. Insertion loss below .2 dB. 50 dB isolation at 450 MHz. 50 ohm, 3x2x2 in....

E Ranger AR

Ranger Radios

Box 445 Issaquah WA 98027 Phone 206 392-0419 Price Class 350 When I last reviewed a Clear Channel Ranger 10 meter rigr I came to a couple of conclusions The first was that the rig was a reasonable,. alJ-mode 10 meter transceiver. The second was that it wasn't the most operator-friendly in the world. After evaluating the AR-3500, a higher-power, upoated version of the origmaf I have found some improvements, and some areas where things are pretty much the same. The Ranger AR-3500 is a...

Antennas West Solar Power Supply

Sovonics Solar Charger

Antennas West Box 50062 Provo, UT 84604 801-373-8425 Price Class 290 plus 10 shipping In the past, generating power from ihe sun was a hit or miss proposition. Most of the ear y solar electric pioneers used surplus panels, with sornewhai Jess than outstanding resufts. The technology and economics of converting energy from the sun directly into electricity have improved rapidly Antenmis West s solar power supply is an excellent first step in converting to solar power The heart of the Antennas...

R Extra

Call 913 381-5900 FAX 913 648 3020 continued from p 76 AH of us have ai least slightly different perspectives on these things. If you're working on a homebrew project and can't seem to get it to operate quite right, drop a line to the author There may be a spider or two that got into the article, if you do write, please, by ail means, send an SASE for your reply. I know from firsthand experience that those who send an SASE will get a reply quicker than those who don'L Jn...

Model Ccb Rf Detector

The hand-held Model CCB RF Detector from Optoelectronics will indicate the presence of a 1 mW transmitter within a twenty-foot distance. The bargraph display successively illuminates up to 10 segments as the distance to the transmitter decreases. This simplifies locating and deactivating the unauthorized transmitters, or bugs, placed in rooms for listening to private conversations. Other applications include checking the output from small or large transmitters used in radio telemetry, two-way...

Qrp Cw Transceiver

Tube Qrp Transceiver

A great little do-it-yourself DC rig for the 30 or 40 meter band. by Bruce Auld NZ5G and Bill Heishman N5HNN Much of the fun in amateur radio comes from having done it yourself. In my search for a project that would yield a unit with satisfying performance. I found two common problems The writer assumed loo much knowledge on the pan of the builder and the pans were not widely available. This project is different. The builder gets a running start in home-brew with something that will deliver...

1

We are nappy to provide Ham Hefp listings free on a space available basts. To make our job easter, and to ensure that your listing is correct, please type or print your request dearly, double-spaced, on a futl 6 V x 11 sheet of paper. Use upper- and toiver-case lei tersf and print numbers carefully a 1, for example car be misread as the tetters t or i. or even the number 7 Thank you for your cooperation I am looking for sources of harm-related and IBM emulaiion software tor the Hewlett Packard...

Elktronics

Board VDG-1 provides a quick source of instant video especially useful for those active in ATV or SSTV. Four computer graphics screens 2 Hi-res 2 color bar come on a custom-programmed EPROM with your callsign. Since the VDG-1 operates from 12 volts DC, and measures just 3.75 x 5 it's ideal for ATV repeater identification or portable and mobile operation, You can switch from the l,D, to live camera. An automatic timer sequencer allows you to display all four graphics...

Circle On Reader Service Caro

Wilson Antenna 2 Commerce Center Henderson NV 89014 800 541-6116 Price Class 90 Get into some 10m mobile QRO with this whip. Now that we are neanng the peak of what promises to be the best solar aciivity in history, many operators are discovering the fun of the 10 meter band. It's a band which combines the attributes of HF and VHF. and offers lots of prime DX, With such recommendations, is il any wonder thai 10 meter rigs are selling like hot cakes, and that Novices are on the air using their...

N

Ow receive or leave messages with other local hams using the K gt K Bulletin Board featured on the smallest TNC available -the Heath HK-21 Pocket Packet. The BBS operates under your call with simple commands like St nd or Write a message, Kill j message and read he File messages currently on tht system And the HK-21 Pockct Packet is fully TNC-2 compatible. Hookup is easy. Plug In supplied cables instantly to most 1 IT v or wire a separate cable into your mobile nr base VHF or HF rij-i. Connect...

Ukh

220 to 225 MHz D-MOSFET Linear Amplifier F 1202 20 Watt gold metairzed power FET transistor, smgle-ended from Polycore RF Devices. 1107 Tourmaline Drive. Newbury Park CA 91320 DLM26GT N-Channei MOSpower FET from M A COM PHI. lnc.T 1742 Crenshaw Blvd.t Torrance CA 90501, Jones 2 prong male and femare bulkhead for source voltage input. 0 pin mike ype male bulkhead jack from Philmore Mfg. Co., Inc., Inwood NY 11696. 8 pin mike type female plug Philmore No. 1700, 2 95 list. 80th plug and jack also...

Hamlog Computer Program

Auto-logs, 7-band WAS DXCC. Apple 19.95. IBM, CP M, KAYPRO, TANDY, CR8 24.95. 73-KA1AWH, PB 2015, Pea-body MA 01960. BNB775 WANTED Sunair GCU-910A or GCU-935 Antenna Coupler. Ray Dunham, 1030 Hillside Ave Pacific Grove CA 93950, BNB790 ELECTRON TUBES AH types amp sizes. Transmitting Receiving, Microwave,,. Large inventory same day shipping. Ask about our 3-5002 special. Daily Electronics. PO Box 5029 Compton, CA 90224. 800-3466667. BNB792 R-390A RECEIVER PARTS Info...

Amateur Radio

Are you lif J 5- your Uine and Dioitry ub par k gt ggmg program 7 Bring your station into ibe computer age wfih LOG WRITE h uji it n-. -nu lt . li . r fra-rtdfy logging program written by Ed Troy jNG A'- I tXiW RJ t ,5 the fn ifci t occeuory i lt ir the compliii ham nation It umpli fica your Operdltoh acid gives you ihr ompctltivf d 1 in contesilh tf d l Xu LOGWKiTE work . wnl .11 I MM PCs and cosmpocthLi'M tOGWRlTE'i unique split screen feature illow tor jumulta-neous lag ini nui M prtigc amp...

Circle On Header

0aMfMV P C Jf C Uw5t 0-W5-OUt VT AfijUSt 0aMfMV P C Jf C Uw5t 0-W5-OUt VT AfijUSt 0 Jiuu. f'ToW I MCn itL V CflHTtT Marc I Leavey, M,D, WA3AJR 6 Jenny Lane Baltimore MD 21208 Well, I heard you. With the responses to the March 1989 RTTY Loop Reader Survey pouring in I mean it you really did respond to this one , many of you made one thing quite clear. You are anxious to anger your spouse, parent, or significant other and burn iittEe holes in the kitchen table with a construction project or two....