Rnal of the Radio Society of Great Britain 110111000

• II II I • • I IM! rnal of the Radio Society of Great Britain

A SELECTION OF RSGB PUBLICATIONS

See inside back cover for full list

teleprinter

r a di o dat a r e f r r c d e r b o o k V I-1F-11-11-4 F

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test equip ment for the radio amateur

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RADIO 301:111, 01 e-.14111113,1dAIN e e e e e et O S C AR 0 .111 1110111000 NE W FRO M 4átronics

NO W THE BEST IS EVEN BETTER Introducing the most comprehensive R.T.T.Y. TER MINAL UNIT you can, or indeed need, ever buy—the Catronics CT100 Mk2 Now incorporating a number of modifications, YOU have asked fo,: including Completely automatic receive/transmit modes. Protected and buffered input provided for TTY keyboard. Automatic re-generation of incoming tones. 11111111111•11K Special ft. interference suppression circuit, etc, etc. e 1. •

C•11.101.141 Inputs for: Outputs for: •••• - , MA. Audio FSK signal in V.D.U. or other TTL compatible equip ment 1111_11, Data in from V.D.U. (e.g. G3PLX) TTY Magnet - single or double current TTY Keyboard or Tape Reader AFSK to drive Transmitter Featuring a unique digitally controlled 'Autoprint' circuit which is a superior replacement for the 'Antispace and 'Autostart' facilities found on some other terminal units. The terminal will ignore most CW and phone signals but will respond to a correct RTTY signal Tuning correctly into an RTTY signal is made simple with a single 'correctly tuned' LED plus an additional 'Mark frequency' indicator. The FSK demodulator circuit utilises a special 'state-of-the-art' system to give excellent performance and stability at low cost. The demodulator is set to decode signals within 75Hz of nominal frequency i.e. 120P-1350Hz for space and 1370-15201-1z for mark, when in narrow shift position. The teleprinter interface unit incorporates electronic 'de-bounce circuitry to eliminate spurious switching from the Keyboard. The loop supply is protected by a separate fuse and is suitable for driving all single current and double current magnets known to be available.

VAT inclusive prices are as follows: CT100 Receive only £0.00, CT101 Receive/Transmit £93.50. CT102 with Teleprinter interface £.94.50, CT103 Complete Terminal Unit £98.50. All models plus £3.50 Securicor delivery G3PLX RTTY VIDEO DISPLAY NEW 10 WATT 2M PA KIT (April 1977 Rad Corn) Kit (excluding modulator, keyboard and P.S.U.), £83.55 Set of printed circuit boards £15.20. UHF Modulator kit £11.95. Flashing cursor kit £8.60. Diode Matrix kit £13.25. Suitable mains P.S.U. Transformer £2.75. Catronics UHF Modulator. £15.00. NOTE regarding PROM program: The PCBs and programmed PROMs supplied by us make use of a slightly different program sequence resulting n different pin connections to those published in the 'Rad Corn' article. Whilst constructors buying PRO Ms and PCBs from us will have no difficulty, those producing their own PCBs or having PROMs programmed elsewhere should note this important difference. A detailed modification sheet is available with the PCBs. KEYBOARD KIT The printed circuit Ooard is designed to taxe a maximum of 70 keys but may be assembled with a smaller number of keys for a simpler keyboard. A 10 WATT output version of our famous 40 WATT 2M P.A. kit is now available, for The board is not dedicated to any specific coding, allowing it to be us- boosting the OUIPUI of 1 2 watt 2M FM transmitters. ed for any project whether it requires ASCII, Baudot or any other code. 12 volt supply Auto T/R switching This makes it suitable for many projects including; Complete with cabinet and full instructions Kit price £18.00 inc VAT • 65p post G3PLX RTTY VDU Also available ready.bullt at E28.00 Auto morse sender. etc. The Keyswitches themselves are single pole push-to-make type and require no extra mechanical mounting arrangements. 40 WATT PA KIT A legend sheet is provided with each kit enabling the constructor to label the keys to suit individual requirements. still available at C19.50+ 65p post Requires 12 volt supply and ID watts drive. Price: only M AO. Please add 50p for postage. Also available ready-built at E29.50

SEE ALL OUR PRODUCTS AT ALEXANDRA PALACE EXHIBITION

All prices include VAT but please add minimu m of 30p for p&p. Data — Catalogue available at 45p + large (A4) 18;p SAE DEPT. 906 COM M U NIC ATIONS HOUSE, 20 WALLIN GTO N SQU ARE, W ALLIN GTO N, SURREY SM6 8RG Tel: 01-669 6700 Open 9am to 5.30p m Mon to Fri, 9am to 1pm Sat. Closed for lunch 12.45 to 1.45p m ISSNO033 780 EDITOR A. W. Hutchinson

Assistant editor radio Mrs M. J. Collins communication Draughtsman D. E. Cole

Editorial secretary May 1979 Volume 55 No5 Mrs J. D. Brown CONTENTS

Contributions (including Members' Ads) and all 408 Current comment. QTC correspondence concerning the content of Radio 410 A frequency counter for a 144MHz transmitter— Communication should be addressed to: N. B. Pritchard, G8AYM The Editor, RSGB, 416 An inexpensive high-Z accurate transistor voltmeter— 88 Broomfield Road, R. E. Barber, BSc, G3NEF/ZC4RE Chelmsford, Essex CM1 1SS 418 A modification to the G3ZSS digital morse code generator— K. J. Marley, G3EIO/HB9ALV Tel 0245 84938 420 The "miracle sky hook"—A. D. Taylor, G8PG Office hours: 0845-1645 422 Technical topics—Pat Hawker, G3VA 428 International Conference on Antennas and Propagation— Correspondence concerning the distribution of L. A. Moxon, G6XN the lournal and all other Society matters should be 429 New products—Frequency counters addressed to: 430 Now it can be told—the Fareham "saga"—J. W. Swinnerton, RSGB Headquarters, G2YS 35 Doughty St, London WC1 N 2AE 432 Reception and processing of TIROS-N weather satellite telemetry (Part 2)-1. Gilbert, G4CEB, and T. J. Terrell, Tel 01 -837 8688 DipEE, MSc, PhD, CEng, MIEE Office hours:091 5-1 71 5 435 Microwaves—Charles Suckling, G3WDG 436 4-2-70—Graham Knight, GM8FFX 441 VHF/UHF hand planning—Tom Douglas, G3BA, and Ian ADVERTISING White, G3SEK Advertising, other than Members' Ads, 442 The month on the air—John Allaway, G3FKM should be sent to: 445 Propagation predictions

Mr C. C. Lindsay, 446 IIF propagation study 2 Leyburn Gardens, 447 Solar and propagation information in GB2RS news Croydon, bulletins—C. E. Newton, G2FKZ Surrey CRO 5NL 448 Raynet—R. Bullard, G8NM W. RSGB committees, 1979 Tel 01 -686 5839 449 Your opinion Hours: 0915-1715 450 Contest news 451 Contests calendar

EDITORIAL PANEL 452 Obituaries 453 Mobile rallies calendar. Special event stations J. P. Hawker, G3VA R. F. Stevens. G2BVN 454 Club news 461 Members' ads 464 Looking ahead

Radio Communication is published by The Radio Society of Great Britain as its official journal on the first Thursday of each month and is sent free and post paid to all me mbers of the Society

ABC 21,498 copies per Closing date for contributions issue average unless otherwise notified: ,C RADIO SOCIETY OF . 116 . •nd C MC .11110.1 circulation in 1978 1st of month preceding month of publication GREAT BRITAIN 1979 Ci) ICO M lol

SOME ICO M PRICES ARE DOWN! (for the time being) SEE THE FULL RANGE AT ALLY-PALLY

THE LEADER BASE STATION IC-211E Fast becoming one of the most popular base station rigs because of its superb performance and advanced technology, the IC-211E leads the field in 2M base stations. With a full synthesizer which employs state of the art technology it provides all you want for full coverage on FM USB. LSB or CW on 2 metres with that extra bit of quality for which ICOM are so renowned, plus the chance to use the latest digital technology and even drive it from your home computer if you wish! Less VAT = £464 With VAT= £522

THE MOBILES The IC-245E is probably the only multi-mode mobile on the market. Of course, it can also be used as a base station, and many own one for just this purpose. It employs all the same technology as the IC-211E, and is in fact virtually the same electronically with the exceptions that it only operates on USB, FM and CW and does not have VOX and sidetone or full seven digit readout. As with the 211 you have access, IC-245E via a multi-way plug on the back, to the LSI synthesizer for connection of a keypad, computer or other bit of home-brewed logic. NO W £399 inc. Less VAT=E354.67 With VAT =1399

IC-240 NO W £189 inc.

The IC-240 is the ideal mobile rig for most people. Apart from the fact IC-280E that it is quite a lot cheaper than most, it is, in fact, more suitable than NO W £245 inc. many to use in the car while driving (and let's face it, it is under those conditions that most mobiles are used). It can be operated with ease without taking your eyes off the road and provides up to 22 channels lwhich is more than you are likely to need). Being synthesized, of course, there are no crystals to buy for extra channels. Full repeat, As usual, ICOM have kept ahead with technology and have produced reverse repeat and automatic tone burst plus a low power facility are their revolutionary new IC-280E which uses a microprocessor to selectable from the front panel. By adding a 'Superscan at a later date produce frequencies throughout the 2m band at the ideal 25kHz spacing required today The IC-280 has the ideal advantage of being you can obtain full scanning facilities over the whole hand at a VERY separable into two parts for easy mounting into today's cars which so competitive price. often forget to leave space for a rig. The removable front panel, with The IC-240 is a superbly built and very reliable piece of equipment as all controls, is only 3" deep and will fit in any convenient spot -in the witnessed by the many thousands in use. All loom equipment is built to a very high standard and the IC-240 is no exception. It has an ex- glove pocket, on the dash or even on the sun visor! The main part of cellently sensitive receiver and a very clean transmitter and will give the set can be mounted anywhere within 4 feet - or even further in you hours of headache-free pleasurable use-so why not get one now many cases - under the passenger's seat is quite handy! Display is of frequency on an LED readout and there are three memories for your before the price goes up again! favourite channels. These are not cleared when the set is switched off 240 Alone Less VAT= £168.00 With VAT-= £189.00 With Superscan Less VAT = E230.22 With VAT =L259.00 as long as it is left connected to the car battery. (while stocks last) Less VAT = £217.78 With VAT =f245

AGENTS (PHONE FIRST- All evenings and weekends only. except Norfolk and Burnley) Scotland-Jack GM8GEC 1031-665 2420) Norfolk -Ted G3FF W (05088 632) Wales-Tony GW3FKO 10222 7029821 Burnley - 38481) Midlands - Tony G8AVH (021-329 2305) North West-Gordon G3LEQ 1Knutsford (05651 4040) Yorkshire- Peter G3TPX 1022678 2517)

H.P. TER MS AVAILABLE FOR ALL MAIL ORDERS AND SALES DURING BUSINESS HOURS

YOUR SOLE AUTHORISED UK IMPORTER FOR ICO M BARCLAYCARD THANET ELECTRONICS 143 Reculver Road, Beltinge, heme Bay, Kent (02273 63859)

386 RA DIO CO M MU NICATION May 1979 ilicom LEADERS IN THEIR FIELD

The IC-215 is getting more and more popular also as it combines the advantages of a portable, which can be operated anywhere, with the ability to double as a low power base station by virtue of its 3 Watts of output and S0239 antenna connecter on the back. Of course there are facilities to operate it from an external power supply, and if it is fitted with Ni-Cads you can arrange to trickle charge these at the same time. IC-215 The batteries used are of a sensible size being C type I or UIII instead of £159 inc. the 'penlight' batteries used by most of its competitors. This gives at least three times the operating power when you are away from home which you will appreciate if ever you have run out of battery in the middle of a OSO! It comes already crystalled up for 12 channels, S20, S22 and all the repeater channels 0 to 9. We think the extra power and larger batteries far outweigh the advantages of having the extra channels produced from a synthesizer. Less VAT =f141.33 With VAT i--£159

ICOM's range of sideband portables has been recently expanded. The IC-202 well known and tested IC-202E has now been improved in the form of the IC-202S which has lower side band fitted also and provides £199 inc. sidetone on CW. The receiver has been hotted up making it even more suitable for use as a base station, either barefoot or as a prime mover. The new IC-402 is the 70cm version of the 202S giving the same facilities as its 2m cousin over the range 432-435.2 MHz. Both use a very stable VXO circuit, to give fully tuneable coverage of the band in 200kHz segments and both have extremely clean signals so that using them to drive a linear to the full legal limit presents no problems. We are very impressed with both the 202S and the 402. The IC-202E was good . . . these are even better! IC-202S Less VAT =E176.89 With VAT =f199 IC-402 Less VAT =E256 With VAT =288

OR IF YOU WANT A HAND-HELD—

HO W ABOUT THE AR-240?

Although not made by ICOM, we decided to take this exciting new little SOME PRICES ARE hand held into stock because it fills the need for a really good portable where size is of prime importance. It has an amazing performance with a DOWN! truly excellent receiver. A synthesizer is used, with decade switch read A few months ago we had out to cover the range 144 -148MHz in 5kHz steps and 600kHz repeater shifts and a tone burst are built in. It comes with NiCads, a charger and a to put up prices because of telescopic whip antenna—though if you want to make things even the poor state of the pound. neater then you can use the ICOM FA1 flexible helical in place of this. Now things are better we At E195 inc VAT we think this is really good value for money. are pleased to bring some AVAILABLE NOW DIRECT FRO M HERNE BAY of them down again. Let's Less VAT = £173.33 WITH VAT = £195 hope things stay this way!

AR-240

Phone—or put a message on the ansafone for further details

ALSO AVAILABLE FRO M OUR SHOP IN HERNE BAY

MICRO WAVE MODULES ANTENNA SPECIALISTS

J-BEA M YAESU MUSEN FDK

HP AND PART EXCH ANGE WELCO MED

RADIO CO M MUNICATION May 1979 387 SEE IT AT GID ICO M ALLY-PALLY THE 'REMOTABLE' 2m RIG

IC-280

25kHz SPACING OVER THE WHOLE BAND: 3 MEMORIES: LED READOUT: BUT MOST IMPORTANT-ICO M QUALITY

lcom's new 2 meter mobile has a detachable long as power is applied to the radio. Even when microprocessor controlled head, easy to read LED's power is turned off at the front panel switch the pro- and a new style meter set in a brushed aluminium grammed memories are maintained; and the 600kHz front panel. repeater shift is always retained.

The 280E comes as one radio which can be It goes without saying that the usual high quality mounted in the normal manner but as an option the engineering for which lcorn are renowned is found in entire front one third of the radio detaches and can the 280E. There are no nasty shortcuts to try to keep be mounted in that small location in the car (such as the price down to the detriment of performance. the glove pocket) where other sets are just too large to fit, while the main body tucks neatly out of sight It includes the latest innovations in large signal several feet away—such as under the passenger's handling FET front ends for excellent intermodula- seat. No longer do you have to mount a radio in a tion performance and good sensitivity at the same position where it is poised all ready to smash your time. The IF filters are crystal monolithics in the first right kneecap should you have an accident! IF and ceramic in the second, providing narrow band With the microprocessor head the IC-280E can capacity for today and tomorrow's crowded store three frequencies of your choice, which are operating conditions. Modular PA construction with selected by a four position front panel switch. These broad band tuning provides full rated power across frequencies are retained in the 280E's memory for as the full 2 meter band.

FROM THAN ET ELECTRONICS OF COURSE

388 RADIO COMMUNICATION May 1979 ICO M TWO GREAT STATE-OF-THE-ART RIGS

1 IC-211E 2m All-mode Covering the full 2 metre band with fully synthesised multi-mode operations. the IC211E is the most advanced, highest quality 2 metre transceiver available anywhere. The IC2115 comes complete with ICOM's single-knob frequency selection and two digital VFO functions, standard features at no extra cost. SMALL ENOUGH FOR MOBILE! The large weighted flywheel knob mounted with low friction ball bearings is used to drive an optical chopper to provide pulses to the synthesisers LSI, which shows The 1211 contains both 240vac and the 13.6vdc power supplies and has a built.in a full 7 digit readout. A breaking mechanism, which operates electrically, engages high SWR empower control. Variable output power contributes to the IC211's to provide a smooth feel at slow speeds; and a "'dial lock" button holds the versatility. Output between 500 milliwalts and 10 watts may be front panel con• reading at the time it is pushed, even though the knob continues to rotate. trolled on FM. The IC211 incorporates computer compatible interface via the 24 pin accessory More of the maximisers built-in standard features include: a Pulse type IF noise socket on the rest panel which enables PIA connection for the microprocessor blanker; front panel discriminator meter. SWR meter; VOX with adjustable VOX buff. gain delay and antivox; ON monitor volume level; and semibreak-in ON opera- The IC211's synthesiser steps are displayed, with positively no time lag. backlash tion. or uncertainty in display stability, in increments of 100Hz or 5kHz from And your new IC211 carries the THANET 1 year warranty backed by spare parts 144-146MHz. Any offset for repeater use can be program med. and technical expertise if bought directly from us.

COMPARE THE IC211 WITH THE OTHERS! £522 inc VAT 2. Computer compatible •

IC-701 HF £391

ICO M's superior LSI technology takes the lead in Amateur HF. The extremely microprocessor controlled accessory which will also provide remote band selec- compact IC-701 delivers 100 watts output from a completely solid state, no tune tion and other functions. (broad band design) final, on all modes and all bands. from 160. 10 M. With single knob frequency selection and built-in dual VFO's, the LSI controlled IC.701 is the Full band coverage of all six HF bands, and continuously variable bandwidth on choice in computer compatible, multi-mode Amateur HF transceivers. filter widths for SSB. RTTY, and even SSTV, help to make the IC-701 the very best HF transceiver ever made. IC-701 includes two CW widths, all of this The IC•701's single frequency control knob puts fully synthesised instant tuning standard at no extra cost. at a single finger tip. WIDE bandspread, with 100)1z per division and 5kHz per turn, is instantly co-ordinated between the smooth turning knob and the syn• Sold complete with the high quality electret condenser base mic (SM-2), the thesiser's digital read-out with positively no time lag or backlash (no waiting for IC-701 is loaded with many ICO M quality standard features. Standard in every counter to update: less operator fatigue). And at the push of the electronic high IC-701 are two independently selectable. digitally synthesised VFO's at no extra speed tuning button, the synthesiser flies through megacycles at 10kHz per step cost. Also standard are a double-balanced schottky diode tot mixer for excellent (500kHz per turn). receiver IMO, and RF speech processor, separate drop times for voice and CW VOX, optionally continuous RIT, fast/slaw AGC. efficient IF noise blanker, fast The computer compatible IC-701 LSI chip provides input of incremental step or breal,in CW. and full metering capability. digit-by-digit programming data from an external source, such as the from THAN ET of course.

RADIO COM MUNICATION May 1979 389 WATERS & LOOK! 1211(Hz or 25kHz + 25 watts STANTON ELECTRONICS

FDK MULTI-700E

F229 inc. VAT 8- delivery

What can one say about a transceiver that has proved to be so perfect in design. Truly a concept that looks to the future as well as the present. Its powerful 25 watts ensures better coverage than its competitors and its 25kHz stepped frequency synthesizer means no more xtals to buy. And to match its powerful output two receiver RF stages are provided that typically give about .3uv or better for 20db NO. Reliable repeater operation is ensured by a crystal controlled tone burst and a pre-wired « kHz shift. Listening on the input of the repeater or reverse repeater operation is obtainable at the flick of a single switch and the 25 watts output is continually variable down to 1 watt. A remarkable transceiver at a remarkable price- little wonder more and more people are saying. "I'm using a Multi-700E at this end, 0.M." And one final point, it also tunes ul 12;kHz steps and with the specially designed receiver filter 1231tHz operations is immediately possible. IN STOCK NO W- ORDER TODAY.

NEW MULTI-3000 2m ALL MODE TRANSCEIVER

The Multi-3000 is the new 2 metre all mode transceiver to leave the FDK factory. it memory button enables one to lock the last frequency even down to 100Hz on features 15 watts of FM/SSB/CM/ with a host of features that keeps it in the SSB) and then carry an tuning around the band. At any time the memory button forefront of value-for-money VHF transceivers. A demonstration model is available can be pressed to return to the original stored frequency and pressing it again at our premises in Hockley and deliveries are expected May/June. returns you to the frequency you had just OSY'd from. In all, 3 frequencies can be The design retains the switch selected synthesizer which can be used for FM to stored, one on the switched synthesizer and 200 the manual digital dial. Further. select any channel quickly and accurately. The synthesizer tunes in 10kHz steps more the memory is not lost when the equipment is disconnected from the supply and a separate control inserts the 5kHz digit as necessary. Complete coverage cord. from 144 to 148MHz is provided and the three separate knobs for 1MHz. 1COkHz and 10kHz digits make OSYing extremely rapid. Repeater operation is taken care of by a pre-wired 600kHz shift and this also operates an automatic crystal controlled tone burst. FDK's dual vio facility is retained employing a separate flywheel drive with direct digital readout. Thus the switched synthesizer may be left on ones favourite FM All the usual features you are likely to need are also included: tone-burst defeat. channel and the vio used to tune around the band. In the FM mode two tuning VOX, Mie gain, AF and RF gain, noise blanker, receiver incremental tuning, fast rates can be selected. The -rate of tuning" switch gives either 10kHz or IkHz and slow AGc. High/Lower power switch, squelch, also internal presets for VOX steps. The former for rapid OSTing and the latter for final tuning to the desired gain, delay and anti-vox. The power supply is designed for 240 volts AC or 12 frequency exactly on any I kHz multiple. On SSS and CW the same tuning control volts DC operation and projected price is £519 inclusive of VAT. Another superb gives steps of either lkHz or 100Hz. In this mode the digital display reads ac- piece of engineering at a very reasonable price - FDK of course. curately to the nearest 10011z. Tuning has never been easier, And that's not all. A £519 inc. VAT Er delivery -available June.

390 RADIO COMMUNICATION May 1979 THE MOST ADVANCED FM RIG! WATERS sgt FDK MULTI 800D-25 WATTS NOW INCLUDES:- * 144-148MHz coverage * Remote 'up/down' microphone IN STOCK NOW * 2N1Hz and 4MHz band scanning STANTON * Dual memory * Electronic tuning ELECTRONICS

IN STOCK NOW— ORDER TODAY

FDK PALM II

2M FM THE SIZE: 6" x 24." x 12-" WEIGHT: lib 3oz MIGHTY COMPARE ITS VALUE COMPARE ITS FEATURES * Cigar lighter plug * External DC cord MIDGET * Over one watt output * AC charger included * 6 channel capability * Simplex or c,600kHz switch * 8NC aerial socket £139.95 * Flexible whip supplied £.29 inc. VAT (Remote display £19.95) * S/20/22 supplied inc. VAT * Extra channels cost C2.90! Send SAE for brochure * Xtal controlled tone-burst iXtal toneburst * Ni -cad battery pack supplied module £.50 extra ) * High quality condenser microphone MIZUHO-2M SSBICW Hand-Held ADONIS MICROPHONES. . IN STOCK NOW KEEP PEOPLE TALKING!

• ‘ 4 4 0 >

M8026 ¡illustrated) is the top of Fitted 144.20-144•40MHz am err MI MI" the range. Beautiful solid con- £165 inc VAT Er delivery anywhere in UK. struction yet slim lines and the famous electronic -Touch to Talk THIS RIG GETS TO PLACES ore but a few of its features. In addition, a 3-way switch normal OTHER RIGS CAN'T REACH! operation, medium or high com- There is no denying that for local cross town chats and nets, FM has a lot of ad• pression. A meter built into the vantages. Maybe you've been licensed a few months and thinking of working a base monitors the compression. lot of DX - and yes, you've found that on FM it is lust a little difficult- well, The high quality condenser insert how about trying SSS. With a watt of SSS and a single yagi antenna you'll be is enclosed in a noise cancelling amazed how far you can reach. And when those "DX lifts" come along you'll housing and 3 switched outputs be in there with more than a chancel What better way to get in amongst the DX are provided so that the than purchase an S82M. At £165 you'll find it impossible to beat for value. This microphone can be fed to 3 dif- really does form the basis for both a fun packed portable station or a compact ferent transmitters. Each output base station- if you can't afford to trade-in your FM rig for an all-mode rig how has its own output level control. If about an SB2M - think about it- there's quite a big savingl And remember you want a microphone to match Spring is just around the corner. With a set of HP7 cells loaded in the rig, the 1 that new rig then we have the watt output is the economical way to sit on top of the local hills or climb up into answer. the mountains and create your own DX pile•upl C59 including VAT.

RADIO COMMUNICATION May 1979 391 WATERS & DenTron USA SUPERB HF EQUIP MENT STANTON AT VERY SENSIBLE ELECTRONICS PRICES! DenTron GLA-1000 DenTron MT-3000A IN STOCK NO W 10-80m 1200W LINEAR 3kW 1.8 30MHz ATU LOW COST, SMALL SIZE, BUT . . . BIG VOICE £289 inc VAT DELIVERY FREE IN UK

Ir ••,:çi • e 11ELECTOR

lhf WOO

IN STOCK NOW Yes. this is the ultimate m ATU's. It matches anything whether it be long wire, balanced or unbalanced feed or garden fence! We know of no other ATU that te-W it una S GLA-10oo will handle the full output of some of today's big 2kW amplifiers but even if you are running one of the popular 1200 watt jobs. there's a lot to be said for the This beautiful HF linear covers 193 to 10 metres and has its own built-in MT3000A. Its huge ceramic insulated capacitors ensure tow loss aerial coupling 117 ,234V power supply. Its diminutive size means less table space needed but and its wide-range bandswitch means it really does give continuous without sacrificing power capability. Weighing in at just 24 pounds it measures coverage- we've even supplied a number of these units for commercial ap- only H.5yli" u W. Il u D.11" with room to spare inside. An almost silent fan plications! ensures cool running whilst the little power house generates 1200 watts input The front panel size of 5r x 14- means it's still desk top size and its com- on SSB or IkW DC for CVV. RF drive required is approx. 80 watts and the prehensive front panel controls gives you complete armchair selection of your amplifier can be instantly switched in or out of circuit. Comprehensive metering aerial system-in fact up to five different systems. Forward and reflected true monitors HF volts, PA current and output RF voltage. Altogether a linear we RF power is monitored (either 0-200 watts or 0-2kW) and for initial tune up can thoroughly recommend at a price you can afford-just £289 delivered. there is a 250 watt dummy load. This, more than anything else, is the one piece of eouipment you will never get rid of once you've bought -a good investment indeedl £75 inc VAT. DenTron NEW HF-200A DELIVERY MAY TWO SPECIAL BARGAINS 80-10m 200W TRANSCEIVER SUPER TUNER PLUS AVAILABLE JUNE Prov, Price Designed to handle the popular 1200 £399 watts linear, this ATU has all the Inc. features of its big brother the VAT MT3000 with the exception of dum- Et del my load and RF power metres. The latter is replaced by an RF output voltage indicator but the continuous .coverage and five selectable antenna facilities are retained. A real bargain at £112 inc VAT,

SPECIAL OFFER

A natural development from DenTron had to be the birth of a transceiver. PEP/S WR/PO WER METER Small, compact and powerful- it's simply that! Measuring only 4" high x 10" * Remote sensing head wide it makes both ideal fixed or portable stations with its 200 watts input * No external power needed capability. Simplicity coupled with performance was the formula-that's why you won't find a single tuning control on the front panel, apan from the VFO. 0 200 watts Simply select the band and operate. Its nominal 13.6 V DC supply requirement draws 750 m'a on receive with full audio output and 20 amps on voice peaks or 0 2000 watts CW. A matching AC power supply is also available for both 234 volts and 117 1.8 30MHz volts and a remote VFO is also being produced. So if you're the kind of operator who wants less in the way of gadgetry and more in the way of performance per £a9 inc delivery C take a closer look at the HF200A - we have a feeling you'll like what you see!

392 RADIO COM MUNICATION May 1979 WATERS & SPRING NEWS Hi-pot Multiple Hat Loaded! STANTON ELECTRONICS _ model HQ-1 iniature NEW! zrae:nd HYBRID QUAD Antenna MOSLEY MINI-BEA M 10,-15-20M HQ-1 A further stock of the fast selling HQ-aerials from USA has arrived. This amazingly compact beam covers 10-15 20 EXCLUSIVELY FRO M US metres and has a turning radius of 6ft. 2in. It will take the full UK legal limit and is the ideal way of putting out a big signal from a 600 watt model 185 small garden, 2kW model 1120 7;i' • Price: E94.50 (E2.00) _Miniature ;v7 (Sand Coaxial Vertical FIELD TEST RESULTS MODEL C4 £41.50 W1.50) Forward Gain: Max. Element Length 21f1. 28MHz and 21MHz 5d8 Boom Length 6h. The MODEL C4 features the patented 14MHz 4d8 Turning Radius 11It, multiple hat' principle which allows Front to Back Ratio 15dB Wind load 60Ibs. operation on the 10-15-20 metre Weight 17Ibs. S.W.R. at Resonance 1.5:1 amateur frequencies with a single feedline. The C4 operates as a full elec- NOTE: The performance of this antenna is almost identical to a full size array by virtue trical half wave on all bands. This of its low-loss capacity loading. unique feature permits the elimination of cumbersome ground plane radials SAE FOR DETAILS normally used with vertical antennas. OTHER MOSLEY MODELS I EX STOCK) The C4 mounts in minutes with inex- MUSTANG 2kW 10.15-20M £119.25 pensive TV type hardware. TA33 600 WATTS 10-15-20M £106.85 TA32 600 WATTS 10-15-20M £72.00 TD3JR WIRE DIPOLE 10 15-20M £24.20 JAYBEA M R 05 SVVL ALL BAND DIPOLE £27.00 VHF/UHF ANTENN AS PMH2/4M 2 way harness E9-39 (10-75 C5/2M 5dB colinear E30-96 1E2-00 ROTATOR BARGAINS! 5.212M Set. yaw (7-70 ICI -03 BY/2M Set. yagi E10•00 (11-00 UK DISTRIBUTORS OF JAYBEA M ROTATORS 10Yi2M 10 el. yogi E21•32 50 P8M10/ 2M parabeam E25•37 111.50 PBM 1412M parabeam E31 • 16 (U. 00 5XY/2M 5 el. x'd yagi E15-97 (CI -50 8XY /2M Bel. k'd yagi E19•91 112.00 10XY2M Set. yagi £26 •33 1E2 • 00 PMH/2C circular harness E5•09 (10-50 0412M 4 el. quad E16-31 (11-50 06/2M 6 el. quad C21•71 (1.2 • 00 05/2M el. slot E13-61 (C1-50 06/2M el. slot E18•22 ICI - 50 ACCESSORIES: 5VMK/2N1 vertical slot kit C3•83 (11-00 UR43 Cable lep rn. UGP/2M ground plane C7•03 ICI-00 UR67 Cable 54p rn. H0/2M halo head C3•26 CEO- 75 75 ohm UHF 18p m. Hfv1i2M halo — mast £3•88 1E0-75 PMH2/ 2M 2-way harness C6-80 (10-75 P1.259 plugs 60p PMH4/2M 4-way harness (16.34 ICI 00 S0239 sockets, 60p PMH4/2N1 4-way harness (16•34 BNC plugs. 70p 08/70cm. el. slot . (15-47 (11-50 PBM 18/70cm. parabeam E18-56 111-50 JAYBEAM KR400 supports ton JAYBEAM 9502 ideal for VHF. S0239 joiners 859 costs (95 inc. VAT. £150 (only needs 3 core cable). MBM48/70cm. multibeam 121•65 112• 00 4 p,n mic. plugs 84p AN ABSOLUTE BARGAIN! E1.50 carriage MBM88/70cm. multibeam E28•97 IC2-00

WE ARE THE UK's COMPLETE HAM RADIO CENTRE MAIL ORDER Et RENTAL SALES: WATERS Et STANTON ELECTRONICS, 31, SPA RD., HOCKLEY, ESSEX TELEPHONE HOCKLEY (03704) 6835 TELEX 897406 TELEPHONE CREDIT SALES WELCOME PART TIME AGENTS G3XTX (0708) 78956 GM3GRX (03241 24428 G3P WJ 1038441 77778 G3WRA (0432) 67864 G3N MU 102721 669954

RADIO COMMUNICATION May 1979 393 (nnlie ) Lic[ccif

1-111Li 7r)1CL)9M WHY SETTLE FOR ANYTHING LESS? The TR7500 is still the commonsense two-metre FM mobile ng, employing as it does the straightforward channel number display which reads 20 for S20. 7 for R7 and so on, with no six-digit frequencies to remember and straightforward fast access to any channel within the two-metre band 144-146MHz. A scanner unit is now available from M.R.S. Communications Ltd (see address section{ to further expand the TR7500 facilities.

The sharp eyes will notice that the mode switch is now different on the TR7500, having four, not three, positions (marked 4. 5, N. RI and we are finding that the TR7500 Brief Specification current equipment seems to have higher transmitter power and an improved receiver performance. Inevitably, people are calling this the TR75008 but it's Frequency range: 144 146MHz really a case of a production improvement. SO B it) Channel spacing; 25kHz (other spacings availablel Why not call at your nearest authorised Trio dealer before you consider buying a Repeater shift: + or - 600kHz (1-6MHz available) two-metre FM mobile and ask to see the TR7500113)7 Take the lid off and Power output: Nominally 15-18 W see what good engineering design looks like in the unbeatable TR7530 from Trio. RX sensitivity: 12dB SINAD for 0.7.i.N or less Tone burst: 1750Hz tuning fork. Automatic in repeater mode Price: £235 Inc. VAT * STOP PRESS NE WS * SO ME L'=) ( ) M RI Cb PEAK PORTABLE PERFORMANCE PRICES ARE DO WN CONTACT US FOR DETAILS .11 E-2J

e. MULTU M IN PARVO

q e,\ _ teir-10-7.4.1 70cm FM repeaters are now so numerous and so umeitseg. efficient that its almost possible to go anywhere in • the country and still be within range of one. As • e"-• •' • ••— • many operators are finding, you don't need high power to be successful, and the TR3200 70cm portable/mobile rig provides the perfect solution to the 00\4Se search for a go-anywhere rig. c.) in,...,f.ata We • soery The TR3200 power output is two watts or more. swachable to 400m W, it has a really good receiver, a high gain I whip antenna and top performance under all conditions. Use it portable on the internal .• e battery pack or mobile using an external antenna and power from the car. Supplied with three chan- III M I nels fitted, carrying case, shoulder strap and all accessories, the TR3200 is the complete 70cm FM answer. Drop us a line and ask for full details, or better still, We introduce yet another exciting innovation from formance IF. system for his uansverters. come along and see the TR3200 and all the Trio Trio in the new TS120V HF transceiver. Equally at range in comfort. home in mobile or home station situations, the The transceiver is based on an advanced PLL T5120V packs more features into a small package system and the digital readout gives you the cor• than any other comparable model. recr operating frequency at all times unlike many other rigs. Remember my previous com ments Measunng only 9 'h r 33:" x 9 '4' -which is about Trio attention to detail! * NEW * about the size of a packet of cornflakes, the 5- BAND 80-10m VERTICAL TS120V can best be described as a miniature For case of operation. the 15120V is unsurpassed: TS820. The rig covers all bands 80- 10 metres-and simply select the band required, tune the VFO to NO RADIALS REQUIRED all of 10 metres 28-30 MHz so it's ideal for the frequency you want and there you are: no transverter driving, has digital readout built in, vox, preselector or PA tuning to worry about. and 8 ON GROUND POST break-in CW. RIT, noise blanker and the unique distinct safety feature for the mobile operator. Trio passband tuning system used in the 820. The PRICE : power output is 10W and a matching linear will be We at Matlock, have all fallen in love with the HF5 VERTICAL £40.50 along shortly. TS120V and we feel sure that you will too. At its The TS120V is cleady a winner for mobile operation price of £4.15 including V.A.T. land including digital inc. VAT but is equally attractive at home and is perfect for readout, vox, etc) we have no doubt that this trans- the VHF/UHF enthusiast who requires a high per- ceiver will be another winner from Trio. See it soon.

FOR FULL CATALOGUE SIMPLY SEND 40p IN STA MPS TO MATLOCK

394 RADIO COMMUNICATION May 1979 P- . n1 \vie - L, • ,,) k__ . l 3 r`— ?..1 P-icuo,,,, , 4.m lEzI o , 1 . -- , (,) 1

_ [-( 19 Cr-l i) • Te11 .1111 11 " 1111 . '-'4------4ie ; • i I 14, • • • ' 2 METRE SYNTHESIZER I di PORTABLE •-"••••, > The TR2300 is a really remarkable package which combines all the advantages of a portable station with those of a sophisticated Work real DX with ease on two-metre SSE and CW. The TR7010 combines a high performance receiver with a 10 Nir...... _e bro. mobile set. With the Ta2330, you get full band coverage from 144-146MHz in fully synthesiz• Watt transmitter and provides mobile or fixed station cd 25kHz channels together with 600kHz capability at low cost. r • , . repeater shift land reverse repeater if required) Supplied ready to operate from 144•1-144.34MHz, the - I/ with automatic 1750Hz tone burst. TR7010 covers all CW, SSE and beacon activity. 48 chart- nefs with 5kliz spacing plus VXO and RIT provide con- I 4,1 The dial is directly calibrated in frequency and tinuous coverage. r • has switched illumination for ease of use at Operation in any other part of the two-metre band can be I night and also in mobile situations. carried out by a simple crystal change and no re-alignment is ,I The transmitter puts out a very clean signal in- required. deed at a power in excess of one watt, and the Single conversion using an IF of 10-7MHz with a first-class receiver is very sensitive, in fact better than crystal filter gives outstanding selectivity. Wide range many big rigs. Using the external power and amplified AGC and newly developed FET devices in the RF $ external antenna sockets allows one to use it and mixer stages allow maximum sensitivity to be used with ; as a fixed station when desired, freedom from overload due to adjacent signals. I The single conversion transmitter using fully balanced mix- , The TR2303 is amazingly small, much smaller ers generates a beautifully clean signal with crisp audio ; than it's predecessor the TR2200GX and uses quality. . a more sophisticated case design and modular Join the SSE gang and work real DX for £189. Send for full . construction making a really rugged rig. It. details now. •. comes complete with carrying case, shoulder ;I strap, battery charger, external power cord, 1 etc. Needless to say, you don't need any VERY SPECIAL PRICE # •,, .41, / crystals! For further information, please do not hesitate TS7005 to contact your nearest authorised Trio dealer. CONTACT US FOR DETAILS

SURELY THE j 4 MOST AMAZING_ HAND-HELD -- TRANSCEIVER YET! FRO M A. O. R. . ' The AR240ss a truly staggering rig. In a small hand- held unit you have a fully synthesised 2 metre FM FULL COVERAGE 144 148M Hz transceiver covering 144-148MHz in 5kHz steps. Frequency selection is by direct reading top CHANNEL SPACING 5kHz --,leekvi mounted decade switches giving instant access to any frequency in the tuning range. Power output à FULLY SYNTHESIZED over IW and the receiver sensitivity is not only ex• + 600 and — 600kHz SHIFTS ceeent, it's maintained across the full tuning range by automatic vohage controlled tracking. Both up 1750Hz TONEBURST eir and down 600kHz repeater shifts are built in anisa 1r" 1750Hz tone burst. 1} WATT OUTPUT What more could you ask for in a hand held, ex cept possibly a price of £196 including VAT?

WHO'S WHO IN THE TRIO FACTORY-BACKED SALES Et SERVICE GROUP Not all dealers sell Trio products... and not all dealers who sell Trio products are authorised Trio dealers. By buying your Trio equipment from an authorised dealer, you can be confident that you have the support of the Trio service and back up organisation stretching all the way through your distributor right back to the factory. Only an authorised dealer can give you the service, spares and advice that you may need, and only an authorised dealer can allow you to take advantage of the regular meetings between the distributor and Trio factory personnel at which there is a constant exchange of infoimation and advice. The official Trio organisation in the United Kingdom is shown on the next page.

HEAD OFFICE AND SERVICE CENTRE 119 CAVENDISH ROAD, M ATLOCK, DERBYS. TEL: o629.2e17 or 2430. TELEX 377482. OPEN 9 5.30 TUES SAT. PHONE IN 9am-9p m. Agents: John. G3JYG, 16 Harvard Road, Ringmer, Lewes, Susses, Ringmer 612071. Sim, GPA3SAN, 19 Ellismuir Road, Eiaillieston. Nr Glasgow. 041-771 0364 FOR FULL LIST OF AUTHORISED DEALERS AND AGENTS SEE NEXT PAGE

RADIO COM MUNICATION May 1979 395 'T Ft' Co M ODEL OF THE MONTH — THE BEST IN HA M RADIO r-r Fe. I 0

2 METRE SYNTHESISED FM PORTABLE

The TR2300 is a really remarkable package which combines all the SEE THE TR2300 advantages of a portable station with those of a sophisticated AT ALLY-PALLY mobile set. With the TR2300, you get full band coverage from 144-146MHz in fully synthesised 25kHz channels together with 600kHz repeater shift (and reverse repeater if required) with automatic 1750Hz tone burst.

The dial is directly calibrated in frequency and has switched illumination for ease of use at night and also in mobile situations.

The transmitter puts out a very clean signal indeed at a power in excess of one watt, and the receiver is very sensitive, in fact better than many big rigs. Using the external power and external antenna sockets allows one to use it as a fixed station when desired.

The TR2300 is amazingly small, much smaller than its predecessor the TR2200GX and uses a more sophisticated case design and modular construction making a really rugged rig. It comes complete with carrying case, shoulder strap, battery charger, external power cord, etc. Needless to say, you don't need any crystals!

For further information, please do not hesitate to contact your nearest authorised Trio dealer.

SPECIAL ANN OUNCE MENT Due to overwhelming demand for the TR2300 worldwide, Trio have doubled their production output and have been able to reduce the price to you. Price now including VAT is £195

All Trio equip ment is available fro m the follo wing authorised Trio dealers LOWE ELECTRONICS LTD, 119 Cavendish Road, Matlock, Derbys. Tel: 0629 -2430 or 2817 NOTE: THE R300 RECEIVER IS ALSO AVAILABLE FRO M PARTRID GE ELECTR ONICS LTD.

WILTSHIRE YORKSHIRE W ALES BIR MINGHA M PACE ELECTRONICS LEEDS AMATEUR RADIO M.R.S. COM MUNICATIONS LTD WARD ELECTRONICS 9 Lime Kiln 27 Cookridge Street 76 Park Road Soho House. 362 364 Soho Road Wootton Bassett, Nr SWINDON LEEDS LE2 3AG Whitchurch, CARDIFF BIRMINGHAM 821 90t. Tel. Nos. Charles 107931 850056 Telephone No. 0532 452657 Telephone No. 021 554 one Phil 107931 771153 Tel: No. 0222 616936

LANCASHIRE SOUTH LONDON NORTH LONDON W HY DON'T YOU STEPHENS-JAMES LTD COMMUNICATIONS HOUSE RADIO SHACK LTD TRADE UP TO 47 Warrington Road 20 Wallington Square 188 Broadhurst Gardens LEIGH WALLINGTON SM6 8RG LONDON NVV6 3AY Telephone No. 0942 676790 Telephone No. 01-669 6700 Telephone No. 01 624 7174 'T RI O

Any other firm offering Trio products is not an officially authorised Trio dealer and Trio equipment purchased from such a company is not backed by the Trio service and spares organisation in the U.K.

396 RADIO COMMUNICATION May 1979 4 0 ;ilbilehNis..‘ Opposite South Harrow Tube and Bus Stations NEC MILS\ Cl_ A MCO M M SERVICES 194A Northolt Road eiYAESU FDK South Harrow, Middx *II/Pee re, London. Tel: 01-864 1166 \\,..../ - ROTATORS RF PO WER METERS YAESU PRICE LIST (inclusive VAT & Carriage', STOLLE 2010 .. .. £48.50 .1D 110 tû& 100w .. .. £11.88 HF Equipment FL 110 • £,,,,..144 •,,t0 AR 30 VHF/UHF .. .. £47.50 Reace UH74 432/144 .. .. £15.28 FT 901DM FR 1015 • • • ‘.,,,'.";•,,,,'•"' AR 22 VHF Light HF .. £49.50 Hanson 20/200w-150Mhz £26.50 FT 901D FR 101D • • • • '"•"'" AR 40 VHF Light FIF .. £54.50 Leader LPNI 885 20/ 200/ 1Kw £55.08 FV 901DM f24000 FR 101DD .. ‘..,,,,,£685...,„ 00 AR 33 AR40 De Luxe .. £67.00 SWR 25 Twin 3.5/ 150Mhz £11.90 SP 901 FRG 7 • ""'"' CD 44 Heavy duty . .. £108.00 Leader LPN1 880 absorption watt • FTV 901 £245.00 FRG 7000 • • £,.....3re e2 Ham Ill Heavy duty .. £156.00 meter 5.'20/120w 1.8-500 £85.00 FC901 .. .. E129.00 FT 7 - • `"'•uu KR 400 HF Inc. VAT & Delivery Y0901 £260.00 FT 78 .. .. £421.00 DR 7500 HF .. .. £106.00 FT101Z .. £562.00 KR 9502A VHF .. .. £46.00 FT101ZD VHF Equipment Bearing CD 562 .. £7.80 JUST TELEPHONE YOUR CARD NUMBER OR FT 101E .. .. £569.00 Fl. 225RD .. £1300.00 Bearing RZ100 Stolle ..£12.00 SEND YOUR CHEQUE WITH ORDER FV 101B .. .. £95.00 FT 225R . . £545.00 Incl. VAT & Delivery SP 1018 .. .. £21.00 Memory £104.00 FL 2100 £345.00 FT 227R £227.00 Access [BARCLAYCARD] yo 101 .. £190.00 £575.00 CPU 2500RFT 227RA .. £255.00 I C O M FT 301 .. £26.00 j a bh„ VISA FT 3010 .. £656.00 CPU 2500RK .. £345.00 Full range in Stock 1111I MOrkia FT 30150 .. £590.00 CPU 250ORS . ,..,.,,,,,,£295.00 £810.00 FC 301 .. £120.00 CPU 250ORKS • ''''''''''' C 701PS ...... 036.00 FY3°1 .. f105.00 FT 202 00 01-864 1166 01-422 9585 £99 • C 211E ...... £530.00 C 245E ...... £393.00 C280E .. .. £265.00 MICRO WAVE MODULES Full range ot Accessories Available C 240 .. £185.00 MMT 144r Any IF .. 038.00 C 202S .. £20500 MMT 432/Any IF .. £109.03 C215 .. .. £169.00 MMT 432/28S .. £133.80 C 402 UHF . ..£270.00 MMT 432/144 .. £149.60 C RM3 ...... E94.00 MMT 432/144R .. £169.80 DAI 007 C SM2 ...... £2450 MMV 1152 /Tripler Var. £34.80 Inc. VAT ft Delivery MMV 1296123cm Triplet...... £33.70 MMD 050/500 DFM to 500Mhz £63.00 10 CHANNEL MMC 144/Any .. £20.25 MMC 144/28 LO .. £20.25 MMC 70/Any £20.25 SCANNER , FDK MMA 144 Preamp .. .. £14.60 MML 144/100 Linamp .. £139.50 Multi 700E £229.00 MMC 28/144 multi in, .. £299.00 MMA 28 Preamp . , .. .. £14.63 2 Metre (144-146Mhz) FM 10 Channel Multi 2700 .. .. £499.00 Incl. VAT & Post TM 56B Rcyr 2m Scanning Receiver supplied complete amateur .. .. . £104.00 JAYBEA M TM 5613 Marine band. £113.00 2M Antennas with the following, SO, S20, S21, Incl. VAT Et Delivery 5Y i2N1 5 el yagi .. £9.66 SY:2M 8 el yagi . £12.25 S22, S23, R3, R4, R5, R6 and R7. SMC MONITOR - 10Yr 2NI 10 el yagi .. £26.13 Nicad batteries, mobile mounting SCOPE £79 PBM 10/2M parabeam .. £30.75 incl. VAT PBM 14/2M parabeam .. £37.55 5XY/2M 5 el ad yogi .. £19.513 bracket and charger. DELIVERY FREE 8XY /2M Bel x'd yagi , £24.10 IOXY/2M 10 el x'd vagi .. £31.76 Dimensions: 69 x 112 x 33mm ANTENN A PMH /2C circular harness .. £6.15 04/2M 4 el quad .. £20.17 Weight including batteries 230g TUNING UNITS C16/2M Eel quad .. £26.70 Amtech 300 1.5/30 Mhz £37.50 DS/2M el slot . , £17.00 Price £77.50 inc. VAT Et Carriage. SST 1 Random Wire D8/2M el slot .. £Z2.20 1.5-30Mhz .. .. £24.40 UGP/21V1 ground plane . , £8.58 SST 2 Ultra Tuner SVMK /210 vertical slot 3-5 •30Mhz .. .. £33.50 H0/2N1 halo head f4.20 SST 3 Mobile Match £14.90 Q M 70 tax paid everywhere HM/2N4 halo mast f4.98 po.tri SST 4 ATU/S WR/P WR PMH2/ 2M 2-way harness £3.10 70/28RC 4m -10m cony...... £18.46 I .8-30Mhz 30w.. .. £49.50 PMH4/2M 4way harness . £18.94 144 /28FIC 2m-10m cony. : . ' ' ...... £18.46 Dentro MT30:0 £26.99 10 • 160Mhz 3kw £365.00 70cm Antennas 432 /144RC 70cm-2rn cony...... £26.99 Leader LAC 895 500w PBM18/ 70cm Parabeam £....,..,•2.2 53 434128RC 70cm-10m cony...... £26.99 SWR/PWR/ATU £103.00 MBM48/70cm Multibeam ,,....,...._`"P-£0 434/ 144FIC 70cm-2m cony...... £2639 Incl. VAT Er Delivery M BMW/ 70cm Multibeam • • L.„C .,,,.e 432 +434/213 two band 70cm• 10m cony...... , £3233 XTAL FILTERS 12XY / 70cm 12 el x'd yagi - ' • • T.4.'„•,,?5, 432 +434/144 two band 70cm-2m cony...... £3233 YF 90H12 ...... £13.60 PMH2/70cm harness • • .-....' 144PA 10/40P1OW in 40W out linear amp with preamp .. .. £59.00 YF 30H350 .. .. £13.50 PMH4/70cm harness .. .. £14.35 144PA2 /45 2W in 45W out FM Amp wkh preamp £7025 C 8 e 70cm 8db colinear .. £46.03 YF 90H2.4 .. .. £13.50

SECURICOR - HIRE PURCHASE -ALL EQUIPMENTS SERVICED

RADIO COMMUNICATION May 1979 397 A NEW RIG?? You can't beat Western for VALUE . . . \/VAESU You can't beat Western for CHOICE . . . ( YAESU FRG-7000 £329 The New Performance Standard in Communications receivers! A high quality general coverage receiver for the discerning SVVL and a worthwhile addition as a second receiver for the transmitting amateur. How often have you wanted a true general coverage receiver of this calibre but been put off by the price. :..0111F4 . - _ The FRG-7000 le a costeffective answer to your prayers. • * Full and continuous coverage 250kHz to 29.999MHz * Operation on SSB/AM/C W * Switched selectivity and fine tune control for maximum efficien. cy on SSS * Accurate digital frequency readout to 1kHz, using advanced CPU techniques * Built-in digital clock with facilities for setting two time zones (GMT /7-«\ fir and local). selected at the flick of a switch * CPU controlled timing clock switches receiver on or off at preselected times; also enables control of external unit such as tape recorder * Wadley loop circuitry for minimum drift and maximum stability 11— * Simple and accurate frequency selection; easy-to-use colour coded bandswitch and pfflelector.

\ YAESU FRG-7 £199 The general coverage receiver for the SWL with a limited budget. Good all-round performance at a down-to-earth price.

* Full and continuous coverage from 500KHz to 29-999MHz. * SSB/AM/C W operation. * Fine tune control for ease of SSS tuning. * Accurate readout of frequency to 10KHz or better, using MHz and KHz controls. * Wadley loop circuitry for minimum drift and maximum stability. * Operation from mains supply, internal batteries or external 12v DC.

OTHER W C ACIrn PRICES An Invitation FT-101E (while stocks last) £559 We at WESTERN have great pleasure in inviting you

FT-901DM £949 to Our FC-901 £122 10th Birthday 'AT HO ME' DAY FT-225RD £584 FT-227R £230 Saturday, 19 May 1979, from 1000 to 1700 FL-2100B £336 mlection of equttuncnt on 41Émonstration CPU-2500RK £335 *• Tonyn, masts and antennas for inspection * Refreshments available PHONE FOR DETAILS OF THE * No obligation ro buy, fuir a friendly social us-carton to mea the folks or Louth, but please feel free to press rash into our hands of you cis's! EXCITING NE W FT-101Z * mi S22 from 0900. and FT-101ZD!

FREE DELIVERY and TWO-YEAR GUARANTEE All prices include VAT at 12 -°/ci

ACCESS — BARCLAYCARD — DINERS CLUB — HP ARRANGED

398 RADIO COM MUNICATION May 1979 Electionics (1111) ltd WESTO WERS THE CHOICE OF /TRIO TS-120V MATCHING PSU —PS20 £59 PROFESSIONALS . Trio's latest for HF Mobile are in use World-Wide by: Join in the mobile scene now that conditions are up! • IN rig features in a compact package * The Amateur who appreciates the s Digital frequency readout ✓ All bands 10 to 80 metres CW/SS8 • 10 watts outp-r: Best! * BBC * British Rail * MOD • IF passband tuning and other line features (Army) * Foreign Governments and COMING SOON —TS-120S 100 watt MODEL! j Professional Com munications Com- panies. («TRIO TS-520S £549 N\ WESTO WER . . . CHOSEN for its: Yet another Trio bargain from WESTERN! The latest version of this fine HF Transceiver with all the up-to-date features needed by HIGHER STRENGTH— rated headloads up to todays amateur but at a realistic price. No frills, just good all-round 75rnph (Standard) and 100mph (Heavy•Duty) performance and excellent value at the price. FULL DATA published on loads and wind- Full coverage 10-193 metres. CWISSB All solid-state except driver 112BY7A1 and PA which uses rugged arid speeds — no guessing as to capability proven 61468 IS-2001A) valves HIGHEST QUALITY welding and workmanship Improved speech processor to help In :hose pile-ups SUPERIOR and UNIQUE 'FBP' Framed Base (see Highly efficient noise blanker below right) RAPID AVAILABILITY—All models available from (-TRIO TS-820S stock Iba pacesetting 10 150m Transceiver for the amateur who wants to NO HIDDEN EXTRAS—prices carriage paid keep up•to-the-minutel Loaded with features to make your mainland except some areas, which are clearly operating even more enjoyable; among these are: * Advanced PLI. cacuary and ultra-stable VEO for accurate and shown below spurious-free frequency control WIDE RANGE—Heights from 25 to 75 feet (Stan' * Factory-fitted digital readout of TRUE frequency—NOT just a "VFO dard) and 42 to 107 feet (Heavy Duty). counter" hke some others Speech processor gives true RF compression; from panel controlled and fully metered TECHNICAL DATA IF shift to çombat ORM on a busy band STANDARD RANGE Model 1$ 2S 3S 4S Height 2511 4211 58ft 75ft Headload 515tb 265th 125Ib 35th 1500.04 TRIO TL-992 £819. PRICE £241.92 £322.92 £419.04 Loads are for unguyed towers at 75mph windspeed. Want a BIG LINEAR? This is ill Guyed loads are 88011,11S). 6001bI2S. 3S), 3301b14S1 A real powerhouse to complement your station, only needs BO HEAVY DUTY PRICES SHO WN watts drive for full output. Model 2f-ID 3HD 1 41-ID ARE FOR FBP 2000 watts PEP input SSE; 1003 watts CW/RTTY Height 4211 58ft I 75f t MODELS AND 2x Ermac 3-500Z in AB2 grounded-grid for cool efficiency Headtoad 36015 14515 261b INCLUDE VAT * Blower switch-off delay and full safety Interlocks PRICE £420.12 £513.00 I £617.76 AT 8% Loads are or unguyed lowers at 100mph windsoeed. Guyed loads are 8801b121-4D, 3HDI, 6001b14HD1. TRIO VHF EQUIP MENT 5HD19110 and 6HD1107fti, guyed only models available

TR-2300 £189 Fully synihesrsed 2m FM portable, 25kHz channels, excellent value Due to distances involved, carriage is extra for: DEVON, SCOTLAND (S. of Pitlochry) £54.00 TS-700S 1599 All-modes on 2M, digital frequency readout, built-in swachable Rn prearrp. CORN WALL, SCOTLAND IN. of Pitlochry) mains and DC operation. £86.40 inclusive of 8% VAT.

PHONE AFTER HOURS AT CHEAP RATES! Use our message system to request info or place your order.

Our Agents Southern. Alan Paxton, G4B1Z. Southampton. Hants Wuton Electronic/ (UH) ltd (07031 552182 Scotland: Alen Cameron. GM3OGJ, Allua (02591 214663 N Ireland: Les Lyske. GI3CDF. Newtownards 10247) HEAD OFFICE (All M'ail/Enquiries1 812449 FAIRFIELD ESTATE Opening hours. LOUTH, LINOS, LN11 OJH LOUTH. 9 12; 1 Spm Mon Fri. By appointment Sat 9 12. LEICESTER: May's HI-FI, Churchgate (Tel: 0533-588821. Tel Louth 10507) 4966 ,6 Mon Sat 9 6pm; closed Thurs.

RADIO COMMUNICATION May 1979 399 AEUK Your number one AS FACTORY APPOINTED DISTRIBUTORS WE OFFER YOU - WIDEST CHOICE, LARGEST STOCKS, PRO MPTEST DEAL AND FAST, SURE SERVICE RIGHT THROUGH -

PLUS EX-STOCK DELIVERY OF THE FABULOUS NEW FT-101Z AND FT-101ZD, THE LATEST HF BAND TRANSCEIVERS FRO M YAESU MUSEN. NEVER BEFORE HAS THE RADIO AMATEUR BEEN OFFERED SUCH SOPHISTICATED EQUIP- MENT AT SUCH REALISTIC PRICES—JUST STUDY THE CONDENSED SPECIFICATION BELO W AND YOU'LL FIND FEATURES AND VER- SATILITY ONLY AVAILABLE ON MUCH MORE EXPENSIVE RIGS —CALL, PHONE OR WRITE FOR FULL DETAILS (PLEASE SEE FACING PAGE).

FT101ZD Series High Performance Transceiver FULL COVERAGE RF SPEECH PROCESSOR VARIABLE IF BAND WIDTH DIGITAL PLUS ANALOG Full band coverage is provided on A high-performance RF speech Using two 8-pole crystal filters READOUT the FT-101ZD: 160 through 10 processor is built into every FT- with superior shape factors, the The FT-1012D features digital meters, plus W WV!..UY recep- 101ZO, providing an increase in FT-101ZD variable bandwidth plus analog frequency readout. tion on 5MHz. Teamed with the your average talk power of ap- system is a valuable tool on The display features big, bright FTV-901R transverter, operation proximately 6dB. The processor today's crowded bands. With the LED digits, for maximum can be extended to 50, 144, and level can be adjusted from the turn of a dial, high-pitched SSB readability. For extra savings, the 430MHz from your desk top. front panel, for optimum signal "buckshot," or unwanted CW economy model FT-101Z gives enhancement. signals, can be eliminated from you the same precision analog CLEAN OUTPUT SIGNAL W ORLD-WIDE POWER the IF oassband. display, at a significantly reduced With today's crowded bands, we CAPABILITY Compare for yourself: other cost. You can add the digital all have the responsibility to keep The FT-101ZD has provision for systems use a single filter in the display later, if you wish, our transmitted signal free of operation irorn a variety of AC IF; though you can move away spurious radiation. YAESU voltages, from 100 to 234 volts. from one interfering signal, you engineers have included RF When you're travelling, you'll may move into more CIRM. The INTERFACE WITH 901 negative feedback, for a clean never need a heavy, bulky YAESU design actually varies the SERIES COMPONENTS output signal. transformer for operation with bandwidth, eliminating the ORM. Your FT-101Z0 may be used with your FT-101ZD. A DC-DC con- Other manufacturers would have all of the exciting FT-9010M STATE OF THE ART NOISE verter is an available option, for you spend hundreds of pounds series accessories. The PV- BLANKER mobile operation. The FT-101ZD on different filters for 2.1kHz, 9010 M synthesized, scanning The all-new noise blanker is extra- is small enough to qualify as 1.8kHz, 1.5kHz, 800Hz, 503Hz, VFO provides storage and recall ordinarily helpful in reducing the carry-on baggage on most etc. With the FT-101ZD, you have of up to 40 frequencies, in addi- level of impulse noise. The blank- airlines, and is equipped with a continuously variable band- tion to its 3-speed scanner and ing level may be adjusted from the strong, side-mounted handle for width—from 2.4kHz down to auto scan function. Sae for infor- front panel. ease of carrying. 300Hz. mation on other accessories. HOW TO REACH US (EASY PRIVATE PARKING ON OUR 70ft. FORECOURT) FRO M SOUTH AND EAST. We are located approximately two miles 'ram Junction 5 of t ne M6 from which follow signposts ro Birmingham Within mile turn right at Clock Gaiage and proceed towards City After one mile look for traffic lights at Foe & Goose and immediately over the lights rake minoi left fork into Aiom Rock Road We are located one mile from this point FRO M NORTH. Leave M6 al Junction 6 (Spaghetti) and follow left lork down to traffic island beneath motorway complex Take third turning off to Lick? ield One mce further on follow 44040 to the right and within 100 yds veer again to the right. approximately one mile further on brings you to the Fox & Goose Turn right and see preceding directions FRO M THE WEST AND SOUTH/WEST. Follow M5 then M6 to Spaghetti Junction (seeabove) Alternatively. leave M5 at ;unction 4 Or 3 and proceed to inner ring rind Turn South )rt ring road and leave on 447 (East) We are located Ihree miles from this point

Hours: 9.30-5.30 Continuous including Saturdays —Early closing Wednesday, 1 p.m.

Arc ,,s Access or attractive H.P. terms readily available for on-the-spot transactions. Full demonstration facilities. Free Securicor delivery.

400 RA DIO CO M MUNICATION May 1979 AMATEUR ELECTRONICS UK source for IFAESU MUSEN

TYPICALLY, YAESU HAVE NOT OVERLOOKED THAT VERY IMPORTANT GROUP OF OPERATORS—THE DEDICATED SWL's BY PROVIDING THE SUPERB VALUE-FOR-MONEY FRG-7 AND THE ULTRA SOPHISTICATED FRG-7000 GENERAL COVERAGE RECEIVERS. YAE-SU

Here's a 10-1 winning offer if you'd like the full Yaesu catalogue. Just send us 4 x 9p stamps I36p) and we'll send you Yaesu's fully illustrated brochure together with our Credit Voucher for £3.60 against your eventual purchase. A couple of stamps will bring you the FT1012, Atlas or Swan leaflets or our current used equipment list.

NEW! ADVANCED TECHNOLOGY fromELECTRONICS level 100 WATTS MINIMU M OUT!

dd i 1 OOMX —THE DE-LUXE M OBILE RIG WITH ALL THE EXTRAS Solid state HF transceiver. 100 watt PEP and CW output, 80M 10M. Broadband design featuring noise blanker. VOX, 25KHz calibrator, CW sidetone, semi-break in CVV. RIT, built-in speaker. Ultra stable PTO frequency source. Operates directly on 11 to 15 VDC, USB, LSB, CV'.! operation.

I 9MHz 8 pole crystal IF filter. 4W Audio 0/P. UNBEATABLE PERFOR MANCE—UNBEATABLE VALUE £459 PLUS VAT THIS IS THE RIG FOR THE MAN WHO INSISTS ON THE BEST

AS DIRECT IMPORTERS AND MAIN AGENTS WE OFFER THE it • 'Et ATLAS FAMOUS ATLAS 210X and 215X TOGETHER WITH ALL AC- R A DI O INC. CESSORIES FROM STOCK,

BRANCH: AMATEUR ELECTRONICS, UK -- COASTAL, CLIFTONVILLE, KENT, KEN McINNES. G3FTE, THANET (0843) 291297. 9 a.m.-10.30 p.m. BRANCH : AMATEUR ELECTRONICS UK SCOTLAND, 287 MAIN STREET. WISHA W, LANARKSHIRE, GORDON McCALLU M, GM3UCI. TELEPHONE WISHAVV 71382. (EVENINGS CAR(UKE 70914) AGENT: W ALES & WEST—ROSS CLARE, GW3N WS, CAER LEON, NEWPORT. (CAERLEON 422232)—ONLY 20 MINUTES OVER THE SEVERN BRIDGE.

508-514 ALU M ROC K RO AD 1497 021-327 BIR MING H A M 8 Telex337045 63 "

RADIO COMMUNICATION May 1979 401 DEPEND UPON THE ORIGIN AL ASCOT ANTENNAS VERSATO WERS

This is a complete range of mobile antennae and accessories developed and manufactured in the United Kingdom. TELESCOPIC+TILTOVER All antennae are extremely rugged, designed to withstand extremes of weather using: fine stainless steel whips, A100 nylon bases, chrome-plated brass ferrules, heat-treated silver-plated beryllium copper contacts and polished stainless steel shock NO OTHER TOWER COMPARES springs. -THE MARKET LEADER

12 years development, over 50 models PICK THE TYPE (+A OdB 1+413dB) available with heights between 25-120ft. 3413 STANDARD BASE: 60-550MHz £1.90 Post, base plate, wall or fixed base moun- 1.À. 4 310 SWIVEL BASE : 60-500MHz £3.65 ting. Designed to latest BSS and for wind- 344 SPRUNG BASE : 60-120MHz £5.60 speeds up to 117 mph. Before purchasing a 4411 STANDARD BASE 145MHz £3.55 tower, we strongly recommend consulting ¡ A 330 SWIVEL BASE 145MHz £4.00 one of our engineers for advice regarding 341 SPRUNG BASE 145MHz £6.15 the most suitable combination for a par- STANDARD BASE 145MHz ticular installation. :.21_À. 350 FINE TUNE SASE 145MHz £6.40 351 SPRUNG 350 BASE 145MHz £7.75 THE STRONGEST YET SELECT THE WHIP (Stainless steel) LESS EXPENSIVE 051 121cm TAPERED: +, I, +¡ 10MHz £1.80 056 6.1.5an PARALLEL *A 144-432MHz £0.65 P4011 £276.75 +VAT EN CHOOSE THE MOUNT (Mag. Mount Et Assemblies c/w 4.5m Coax) P6fift £35.90 095 STANDARD CABLE ASSEMBLY MOUNT £1.80 STA N D AR D SERIES POST MOU NTIN G 1 or -5- 095 FIBREGLASS MOUNT TO S0239 £2.10 4 8 092 MAGNETIC MOUNT £9.45 +VAT 8% 084 STANDARD CABLE ASSEMBLY MOUNT £4.30 P4OHD £416.20 1 1 7,‘ 088 COWL MOUNT TO S0239 £4.65 091 MAGNETIC MOUNT £10.45 P6OHD £472.50 +VAT 8% ADD AN ACCESSORY HEAVY DUTY SERIES POST M OU NTIN G (Mounts fit all standard cable assemblies) MOBILE RANGE ALSO AVAILABLE 098 GUTTER CLIP MOUNT £4.50 093 BOOT LIP MOUNT £2.40 NEW 30FT • left SECTIONS 031 BLANK OFF COVER 1-A and itÀ £0.95 (144 BLANK Off COVER +A only

P30 £249 Capable of supporting a HE LIKE THE PRICES? THEN: BP30 £269 beam or several VHF Ants. The ADD VAT 12}% , CARRIAGE (Long ants. 95p, Accs. etc. 50p) headunit accepts r tube and +VAT 8% provides for a rotator. Oper- Ascot antennas are available; mail order from SMC HQ in Totton, ation is easy with single winch personal callers to any branch (Leeds, Chesterfield, Woodhall Spa). +Carriage system. SMC agent or reputable amateur radio dealers throughout Britain. 1 SOUTH MIDLANDS COMMUNICATIONS LTD SOUTH MIDLANDS COMMUNICATIONS LTD

OSBORNE ROAD, TOTTON Telex: 477361 SMCOMM G OSBORNE ROAD, TOTTON Telex, 477351 SMCOM M G SOUTHAMPTON SO4 4DN Tel: Totton 104216) 7333 (3 lines) SOUTHAMPTON S044DN Tel: Totton (00216) /334 13 Imes)

402 RADIO COMMUNICATION May 1979 KYOKUTO © KYOKUTO DENSHI COMPANY LIMITED © INKDK1 FM21:116E 2m FM DIGITAL SYNTHESIZED TRANSCEIVER

lar n n n n H LI

The KDK FM-2016E is a 12V DC two meter FM transceiver Dual-gate MOS-FETs are used for the RF and mixer to pro- for mobile and base station use. Using the latest CMOS IC vide superior inter-modulation characteristics with sen- digital PLL circuitry. It has been compactly designed with sitivity, held constant across the wide frequency range emphasis on maintenance and ease of use. covered, by automatic electronic tuning. Ax 144000 148.995MHz and Tx 14/1•000- 145. 995MHz. A monolithic crystal in the first IF and a com mercial quality Direct readout of operating frequencies by large size LEDs. 15-pole ceramic filter in the 2nd IF provides extremely sharp The most commonly used, 100kHz and 10kHz, switches selectivity. The 2nd IF is built with discrete components to are mounted coaxially. These will not go below the 0 or keep stray coupling to a minimum and a ceramic above 9 position facilitating frequency changing by feel only, discriminator has been adopted for excellent temperature for "eyes-on-the-road" motoring and use by those with im- stability and long-term alignment. paired sight. The RIT (Receiver incremental tuning) and centre zero An electronic memory using CMOS RAMs (Random ac- meter are useful for contacts with off-frequency or drifting cess memory ICs drawing only 25nA!) allows any four out of stations. the 1,000 channels to be written-in (stored) at a flick of a The single conversion transmitter uses a balanced mixer, switch. An auto-charging back up NICAD battery maintains five stages of electronic tuning, and a four-stage low pass the RAMs contents after disconnection from the power. filter for a clean, spurious-free signal. + .6 and - •6 positions of the mode switch provide for The ultra-modern silicon transistor in the final will survive normal repeater operation. In position 1T-2R the set Tx's on even an infinite VSWR. the frequency in memory channel 1 and Rx's on memory Power: HIGH (15 Watts) and LOW (1 Watt), is selectable by channel 2 (likewise the 3T-4R position). This provides for a front panel switch (useful with a linear). non-standard shifts, and is also convenient for use in con- Direct FM of the VCO results in superb audio. junction with up-converters. A two mode (burst or continuous) tone generator is ad- The memory may be scanned in the "closed" mode, (the justable from 1,750 to sub-audible frequencies. scanner will stop at the first channel in use) or in the 'open' A 5-pin "DIN" connector is provided on the rear panel for a mode, (stopping at the first empty channel). Scan-hold KDK SC-12A SELCALL (tone encoder-decoder) unit, allows transmission immediately the scanner stops. headset-microphone combinations or similar.

CALL IN AND SEE ONE IN YOUR LOCAL DEALER'S TODAY THE PRICE, £235+VAT (£264.37) inc. Securicor Delivery SOUTH MIDLANDS COMMUNICATIONS LTD S M HOUSE, OSBORNE ROAD TELEPHONE: TOTTON (042161 7333 TOTTON. SOUTHAMPTON CABLE: 'AERIAL' SOUTHAMPTON HAMPSHIRE SO4 4DN TELEX. 477351 SMCOMM G

RADIO COM MUNICATION May 1979 403 NNN \ South Midlands SMC IS 21! CELEBRATE WITH US UNICO M 21. JUNE 22nd Et 23rd Unique exposition and symposium on communications. Exhibition: The latest and best equipment. Quite a mouthful. But a date not to be missed. Demonstrations: Antennas, linears, towers. Venue: Kempton Manor, Sunbury-on-Thames. Lectures: The best-by the best. Time: Friday 6pm 12 midnight. Sat 10am 6pm. Features: Special draw, special vouchers. Bar and Buffet open throughout event. Full details next month of THE event of '79.

£88 + VAT INC. FT202R POST FREE FT202R £99 VAT Ex-Stock Now for under a hundred pounds inc, the handiest hand-held can be yours. Comes complete with: helical whip, tone burst, case, crystals S20, 21, 22. SELECTION OF CRYSTALS, EXTERNAL MIC/SPEAKER, CHARGER, POWER SUPPLY ARE AVAILABLE

£265.78 + VAT 12e/o INC. FT7 DELIVERY FREE FT7 £299 VAT Ex-Stock Now for under three hundred pounds the HF Transceiver that has them all talking. The big signal from a small package 10-80m, SSB Er CW CHECK OUR BIRTHDAY ARITH METIC-it's to your advantage

FT101E £515.00 FT101E £515.00 FT101E £515.00 FT101E £515.00 FTV250 £185.00 Y0601B £134.50 Y0101 £169.50 FV101B £85.50 VAT £87.50 VAT £75.13 VAT 77.93 VAT £75.06 £787.50 £724.63 £762.43 £675.56 Pay £691.87 Pay £676.57 Pay £721.93 Pay £640.12 Save £95.63 Save £48.06 Save £40.50 Save £35.44

FT301S £395.00 FT301S £395.00 FT301D £588.00 FT301D £588.00 Y0301 £167.00 FV301 £86.00 Y0301 £167.00 FV301 86.00 VAT £62.73 VAT £60.12 VAT £86.86 VAT £84.25 £624.73 £541.12 £841.86 £758.25 Pay £589.09 Pay £505.12 Pay £806.22 Pay £722.25 Save £35.64 Save £36.00 Save £35.64 Save £36.00

SPECIAL BIRTHD AY BON ANZA ALSO AVAILABLE ON FT101EE, FT301, FT301SD All normal conditions maintained, but subject to availability.

A SOUTH MIDLANDS COMMUNICATIONS LIMITED. G3ZUL Brian Stourbridge 03843) 6917 G GM3ZBE Alex Aberdeen 065183)3 e OSBORNE ROAD. TOTTON 4- 411 » Head Office. Showrooms E GM8GEC Jack Edinburgh 031665) 2420 SOUTHA MPTON, $04 413N Cables: Aerial Southampton N GI3WVVY Mervyn Tandragee 07621 840656 Hours of business Telex 477351 SMCO M M G G W3TMP Howarth Pontybodkin 0352871 846 DAY 9 5.30: Monday Saturday Tel Totton 104216) 7333 13 lines) S G W3TMP Howarth Pontybodkin 0352871 324 EVE

404 RADIO COMMUNICATION May 1979 Communications Ltd \e/ YAESU AR10 £29! SMC SCOOP BIRTHDAY BUY If you considered a rotator an expensive luxury before, think again. If you already use one, now is the time to motorise the iftet4,7J Hi -Fi or TV aerials. £29 inc VAT, inc post and packing (UK only) cannot be bad! (Rotor supplied c/w control unit and instructions)

H 12 1 ( L 8% ± CARR( " Rs [ Securicor delivery on foc.] ROTATORS + VAT P POST ite ms add £1.50 +

AR20 For small VHF ant, solenoid control E34.50 HSP foc ROTATOR ACCESSORIES AR30 As AF120 but solid state control f41.00 HSP foc HZ100 Alignment bearing. All Stolle E10.00 LSP £0.60 AR22 For medium VHF solenoid control £43.00 HSP foc CD562 Alignment bearing CDE AR20-AR30 £6.00 LSP £0.60 AR40 As AR22 but solid state control £47.50 HSP foc AK121 Kit, rotor to Versatower, CDE Bell type £3.60 LSP E0.40 AR33 As AR40 but 5 preset/man consols £59.00 HSP foc Casting mast mounting for Ham III £4.25 LSP £0.60 8T1 Medium duty 4 presetfman controls £79.50 HSS foc Hardware kit for above casting £6.30 LSP £0.40 C044 Medium duty continuous read out £95.00 HSS foc setea Hardware kit ¡replacement bolts, HAM Il Heavy duty solenoid brake £129.00 HSS foc clamps, CDE CD/TR44 HAM IM, Il, 1111 f6.40 LSP £0.60 HAM Ill Heavy duty solenoid brake £139.00 HSS foc 50425 Hardware kit 'replacement bolts, TX1 Very heavy duty rotator £199.00 HSS foc clamps] CDE AR 122-40-331 Bit £4.30 LSP £0.60 9502A Light duty small VHF/UHF Ant 145.00 HSS £1.15 Hardware kit Ireplacement bolts, clamps KR400 Medium duty-bell type 185.00 HSB £1.60 Stone all modets1 £3.60 LSP £0.60 H333 Heavy duty. Digital readout £iss.00 HSS foc (43.50 HSP foc 2010 "Automatic" through rotor type ROTOR CONTROL CABLE (Carriage extra or free with rotor) 2030 "Mernomatic" through rotor type £48.00 HSP foc 4 Way For AR 110.20-221 pr. yd. £0.20 LS 2021 "Sensor- Man 7 preset positions £98.00 HSP foc 5 Way For AR 130-33-401 pr. yd. £0.24 LS 2031 "Programmatic" 7 pos. cont, by tuner 185.50 HSP foc 8 Way For TR/CD44 BT1 HAM (M. 11.00 pr. yd. £0.36 LS

IF YOU WANT YOUR SIGNALS TO PENETRATE INTO NEW COUNTRIES

_ - -

TH6DXX TH3 MK3

W here Securicor delivery HYGAIN +VAT("Lie) + C A R I:1 ( pS pBoRsST ) is possible add U.70 + 8%

12AVO £37.50 HSB E2.130 10513A £92.00 H E3/813 DEI1015A £115.00 H E3.50 91486 £13.50 HSP £0.60 14AVO £52.50 HSB £2.00 153BA £62.75 H £3.00 TH2MK3 £109.75 H £1.50 LA1 E27.35 LSP £0.04 18AVT E76.00 HS8 11.25 155BA £117.50 H E3/130 TH3JNR [113.50 H £3.50 LA2 £3.45 LSP £0.30 14RMO £19.50 HSP E1.50 203BA £117.50 H E3/60 TH3MK3 £157.00 H E4.00 415 110.80 LSP £0.75 18V £27.80 HSEI £2.00 2O4BA £155.00 H E3/80 TH6DXX E205.00 H C3/80 499 (10.80 LSP C0.60 18HT 1225.00 H 8 E3/110 205BA £205.00 H E4/90 1-lY MAO £189.00 H E4.50 511 £3.135 LSP 10.75 10313A £51.00 HSB £2.50 402BA E158.00 H E4.00 417 £8.20 LSP [0.75

S.M.C. (Jack Tweedy) LTD NORTHERN (Leeds) BRANCH S.M.C. (Jack Tweedy) LTD Roger Haines. G3Y130 Colin Thomas G3PSM Jack Tweedy, G3ZY 79 Chatsworth Road 257 Otley Rond : Ham Shack. Houghton Lene. Chesterfield. Derbyshire Leeds 16. Yorkshire Woodhall Spa, Lincolnshire Chesterfield 102461 34982 Leeds 105321 782326 Woodhell Spa 105261 52793 9 5; Tuesday Saturday 9 5: Mon Wed Et Fri Sot. 9 5 Tues Sat 1+ appointments)

RADIO COM MUNICATION May 1979 405 YAESU MUSEN \e/

SOUTH MIDLANDS COM MUNICATIONS LTD OUR ONLY AMATEUR ELECTRONICS UK YAESU 508-514 ALU M ROCK ROAD SM HOUSE, OSBORNE ROAD, UK AGENTS TOTTON, SOUTHA MPTON SO4 4ON ALU M ROCK, BIR MINGHA M 8

- ALL NEW FT101ZD Digital Et Analogue Readout FT101Z Analogue Readout Version IS HERE NOW!

Any new piece of equipment from Yaesu is worthy of * Variable IF bandwidth 2.4kHz down to 300Hz note, one good enough to be called a '101' in line with * Digital plus analogue frequency display * RF speech processor—adjustable level • the world's most popular amateur transceiver, is an * Wide receiver dynamic range, with sensitivity event of the decade. The 'Z' series is a base station * Superb noise blanker—adjustable threshold design at its best, a no compromise, go anywhere (AC * Vox built-in and front panel adjustable PSU included, DC invertor option) unit of the highest * Semi-break in with sidetone for slick CW quality. The FT101ZD is an all new design using * 614613 pa's with negative feedback. 180WPIP * 160-10 metres plus WWV plus auxiliary band today's technology backed by a proud tradition. * Antennuator 0-10-20 dB front panel switch For further details of this exciting new unit please * AGC: Slow-fast-off, front panel switchable contact any of our authorised sales outlets, for a free * Clarifier (RIT) switchable on Tx, Rx or both colour brochure. * Selectable CW fixed bandwidths CW-W or CW-N

A full list of matching accessories is available to complement the FT101ZD. In the illustration below (looking from left to right) we have: the FTV901 transvertor (covering 4m, 2 and 70, with repeater shift etc. etc.) the FT901DM External VFO, (with 40 memory channels -±-50Hz stability AWU!!!) auto and manual scanning, the FT101ZD itself, the Y0901 monitor scope, which in addition to AF, IF, and RF monitoring offers panoramic (spectrum analyser) facilities. The FC901 Antenna Tuner /Power/S WR meter, and the SP901P external speaker with phone patch (Normal speaker SP901 available).

•

WORKING FOR OUR COMMON INTERESTS—at Yaesu Musen Amateur Radio equipment is not a sideline but the only business. Over 130 licensed amateurs proudly produce the most diverse product line available, SSB, CVV, AM or FM for mobile, portable or base use.

406 RADIO COMMUNICATION May 1979 COUNCIL President RADIO SOCIETY OF GREAT BRITAIN J. Bazley. G3HCT 35 Doughty Street, London WC1N 2AE Immediate Past•President D. S. Evans, PhD, BSc. FIM. G3RPE Telephone 01 -837 8688 Founded 1913 Member society. International Honorary Treasurer P. F. D. Cornish. FCA. G3COR Incorporated 1926 Amateur Radio Union Telecommunications Liaison Officer R. F. Stevens. G2BVN PATR ON: HRH The Prince Philip. Duke of Edinburgh. KG Ordinary members E. J. Allaway. MB. ChB. MRCS, LRCP, The national society representing all UK radio amateurs G3FKM P. Balestrini, TEng(CIE), MITE, G3BPT R. Bellerby, BSc, FBIS. G3ZYE Membership is open to all those with an active interest in radio experimentation and T. P. Douglas, MBE, AMIEE, G3BA communication as a hobby Applications for membership should be made to the general C. H. Parsons. GW8NP manager, from whom full details of Society services may also be obtained. R. F. Stevens. G2BVN G. M. C. Stone, CEng, FIEE, FIERE. G3FZL C. J. Thomas. G3PSM GENERAL MANAGER AND SECRETARY EDITOR Zonal members D A Evans, G3OUF A W Hutchinson Zone A. B. O'Brien. G2AMV Zone B. J. Anthony. G3KOF Zone C. D. J. Andrews. G3MXJ Zone D. L. Hawkyard. G5HD ANN UAL SUBSCRIPTION RATES Zone E. D. H. Adams, GW3VBP UK corporate: £8. including VAT Overseas: £8. Zone F. W. F. McGonigle, GI3GXP Zone G. G. I. Knight. GME1FFX Associates under 18: £3. Students aged 18 to 21: £4.50. (Student applications should give the member's age at last renewal date and include evidence of student status) REGIONAL REPRESENTATIVES Region 1-W. M. Furness. G3SM M Region 2-D. Smith, G4DAX Affiliated societies: £6.50 (including Radio Communication); £3.25 (excluding Radio Communication). Region 3-H. S. Pinchin. G3VPE Region 4-N. J. H. Grassby, G4CPY Region 5-R. E. G Kendall. G8BNE Region 6-F. S. G. Rose. G2DFIT Region 7-D. A. G. Pedder, G3LFX Region 8-0. N. T. Williams. G3MDO RSGB NEWS BULLETIN SERVICE Region 9-H. W. Leonard, G4UZ Region 10-R. G. Barrett, GW8HEZ The RSGB news bulletin, callsign GB2RS, is broadcast every Sunday morning on hf Region 11-P. H. Hudson, GW3IEQ and vhf, giving almost complete coverage of the British Isles. Its main purpose is to Region 12-F. Hall, GM8BZX provide an outlet for amateur radio news items and announcements which, by virtue of Region 13-A. B. Givens, GM3YOR their topicality or urgency, cannot wait for the next issue of Radio Communication. Region 14-1. McKechnie, GM8DOX The bulletin is prepared early on Thursday morning. and news items. marked Region 15- -I. Kyle, GIBAYZ ''G B2RS news - should reach RSGB HQ by first post that day (telephoned items can Region 16- M. S. Appleby, G3ZNU also be accepted until 10am). No guarantee can be given of inclusion in part or whole Region 17 -(Pos( vacant) of any item submitted and, once broadcast, items are not usually repeated. Region 18- W. Ricalton, G4ADU Region 19-R J. Broadbent. G3AAJ. SCHEDULE Region 20-G. Mather, G3GKA Time MHz Location and coverage (hf) or beam heading (vhf) of station 0930 3-65 G2MI, Bromley. Kent (SE England) 1000 3-65 G8ML. Cheltenham (SW England) HONORARY OFFICERS 144-50 G3FZL, London Awards managers 1015 3.65 GI3GAL, Belfast (N Ireland) hf-C. R. Emary. G5GH 1030 3.65 G2CVV. Derby (N Midlands) vhf -Jack Hum, G5UM 144.50 GM8FFX, Aberdeen INE Scotland) Emergency com munications manager 144-50 G3PWJ, Brierley Hill (NW) Balestrini. G3BPT 1045 144-50 G8LIC, Middlesbrough (NW) HF manager 144-50 G3F2L, London E. J. Allaway, G3FKM 144-50 G3SMT. Stockport (NN W) 1100 3.65 G5VO. Bridlington (NE England) Intruder Watch organizer 1115 3-65 G3LEQ. Knutsford (NW England) S. A. G. Cook, G5X8 144.50 GI3TLT, Bangor. Co Down (N) Microwave manager 1130 3.65 GM3TCW. Wishaw. Lanarkshire (S Scotland) D. S. Evans, G3RPE 1145 3-65 GM3HGA. Aberdeen (NE Scotland) Slow morse organizer M. A. C. MacBrayne. G3KGU Trophies manager An my news bulletin. callsign GB2ATG, is also transmitted every Sunday at 1200 and P. A. Miles. G3KDB 1900 on 3-590MHz and at 1230 and 1245 on 144.6MHz. This bulletin carries items of VHF manager: I F. White. G3SEK interest to rtty enthusiasts.

Correspondence to RRs and honorary officers should be addressed directly to them (OTHR). RSGB QSL BUREAU E. G. Allen, G3DRN, Tape/film library 30 Bodnant Gardens, London SW20 QUO Contact membership services officer at RSGB HQ

RADIO COM MUNICATION May 1979 407 Current comment band is also proposed, with a degree of sharing between broadcasting and mobile services, again to provide flexibility for the future. In the ultra high and super high frequency ranges the UK proposes W ARC 79—UK proposals numerous changes to cope mainly with foreseen increases in the requirements of various satellite services, while in the highest ranges— The following statement has been issued by the Home Office: above about 40GHz — the UK proposes a virtual replanning of the radio frequency allocations to provide a flexible foundation for future exploita- The United Kingdom proposals for the 1979 World Administrative Radio tion of the bands by diverse groups of space and terrestrial services. Conference to be held in Geneva (24 September-30 November 1979) In the related fields of international frequency management pro- were published on 10 April 1979. cedures, the UK proposals reflect concern to protect all countries' The proposals are in two parts, with each main section having its own equality of rights to use the radio frequency spectrum and the geosta- introductory text. The first part of the proposals, comprising more than tionary satellite orbit, to moderate the effects of the first-come f irst- 300 pages, consists largely of the detailed changes the United Kingdom served principle that has operated for many years, to provide a would wish to see made in the international Radio Regulations to cater mechanism for effecting the changeover from the present pattern of for developments over the next 20 years. This part also contains pro- high frequency allocations to that now proposed, and to improve the posals, under other items of the WARC agenda, such as provisions for international records of frequency assignments maintained by the ITU. communications from medical ships and aircraft, and a suggested pat- The UK proposals also take into account a wide range of tern of future radio conferences. The second part, comprising 40 pages, technological developments in transmitting and receiving equipment contains a set of supplementary proposals of a more technical nature since the last major conference held in 1959, as well as the enormous that take into account the results of a recent meeting of the International body of work done by the International Radio Consultative Committee Radio Consultative Committee. during the last 20 years in the field of radio propagation and frequency United Kingdom proposals for the international table of frequency sharing by different radio services. allocations follow fairly closely the outlines given in the report issued by In broad terms, the UK proposals seek to bring the Radio Regulations the Home Office in April last year. In the high frequency bands the UK is up to date and to cater for future frequency requirements as far as they proposing increased allocations for maritime communications, for can be foreseen. At the same time they recognize the need to preserve broadcasting services and for amateurs. These changes are made possi- the frequencies used by many of the millions of radio sets and installa- ble by the transfer of very many of the world's international communications around the world which could not be modified without prohibitive tions onto satellites. costs. In the very high frequency range the proposals seek to inject a new The United Kingdom proposals are the product of a four-year pro- degree of flexibility into the international frequency allocations to cater gramme of work that has embraced all national usages of radio frequen- for the situation when the black and white tv transmissions have been cies, and takes account of the ideas gained from the Home Secretary's phased out, while an upward extension of the fm sound broadcasting exercise in public consultation conducted during 1977.

More mail delays Members may already know, from Post Office statements QT( published in the national press, that because of industrial action by Post Office sorters in London, all rebate and bulk second class postings into London were suspended from about amateur radio news 25 March. This affected the mailing of the April issue of Radio Com- munication from Norwich, with the result that serious delays in Zone E Council member delivery occurred in an area covering southern England, the Following non-receipt of any nomination for a Zone E Council West and the Home Counties. However, the Midlands, North member at last year's Council election, Mr D. H. Adams, Wales, the North, Scotland and Northern Ireland were not G W3VBP, again offered his services as a co-opted member. At affected, as mail for those areas does not go through London its meeting on I February, Council unanimously agreed to co- from Norwich, and the journal was posted to those areas on 5 opt Mr Adams to serve as Council member for Zone E during April. 1979. In addition to delivery of the journal, this dispute also disrupted other postal services in the London area, resulting in non-receipt of some copy from contributors in time to meet the Region 4 representation deadline for this issue of Radio Communication, including, un- The result of the ballot for a Region 4 representative was: fortunately, SWL news.

N. J. H. Grassby, G4CPY 66 votes M. Shardlow, G3SZJ 59 votes Licence figures R. L. Senter, G4BFY 8 votes The Honte Office recently supplied the Society with the follow- There were nine invalid votes. ing total UK licence figures: Mr N. J. H. Grassby was therefore elected Region 4 representative. 1954 — 7,708 1963 — 12,049 1971 — 20,489 1955 — 7,702 1964 — 13,067 1972 — 22,076 1956 — 7,925 1965 — 13,987 1973 — 23,756 1957 — 8,234 1966 — 14,934 1974 — 25,499 1958 — 9,116 1967 — 15,933 1975 — 27,750 QSL Bureau 1959 — 9,539 19E8 — 17,338 1976 — 29,052 The RSGB QSL Bureau will be closed from 4 to 25 June in- 1960 — 10,006 1969 — 18,281 1977 — 23,237 1961 — 10,504 1970 — 19,351 1978 — 24,711 clusive. Members are asked not to send QSL cards to the 1962 — 11,289 bureau during this period. The figures are at 31 December each year. The present licence, G8TAA -G8TZZ: Mr K. Draycott, G3UQT, 175 Oliver Road, which combined fixed and mobile licences into one licence, was Kirk Hallan, Ilkeston, Derbyshire DE7 4JW, has been ap- introduced in 1977. The 1976 figure included 4,636 mobile pointed sub-manager for this series. licences.

408 RADIO COMMUNICATION May 1979 "A Rugby, MSF, time-code clock" JUST PUBLISHED The author of this article, published in the February issue of Radio Communication, has advised the following additions and amendments: Radio Amateurs' Examination Manual Fig 3, C19. The note, omitted from the text, is: In the proto- 8th edition type clock, which used buffered ("B") series cmos throughout, there was found to be a problem with the monostable circuits by G. L. Benbo w, G3HB driving the shift registers, and C19 was fitted to effect a cure. However, it is probable that if "A" or "UB" series devices can The standard work for all would-be licensed radio amateurs be used for 1C2 and IC4, this component may not be necessary. studying for the Radio Amateurs Examination. This edition has Fig 8. Two components arc labelled C16; that adjacent to C18 been completely revised in order to take account of the recent changes in the examination format and syllabus. is, in fact, R16. Details of LI are 8in by +in dia ferrite rod, with about 370 turns A valuable feature is the provision of two sample examination papers, each containing 95 multiple-choice questions—answers of 34swg wire. The original coil had this in four layers, length are given separately. of winding 1 in. The inductance should be about 13mH.

Chapter titles are: Becoming a radio amateur; Electrical theory Regarding the MSF transmission, this closes down for and calculations; Semiconductors; Radio receivers; Trans- maintenance on about one morning per month; the time sent is mitters; Power supplies; Propagation and antennas; Transmitter bst or gmt, as appropriate for the time of year. interference; Measurements; Licence conditions; Operating practices and procedures; Tackling the Radio Amateurs' Examination; plus four appendices. Lost or stolen 120 pages, paperback £2.16 incl p p Lost or stolen in transit by Securicor in November 1978 from Harrogate to Southampton: Yaesu frequency counter YC601B serial 8F010459. Any information to G3DBU, QTHR, who Obtainable from points out that the "small print" of the Securicor consignee RSGB Publications (Sales) form which he signed limited the compensation they offered to £50 for a piece of equipment worth £145.

Stolen from the BBC car park, Shinfield Street, White City, RSGB callsign lapel badges London. On 17 August 1978: IC240 serial 6700746, plus remote channel indicator. On 5 February 1979: home-made The Society is pleased to announce that another supplier of 144MHz; the other club callsign, G8LTR, being the only one engraved callsign lapel badges has been obtained, and that put using a 2N5642 and relay antenna change-over. Both from these are once again available. Delivery will normally be three car of G8FRH between 10am and 6pm. Information to to five weeks. Orders should be sent to RSGB HQ, as described Shepherds Bush police station, or G8FRFI, tel 01-743 8000 extn in the current price list on the inside back cover of this issue. 4766.

World Telecom munication Day Stolen on 3 February 1979, from a car in Langley Road, 17 May 1979 Slough: lcom IC22A, serial 3407023. Information to Mr A. J. Farce11, tel 0753 (75 from London) 74842, or to Slough Police, The theme of World Telecommunication Day this year is tel 0753 31282. "Telecommunications for all". It was chosen to highlight the fact that communication is indispensible to man's life, wherever he may be. The day marks the anniversary of the founding of the International Telecommunication Union on 17 May 1865. Microwave techniques for amateurs Can you help? This is the title of a symposium, held in association with the IERE, which will commence at The Radio Amateur Invalid & Bedfast Club is seeking representatives in the Merseyside, Manchester and West and 2pm, 5 June 1979 South Yorkshire areas to assist disabled members with equip- at ment and antenna problems. The club would also be pleased to The Royal Institution receive offers of good communication receivers and ancillary 21 Albermarle St, London W1 equipment for its members. Anyone who can help is asked to contact the RAIBC PROGRA M ME 2 pm: Introductory lecture by Dr Dain Evans, G3RPE secretary, Mrs F. Woolley, G3LWY, 9 Rannock Court, 2.30pm: "Simple techniques for optimizing receivers" Adelaide Road, Surbiton, Surrey KT6 4TE. by Dr Charles Suckling, G3VVDG 3.15pm: "High-gain Yagi antennas" by Michael Walters, G3JVL The RSGB requires the following bound volumes of 4.30pm: "10GHz narrow-band techniques for troposcatter" Experimental Wireless for its library: Vol 1 (published by Per- by Julian Dannaway, G3YGF cival Marshall), October 1923-October 1924; Vol 2, October 1924- December 1925. Full details from: The Professional Activities Secretariat, IERE, 99 Gower Street, London WC1; tel 01-3139 3071. Anyone who can assist is asked to communicate with RSGB HQ.

RADIO COM MUNICATION May 1979 409 Components list A frequency counter for a Rin See text Cl See text R1, 16 2.7k2 C2,7 10yF 6V R2, 38 2.2k0 03,9 220pF disc ceramic R3 1kSI preset 04.5.12, 144MHz transmitter R4,5.6.7 15,16 100nF 10,11,12 4700 Cs 10nF disc ceramic R8 3300 C8 100nF polyester R9 most C10 22pF disc by N. B. PRITCHARD, G8AYM* R13,21, C11 1nF disc ceramic 24-37 1kfl C13 33pF disc ceramic R39 22Mfi C14 60pF trimmer T HIS circuit was developed to be wired into a 144MHz R40, 42 100k0 Capacitor voltages are R41, 43 12k2 1 transmitter fitted with a vfo, in place of a tuning minimums All resistors 11A, dial. Two circuit boards were used, one for the prescaler and carbon film 5% one for the main counter. The prescaler consists of ecl and ttl TR1,5,6,7 BC108 devices to obtain the high frequency characteristics required, Cl MC10216L* TR2.3,4 BC158 C2 MC12012L' while the main counter is built entirely of cmos ics which gives C3 7490 01 BZY88C5V1 etc good tolerance on power supplies—typically from 9V to 04.5 MC14553B• 15V—and relatively low current consumption, 100mA at 12V, 06.7 MC 14543B ' X1 2.097152MHz ca tiAM53107Nt 20pF parallel most of which is supplied to the displays, which are leds. The C9,10 4027 circuit was designed around parts readily obtainable by the C11 4073 Display 2 off NSB3882t author and thus does not employ any state-of-the-art tech- 'Motorola. tNational. niques, or claim to be either the simplest or most cost-effective solution. The prescaler (Fig 1) consists of a broad-band amplifier constructed with an MCI0216L ecl ic, which is a triple-line- receiver, with each stage cascaded and some positive feedback The main counter is based on the use of two cascaded applied on the last stage to form a crude Schmitt-trigger. This MC14553B ics. This device is a three-digit counter with stage supplies ecl-compatible signals to the next ic with a multiplexed outputs, ie only one four-line bcd output for all typical sensitivity of 20mV rms at 150MHz. Reliable triggering three counters, plus digit select outputs. The block diagram for is adjusted by means of R3. the MCI45530 is shown in Fig 2, and Fig 3 shows the complete Frequency division is obtained first by IC2, which accepts ecl main counter. Each ic is equivalent to six ics in more common input levels and gives ttl output levels with a division ratio of 10 circuit arrangements, ie it contains three decade counters and in this circuit. This is followed by 1C3, a 7490 + 10 counter three quad latches. The outputs from the latches are fed into a which further divides by 10. IC3 is arranged in the + 5, + 2 multiplexer with its own scanning circuitry, thus giving very mode in order to give a symmetrical output waveform, which is economical wiring arrangements. This means only four binary more suitable for the main counter. The whole prescaler is outputs and three-digit select outputs. The scanning oscillator operated from + 5V and consumes by far the largest propor- frequency is controlled by an external capacitor. CII, and by tion of the total current, ie about 200mA. feeding an out-of-phase scan signal to the second MC14553B only one set of three-digit clriver transistors is required, with •I I Hillside, Slough, Berks SL I 2RN. corresponding digits from each ic driven in parallel. The

o+5V at 200mA Cl 1-C6 1C7 Input See text T 10 I /74 R13 R4 R6 1k TT L Ir a 470 470 a!„ ECL le. Output See text 12 14 11 116 14 'Cl r7-.8 MC10216L IC2 IC3 MC12012L 7490 10 RI 2.7k 1 C2 C3 13 15 4 lo T220p R8 R9 TTL 330 220 c J J R3 R2 1k R5 R7 R10 R11 R12 I.c, 470 470 470 470 470 T r 2.2k i0On C4 C5 100n 100n * Tantalum type capacitors used In prototypes

Fig 1. 150MHz *- 100 prescaler

410 RADIO COMMUNICATION May 1979 M C 14553B

Multiplexer /T. ° External timing capacitor

Quad latch Quad latch Quad latch 10 Strobe

Gate & I

Op 01 07 03 1 0 0 0 1 0 2 0 3 2 Pulse Clocko — Units C Hundreds shaper +10 +10

13 Master ?reset

Fig 2. Block diagram of MC145538 Gaàe

CIO 229

+12V 1

St;obe

R20 16 +12v 1M

R16 IC5 IC4 2-7k MC 145538 MC14553B

TR1 11 I BC108 R14 Input 10k Ireg CIF) in o c a

R 5 C9Er 10k 2209 T +12V

R19 R18 R17 C12 12k 12k 12k 100n +12V +12V 1C7 IC6 MC14543 8 MC145438 — C16 f1 100n

9.1 1 1 1 1 1 1 116 1 1 1 1 1 11 ..R24 to 30 ..1231 to 37 7x 1k 7x 1k TR3 TR2 TR4 BC158 BC158 BCI58 T12T11 6T7 T2 T8 T131 7- 7 221-1.- TBRC t8 121 IT16T7 T2 18 113 1 Digit Digit Digit a b c d e t g dp 1k a b c d e l g driver 2 driver 1 driver 3

NSB3882 N583882 R22 1.5k Com mon-anode display com mon-anode display R23 12k digit digit digit digit digit digit / e c A6 A5 A4 A3 A2 Al _ 6 10 16 10 14 13 BC158

Fig 3. Main counter circuit

RADIO CO M MUNICATION May 1979 411 DIGIT 4 3 2 driving the left-hand display unit during the time slot for digits NS 83882 t and 4. Variations on this will be described later. The segment current is determined by resistors R24-30 and R3 I-37 (and also R2I for the decimal point) and is, typically as shown, I ke/ for I2V supplies. Variations for brighter or dimmer displays or dif- fering supplies are permissible. The data sheet for the MC14543B should be consulted for high current requirements for the led display. 11 1 1 11 1 1 1 1 1 1 1 1 1 The input signal from the prescaler is presented to IC4 via 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 TRI which converts the incoming til level signals to swing the Pin No Pin No full power rail of the cmos ics. 1.... n/c 9 .... n/c The general timekeeping of the counter is controlled by the 2 Cathode, e 10.... Com mon anode, digit 2 timebase circuit (Fig 5). 1C8 comprises a cmos oscillator and 3 _.. Com mon anode, digit 4 11 .... Cathode, b prescaler. The oscillator frequency is determined by a quartz 4 „„ nIc 12.... Cathode. a 5 nic 13.... Cathode, 1 crystal resonant at 2.097152MHz and is adjusted precisely by 6.... Com mon anode, digit 3 14.... Com mon anode, digit 1 C14, R39, providing bias for the oscillator. Power is applied at 7 .... Cathode, d 15.... Cathode, dp pin 8 (a maximum of 6V) via R38 and a 5V zener diode Di. The 8 .... Cathode, g 16.... Cathode, c output frequency at pin I is 60Hz and this is applied to TR6 to Fig 4. Connections to NSB3Ei22 display produce a signal swinging the full power rail. This frequency is divided in total by 12 to produce a square-wave timebase gate signal (I:1 mark-space ratio) of 5Hz (thus a low operational MC14553B, as can be seen in Fig 2, contains a pulse shaping period of 100ms). The 12 function is performed by four l-K network on the clock input terminal complete with a disable flip-flops (ie two 4027 ics) connected to divide in the following terminal. This has usefully been employed in IC4 to perform sequence: + 2, 3, 2. By gating out suitable periods in this the signal gating function via the timebase waveform. Clock counter system during the "dead" time of the timebase signal, pulses at pin 12 are fed to the counters when the disable ter- pulses can be generated to operate the strobe and reset circuits minal pin II is in the low state. During the high state, strobe of the main counter. This function is performed by ICI I, a pulses and reset pulses are fed to pins 10 and 13 respectively of triple-three-input AND gate. TR7 inverts the strobe signal to both IC4 and IC5. produce the requisite negative-going pulse. Reference to Fig 2 The display system can employ any arrangement of will show that the reset signal is in fact a MASTER RESET, and common-anode display, but the prototype used a pair of during the reset period the complete operation of the NSB3882 four-digit displays manufactured by National MC14553B, including multiplexing, is reset to zero. Thus the Semiconductors, of which only three digits were used from whole display would be seen to reset at 5Hz (for the period of each display. The format and pin arrangements for this display the reset pulse) and thus produce a flickering effect on the arc shown in Fig 4, such a device yielding very simple wiring display. This is easily overcome by differentiating the reset requirements relative to hand-wiring six individual displays. pulse via C10, R20 to produce a very narrow and therefore The decimal point is driven by TR5 and indicates megahertz by imperceptible reset action.

+12V

1U111 x1.2.097152 MR

IC9a 1C10b -LC13 4027 IC 90 1C10a 4027 — 33p 4027 4027 1139 IC8 16 t =I M M5310714 22M V e V e to 15 5 T 1-11. J o J — J 13

11 14 3 bc 2 a —MK a:1 e R S VSS R S R S VSS 7 6 121 19 al 12 9 B 5Hz DI C15 1141 5.1V 100n 1140 12k 100k 30Hz Timebase 60Hz gate

1C1 (pm +1214 71/6 2 o 4073 1pIn 7 ond) 13C106 Reset Count period o 100 ms 13 +12V 12V Timebase R43 gate 0 12k 3 strobe 12V 4 Strobe o 71/7 2 BC108 12V Reset o

Fig 5. Timebase and control circuit

412 RADIO COMMUNICATION May 1979 Table 1. Sensitivity of prescaler be increased to 150MHz, or higher, and R3 adjusted to obtain optimum sensitivity to as high a frequency as possible. Recheck Frequency Input voltage Frequency Input voltage that lower frequencies are suitably sensitive with reference to (MHz) (rms) MHO Irma) 5 1.1mV 100 5.5rnV Table I. 10 1.1mV 125 7.5mV 25 1.6mV 145 15mV Variations and modifications 50 2.25mV 155 18mV 75 5.0mV While the circuit was originally designed for a specific purpose, it is very flexible for other requirements. For instance note the Voltages quoted are from generator of 5051 source impedance, assuming following figures given as data for the MC14553B: a 50S-2 termination. fifr, = o/c. Guaranteed frequency response at I2V = 2-0MHz Guaranteed frequency response at 15V = 2-5MHz Typical frequency response at I2V = 5-0MHz Construction and calibration Typical frequency response at 15V = 7-0MHz The counter was constructed on two printed circuit boards as Thus with suitable input amplifiers and shaping networks the shown in Figs 6 and 7, and quad-in-line sockets were used for main counter will give the above results. Similarly, by remov- all ics. The suggested order of construction should be: timebase ing IC3 and feeding 1C2 pin 7 directly to TRI, a maximum first, and check for correct control signals as in Fig 5; then the guaranteed frequency range of 20MHz at 12V and typically main counter, checking for an all-zeros display; and finally add 50MHz. The resolution for the basic counter is 10Hz, for 10 the input amplifier and prescaler. A suitable accurate signal prescaler it is 100Hz, and using the — 100 prescaler it is lk Hz. should be applied to the input circuit, preferably to completely In conjunction with these variations, it is possible to vary the fill all the digits, and C14 should be adjusted for a correct position of the decimal point. TR5 via R21 is connected to the displayed frequency. Amplitude should be initially of about decimal point connection in either the left or right display 50-100mV rms to ensure a reading. Then the frequency should block as appropriate, and TR5 is driven via R23 from the digit

4.8" x 3•8 3.8x 2-0"

.7 '%v, 9 0_,

¿ lo!] 0.2;q•coc, 84, 9 ioo coc`cA "ive-6Alej co 8

scle_U13`)_`S 4cs ec e

Fig 6. PCB copper patterns viewed e'i à \ lit Uri I from foil side

RADIO COMMUNICATION May 1979 413 Input o IC9 IC10 ed. R2 Cl o MAIN COUNTER and o TIMEBASE C2 C3 Cl C4 C13 I- 4-r- 1-4R4 eilHe T 4-1 =1-*R5 ei C14 O X1 4- 01-*R6 R39 T IR3 1:1R1 •-0 1-0 R11 De- .N. Gncl •- =-•R10 •-i =1-• • • • r- 4 101 t R41 IC8 • • • • R42 I R40 IC11 • • • 5-1 t 0-4 1-4R8 Link •c .-11". C5 *-1F•C6 C15 -- b• • • • • R16 I:1* &-1 re7 R38 é die • • • ut +-[1-•C7 TR6 ini I C2 / C100--• C9 T Rig IC5 I 11 R12 R20 IC4 •- 0-• • • • • • • • • .• • • • T R eb e• R13 • • • • Cs • • • • 1•• • • • • • I .c • e R15 • • • • 1 • T R7 • 2 R43 •--411

Cl %' C12er l C6 R11)11 • • • é • —• • • • • • • • • • • • • R19 I+5Vr • • • e• U ee 3 • • • • • • • • R22 • • • • •• TR3 IC3 • • • • *- 0-• • • • • C• CI • • • TR2 ri e• • • • • R17 • - -1 1 - -ie •b TR5 R24 to R30 R23fl Cl R31 to R37 11 [PRESCALER o rit] iY / l à 1 R21 [) 4' Ili Output 1 • • Fig 7. Component layout from top side: ill Display l, Display main counter and timebase, (above) o prescaler

* A 180k if required Link points 1 toi. 2 t02 and 3 to 3

drive line according to the digit position (I, 2 or 3) required. left-hand display block, and R23 is switched as necessary be- Typically, to indicate megahertz with right-hand decimal and tween Al, A2, A3 drive lines. all the above three modes, the decimal point is activated on the A high input impedance circuit is shown in Fig 8, which could be used mainly with lower frequency working, although it should work to 150MHz. Otherwise Rii, and Cl should be Schottky barrier diodes chosen according to the requirements. In the prototype, Rin 2 x MBD102 1M +5V was absent and Cl was a lOnF disc ceramic. Tantalum t l o capacitors were used in the electrolytic and 100nF positions in + 22p

ir,77 1M

330 1k +12V 1I o BF256A

Input 100n 33k

BF363 or similar Output o

68p 1k 470

Fig 8. Prescaler high impedance input circuit Fig 9. A possible power supply

414 RADIO COMMUNICATION May 1979 +5V ought to function satisfactorily with suitable peripheral cir- TT L output cuitry, and would possibly be cheaper. Fig 10 shows a possible Input circuit for using the cheaper MC12013L as a prescaler. It from R11 should be noted that the MCI2013L is capable of dividing in excess of 550MHz and that, if preceded by a suitable wideband uhf amplifier and followed by a 74S90, measurements at 432MHz would be possible provided the main counter will work to about 4.5MHz or higher. A circuit for a broadband amplifier is shown in Fig 11. Note that Figs 10 and 11 have not been constructed by the author and are provided only as "food-for-thought". The approximate cost of the ics, not including the MC12012L, is £15. The cost of this device and the displays has not been included since preferences may vary. The author can- Fig 10. Alternative prescaler not undertake to supply pc boards.

laput +5V 500MHz 509

Fig 11. 500MHz broadband amplifier

the amplifier part of the prcscaler, although these are not par- Acknowledgement is due to Robin Hewes, G3TDR, for ticularly necessary. The pcb for the prescaler could be made reading and correcting the manuscript and for constructing a double-sided, with possible advantage, with all earth connec- second model. tions simultaneously made to the top-side copper. If constructed on non-coppered Veroboard, every effort should be made to keep earth connections as short as possible. The transistor types used throughout are non-critical, and typical types are indicated. IC8 is manufactured by National Semiconduc- tors for use with digital clocks and, as with XI (20pF parallel resonant), should not be too difficult to obtain. For some basic uses employing only the main counter, a resistor of approximately 180kS2 from TRI base to + I2V may Mobile Logbook be added to give more sensitivity as a fairly crude input This new pocket-sized logbook includes space for date; amplifier (see Fig 7). times; geographical area of operation; band(s); and Power supply arrangements will vary according to the remarks. Alternate pages are blank to allow extra user application used, but reference to Fig 9 will indicate a suitable notes on individual contacts, and the logbook features a circuit. The +5V rail should be stabilized fairly well, but the tough wire binding which allows easy fold back. main counter power rail is uncritical and may vary from 9V to I5V. 64 pages; wirebound 148 by 106mm £1 incl p&p The printed circuit allows for a connection to the "D" output of ICI0b which has a frequency of 5Hz. This was made in order to have a reference frequency for use with a "huff-and- IARU QTH Locator of Europe puff" vfo stabilizer. As distances worked on 144MHz continue to grow, so While the 2-097152MHz crystal is specified as being 20pF has the need for a QTH locator map which covers the resonant, there is no reason why crystals made for 12pF to whole of Europe. Here it is! Ideal for use in conjunction 30pF should not be employed if they are more readily with the new RSGB 4-2-70 QTH Award. available. It may be necessary to change the value of CI3 in order to be able to adjust for correct frequency with other 610 by 555m m €1.15 incl p&p crystals. During the course of writing this article the author has had Obtainable from cause to note the recommended one-off price given by Motorola for the MC12012L, ie in excess of £20. It would seem RSGB Publications (Sales) that the 95H90 by Fairchild or the MCI2013L by Motorola

RADIO COMMUNICATION May 1979 415 Rl An inexpensive high-Z accurate transistor Output voltmeter R1+ R2

by R. E. BARBER, BSc, G3NEF/ZC4RE* Fig 1. Op-amp circuit applications, however, this limitation would not be significant and so the circuit is included as a very inexpensive and versatile C OME time ago the author was faced with the problem of high-Z voltmeter. The other problem found with this circuit L.7 how to measure a wide range of voltages with series was that it is necessary to zero set each time the range is impedances of megohms. The measurements had to be accurate changed; this is due to the relatively high input current of the to within 2-5 per cent, and furthermore they had to be U741; in practice, however, this problem was found to be repeatable with time. No commercial instrument capable of insignificant. meeting the required specification within the limited budget of Unfortunately the 10mV range was critical to the author, the project being available, it was decided to build an instru- and so the circuit shown in Fig 3 was evolved at an extra cost of ment to meet the following specification: £5. The circuit uses a fet input op-amp in place of the first Measuring range 10mV to 400V fsd. U741, and meets all of the design criteria after calibration. In Input impedance Better than 15MS2 on all ranges. addition, Sib and R17 are no longer required, leading to a Accuracy Better than 2-5 per cent on all ranges. simpler circuit. The current taken from the supply was also Power supply 2 x PP3 batteries, self-contained. somewhat reduced, as the LH0042C uses less than the U74I. Low drift with time and temperature. The input impedance on all ranges was found to be better than Capability by modification to measure rf, af and mains I8MS2; this was calculated and measured using an impedance voltages, rms and peak values. meter at IkHz. In addition, the accuracy after calibration was Small in size, easily portable. better than 2-5 per cent on all ranges and had a better stability Due to the requirements of low drift, high sensitivity and with time than Fig 2. A point to note is that the accuracy is small size, it was decided to use operational amplifiers as the primarily set by the accuracy of the resistors used. Hence the active part of the instrument. The very high loop gain in the cost of the instrument can be reduced if lower tolerance open loop configuration of these amplifiers (approx 80dB) resistors are used, cg five per cent resistors will give rise to approx- makes them ideal for gain control by negative feedback, as the imately an accuracy cf five per cent. Finally it was found that the gain can be very accurately set; in fact, as accurate as the problem of constantly resetting zero each time the range was resistor values RI, R2 and R3 in Fig 1, where the gain input to changed had reduced to insignificant proportions. 121 +R2. output is equal to R2 To obtain the required ranges, Construction 10mV to 400V, without resorting to extremely high values of The component layout is not critical, in fact both ics were input attenuator resistance, it was decided that two operational mounted close together on the final instrument, but on the pro- amplifiers should be used in series, with the gain of the second totype they were well spaced with no noticeable difference in amplifier variable. operation. Care should be taken in soldering, and to use as The initial circuit design is shown in Fig 2, and with the com- short a lead as possible on all components, especially on the ponent values indicated it was found that the instrument met input attenuator as noise generated here will be very noticeable. all the specifications except one; on the 10m\' range only, it The author finally used small gauge Veroboard as the circuit was found that the imput impedance was 2-5M2. For most base and soldered the ics directly to this board, which in turn

Op amp 1 ()pampa 5854741 p.n11. Vcc +9V 58 54741 3. ..1 ›.41O pm 8 . V -9V R14 _L t 88 cl See 40 r R17 3.9k S o —\ !o 250k Sect 10mV 5 R13 o Fig 2. Prototype circuit of voltmeter

R1 812 IC2 tSee.et e 1000 18 x imn 99 R7 5.1k

R2 52a See Sect S1a +4 Re R15 R3 9000 4.3k RV3 180k T-T -T10k

84 R16 119k 4..7k Cl C2 Vcc 0.01 imA I SO 'Officers' Mess RAF Akrotiri BFPO 57

416 RADIO COM MUNICATION May 1979 Op amp 1 me 7. Vcc 4,3V OP arrœ 2 melt Vcc+9v LH0042C pm 4 Vcc -RV SN54741 0in 6..vcc -gv Re 3.9k 52;\ 10 mV + 0

RI R12 le x 1M R RV2 t2Ok 100(2 R9 5.1k ICI t R2 6 52a See text

+4 R6 R15 R3 114 4.3k 180k 4 7e73 IT Y10k

R4 Rie Fig 3. Final circuit of voltmeter lek 4.7k C2 -vcc T O.131 ...IT 1.1 1mA ad

was fixed directly to the meter terminals. All other components op-amp, Sib is required to bias the first stage so that the offset were also fixed and soldered on to the board (care should be voltage fed back through the chip itself, due co the poor taken not to overheat the chips when soldering them or other transfer impedance of the U741, comes within the range of RV I components to the board). The input attenuator was also built set zero control. When using the fet op-amp LH0042C this on Veroboard of the same gauge. All resistors used were one biasing arrangement is not required; however, if the Fig 2 cir- per cent high tolerance and stability, except the variable ones cuit is used, then the additional contacts on Sib could be used which were 20 per cent, and connected as shown to minimize to set the zero on each range, thereby reducing further the need their variations with time. to set zero on each range by adjusting RV I. The author felt that this added complication on Fig 2 was not worthwhile, as Setting up the biasing needed to set zero accurately varies with the U74I used (the variation is quite considerable and the values of bias- Having built the instrument, carefully check all the wiring for ing resistors can only be found by trial and error). correctness. Also, switch the instrument to its 10mV range and set RV3 to its maximum value; this ensures that the meter can- Future developments not exceed fsd on switch-on. Switch on and connect a 20mV dc A design is in hand to build a constant current rectifier section signal to the input, set RV3 so that the meter reads fsd plus for this instrument, thus giving it a linear scale on ac voltages about two per cent. Remove the 20mV signal and short-circuit up to 400V peak. This rectifier board will be placed between the input: adjust RVI for zero on the meter. Connect a 10mV the meter and the amplifiers and thus will be easily switchable. de signal to the input and adjust RV2 for fsd on the meter. It is hoped that with suitable modifications the resultant instru- The calibration of the instrument's active parts is now comment will be capable of measuring voltages to within five per plete and it should hold to within one per cent on all cent over the frequency range dc to 100kHz. At the time of ranges, including the divide-by-four (S2). Using the U741 writing, problems are being experienced both with linearity at very low meter deflections and with accuracy above 50kHz. Components list To obtain the required calibration voltage of 10mV, the Fig 2 Fig 3 accuracy of the 20mV signal not being that critical, the author R1 18x 1M11 All as Fig 2 except: used a U2 cell and a potential divider network. The circuit and R2 1MS1 + 7504:51 + 51k11 in series R6 values used are shown in Fig 4, an Avo being used to first check R3 1801c11 R17 omitted R4 18k11 Si 5-way that the cell is up to scratch at I -5V. R5 2kfl 1-section R6 9COft wafer R7 IkS1 switch R8 3.9kS2 Op-amp 1 LH0042C 1.5k R9 5.11(11 Op-amp 2 SN54741 R10 2-4 0 in parallel with 1COS1 i5V R11 18012 in parallel with 22011 R12 10011 10mV to within 0.61. R13 2-4k11 in series with 10011 R14 9.1 k11 +75011 + 51ft all in series R15 4.3kft R16 4.7kS1 Fig 4. Potential divider network for calibration voltage R17 2501e1 RV1 10k31 variable RV2 20kS1 preset RV3 10k11 preset If one wishes to measure dc currents, this can be achieved by Op-amps 2 off SN54741 or equivalent measuring the voltage drop across a known resistor. By using Cl. 2 0.01pF 50V vvkg unity value resistors, ie 0- I. I. 10S2. an almost direct reading 1mA fsd 3in scale S1 5-way Isection wafer switch meter can be achieved: a I W 0-01i1 one per cent resistor could s2 DPDT switch be used to measure current drawn from IA fsd to 10A fsd. D

RADIO COMMUNICATION May 1979 417 A modification to the G3ZSS digital morse code generator

by K. J. MARLEY, G3E10/HB9ALV*

In the February 1974 issue of Radio Communication, an article In an effort to provide optimal operating comfort, the control by G3ZSS described a simple morse code generator. The cir- circuitry was modified and extended as shown in Figs 1 and 2. cuitry employed provided for the reading of a 128-bit diode In this circuit, compared with the G3ZSS version, two leds matrix, and the start/stop signal was generated by a key or are provided to indicate clearly the state of the circuit; further, push button which had to be depressed as long as the signal was the start key generates an enable or inhibit signal which is to be transmitted. dependent upon this state. Also, a reset signal is generated On the spur of a digital moment, the author set about when switching on the supply so that all flip-flops are positively reproducing the circuit and noted several shortcomings; the set to a defined state. Another feature is the extended matrix most important ones being: capability of 256 bits by using the SN74150 multiplexer. (This (a) when switching on, some spurious signals can appear at the possibility was mentioned in the G3ZSS article.) keyer output; For those readers who are interested in the circuit function, (b) the keyer enable signal, not being a digitally defined quan- the following description will be helpful. tity, bounces and causes erratic starts; As soon as the supply voltage is switched on, the Schmitt (c) at high transmission speeds, the chance of message over- trigger combination (IC lef) begins to generate clock pulses. At shoot is great if the operator's reaction is not quick; the same time a further Schmitt trigger combination (IClab) (d) the output of the multiplexer is 1 (high) when the circuit is with timing circuitry releases a "clear" pulse which is applied not enabled, which means the keying relay is continuously to the two flip-flops (1C2ab) ensuring that their outputs are energized. defined (Q = 0 and i7) = 1). The led STOP indicates this state. As soon as the start key is depressed for a short period. Schmitt triggers 'Cie and ICId with timing circuitry, release an sEulenweg 7, Baden. Switzerland enable pulse which flips IC2a output i5 to 0 (low) and indirectly

0 to 500 7Speed - -4

IC1e IC1f

°C lock o Enable IC2a IC2b +5V

9 D o •,"*Run Key 2.2k IC1c ICld IC3b 100 6 9 6 IC3a Ck 3 Ck Cr Cr 47 2.7k 113

+5V 13 Cr +5V Run Stop

— 1- _.<12 End 2.2k ICI& IC1b 1 2 3 4

IC4

T150 2.7k

I 0 —ve

0+5V 114 114 114 114

ICI IC2 IC3 IC4 SN7414 SN7474 SN7400 SN74107

7 O ve

Fig 1. Basic control circuitry

418 RADIO COMMUNICATION May 1979 oEnable

IC5 IC6

12 11 9 8 12 11 9 a o End 23 20 22 21 d 1113 o Run 0.002 IC7 II Tone 470 1 11 13 —.17 4.7k 12 —.16 IC9 a1-1 2.0 1 3 IC9b 15 4 6 1 8 1N914 11 o +5V

14 I I 8 1 13 1N914 Matrix I CS RLA RLA1 Kr 9 23 I C9c I C9d 13 11 10 8 1k TRI BC107 12

o ve

o+5V 124 124 114 5 IS

IC7 IC8 IC9 IC5 IC6 1 5N74154 SN74150 SN74132 SN 7493 SN7493

— 173— 110 1. Ile

Fig 2. Counter, decoder, matrix multiplexer and output

IC2b output Q" also to 0 by reason of the state of the inter- will ensure that the memory-generated CQ and QS0 that mediate NAND gates IC3a and IC3b. In this condition the led (hopefully) follows will be transmitted at the same speed. RUN illuminates and the enable line to IC5 and IC6 is 0 so that Apart from the ics, all of which are easily obtainable, no the clock signal applied to pin 14 of IC5 can now be counted. special or close tolerance components are required, and the pcb The output signal appearing at pin 10 of IC8 can only be passed build-up is relatively simple. RLA1 was chosen from the range to TRI via IC9d when the second input of IC9c is also 1. This of reed relays in the standard 14-pin dil housing. As an added condition is fulfilled by the Q output of IC2b (RUN). safety precaution, sockets were used for all the ics. The tone generator, comprising two Schmitt trigger stages IC9ab, is also controlled by the signal appearing at pin 5 of IC9b and releases signal bursts to the output in unison with the keying impulses. Amateur Radio Techniques At the end of each 256-bit count, the negative flank of the 16th edn) pulse from pin 11 of IC6 is applied to the clock pin 12 of a JK Pat Hawker, G3VA flip-flop IC4 whose output Q thus changes alternately between Basically an ideas and source book, this ever-popular work brings 0 and 1 as each cycle is completed. However, since 1C3a will not together a large selection of novel circuits and devices, together change its output state unless both inputs are 1, the periodic with many fault-finding and constructional hints. changes of IC4 will have no effect. At any time during a count Chapter titles: Semiconductors; Components and construction; Receiver topics; Oscillator topics; Transmitter topics; Audio and cycle, a further pulse from the key via IC lc and IC Id will flop modulation; Power supplies; Aerial topics; Fault-finding and test IC2a to 1 and reset IC4 so that a 0 is applied to pin 2 of IC3c units; Appendix during the remaining period of the count cycle. With the "An alternative title for this book would be The Experimenter's Handbook. It is one of the finest collections of circuits, building change then caused by the next pulse to pin 12 of IC4, the NAND blocks, and design ideas, and is invaluable for the inveterate combination IC3ab causes IC2b to flop and pin 8 again amateur experimenter and constructor - -Amateur Radio becomes I. With the enable line high, the counters IC5 and IC6 (Wireless Institute of Australia). stop, shutting down the further count. 336 pages: paperback 0.95 incl p&p The circuit has been built-up on two separate pcbs corresponding to Figs 1 and 2. For those readers who employ an elec- Obtainable from tronic keyer, the possibility exists of extracting the clock signal RSGB Publication (Sales) from there and feeding it into the morse code generator. This

RADIO COMMUNICATION May 1979 419 Secure corners with The "miracle sky hook" Sellotape and insulation tape

by A. D. TAYLOR, G8PG*

support that will raise one end of an antenna to A between 70 and 110ft, that can be erected by one man in a couple of minutes, and that only costs a few pence, sounds like a pipe dream. Actually such a support is easy to make. It takes the form of our old friend the kite. Originally used by Marconi for his first reception of transatlantic radio signals, the kite. supported antenna seems to be largely overlooked by the present generation of hf band operators. This is a pity, as modern Cane side materials make kites very easy to construct, and give better per- 12" formance than some of the heavier materials previously used. This can be said with some confidence—a few months ago Tall attached here G8PG had never built or seriously flown a kite, but now his home-made models fly extremely well. If a kite is to support an antenna successfully it must be very stable in flight, thus allowing long periods of "hands off" flying, and it must have a good lifting capability. After various experiments, a design which meets these requirements has been evolved. It is simple and inexpensive to make. approx 18" Construction The kite used is a square kite, flown with two corners in the vertical plane and two in the horizontal plane (Fig 1). It is made from part of one of the polythene bags used to collect the waste in a kitchen pedal bin, four of the so-called "18in garden canes" obtainable from multiple stores, and a small fishing 24" hook swivel (the sw;vel isolates the kite from the twisting motion of the nylon kite line). Sellotape, plastic insulating tape and string will also be required during construction» One pedal bin liner bag should provide enough material to make two kites. Bridle side The method of construction is as follows. Lay two of the garden canes side by side and adjust the overlap until the total length is 24in. Using Sellotape, bind the two canes tightly together along the whole length of the overlap. Repeat the pro- approx 20ft to to start of antenna cess, but now using the second pair of canes. Carefully measure •. out and mark the exact centre point of each pair of canes. Make a cut down one side of the pedal-bin bag, then care- Fig 1. Construction fully open up the bottom, which is closed by means of plastic adhesive. The result will be a large sheet of plastic. Lay one pair of canes on the centre line of this sheet, with one end level the two pairs of canes cross until balance is achieved, then lash with the bottom. Secure each end of the canes firmly in place the two pairs of canes together at this point with thin string. by means of a piece of Sellotape. Lay the second pair of canes To make the bridle, measure a point 3in above one pair of over the first and exactly at right-angles to them, and carefully canes and 3in to the left of the second pair of canes. Fix a 1 in align the previously marked centre points. Fix the ends of the length of insulating tape to each side of the plastic at this point. second pair of canes firmly in place with Sellotape. With a pair Make a small hole through the insulating tape and plastic at the of scissors, accurately cut away all excess plastic until the point where the 3in guidelines cross. Do the same thing again, square shape shown in Figure 1 is obtained. Put more Sellotape but this time at a point 3in to the right of the second pair of over the four ends of the canes until they are firmly fixed to the canes. Pass one end of a length of thin string through one of plastic material, then further strengthen the joints with a piece the holes, tie it to a pair of spent matchsticks, then pull the of plastic insulating tape. Note that the kite is not collap- matchsticks up to the surface of the kite and fix them in posi- sible—it is permanently assembled and is transported by laying tion with insulating tape. Slip the fishing swivel over the free it on top of the luggage in the boot of a car. end of the string, pass the free end through the second hole in Balance the centre point, where the two pairs of cane cross, the kite, and adjust the length of the string to produce a V with on a finger. If the kite is not balanced move the point at which its apex 4in from the surface of the kite. Position the swivel at the apex of the V and secure it in place by putting a couple of 37 Pickerill Road, Greasby, Merseyside L49 3ND. turns of copper wire around the string. Secure the free end of

420 RADIO COMMUNICATION May 1979 the string by means of matchsticks and insulating tape as already described. The kite is then complete. Assembly only LI takes a few minutes and the cost of materials is about 6p.

The line/antenna To transmitter The 150ft line used with the kite is made from the so-called "stunt kite line" available from toy shops; this is a very light nylon line, usually sold in 100ft lengths. The small plastic winders supplied with these lines are not suitable for antenna work, so when the line/antenna has been made it should be wound onto a piece of board 8 by 6in with slots 1 in deep and Fig 2. Coupling circuit 4m wide cut in the narrower ends. As the weight-lifting capacity of a kite is limited, the antenna suggested consists of 130ft of 28swg enamelled copper wire, plus a short lead-in. Experience reaches a reasonable height, then move back to the winding by other operators using "invisible" antennas shows that this board and pay out the remainder of the line/antenna. gauge can handle up to 150W. If the kite is stable but rises sluggishly and [hen stops rising, To make up the antenna, reel off 135ft of kite line and fix it take weight off the tail. If the kite takes up a position horizontal firmly between two supports, such as spades, driven into the to the ground and then falls, try additional weight on the tail, ground. Clean I in or so at one end of a reel of 28swg wire and and if this does not give a complete cure slightly shorten the solder 4ft of light, flexible, insulated wire to it. Attach the joint bridle by moving the position of the wire binding. if the kite firmly to the kite line, 4ft from one end, by tying it on with thin rises well but side-slips violently to earth, slightly adjust the string and then taping it in place. Keeping both kite line and position of the point at which the two sets of canes cross (by wire under tension, reel off a further lOft of wire and tie to the moving the lashing in the horizontal plane) until the instability line at the end of the 10ft section, using thin string. Repeat this is cured. Time spent in careful adjustment is repaid by the abili- every 10ft until 130ft of wire has been reeled out. Cut the wire ty of the kite to fly "hands off" for two or three hours at a and secure the end of the last 10ft section to the line by twisting time. Once the antenna has been paid out, the bottom of the the last 2in round the line and taping them in place. The line/antenna should be secured to a suitable anchor at the point line/antenna is then wound on to the winding board, starting at where the lead-in is attached. A small garden fork driven into the lead-in end. the ground makes an excellent anchor. In tests so far made, this antenna has been worked against a counterpoise consisting of the chassis of a saloon car. Coupling Test results to the transmitter has been with the aid of the coupler shown in Tests carried out from GW8PG/P used a 3W transistor cw Fig 2. Components LI, Cl are chosen to resonate at the desired transmitter to excite the antenna on the 14, 7 and 3 .5MHz operating frequency, tap TI is adjusted to provide a good bands. Despite poor summer daylight conditions, excellent match to the transmitter output, and tap T2 is adjusted to pro- results were obtained. One 30min session on I4MHz produced vide maximum rf into the antenna. contacts with seven European countries in an arc from Sweden One point is worth stressing. Even in breezy weather the to Spain, indicating that, even though there is some slope on wind does occasionally die away for a minute or so, and this the antenna, it is still largely omni-directional. On 7MHz all of may allow the kite to sink gently to earth. lf QRO equipment is western Europe was worked, and on 3.5MHz a distance of 250 being used to excite the antenna this might cause a mismatch at miles was worked at mid-day. The advantages of a high [he transmitter output, so to avoid any possibility of damage it antenna and an absolutely quiet location were also very apparent is suggested that QRO equipment be run at not more than 75 when receiving; QRP (3 to 9W) stations in seven European per cent of its rated power when attached to a kite antenna. No countries being both heard and contacted. Indeed it is not until problems have arisen when using QRP all-transistor equip- one goes to a really quiet location that one can appreciate the ment. unbelievable level of electronic environmental pollution that exists in most urban areas. Flying the kite Before attempting to fly a kite, the following safety precautions should be noted: (1) Never fly a kite where it can fall on power lines, telephone lines, roads, people or animals. TECHNICAL ARTICLES (2) Never fly a kite if there is a possibility of lightning in the area. Technical articles on subjects of amateur interest are always (3) Never fly a kite above 200ft (unless special permission has welcome and should be submitted to: The Editor, Radio Communication, 88 Broomfield Road, Chelmsford, Essex been obtained). CM 1 18S. To prepare the kite for flying, tie the end of the line to the All articles received are reviewed for technical merit by the free ring on the swivel, and tie on the tail at the point indicated RSGB Technical Er Publications Committee, or an acknow- in Fig I. If the wind is strong, tie one or more additional pieces ledged expert on the subject, before acceptance, Payment will of cloth on to the tail. Lay the kite flat on the ground, reel off be made for all articles published. about 60ft of line/antenna, and weigh down the winding board The editor will be pleased to send intending authors a copy of with a heavy stone. Return to the kite, stand back to wind, hold the RSGB Style Guide and to give any other advice and the line loosely in one hand, and launch the kite with the other assistance requested. hand. Move back quickly, paying out line until the antenna

RADIO COMMUNICATION May 1979 421 Monitoring. Miniature light-emitting-diodes can form the basis • of systems for instant visual monitoring of a wide variety of technical "fault" or "regular" conditions by means of "green", "red" and "flashing" displays (five-state led displays can be devised using dual red/green led units combined with a 555 timer, see topics later). Some monitoring suggestions made by K. lesson include "green" to show whether a power supply is regulating, or "red" to indicate it is in current limit; locked or unlocked Pot Hawker, G3VA phase-locked loops in synthesizers; an indication whether a circuit is sampling properly, etc. Low-current leds and torch bulbs cost less than miniature meters but give an immediate indication that a system is "go" or "no-go".

Crystals and crystal oscillators recent TT noted that the advice "keep it working" A becomes increasingly more difficult as equipment Many amateurs still look upon a crystal-controlled oscillator as becomes more complex—and also, paradoxically, as com- a high-stability system, regardless of such factors as ponents become more reliable. In the old days a high percen- capacitance loading, drive levels, ageing, and the differences tage of all faults could be traced and cleared by the straight- between parallel, series and overtone modes, etc. It is often not forward process of "valve pulling" (although, in fairness, one recognized that ideas on frequency stability have changed over should admit that in practice a significant percentage of all the years to the stage where plugging any crystal into any valves achieve incredibly long working lives). While "keep it oscillator circuit cannot be expected automatically to provide simple" is one way of making it easy to find and repair faults, the sort of stability and performance demanded today. It has one cannot shut one's eyes to the fact that some of the equip- often been pointed out that not every channelized vhf ment now found in many shacks represents complex systems, transceiver comes up truly on channel or stays truly on chan- even if much of the complexity is absorbed into the world of nel. And although modern crystal units are more reliable and microelectronics. More and more of the equipment less subject to contamination from dirt than the old war- breakdowns can be traced to what are basically mechanical surplus units, nevertheless the size of the crystal plate is faults, particularly those stemming from the thin, fragile wires generally very much smaller, calling for extra care in drive and less-than-perfect printed boards, or damaged connectors levels. Again, stability of crystals, like good wine, improves and switch contacts. Good mechanical design does not always with age, while the highest order of frequency stability tends to go hand-in-glove with the ingenious electronics of modern come from crystals with fundamentals in the range 4-5M Hz. equipment. A useful survey article "Quartz crystals—gems for frequency control" by Don Nelson, WB2EGZ, appears in Hain Radio Keep it serviceable February 1979, pp37-44. This includes a considerable number of oscillator circuits, mostly of familar form. Several of the So what can the amateur designer and constructor do to improve the "serviceability" of his equipment and so reduce the overtone oscillators, however, may be new to some readers and examples are shown in Figs 1-3. "mean time to repair" (mur)? Some useful ideas have been put The following general advice is also based on WB2EGZ's forward by Kenneth _lesson in an article "Product service- article: ability" in Electronic Design (No 8,12 April 1978), and a selection of these and other suggestions are presented below: When ordering a crystal for a given frequency, you must specify series resonance or parallel resonance at a specified Physical construction. How long will it take to reach and load capacitance. It is recommended that operation should be remove a faulty component in various parts of the equipment? in the positive-reactance mode when above series resonance, There used to be one, now long-obsolete. British television receiver which it was said involved removing over 50 screws and much desoldering to reach some of the vulnerable stages. Today much equipment is built on a single large pcb, as this is the least expensive form of construction for a manufacturer. But for better serviceability it may be preferable to use a number of smaller boards fitting into a mother-board using edge connectors; this may allow faults to be more readily isolated, traced and repaired. The modular concept, with small boards, also tends to make component replacement easier and less time-consuming, as well as facilitating field replacement using spare modules. Labelling. Labelling and indicating components so that they can be identified from circuit diagrams also results in better serviceability. Where boards could require servicing on both sides, component identification should be provided on both sides. It is useful to be able to identify readily which is pin I on an ic, or which is the negative side of a capacitor, or the emitter Fig 1. A typical Butler overtone oscillator (20-100MHz). The se- of a transistor: a tip here is to use a "square pad" connection cond stage should always be a foal, as the circuit is not reliable point to distinguish this pin or lead from the circular pads used with two bipolar devices (two fets may be used). Overtone fre- for the other connections. It adds nothing to the cost. quency determined by LC values

422 RADIO COMMUNICATION May 1979 jumping frequency into a spurious mode. Excessive heating may cause a permanent shift in frequency (NT-cut crystals are C2 particularly vulnerable to fracturing). Generally, use lowest 4-40 possible drive levels compatible with good starting 2144124 4-1 ' characteristics. 1k Pressure-type crystals may become inactive due to particles from the rubber gasket, but careful cleaning with alcohol or

„, 330 similar solvent will bring them back to life. This cannot be T- done with solder-seal holders, which should not be opened (or Cl h will result in a frequency shift due to change in pressure). 7r- 4 -40 Natural quartz still has a higher Q than synthetic quartz, 45 MFR. stall Tap 2 although this has the advantage of perfect crystalline structure and uniform size.

II 0+12

Crystal Heart attacks and geomagnetic activity Switch 2.2k In TT recently (January 1979, p30) reference was made to the 2.2k strange but strong correlation that has been found between c—C=1 sunspot maxima and virulent flu epidemics. Other medical Fig 2. Overtone oscillator with crystal switching. The large induc- researchers appear to have found equally odd and inexplicable tive phase shift of Ll is compensated for by Cl. Since overtone links between solar activity and health matters. For example, crystals have very narrow "pulling" bandwidth, the trimmer has a Dr S. R. C. Malin and Dr B. J. Srivastava have reported, in smaller effect than with fundamental-mode operation Nature, an apparent link between the daily number of admis- and in the negative-reactance mode when below series sions to the cardiac thoracic wards of two hospitals in India and resonance. Oscillators using fundamental crystals usually geomagnetic data in the form of daily sums of Kp (the operate in the positive-reactance mode with a trimmer for exact planetary index of geomagnetic activity) normally used as a tuning. measure of the effect of solar particle flux. The data have sug- Crystals with frequencies higher than 20MHz are usually gested that admissions tend to increase with magnetic activity overtone types and it is generally practicable to excite AT- and to a much closer degree than could be explained by chance. BT-cut plates for 3rd, 5th, 7th and 9th harmonics (the overtone There seems no logical reason why the heart should be affected frequencies are approximately, but never exactly, equal to the by what are, after all, relatively weak changes in the magnetic harmonic frequencies). To use an overtone crystal most effec- field, and the researchers admit that there may be some other tively, a high-Q tuned circuit must be used to excite the crystal cause (of solar origin?) responsible for both the magnetic and in the desired harmonic mode, and no other resonances should medical phenomena. It all becomes curiouser and curiouser! be present that might excite the crystal to another mode. Over- tone crystals are designed for series resonance and are not suitable for direct fm or vxo systems; they can be used for Beam with multi -band element phase-lock operation. Such characteristics as temperature co- It is still not universally recognized that a plain and simple efficient and equivalent resistance apply only at the design dipole element (no traps) can be used effectively on, say, 14, 21 frequency and will differ for operation at the fundamental or and 28MHz provided that the transmission line is tuned and other harmonic orders. able to withstand a high swr without undue losses. The tech- Old pressure-type crystal units with larger pieces of quartz nique is to use a centre-fed element with the whole than their modern equivalents will withstand higher drive antenna/feeder system brought into resonance by means of a levels; changes in drive level affect the frequency, and crystals suitable antenna tuning unit. For example, some years ago Ed operated at high drive levels may become unstable, sometimes Tilton, W I HDQ, described a 33ft 2in "guy-wire doublet" for 14/21/28MHz using any convenient length of open-wire o .5 to 12 110C transmission line (ARTS/6). C3 In Amateur Radio February 1979, Steve Bushell, VK3BHQ, • Output sine wave uses this approach for a low-cost hî beam: Fig 4. This started off as a I4MHz monoband but he soon discovered the driven element could be used effectively on 21MHz (extended Zepp)

Driven element broken - Cl al centre and insulated P en boom

Open wire 3S-4-Driven element teed

9'10.

0 V

Fig 3. A 50-100MHz overtone oscillator using 2N918 bipolar tran- 23.-5* • 15m Reflector sistor and AT-cut overtone crystal. L1-C2 tune to required frequency. 12 is arranged to resonate at oscillator frequency in con- 35-- 0« - 20.1 Reflecto. junction with crystal shunt capacitance (about 6pF) to tune out effect of this capacitance. At 90MHz 12 is about 0'5H. C3 is Fig 4. VK381-10's multi-band Yagi antenna using open-wire varied to match output feeders to allow use of 33ft driven element on 14, 21 and 29MHz

RADIO COMMUNICATION May 1979 423 ANTENNA capacitor limits the noise eenerated and so reduces the accuracy of the instrument. After the value had been reduced it was found that the unit provided a "steadier" reading, with less "drift" of the meter. The logarithmic amplifier can be improved by using a CA3130 device which has greater bandwidth than 450pF 450pF the 741. I MP (2) A crystal filter in a receiver acts as a "delay line" to the signal and, when dealing with any receiver having a crystal 10 turns 2" Dia. filter, it is preferable for the chopping signal to be delayed by a corresponding time. This delay time will vary from receiver to 4 turns 2" Dia. receiver, but an average time delay for an ssb filter is about I ms; cw filters have greater delay times. Fig 6 shows the circuit 450pF diagram of a simple means of adding a delay circuit to the multivibrator; the discrete transistors correspond to those used Î ft li in the original unit. LA8AK considers that the easiest way to i I I I adjust such an oscillator without using either trimmer- Coax input capacitors or potentiometers is to use parallel connections of resistors and capacitors, as indicated. When Cl and RI are Fig 5. Antenna tuning unit to provide balanced output to the open-wire feeders of the VK3131-10 array. Taps are adjusted to pro- chosen to provide the correct time constant, the frequency may vide correct matching and should be an equal number of turns be tuned up or down by adding resistors (R2) or capacitors from the centre of the inductor (C2). The actual frequency for this application is not critical, so no final adjustments should be necessary. and 28MHz (two A/2 in phase). He added a A/2 reflector for LA8AK mentions that he uses only a single power supply line 21MHz but considers that even without a further 28MHz ele- from a standard 12V psu, the negative voltage being supplied ment the system also provides good forward gain on that band. from a cmos inverter using an MC14049BCP device and a two- Total cost was around $A45. One form of suitable atu is shown diode rectifier/voltage doubler arrangement. He also reports in Fig 5. that LA6MQ is developing a new version of this useful alignment aid, following rather different principles and requiring Alignment aid improvements only a single supply voltage. In Radio Communication January 1976, J. R. Compton, G4COM, described in detail "An alignment aid for vhf Hypodermic needles—a warning receivers" which enabled vhf receivers to be readily adjusted In reporting the use of a stainless steel hypodermic needle as an for maximum signal-to-noise ratio, rather than just for max- effective ic desoldering device (TT January 1979, p32) G4DYF imum gain. It provides a continuous read-out of the difference confessed to obtaining a couple of used needles, although he between the audio output of a receiver with no rf input, and the pointed out that the size required is not normally used for mak- output when a wideband noise generator is connected to the ing injections but for loading the syringe. antenna socket of the receiver. This unit has gained wide Richard Francis, SRN, G4E1E, stresses that although it is respect as a genuinely useful item of test gear, and follow-up possible to obtain such needles by devious means, needles items on alternative noise sources were contributed by LA8AK which have previously been used by medical or nursing staff (TT February 1978, pp133-134) and ZL2APC (TT June 1978, can be very dangerous. He writes: p511). "The possibility of contracting hepatitis from a con- Now Jan Martin Noeding, LA8AK, has come up with some taminated needle cannot be over-emphasized. Hepatitis is a modifications which he considers extends the usefulness of the condition which can be fatal and, although precautions are unit still further. He writes: taken to prevent contaminated needles being lost, they can (I) Experience indicates that the original value of capacitor sometimes get through the isolation arca. Although the CI is too large; it is preferable either to substitute a lOnF desoldering technique is a splendid one—not with hypodermic capacitor or to remove the component altogether. This needles which have been used."

Noise generator Chopper Fig 8. LASAK's modification to cct. the G4COM alignment aid provides a delay circuit to the chopping muttivibrator

— r 1 —.1- 1 — (Noise function)

(Chopper function) —4 4-1 ms delay

424 RADIO COM MUNICATION May 1979 Dual-polarity and high-current supplies 555 A. Bayliss in Electronics Australia (December 1978) provides a simple solution to the problem of obtaining a dual-polarity supply (positive and negative rails with respect to OV) for solid- state devices when using mains transformers not having a centre-tap on the secondary winding: Fig 7. This uses a form of voltage-doubler arrangement, creating a centre tap for the dc output and then using two similar zener diodes to regulate the supply so that it is balanced about OV. Component values and ratings need to be chosen to suit the output voltage and load.

9 -15 V Fig 7. Dual-polarity low-voltage supply without centre-tapped transformer winding Fig 8. Five-state led monitor, with steady or flashing green/red display. While developed for a paging system, it could be adapted to amateur equipment A rather different psu requirement is beginning to make itself felt: the very high currents now demanded by the pack- aged solid-state power amplifiers rated at up to around 100W vhf The original system works as follows. An external signal trig- output. For, while plenty of low-cost designs capable of pro- gering relay, A, controls the colour of the led, changing it from viding up to around 4-5A have been published, one now needs green (idle) condition to red. Relay B puts the 555 timer in the some I5-20A. There are some ex-computer units knocking astable mode, changing the dc state of the led to an on-off about; but another solution (suggested by Robin Hewes, G3TDR) oscillation of about 7.5Hz at a duty cycle of about 50 per cent. is to use, even for fixed operation, a spare large-capacity car The frequency can be adjusted by selection of RI and Cl. To battery plus trickle charger. It is perhaps not an elegant solu- obtain the emergency red flashing mode, both relays must be tion, but well-regulated 20A supplies can be quite costly. Some tripped by external signals. Current drain (not including relays) readers may be tempted to suggest there is another solution, is about 40mA. called valves, but true solid-state enthusiasts would reject that as the coward's way out! CW over two -core cable Any other ideas for a low-budget high-current supply? Brian Castle, G4DYF, feels that there is still a role for line communication using morse code. Such a signalling system would be particularly useful to pairs of youngsters without a licence and wanting to gain practical experience of cw Five -state led display operating in readiness for the day when the signals can be laun- In Electronics 15 March 1979, D. F. Fleshren describes how he ched through the aether. Most of us still remember the uses a five-state led display to monitor a paging system. Fig 8 traumatic experience of finding that while the Post Office shows his system, which uses two relays and a 555 timer to send examiners are satisfied with just copying and sending, real-time, an appropriate signal to a dual red/green led unit (Monsanto two-way operating requires in addition fluency in procedure MV5491, Xciton XC5491 etc). signals, codes and abbreviations; such skills cannot be acquired Off (no power) indicates that paging has been cut off to that readily from even the most sophisticated random code station or the region in which it is located. generators, tapes or records. Steady green signifies that the station is operational, but not G4DYF considers that while circuits that provide two-way being paged. signalling are published occasionally, they almost always call Steady red is the individual station's paging signal. for more than two wires (or two wires plus earth) between the Flashing green tells the user that all stations in the system are stations if the sender is to be able to monitor his own sending. being alerted. Today, wire tends to more expensive than a few extra com- flashing red signals an emergency situation to all monitoring ponents, and it can prove cheaper to provide a tone-oscillator stations. and associated battery at both stations provided that only .a Clearly such a system could readily be adapted to meet the two-core linking cable is required. requirements of, say, a transceiver. It might also be possible to His unit makes use of two simple uni-junction transistor replace the relays by means of current steering diodes. relaxation oscillators (reported in TT June 1974 by Sven

RADIO COMMUNICATION May 1979 425 his debt to Brown's paper in his book Big Ear) and published the first of his many articles on 8.1K "flat-top" close-spaced Bi Q 82 arrays in Radio March 1937 (see also QST January 1938). E These were thus the first close-spaced flat-top rotary arrays 2N2160 but, although Brown's paper indicates how driven arrays can be made uni-directional, the basic 8.11( arrays were bi- directional. It was not until considerably later that such driven elements were implemented as uni-directional hf arrays in the form of the G8P0, ZL-Special, HB9CV and, most recently, the UA3IAR antennas. To piontocal CiiCul (4) The Roberts rotary I4MHz Yagi, as illustrated in Ti' (January 1979) and published originally in Radio January Fig 9. Two identical units provide two-way morse signalling over two-core interconnecting cable while allowing sender to monitor 1938, was inspired by the parasitically-excited rather than the his keying. Note that the device is a unipolar transistor driven array section of Brown's paper. It emerges firmly as the first, published, unidirectional beam of this type and is thus the Weber, G8ACC, from an idea by a Finnish listener), as shown progenitor of the vast majority of present-day amateur beams. It also emerges as the first beam to use the "plumber's delight" in Fig 9. No blocking capacitor is required because the uni- junction devices are non-conducting in the idle condition. For form of construction. privacy, cheap low-impedance earpieces can be substituted for While the work of both George Brown and John Kraus has rightfully long been recognized in both the professional and the loudspeakers. RI (selected to suit and usually about 151a2) amateur fields, the practical development by Walter Roberts of ensures that oscillation does not stop at any setting of the RV I frequency control. The volume is low, but adequate for per- the close-spaced flat-top Yagi (a development acknowledged briefly in QST October 1938 in a note "Principles outlined by sonal listening. Brown, simplified by Roberts") has been overlooked and The comment about privacy and personal listening reminds me of the day in September 1938, at the height of the Munich forgotten for 40 years! Roberts, incidentally, later published crisis, when I reported to my local Post Office for a morse test valuable papers in RCA Review on the development of the (yes, in those days most Post Offices still had staff with folded dipole and the stability of variable frequency oscillators experience as manual telegraphists, so there was no need to travel (acknowledged by E. O. Seiler, W8PK/W2EB, when he developed the "Seiler" oscillator). miles to take the test). To my chagrin the local postmaster (who was the examiner) produced a letter from one of my neighbours A couple more interesting sidelines. That part of Dr Brown's paper which inspired the development of the W8JK driven- claiming that I had been transmitting in morse for weeks. What he had heard was my practice sessions on an oscillator and array had previously (in 1932) been rejected by an IRE loudspeaker! "referee". George Brown and Jess Epstein themselves built a dual-band I4/28MHz array for an amateur colleague (exact date unknown) but were too busy to respond to requests from The close-spaced pioneers QST to describe it in print. During the war close-spaced arrays My suggestion (TT January 1979) that the first close-spaced were supplied to the military and resulted in the receipt of rotary Yagi antenna (and the original plumber's delight) may several protests from "Colonel Blimps" that the elements were have been the I4MHz array described by Walter Van Roberts too close together! Les Moxon, G6XN, has drawn attention to (then W3CHO now W2CHO/K4EA) in the January 1938 issue an ARRL Handbook vhf design with wide-spacing that of Radio, has brought in very interesting letters from the two survived in print at least as recently as the 1970s! surviving members of the "Roberts/Brown/Yagi" triumvirate. And Walter Roberts, now well over 80 years of age, ruefully It has also been possible to make a search through the 1937-8-9 recalls an earlier occasion of receiving "feedback" from volumes of QST although 1 have not yet located the correspon- England. In contact with a London amateur in the late 'thir- ding volumes of Radio. ties, he innocently asked him to phone his cousin and pass As a result of the extra information gleaned. I feel it is now along some trivial family message. This was done but, unfor- possible to put on record the following summary of events: tunately, his cousin was the then Postmaster General, who was (I) The wide-spaced Yagi antenna was well established in annoyed at becoming a party to a breach of his own rules about both professional and amateur circles by about the mid-'thir- amateur traffic handling. As Walter Roberts points out, any ties. G6FU, for instance, has drawn attention to designs and possible loss of revenue to the Post Office was more than made polar diagrams in The Radio Handbook, 1938 edition. good when the incident resulted in five transatlantic cables to However, such designs accepted without question the belief clear it all up! that reflectors should be spaced A/4 and directors 3A/8 (usually) from the driven element, making "fiat-top" construction very difficult. Zip or coaxial cable? (2) The wide-spaced concept was first exploded in the long A difference of opinion that may bring back memories to old- and very detailed paper by Dr George Brown of RCA in Proc timers has been aired recently in the columns of Ham Radio. In IRE January 1937. This paper, representing some years of the April 1978 issue, Evert Fruitman, W7RXV, wryly described intensive work, covered the design of both driven and his attempt to use cheap zip-cord cable (the modern equivalent parasitically-excited arrays in monopole form, and remains of electric flex as used on low-wattage domestic appliances) in now, as then, the definitive paper on this whole class of end- lieu of coaxial cable for feeding hf antennas. His advice, like fire arrays. Punch on marriage, can be summed up as "don't". He (3) Dr John Kraus, W8JK, very quickly recognized the vital reported power losses of some 60 per cent with 30-60ft of zip- importance to amateurs of the close spacing (he acknowledges cord, even on the 3.5MHz band.

426 RADIO COMMUNICATION May 1979 But in the February 1979 issue, Tony Garatt-Read, ex- C 1 Rl 8211 G3VBZ/Ve I, comes back with an account of his successful use 0 — of zip-cord and loudspeaker cable for portable/temporary hf Loudspeaker output operation up to 21MHz, pointing out that his worst-case loss R4 isn liggh-paSS was of the order of 0-9dB which, while not comparable with Si 1W Corn Stereo RG-8/U cable, "is a figure I can certainly live with". He ad- — 0 headphone mits that the unknown impedance may present problems, and output

he has made some tests which indicate that typically this is Low-pass around 1002 and provides a good match to most real antennas at modest height. Audio from receiver Before coaxial cable became readily available in the 'forties, 47/1 5611 many amateurs regularly used electric flex to feed dipoles, or frt for "link coupling" between those widely separated stages of Fig 10. G4BWE's simplified stereofilter using passive cross-over the old rack and panel transmitters. But one soon found that network some cables when used as a link connection on 28MHz failed to deliver more than a small part of the drive even when the cable was only 2-3ft long. Different types of cable could give very signal is being presented to each ear. However, if the balance different results. control of the amplifier is rotated from left to right, the sound Some amateurs even constructed their own coaxial cable appears ro glide in sympathy, moving steadily from one side of using beads as spacers, plus what must have been a great deal of the listener's head to the other as the relative amplitude of each patience. stereo channel is altered. The real answer to low-cost transmission line, at almost any "If an audio filter network consisting of separate high-pass frequency, is open-wire line, including in this category and low-pass sections is interposed between the receiver and a punched-out 3002 ribbon cable or its commercial equivalent, pair of stereo headphones, it is possible to distribute the energy such as the Swedish cables made by Borens Fabriks AB (Bofa) of the audio spectrum so that, for example, as the pitch of a cw which can have a loss of less than I dB/30ft even at 500MHz. note rises, so the signal will appear to travel from left to right. Most large commercial hf installations, where antennas are The situation is less complex with headphones than with often located hundreds of feet away from the station building, loudspeakers, where each ear will hear some sound from each continue to use open-wire systems (often of the four-wire type) speaker. To obtain this effect on headphones it is necessary and restrict the use of coaxial cable to the final distribution cir- only to feed the right headphone through a high-pass section cuits within the building. Long runs of coaxial cable represent and, conversely, the left transducer via a low-pass section; in an increasingly expensive way of losing rf power and other words a 'cross-over filter' as used in hi-fi practice to feed significantly reduce the flexibility of an antenna system, as signals to 'woofers' and 'tweeters'. indicated in the earlier item "Beam with multi-band element". "Fig 10 shows such a simplified 'stereofilter'. CI in conjunction with R I and R4 form a first-order high-pass network; C2 and R2 provide low-pass filtering for the other headphone. R I plus R4 and R3 plus R5 form potential dividers which not only G4B WE's simplified stereofilter attenuate the output but also provide a necessary degree of Many readers will remember the elegant form of audio signal isolation between the filter function and the headphones. The processing (the "stereocode") developed some years ago by stereofilter will thus be compatible with stereophones having Dud Charman,G6C.I, and R. Harris, G3OTK, as first des- driver impedances in the range 8 to 20002/channel when fed cribed in TT(August 1973) and with full circuit details in Radio from a low impedance loudspeaker output socket. Si is a Communication September 1975, pp674-81. The stereocode loudspeaker/phones changeover switch; while S2, when closed, enables a form of "stereo image" to be synthesized from results in a 'mono' output and, by doing so, provides a vivid incoming signals, and these are then presented to the listener as demonstration of the effect of the stereofilter!" though a small portion of the band was spread out in front of G4BWE built his unit in a small plastics case using non- him. There can be little doubt that this form of signal process- electrolytic capacitors throughout; however, reversible elec- ing helps an operator to really dig down among interference trolytic capacitors of the type used in loudspeaker crossover and pick out the wanted station. However, the use of a number networks could be used for C2 (4.7µF). He makes no of all-pass filters to form an analogue phase delay line makes extravagant claims for this simple form of sterofilter, and the system fairly complex to implement. advises some experimentation with component values if, in- Stephen Price, G4BWE, has been investigating a much itially, the stereo image appears to be "unbalanced". It will be simpler way of synthesizing a pseudo-stereo presentation, based appreciated that the "bandwidth" of the receiver depends entirely on amplitude and not worrying about phase. He upon many factors, such as i.f. selectivity, and this type of writes: filter is not intended for use with the sort of highly-peaked cw "Although relative phase, or time delay, is undoubtedly an signal resulting from narrow i.f. or al filtering. However, important factor in the operation of the complex mechanism G4BWE considers that this form of design can be justified on by which the brain determines direction, or 'localization' of the grounds of extreme simplicity; the unit requires no power sound, it is true also that amplitude plays a major role. supply and no complex "setting-up" procedure and, finally, A simple experiment to illustrate this may be carried out using a not only makes cw listening more enjoyable but can enhance domestic hi-fi system: if the amplifier is switched to 'mono' reception of almost any transmission, even ssb (although it and a programme monitored on stereo headphones, the sound must sound a little as though the operator at the other end will appear to be positioned at the centre of the listener's head, dashes across the room everytime the pitch of his voice due to the fact that equal amplitude, or proportion, of the rises—or perhaps I have got that wrong—G3VA).

RADIO COMMUNICATION May 1979 427 International Conference 300— on Antennas and Propagation 100— Z by L. A. MOXON, G6XN* o-

2 kilometres paper emitted "High frequency antennas and propagation modes in relation to the amateur service" was A Fig 1. Profile of the Balmeanach site presented by the author on behalf of the RSGB, at the Interna- tional Conference on Antennas and Propagation held at the IEE on 28-30 November 1978. was suggested that, in fact, most amateur communication over The author pointed out that amateur requirements for high very long distances takes place via chordal hop modes. frequency communication differ considerably from those of Antenna projects described by the author included: other services, and these generate a number of interesting (a) Development of very small beam arrays, down to 10ft antenna problems for which he had been seeking improved square for I4MHz, using large end-loading capacitances solutions. The differences also involve propagation, since the with neutralization of the resulting excessive coupling be- amateur is not interested in maintaining contact for long tween the elements, as described in Technical Topics, periods over a particular link but tends rather to take advan- February 1977 and June 1978. It was pointed out that most tage of the prevailing opportunities, with perhaps a bias amateur beams employ close-spaced elements and thus make towards the longer distances. Reflecting his own interest in this use of a subtractive method of beam formation, in contrast field, the author presented the results of observations over the to the additive principle which is applicable to large arrays. long path to Australia, which tended to prove that such prop- As a result they exhibit all the characteristic features of agation normally makes use of chordal hop modes without "supergain" arrays and should be so regarded. intermediate ground reflections. (b) Multiband operation without traps was described, using In support of his belief that chordal hop propagation can the "disappearing inductance" principle as featured in involve a considerable degree of ionospheric focussing, pro- Radio Communication, April and May 1977. It was pointed vided the angle of radiation is low enough at both ends of the out that this type of resonator, Fig 2 (a), has the particular path, the author reported the results of some tests he had just merit of allowing any conductor to be tuned to, or away completed, operating with low power equipment from steep from, a given frequency without cutting into the conductor; ground slopes. These tests were conducted in conjunction with this allows one to use masts or rigging as antennas, and can VK3M0, who was known to have achieved an abnormally low also be used to overcome nulls in the radiation pattern of an angle of radiation which had been confirmed by measurements antenna caused by the presence in its vicinity of other from an aircraft. There was evidence that for best results a resonant metal structures. steep drop of at least 700 to 800ft would be required, together A new version of the linear resonator. Fig 2 (b), was with an unobstructed horizon. described. This provides operation on three frequencies Such sites are difficult to find, but one near Balmeanach on without the use of relays, and is somewhat simpler than the the Isle of Mull, point A in Fig 1, appeared to be suitable. Bad methods described in the original article. Cl and C2 provide weather made it necessary to operate from the lower point. B, resonance at 28 and 21MHz respectively but, although lower but, despite this, ssb voice communication was established with frequency resonances are not much affected by higher ones, VK3M0 using 3W p.e.p. into an inverted-V dipole at 20ft in the absence of C3 the path via C2 acts at 28MHz like a above the slope, and it was maintained down to a p.e.p. of only 25mW. A further test some days later from a site in the Lake District, very similar to A. produced a result judged to be 2 about 10dB better, consistent with the expected height gain, A though unfortunately there was no provision for reducing the power to 2.5m W! (a) C — e-11—e— j Even on least favourable assumptions this would indicate a total path loss comparable with the free space value, suggesting enough focussing to offset any D-layer absorption or other losses in the ionosphere. The likelihood of focussing is known A to be greater the lower the angle of incidence at the ionosphere, C2 and it is applicable only to chordal hop modes since, with con- (b) ventional multihop propagation, any focussing in the ionosphere is offset by defocussing at the ground reflections. It 9 - 7 1 II C3 C3

•I Stoner Hill House, Froxfield. Petersfield, Hants. Fig 2. Two versions of the resonator

428 RADIO COMMUNICATION May 1979 shunt inductance which is varying with frequency, and this was soon obvious that nothing could be done without skeds. results in a very narrow bandwidth. The capacitors C3, There was little chance of keeping these except from relatively which are relatively non-critical in value, form additional inferior locations, accessible by car and falling a long way short linear resonators which remove the effect of C2 at 28MHz. of the specification which provided the main purpose of the- (c) Antennas for low heights. It was mentioned that a clx exercise. capability more or less independent of height can be achieved Several such expeditions were made, and requests by G6DW by the use of arrays of very short end-loaded vertical dipoles. to VK stations, asking them to listen for the author on the off. (Details of such a system for 7MHz are given in the Radio chance that he might be on frequency, resulted in contacts with Communication Handbook, Vol 2, p12.67.) VK3AD and VK3A0F. One other contact was obtained with VK6GU by gate-crashing his sked with G2MI. Meanwhile, by The story behind the story correspondence, and with some help from G4GI, the author A non-technical description of how the tests in September/ had come to an arrangement with VK3M0 which resulted in October 1978 were carried out was not included in the paper, four contacts (100 per cent success), including the two contacts but is appended here because of its possible interest to those featured in the IEE paper. It is possible these may constitute amateurs who enjoy outdoor activities. some sort of record, as communication was maintained down The weather in Scotland in September/October 1978 was to 25m W p.e.p. with (from the better location) something in quite apalling, and made it virtually impossible to be in the hand, although this was not the purpose of the exercise. The right places at the right times. Occasionally there would be a idea was that reducing the signal to the noise level at VK3M0 brief pause in the rain and gales, and the author would dash up would provide the best chance of obtaining a meaningful the nearest west-facing slope, hoping to repeat his successes of estimate of the path attenuation. 10 years ago ("Pocket-portable phone dx", Radio Com- The final test, which alone fulfilled the main purpose of the munication November 1972, pp724-7) — but no luck, despite exercise, proved a bit of a cliff-hanger in more senses than one! having three times as much power! The author and his xyl had pitched camp the night before near One of these locations was quite interesting, with the antenna Silecroft in the Lake District, about three miles from the foot spanning a ravine below a waterfall. It had to be "walked of the desired slope and beyond a level crossing with no other down" by crossing and re-crossing (as he was single-handed) access. Then they learned, by the merest fluke, that the cross- the swollen stream above the waterfall. Reception excellent, ing was being closed from midnight for work on the but no dice! line! Problem, to be "on location" with the antenna erected by What this proved was the extent to which competition from 0730gmt, starting with a 20min walk to the crossing and a Europe has increased in recent years. Invariably any strong sta- climb on foot of 700ft after driving to the foot of the slope. tions called would reply to some other G or European, and it Luckily it stayed fine!

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RADIO COMMUNICATION May 1979 429 It becomes news Now it can be told — By this time the affair had become a talking point among the local amateur fraternity, and it was not long before the local press scented a story. The sub-editors had a field day, produc- the Fareham "saga" ing such journalistic gems as "Radio Ham Fisted", "Beef over Radio Hams" and "Radio Hams Get the Cold Shoulder". Ugh! Meanwhile the Society had written a "background" letter to the council and had requested a personal interview for by J. W. SWINNERTON, G2YS*, two representatives to discuss the case. It was finally agreed that they should meet the chairman of the Housing Committee member, Interference Committee and the housing manager, and in October 1976 the author and Geoff Gwilliam, G4FJO, (representing local amateurs) went to the council offices—to find themselves faced by two coun- cillors and the council's solicitor in addition to the two officials MUCH of the work of RSGB committees goes unreported, they had set out to meet! The meeting might best be described either because it is of a routine nature or because it relates to as polite but profitable, thanks greatly to the skill of G4F10 in delicate negotiations, when to "tell all" would be inopportune putting the local point of view, while G2YS put the Society's and damaging to the interests of members as a whole. Members case. The upshot was yet another return to square one, and a complain from time to time that the Society is either unaware promise to consider sympathetically a request for the erection of a problem or is pursuing a deliberate policy of "masterly in- of a wire antenna. activity". However, the anti-amateur lobby was by no means content The following is a brief account of just such a problem which to let the matter rest, and there was a danger that the situation has engaged the efforts of the Interference Committee and might deteriorate into a vote-catching exercise, since the Post others for almost five years. Two years after negotiations Office investigators had advised receipt of no fewer than 36 began, the matter was "discovered" elsewhere in the amateur complaints-4I of them in communal accommodation and 15 radio press and was written up into a "story" with statements from council and private residents. It must be said, however, that were often very far from the truth. The following is an that the attitude of the PO officials was exemplary; they attempt to set the record straight and to suggest what lessons reported that on their visits to [he amateur he appeared to be can be learned from a very protracted dispute. conforming to the licence conditions, and they set about the enormous task of improving the situation. Fortunately they cleared the 41 "communal" complaints at one go. by upgrading the tv distribution system to 625 lines and fitting appropriate filters. Of the remaining IS, 13 complaints were The saga opens due to malfunction of the tv, one failed to show any symptoms and one proved to be an electronic organ. The story centres on an amateur in the Fareham area of Hamp- shire, the occupant of a council house. In 1974 he received a letter from the housing manager alleging that his transmitting Practical help activities were resulting in interference to neighbours' enter- The contribution made to this happy state of affairs by two tainment equipment and that this was in contravention of the local amateurs cannot be underestimated. Peter Martinez, terms of the tenancy agreement. Furthermore, the attachment G3PLX, and Fred Robins, G3GVM —both highly qualified of a wire antenna to the house had been made without the radio engineers—gave up a lot of their spare time to assist, by authority's prior knowledge or approval. On examination, the curing several awkward cases, in the course of which they tenancy clause invoked proved to be one stipulating that the found at least one equipment that was potentially lethal! Yet if tenant should not "cause annoyance to neighbours"—a general some reports elsewhere are to be believed, these two amateurs and wide-open dictum framed with a very different purpose in personally cured 40 cases of tri! mind, but to the layman capable of acting as a restriction on However, we were not yet out of the wood. Filters could be amateur radio. Indeed, the amateur was instructed to "cease removed: sets changed, or even re-positioned; other sources of transmitting"; non-compliance and failure to remove the interference could be put down to "that amateur", and stories antenna would lead to the service of an eviction notice. of interference problems still persisted. The amateur then appealed to the RSGB for help, and the case was referred to the Interference Committee. The first reaction was to play it cool and to start again from square one, by Council reactions removing the antenna as demanded and then submitting a for- Two developments came out of this: first, planning permission mal application to the council, as local planning authority, for was refused for a wire antenna on the grounds that interference an installation which was mechanically and electrically safe. It was still being caused, and second, the Fareham Council decid- was now 1976, and the council asked the tenant to agree to an ed to seek the support of the Local Authorities Association for extension of the statutory time for considering the application an amendment to the regulations placing responsibility on the because it was unable to reach a conclusion. Naturally the amateur for any incidence of interference however it arises, amateur chafed at the delay, and in the meantime put up a tem- and giving affected persons the power to seek redress. This porary antenna pending a decision. This resulted in a peremp- resulted from a resolution put forward by the Policy & tory order to remove it or quit. Resources Committee of the council at a meeting attended by the then RSGB regional representative. Les Hawkyard, G5HD. 29 Beacon Way, Rickmanswonh. Hens wD3 2PF At this meeting a councillor appeared to spring to the

430 RADIO COMMUNICATION May 1979 amateur's defence, but afterwards he voted for the resolution! Relief may come in the ultimate upgrading of EEC standards The matter was given a full report in the Southern Evening of immunity to breakthrough; at present our own electronics Echo which not only gave good coverage to the amateur point industry often accepts standards which are deplorably low for of view but also took the trouble to approach the RSGB direct- the sake of saving a few pence. There are grounds for hope, ly for its comments. Full marks, Echo! The paper did report and at least one British tv manufacturer is becoming the view of a local councillor that the affected amateur "had "breakthrough-conscious" with commendable success. no consideration for the misery he was causing residents . . . the law was biased against millions of tv owners". The resolution was sufficient, however, to excite the interest Lessons learned of the local MP, who went on record as saying "these com- What are the lessons to be learned from this prolonged and plaints must be listened to . . . a person must be stopped from sometimes acrimonious dispute? In the first place, the amateur being a public nuisance". Again, alas, the layman's error of must show that he is not alone; he is in danger of isolation taking an effect for a cause, and blaming the poor radio unless he is a member of RSGB and seeks its advice and sup- amateur! However, the MP's interest also prompted "Radio port at the earliest opportunity. It is dangerous to wait until a Solent" to feature the controversy in its programme of local situation gets out of hand and then ask for help—the road to a affairs, when a local councillor and two neighbours—one hav- solution is then that much harder. Second, if a member does ing trouble and another whose problems had been cleared— seek help, he is often too close to the problem to "see the wood were interviewed; here at least was an endeavour to give factual for the trees" and is emotionally involved—any advice which and impartial reporting. The Society's advice to the amateur the society gives is based not only on the wider interests of its was not to allow himself to be interviewed, on the grounds that members as a whole but also on a detached view. It is no use its case could not adequately be set out in a brief and somewhat "keeping a dog and barking oneself", and once the matter has superficial discussion. Several members were kind enough to been thoroughly thrashed out with a member he must place his furnish a transcript of the broadcast. trust in the Society's policy and do or say nothing without prior consultation—an ill-timed comment or letter can place a favourable solution in jeopardy. In the third place, the Society RSGB efforts continue has contacts and advisers who can be of material assistance, Meanwhile the efforts of Peter Martinez and Fred Robins con- and it is often to the ultimate benefit of the case to negotiate in tinued unabated. Early in 1977 they met three Fareham coun- strict confidence. Do not assume that the Society knows cillors for a frank discussion, and were able to bring their own nothing and does nothing: often patient enquiries are made trouble-shooting efforts to a successful conclusion. Meanwhile more difficult by ill-informed criticism. the MP was complaining that his enquiries to the Home Office Anyone who meets an amateur who says "I don't think its appeared to have fallen on deaf ears, while the council learned worthwhile joining RSGB" or "I don't agree with the RSGB from the Local Authorities Association that the problem ap- policy/organization/lack of this or that" etc, should be asked peared not to be widespread enough to warrant using its in- "Can you afford not to be a member?" The case outlined fluence. So, as a result of local and national efforts to ride out above is typical of the extent to which a considerable amount of the storm, it appeared that it was now abating. voluntary time and work (amounting to hundreds of man- The upshot was that the council now proposed a "one-off" hours), backed by the monetary resources and facilities of the tenancy agreement applicable to the amateur, and this the Society, have come to the help of one member. In addition the Society referred to its legal adviser. His opinion was that it Society has enjoyed the confidence and support of the Home should be amplified and amended to safeguard the amateur in Office whenever it has been called upon, and has had the circumstances where he was patently not to blame. This was benefit of legal advice of the highest order. submitted to the council's solicitor, and the point was also The case has thrown up one aspect of legislation currently in made that such an amendment should be standard to all force which has implications wider than the field of amateur tenancy agreements, not only in equity but also in view of the radio. Local councils act as agents of the Department of the expansion in the amateur population and even future possible Environment in planning matters, and where a council deals legalisation of some form of citizen's band. with tenants of its own property it is as it were "wearing two The council agreed to the amendment, and also sought the hats". The planning and housing departments may well occupy Society's advice on the technical aspects of a suitable transmit- adjacent offices, and this would seem to facilitate the rein- ting antenna to be permitted. Obviously the efforts to contain forcement of the policy of one by the other. An amateur with a the problem had paid off: the patience and firmness of the council tenancy could well suspect that a difference of opinion negotiators at national and local level had borne fruit with the with the housing manager might be affecting his planning admission that the amateur had successfully maintained his application for an antenna system. Any member who has such position. suspicions is invited to supply full details to the Society. There, for the time being, the matter rests. The council has elected for reasonableness instead of confrontation, and its representatives have gained some understanding of a technical Acknowledgements problem solved by patient investigation rather than by emo- The Society would like to record its grateful appreciation of the tional appeal. One result has been that the Society has work done by Les Hawkyard G5HD, Peter Martinez, G3PLX, prepared, and distributed to all local authorities, a leaflet Fred Robins, G3GVM, and Geoff Gwilliam, G4FJO, at local which sets out in simple terms the problems and the procedure level; of the many members who—entirely unsolicited—sent in for solving it. Any amateur in similar difficulties should ask for newspaper cuttings and photocopies, or who made transcrip- this leaflet to be referred to, or obtained from the RSGB if it tions of the "Radio Solent" broadcast; and finally of its legal has become buried in the masses of paper now manifest in local adviser, who by professional custom has to remain government. anonymous.

RADIO COMMUNICATION May 1979 431 Reception and processing of TIROS-N weather satellite telemetry

by J. GILBERT , G4CEB , and T. J. TERRELL, DipEE, MS c, PhD, CEng, MIEE *

(Part 2)

Transmitted signals and their reception (flip-flops) to the frequency of the required scan rate. This timebase is 2-0Hz for production of both video channel pic- (continued) tures, which are transmitted side by side in the case of TIROS- N. Another frequency is available, namely 4Hz, which is used Processing the received signal for reproduction of single channel pictures and those transmit- This section discusses the production of a weather satellite ted by other satellites at the 4Hz scan rate. picture, using either a previously recorded signal or a signal The selected frequency is then fed to the timebase circuit received during a "real-time" pass of a satellite. Fig 11 shows which produces a sawtooth waveform output, triggered by the the block diagram of the receiver's display electronics. The input pulses. When connected to the display equipment the line system outlined is purely electronic, and each individual scan of the picture frame is reproduced. The horizontal move- system-block and the overall display system is briefly dis- ment of the satellite is created by the Y-axis timebase circuitry. cussed. This is a conventional operational amplifier set as an integrator Referring to Fig 11 it is seen that the recorded signal of with a very long integration period. Fine adjustment of the line 2,400Hz, derived from the crystal oscillator, is fed to a pass- separation is achieved with the use of a multi-turn poten- band filter circuit which is tuned to 2,400Hz. The limiter stage tiometer set to vary the integration ratio of the circuitry. By is used to clip the signal to a level suitable for input to the pli. discharging the integration capacitor the line scan is reset to The internal oscillator of the pli is set to a frequency in the line No 1 of the frame and further pictures can be produced. range 2,380Hz to 2,420Hz, which enables the input signal to be The scanning system has thus been arranged for the produc- locked in phase within this range. Since the recorded signals tion of a picture. Since the X-timebase has been derived from will not be played back at a constant 2,400Hz, due to wow and the synchronizing channel of the tape recorder, this signal be- flutter of the tape, the output of the pll will follow precisely ing locked by the pli, any variation in tape speed will only slow any changes of the input frequency. The output of the pli is a or quicken the scan rate, but the scan will still be in sync with 2,400Hz square wave which is divided by conventional ttl logic the telemetry channel as both tracks arc recorded simultaneously. The display device is an oscilloscope having a storage

*School of Electrical and Electronic Engineering, Preston Polytechnic, facility. The demodulated telemetry is fed to the Z-input of the Preston PR I 2TQ oscilloscope; as the signal is amplitude modulated the intensity

Sync Sync pulse Signal conditioning detection filter circuitry logic Demodulated H satellite A telemetry input or recorded o —ii 2400Hz 2400Hz sync • band-pass Amplitude PLL lie 1 Division OD limiter (2400Hz) logic channel filter y 2Hz t 1 4Hz

Z-modulation Control and line X-timebase Y-timebase conditioning blanking logic circuitry circuitry

z Display Y device

Fig 11. Block diagram of equipment used to process the received signal

432 RADIO COMMUNICATION May 1979 A similar procedure can be used for the processing of picture information received from "geostationary satellites". lf a satellite is placed in an equatorial orbit at a height of approximately 35,000km, the orbital period will be that of the earth's rotation. Thus a satellite can be placed at a particular point in the orbit and "parked" at that location with respect to the earth. In this mode the satellite is said to be geostationary. Transmissions in the form of wefax (weather facsimile experiment) are widely available from several geostationary satellites located at various positions above the equator, and the wefax pictures can be of various formats. The TIROS-N polar orbiting data can be received after being regenerated by computers at the World Weather Building, located near Washington, DC, USA, and in this form the polar satellite cloud cover pictures are superimposed on standard wefax grids of latitude and longitude, including outline maps of the larger land masses. Pictures of greater sections of the earth and tropical quadrants are transmitted at specified times during the day, these being detected by the geostationary satellite. Typed formats giving bulletins on schedules and information details are sent regularly. Wefax telemetry is in an analogue a.m./fm form similar to Fig 12. The pli slip/lock facility showing an example of a change of picture phasing started at "A" and locked at "B" that used on the vhf downlink for TIROS-N (171. A single image at a time is sent with a scan rate of 4Hz. The European meteorological satellite Meteosat 1181 transmits experimental wefax at frequencies of 1,691.0MHz and 1,694 5MHz, these of the spot will vary with the applied modulation. Thus the being for southern and northern hemisphere data respectively. spot will be light when cloud or ice formation is real, and dark Other geostationary satellites, many operated by USA agencies for land or sea. With the system in operation a reproduction of 1171, operate at a frequency of 1,691 .0MHz for wefax. the satellite scanning mechanism is observed; this produces a When receiving signals from geostationary satellites, a fixed cloud cover picture of the area the satellite traversed. antenna system is used, beamed for maximum signal strength. In order to separate the infra-red and visible pictures as The elevation angle in Britain for these satellites is usually quite single frames the 4.0Hz line scan should be used; at this setting low (for sms wefax an elevation of less than 15° is required and the line scan will be of a single video channel. Line blanking of may necessitate a larger than 2m dish for usable signals in cer- the unwanted channel must be enabled to prevent interlacing of tain areas), thus the use of high-gain antennas with signal the two pictures—this can be achieved by several methods. For preamplification is advisable. example, a line blanking circuit could be placed as shown in Fig 11; the triggering of this circuit would be at 4.0Hz, which would blank every other half line and thus remove the picture Picture interpretation not required. Another method is to set the oscilloscope controls Figs 13 and 14 are examples of weather satellite pictures pro- in a way that also blanks one of the pictures. If the X-timebase duced using the equipment described earlier in this article. is kept at 2.0Hz but the sensitivity of the X-input doubled, These prints are of TIROS-N imagery recorded on 29 October then only half of the 2 -0Hz scan will be displayed. This method works very well in practice but the results depend on the availability of an oscilloscope with the necessary controls. The slipping of the pll in the display electronics enables the required channel to be centred on the screen. Once in position, the lock is again engaged and the picture will be displayed. Fig 12 illustrates the operation of the slip-lock facility of the pli circuitry. The quality of the produced picture also depends on the display device having a spot with a very small area, because of the small size of the oscilloscope screen. Typically, the 5103N Tektronix oscilloscope has a low spot size to screen size ratio, and is suitable for the display device. The storage facility is useful for setting the timebase to give good line definition. However, most storage oscilloscopes tend to have some display "flair", thereby reducing the picture definition. This effect is particularly bad when the cloud (white) portions of the picture tend to spread into a wide uninterrupted area. Thus, in order to obtain a picture of good quality, the storage facility may be dispensed with once the oscilloscope timebase has been initially adjusted to give a good line scan; the spot is then allowed to trace the picture on to a photographic film. Fig 13. Typical TIROS-N imagery (recorded on 29 October 1978)

RADIO COMMUNICATION May 1979 433 Acknowledgements The authors are indebted to NASA for supplying data and photographs, some of which, by their kind permission, are reproduced in this article. The help and co-operation of the Home Office Radio Regulatory Department in providing the statement concerning the special receiving licence is acknowledged. Finally the authors would like to thank Preston Polytechnic for providing some of the facilities that helped to make this project a success.

References 111 Artificial Satellites, M. W. Ovenden. (A Penguin book, 1960). 121 Artificial Satellite Observing, edited by Howard Miles. Faber and Faber Ltd. 131 "Just look at the weather, Part 1: The reception of automatic picture transmissions from satellites", P. W. Fig 14. TIROS-N imagery (recorded on 29 October 1978) showing day to night transition Sollom. Radio Communication November 1971. 141 "Just look at the weather, Part 2: Making pictures from the apt signal", P. W. Sollom. Radio Communication December 1971. 1978. Fig 13 shows the cloud cover over western France, the 151 "Receiving weather pictures from satellites, 1: A very sim- UK and the eastern Atlantic. The French coast appears in the ple receiving station", J. M. Osborne. Wireless World October lower right of the print, most of the UK is obscured by 1971. cloud—the Cornish coast and parts of East Anglia being the (61 "Receiving weather pictures from satellites, 2: A more only cloud free areas. The signals were recorded as dusk was complex station which provides better quality pictures", J. M. falling over England; this is shown by the light intensity varia- Osborne. Wireless World November 1971. tion across the image (the sun is illuminating the scene from the 171 "Satellite reception made easy, Part 1: General principles west—left-hand side of print). and aerials to use", J. M. Osborne. The Short Wave Magazine, As the satellite travelled farther north it passed from the Vol 28, February 1971. illuminated side of the earth to that in shadow. This transition (81 "Satellite reception made easy, Part 2: Basic understan- from day to night is clearly seen in Fig 14. The low angle of the ding about satellite orbiting—fixing pass time and direc- sunlight with respect to the cloud tops highlights top surface tion—current satellite data", J. M. Osborne. The Short Wave details at the day/night zone. The cloud in the left section of Magazine, Vol 29, March 1971. this print is well lit by the sun, while that to the far right is in 191 "More about satellite reception, Part 3: Making the wx complete darkness. The top surface of the cloud does not picture from the signal", J. M. Osborne. The Short Wave appear "flat" any more, "gullys" and "peaks" of cloud grad- Magazine, Vol 29, July 1971. ually emerge. Long shadows from high ridges of cloud are cast 1101 "Weather satellite ground station: Reception of cloud far into the east. The two white markers on the right of the cover pictures transmitted in the I36MHz band", G. R. Ken- print are, in fact, the minute signals contained in the telemetry nedy. Wireless World November 1974. format. Both pictures are from the same pass of the satellite 1111 "Weather satellite ground station-2: Reception of and represent the earth as seen in the visible light spectrum. cloud cover pictures; limiter and phase-locked loop system", G. R. Kennedy. Wireless World December 1974. 1121 "Weather satellite ground station-3: Conclusion of this Conclusion series with the display electronics described in full", G. R. Ken- The major points concerning the setting up of a satellite receiv- nedy. Wireless World January 1975. ing station have now been outlined. Details of practical cir- 1131 "The phase-locked loop", J. M. Osborne. The Short cuitry for the individual units have been omitted because there Wave Magazine, Vol 30, March 1972. are many articles and books (see reference list) dealing with 1141 Phase Locked Loops, Signetics Corporation. Mullard similar items. The basic differences in requirements for a Ltd, Mullard House, Torrington Place, London WC1E 7HD. TIROS-N system and those previously written about should be 1151 The Public General Acts and the Church Assembly considered when designing equipment. Measures of 1949. Chapter 54, Vol 1. HMSO 1949. By the end of 1979 the second satellite of the new third 1161 C. L. Maskaleris, Mission and Data Operations Direc- generation, of which TIROS-N was the prototype, should be torate, National Aeronautics and Space Administration, Code operational. Two satellites are to be operated simultaneously, 512. Goddard Space Flight Center, Greenbelt, Maryland providing a southbound equator crossing at about 07301st and 20771, USA. a northbound equator crossing at about 15301st. 1171 Weather facsimile—a direct broadcast service from the Keeping up to date is vital for anyone interested in any of the SMS/GOES meteoroligical satellite. NOAA, National En- aspects of weather satellite reception, and to this end the vironmental Satellite Service, Washington DC 20233, USA. authors hope that this article has helped the reader to achieve, 1181 Meteosat programme is. run by: ESA, 8-10 Rue Mario to some degree, this aim. Also it is hoped that readers who Nikis, 75738 Paris Cedex 15, France. knew little of the practical aspects of such a project now have a 1191 VHF! UHF Manual. The Radio Society of Great Britain, basic understanding of how to tackle the associated problems. 35 Doughty Street, London WCIN 2AE.

434 RADIO COMMUNICATION May 1979 • It is difficult to cite any one of his contributions in particular, as Mike has made so many in recent years! One of the microwaves most noteworthy of course is his development of the loop-Yagi antenna, which has been so successful that it could now be said to be the standard antenna for I • 3GHz. He is one of the Charles Suckling, G3WDG pioneers of regular dx communication on I • 3GHz using troposcatter, and his operating philosophy on this band stimulated 1979 RSGB National VHF Convention many other stations to achieve similar successes. He has always The lecture stream organized by the Microwave Committee at been ready to report his activities, and has contributed regular- this year's RSGB National VHF Convention was, as usual, ly to Radio Communication through this column over the very well attended. In the first lecture. G3WDG described years, including recent designs for high performance lOGHz simple, yet very effective techniques for getting the best pos- filters, and a lOGHz transmit/receive converter for cw and ssb. sible performance out of a receiving system. A brief review of the factors governing receiver sensitivity was given, and the Narrow -band tests on 10GHz most important points made were: (a) a preamplifier must have Don Hayter, 03.1HM, (Four Marks) has recently joined the sufficient gain to over-ride the mixer noise, and that for ranks of lOGHz narrow-band operators. He is using the microwave receivers it is usually necessary to have at least two G3JVL mixer (described in Microwaves January 1979) and has stages of amplification before the mixer; (b) feeder losses been very active since getting it operational. His first test was degrade sensitivity more seriously than might be expected and, on 24 February, with G3JVL. Signals were very strong, and to avoid this, preamplifiers should always be mounted at the this gave Don his first opportunity to hear ssb on lOGHz. On masthead; (c) in the case of wideband mixers, a filter is the following day he travelled to Hindhead Common, and necessary between the preamplifier and mixer to reject noise copied G3JVL at 10dB above noise over the 40km obstructed from the preamplifier on the image frequency. path to Hayling Island. Tests were also carried out from this In the second half of the lecture, G3WDG emphasized the site over an optical path with G3BNL/P and G8ASP/P, who need for an automatic noise figure optimization aid for setting were operating from Old Reading, near Stanmore. G3BNL was up preamplifiers and mixers, and recommended the G4COM heard S9 on narrow band, as was G8ASP on wide band. design (Radio Communication January 1976). This device was G3JHM then moved to a site near Farringdon, and copied shown working, being used for setting up a 1 OGHz receiver. readable signals from G3BNL over the two-obstruction path. The measurement of noise figure using ground noise and On I March. using a newly-acquired gasfet preamplifier. hot/cold resistors was also described, and the latter technique G3JVL was copied for the first time over the very difficult path demonstrated with a 432M Hz gasfet preamplifier connected to from G3JHM's home QTH. On the following day, operating resistors at room temperature and at - 196°C. The 4cIB change portable from a site along the G3YGF-G3JVL path, both sta- in noise level was clearly audible as the preamplifier was swit- tions were copied in QS0 on ssb. Success was also achieved ched between the two resistors. over the badly-obstructed 91km path between Oxford and The second lecture was given by G8DEK, who reviewed the Butser Hill, in the form of a crossband I OGHz-144MHz QSO. application of microstrip techniques to amateur equipment. Over this path, G3YGF's signals had the rapid-fading Various configurations of microstrip circuitry were described, characteristic of troposcatter, indicating that the path was so and it was shown how directional couplers, mixers, power poor that only the scatter signal was present. dividers, preamplifiers, power amplifiers and filters could all G3JH M has noticed that signals over one- or two- be constructed on copper laminate board using tools no more obstruction paths do not fade in this manner, since the scatter sophisticated than a razor blade and a ruler! It is a pity that signal is masked by the stronger, more stable, diffraction microstrip does not find a wider application in amateur equip- signal. Thus it seems that rapid fading is a good test to dis- ment, as the circuits are often much easier to make than the criminate between troposcatter and other forms of propagation. equivalent coaxial or waveguide circuits. Hopefully, after On 25 March the 85km path from Old Reading to Butser Hill G8DEK's lecture more people will be encouraged to try this was covered for the first time, when G3JH M heard G3BNL/P. interesting form of construction. G3BNL was using 150m W to a 2ft dish, and G3JHM was using The last lecture covered the subject of operating microwave the bare mixer and a 3ft dish. Thus there seems to be sufficient equipment in the field, and was given by G4CNV. He outlined gain in going to narrow band to enable obstructed paths to be ways of avoiding the problems which often result in unsuc- covered as a matter of routine, even without twis and cessful microwave tests, by carefully controlling the two preamplifiers, which is a significant point. G3JHM remarks variables—frequency and beam headings. Both these subjects that this improvement has enabled him to work over a lot of new were covered in some detail, as well as the engineering required paths which would have otherwise been impossible on wide to ensure success during a test. Path plotting beforehand was band. strongly recommended, as was the analysis of the success or The regular tests between G3YGF and G3JVL over the failure of a contact afterwards to point out the strengths and 1 I Ok in path between Oxford and Hayling Island are continuing weaknesses in one's equipment and technique. to bring forth some very interesting results. Instead of just carrying out tests at a fixed time (10pm) daily. it has recently 1979 Fraser Shepherd Award been possible to make a number of extended observations dur- The Fraser Shepherd Award, recommended annually by the ing the day, when signals, in general, seem to be stronger. In Microwave Committee in recognition of outstanding contribu- addition a number of enhancements of 10-15dB have been tions to microwaves, was presented at the RSGB National VHF noticed, and in almost every case these correspond to weather Convention this year to Mike Walters. G3JVL. fronts crossing the path. Indeed, the best signals often seem to occur in conditions of high winds and driving rain, not usually 31 Oakwood Road. Chandler's Ford. Hams SO5 ILW. considered ideal for microwave propagation! D

RADIO COMMUNICATION May 1979 435 The buffet and dance was again popular, with more than 100 members staying until late in the evening. During a break in the 4-2-70 evening's entertainment the following trophies were presented: the VHF Manager's Trophy to GM3W0J, the South of Scotland VHF/UHF Group; the Mitchell-Milling Trophy to Graham Knight, GM8FFX G3PMH, the March & D ARS; the Thorogood Trophy to L G3UNU, the University of Nottingham Group; the 1951 Coun- cil Cup to G3PMH/A; the Surrey Trophy to the March & D ARS; the Tartan Trophy to the South of Scotland Group, and the Hanson Trophy to Ron Thomas, BRS15822. Bob "Boogie" Burns and his nine-piece band lived up to RSGB National VHF Convention their name, with music which ranged from "Saturday Night This year's RSGB National VHF Convention again proved to Fever" to "Be Bop a Lula"—maybe next year he should be be a very popular event, with nearly 1,000 members attending billed as "Bopping Bob Burns". The band was certainly the the one-day event. The trade component exhibition was very most popular for several years, with dancing continuing until busy all day, and the RSGB bookstall was doing a roaring well after midnight. trade, especially in the new IARU QTH Locator Map. The Geoff Stone is to be congratulated on organizing yet another number of trade exhibitors, with such delicacies as 4CX250B very successful vhf convention—the venue has already been valves and holders, was larger than at previous conventions, booked for next year. and four were accommodated in an overflow exhibition in the adjacent Totton School—the venue for the lectures. The RSGB President, John Bazley, G3HCT, welcomed a record number of members to the afternoon lecture sessions. In New world record on 144MHz his opening speech the President reviewed some of the current At 1810gmt on 13 February, six months of effort by the Pretoria members of TESSA (TransEquatorial Study Group, vhf activities, and he was particularly pleased that the Society had been able to negotiate a licence for GB3PT, the rtty South Africa), attempting to make two-way contact on repeater. This had been the first time that the Home Office had 144MHz with the Mediterranean area, were rewarded with suc- issued a licence for a repeater to be specifically used for home cess. Dave Larsen, ZS6DN, assisted by Fred Anderson, ZS6PW, had a 15min cw contact with Costas Fimerelis. stations. He took the opportunity to remind members that the SV1DH, in Athens, on a frequency of 144-130MHz—at a basis for the licensing of all the other repeaters was primarily distance of 7,100km. The 144MHz signals from Pretoria were mobile use. first heard in Greece on 5 November 1978, and since that time a At the end of his speech, G3HCT presented Dave Price, special frequency on the 28MHz band has been constantly GW4CQT, with the first ever WAC Certificate to be issued to monitored during 144MHz schedule times so that both SV I OH an amateur for working all continents on 144MHz. Tom and George Vernadak is, SV1AB, could immediately report any Douglas, G3BA, the chairman of the VHF Committee, also reception of the ZS6DN signals. At 1803gmt on 11 February, presented GW4CQT with an inscribed tankard to celebrate a cw signals from ZS6DN on 144MHz were heard in Athens, and British station attaining the first 144MHz WAC. Greek amateurs attempted to reply. However, although the SV All the lectures drew large crowds, and some of the rooms station's signals were heard in Pretoria, no definite contact was were filled to standing room only. Three of the lectures were given by members of the Propagation Studies Committee, and established. At 1745gmt on 13 February, SV I DH reported on 28MHz that he was hearing signals from ZS6DN's beacon on G2FKZ, G3LTP and G3USF each had an audience of more than 150 members to hear their talks. Charlie Newton, G2FKZ, 144• 131MHz, and ZS6DN immediately went to the vhf shack the IARU Region 1 auroral co-ordinator, gave a detailed on his farm, switched off the beacon and established a two-way account of five different types of solar event which are QS0 with SV I DH. Signal reports were RS 52 at both ends of associated with auroral disturbances. Ray Flavell, G3LTP, ex- the 7,100km path—with no T-report being sent, even though plained tropospheric propagation in a very scientific manner, the contact was on two-way cw. No T-report fits the sound giving his audience an insight into the ways in which changes in heard at both ends of this record-breaking contact. Although pure cw was used, the received signals were distorted and the weather affect long-distance contacts on the vhf bands. accompanied by a "rushing" sound like band limited white Professor Martin Harrison, G3USF, played his audience some noise but centred on the bfo note. Attempts were made to use recordings of spectacular sporadic-E openings and reviewed ssb but these were unsuccessful, although it was obvious that the current theories on this unusual propagation mode. Grant the signals were there as the syllabic rhythm of the voice could Dixon, G8CGK, demonstrated slow-scan television and be heard, but the speech was unintelligible due to the showed his home-made digital slow-to-fast scan converter "rushing" sound. The contact continued on cw with 100 per which produced excellent pictures on a standard 625-line television monitor. cent copy until 1825gmt, when conditions deteriorated and the QS0 was terminated. The largest crowd of the day listened to Nigel Huntley, A further contact was made by ZS6DN on 16 February, this G4CDU, who demonstrated a Pet home computer linked to a time with SV1AB who is located 10km north of the SV1DH vhf station. G4CDU showed how the Pet could be program- QTH in Athens, thus breaking the record established only three med to receive and transmit cw and rtty, as well as assisting in days before, albeit by such a relatively short distance. This making up contest entries by calculating distance and scoring. OSO lasted from 1820 to 1830gmt and the reports exchanged Ron Whitby, G8MEI, spoke about the design and operation of were also RS 52 with signals again being accompanied by the rtty repeater GB3PT, which operates on RB12 from Barkway. "rushing"sound. On the same day SV8JE on the island of Kefallina, on the western side of the Greek peninsula, reported *PO Box 49. Aberdeen AB9,81A reception of the ZS6DN signals from 1800 to 1825gmt. SV8JE

436 RADIO COMMUNICATION May 1979 was unable to make a QS0, but this report adds a further 80km seem to go over their heads. Both 5B4WR and ZE2JV have to the distance covered by the ZS6DN signals. assumed in the past that the te circuit was symmetrical about On 5 March there was the longest opening so far between the geomagnetic equator, and this is confirmed to some extent South Africa and Greece on I44MHz. The opening started at by the SV to ZS contacts. He also notes with interest that the 1750gmt and ended at I 845gmt, and during the whole opening ZE2JV beacon is heard in Cyprus between 1600 and 1930gmt ZS6DN was in contact with SVIAB and SV I DH. The net was and that the SV to ZS contacts took place close to 1800gmt. also joined by Jack Anderson, ZS6LN, in Pietersburg, and the Les Palfrey, G4CQX, also writes from Cyprus, where he extremely long distance four-way QS0 lasted for almost an holds the callsign ZC4LP. He encloses a copy of the Cyprus hour. SV IDH was running 300W to a Jaybeam 14-el club newsletter which contains some of the above information Parabeam; ZS6DN used 100W to four 10-el Yagis, and SV1AB about 5B4WR and also the news that three other stations, used 200W to a Tonna 16-cl Yagi. 5B4AP, 5B4AZ and 5B4EI have also been copying signals Inspiration for all these experiments came from the suc- from the ZE2JV beacon on 144. 160MHz. Signals as strong as cessful I44MHz contacts between Ray Cracknell, ZE2JV, and S7 have been received from the beacon by these three amateurs, Roland Whiting, 5B4WR. ZS6PW and ZE2JV have been co- who join the swelling number of operators collating informa- operating in the study of transequatorial propagation for more tion on te propagation. than 20 years, and they must be given the credit for conceiving The dates of the te openings between Cyprus and Rhodesia, and planning the Pretoria to Athens experiment. The equip- and of the openings between Greece and South Africa, have ment and site for the South African end were provided by been sent to W1JR, W 1 HDQ and YV5ZZ. It is hoped to ZS6DN, and mention must also be made of John McCoy, publish a list of te dates for South American openings in the ZS6JM, who erected the antennas and made daily maintenance near future to see whether there is a definite co-relation with visits to the site to ensure that all the gear was kept in perfect the above dates. The tests on I44MHz between 5B4WR and working condition. Doug Hutchinson, ZR6JH, has liaised ZE2JV are to continue, and plans are in hand to try for trans- between the members of the South African group, chronicled equatorial propagation on the next band up-432M1z. the events as they occurred, and sent the 'details of their magnificent achievement direct to 4-2-70. The Pretoria Tessa Group is also to be congratulated on the Meteor scatter activity contest good publicity generated in the South African national press The Ghent VHF Activity Group led by Mark De Munck, for the record-breaking contacts. Ken Young, G3ZCG, who ON5FF, has organized an unusual contest to tie in with a has just returned from South Africa, has sent a copy of one of special 10-week ms activity period. Every amateur is invited to the newspaper reports, from a Johannesburg newspaper, which take part in the contest which runs from 0()00gmt I June to emphasizes the fact that amateurs are contributing to scientific 2400gmt I 5 August 1979. So as to encourage random ms opera- research by having contacts on I44MHz over distances which tion, points will only be awarded for contacts which are not seemed impossible to professional scientists. made by pre-arrangement. The contest also encourages correct operation on the ms calling frequencies by only giving points for contacts taking place off the calling frequencies; 144.100 Transequatorial (te) propagation and 144•200MHz can only be used for calling CQ on cw and A great deal of scientific interest has been expressed ssb respectively. throughout the world in the results of continuing experiments To be valid for the contest, cw QS0s must take place be- on I44MHz between 5B4WR and ZE2JV. Roland Whiting, tween 144.102 and 144•120MHz. These frequencies will be 5B4WR, has carefully recorded the times and dates on which identified by letters: 144-102 = frequency B, 144.103 = fre- he was able to receive the ZE2JV beacon signals in Cyprus, a quency C, etc to 144.119 = frequency S, 144.120 = frequency path distance of 5,978km. He was able to copy the beacon on T. 110 separate days in a 335-day period between April 1978 and Sideband working frequencies will also be identified by let- March 1979. Since the dates for the period April to October ters as follows: 144- 185 = frequency A, 144.190 = frequency were published in 4-2-70 (February 1979) many requests have B, 144-195 = C. 144.205 = D, 144.210 = E. 144.215 = F, been received for more information about this most unusual and 144.220 = G. long distance path which seems to be related to transequatorial Stations calling CQ on the random calling frequencies propagation. Roland Whiting has sent the following update on should use the following procedure: CQL ON5FF CQL the information published in February. The ZE2JV beacon ON5FF . . . for 5min, thus indicating that ON5FF will listen signals were copied in Cyprus on 3, 5, 8, 19 November; 10, 12 for replies on frequency L (144.112MHz in this instance), and December; 10, 16, 20, 25, 28, 29, 30, 31 January; 1, 2, 3, 4, 8, if anything is heard the QS0 continues using normal ms pro- 9, 10, 11, 12, 13, 14, 16, 17, 19, 23, 26, 27, 28 February; and on cedure. During the contest period operators can move location 1, 3, 5, 7, 8, 9 March. as long as the same callsign is retained. Scoring is five points Roland mentions the fact that the strongest signals were per random QS0, and stations may only be worked once in any received during February-sometimes exceeding 30dB above 48h period. Stations already worked in the contest score four Ii4V. Like SV I DH and ZS6DN, attempts have also been made points for a second QSO, three points for the third contact, to receive sideband signals over the path, but the rapid flutter two for the fourth contact, and one point for the fifth and all and fading has so far made voice signals unintelligible. With following contacts. Only completed contacts by random ms the lengthening of the te circuit in February to allow the SV-ZE propagation will be valid. No serial numbers shall be exchang- contact, he has been paying special attention towards South ed, and logs showing time, date, callsigns and reports sent and Africa, and has listened at times when contacts between received should be sent to ON5FF, Koning, Albertlaan. 9000 Rhodesia and Greece have been taking place, but so far no Ghent, Belgium. The station with the highest score will receive signals have been heard from ZS. 5B4WR and his colleagues in a specially engraved trophy, and all participants will receive a the Cyprus ARS are puzzled that these longer distance signals certificate and details of the contest results.

RADIO COMMUNICATION May 1979 437 information above: 6Y5RC on 50-025MHz. T12NA on 50- 080MHz, VE1SIX on 50.088MHz, FX3VHF on 50.104MHz, KH6EQI on 50.104MHz, and 5B4CY on 50-498MHz. This beacon information should only be taken as a guide, and vhf operators' attention is drawn to the paragraph headed "Beacon and repeater print-outs".

Oil field vhf operation Chris Tran, GM3W0.1, recently worked LA IEKO on the 3.5MHz band, and the operator gave his location as the Ekofisk Field in the middle of the North Sea. LAIEKO is the callsign of the club located on the field, and there are 15 operators who arc licensed to use this station. The club will be operational on 144MHz ssb and fm from June onwards once a suitable antenna has been installed. LA I EKO is located in BQ QTH locator square and is therefore ideally located for vhf contacts to G, GM, LA, PAO and OZ. GM3WOJ remarks that it would certainly add to the interest in the new RSGB QTH Squares Award if the other operators known to be on the For- OKIAIY/P, who is well known to British vhf operators for his outstanding 432IVIHz signals from his all-home-made station ties and St Ninian fields were also able to operate on 144MHz. which runs 600W input Beacon and repeater print-outs The Ghent group is to be congratulated on thinking up a Although information about beacons and repeaters is often novel way of stimulating random meteor scatter activity and at included in the pages of Radio Communication, vhf operators the same time encouraging operators to use the calling frequen- should realize that from the time it goes to press it can become cies correctly. ON5FF attended the RSGB National VHF Con- out of date. The only way to keep absolutely up to date is to vention, and his ms activity contest met with the unanimous order print-outs from RSGB Publications (Sales). The print- support of the ms operators attending the event. outs contain literally thousands of pieces of information about beacons and repeaters. All the data arc updated on a twice- 50MHz news weekly basis with sometimes 100 different pieces of informa- The west to east path from America to Europe has faded, and tion being changed in a one-month period. An idea of the detail American signals are not expected to reappear on 50MHz until in the print-outs can be gained from the fact that the beacon list the autumn. In response to many queries from stations who shows all the IARU Region 1 beacons in order of frequency, were able to hear signals from WB2RLK/VE I on 50MHz but giving their callsigns, latitude and longitude, QTH locator, erp, were unable to reply on 28MHz, the Canadian station was run- antenna and beam direction, height asl, keying mode and ning I kW to an 11-el Yagi antenna 17m above ground level. beacon keeper. Keen beacon and repeater users will want to Because of their ideal locations it will be interesting to see order new print-outs about every two months. whether El2W will be the first to work WB2RLK /VE I in the next transatlantic 50MHz opening. New IARU QTH Locator Map of Europe The path on 50MHz has now changed direction to N-S, and The new IARU QTH Locator Map of Europe is now available British operators G3C0J, G3FXB, G3BA and G4CBW have from RSGB Publications (Sales). The map has been extended all been copying signals from South African beacons, and some in coverage to meet the demands of the growing numbers of crossband contacts have been made with the UK operators vhf operators who are now able to work over distances which transmitting around 28.335MHz. ZS6ASO, ZS6AUB, ZS6XJ were not included on previous maps. The new map measures and ZS6BGQ were all good signals in the UK—the fact that 610 by 555mm and is ideal for mounting on the shack wall. ZS6BGQ was running 75W to a long wire is an indication of Alistair Simpson, GM8NCM, was one of many vhf operators the excellent conditions to South Africa on 50MHz. who bought the new map at the RSGB National VHF Conven- Garry Howarth, ZS6ASO, has sent details of the ZS 50MHz tion—only Alistair bought two. He intends marking off the beacons. ZS6ASO is the custodian for ZS6VHF which operates squares worked on 144MHz and 432M Hz on separate maps. on 50.040MHz and runs 50W to a four-over-four Yagi The map will be of particular interest to those operators who antenna. Z.S6VHF has been copied all over Europe in the last started chasing the new RSGB QTH Locator Squares Award few weeks, and can be copied for days on end by HB9QQ and which is valid for vhf contacts completed after 1 January 1979. SVIAB. Beacons are also operated from the homes of ZS6PW, The new map costs £1.15, and that includes post and packing in on 50.025MHz, and ZS6LM, on 50.045MHz. ZS6ASO also a tube to ensure safe delivery. sends news that ZS5C has been active on 50MHz and has had contacts with SV1AB and 5B4WR. ZS6XJ, at Randburg in the Transvaal, is now active on 50MHz ssb and rtty. All the First four band eme amateur African stations advise that they are listening on 28.335MHz Michael Owen. W9IP, has written from the University of for crossband contacts. Illinois, mentioning the visit he made to RSGB headquarters in John Price, G3UHH, is one of many stations re-equipping 1978 and his plans to establish a station for moonbounce for 50MHz; he can remember being a listener on the old 5m operation on 144MHz. W91P is assembling an antenna system band. G3UH H requests 4-2-70 to print a list of all the 50MHz with eight F9Fr Tonna 16-el Yagis and home-made power beacons, and the following should be added to the ZS beacon dividers. W9IP also sends in details of the first amateur

438 RADIO COMMUNICATION May 1979 equipped for moonbounce on four vhf bands; WB6NMT in "Spector" data system on 144MHz California has now had eme contacts on 50, 144, 220 and Peter Martinez. G3PLX, of Gosport, Hampshire. has been 432MHz, and all the QS0s were with normal amateur home- experimenting with an ruy system known as "Spector". The based (as distinct from large professional dish) stations. system is extensively used by professionals for ship-to-shore WB6NMT's antenna installation includes eight 10-el Yagis on telex traffic, and G3PLX and G3YYD have now set up an 144MHz, and an array of eight "tandem reflector" type amateur system on 144MHz using microprocessors to operate K2RIW Yagis for 432MHz. their rtty stations. The Spector system is very effective, as both stations work with very quick break-in, and errors due to Schedules wanted fading, etc, merely cause a repetition of the missing characters Claus Neie, DL7QY, the editor of the well-known European and a slight slowing down of the rate of copy. Spector has Dubus magazine, and avid vhf dxer, has moved QTH from transformed the 200k-m between G3PLX and G3YYD from a Berlin to southern Germany. The new QTH is 550m asl. has a "sorry, look for you when conditions are better" to a "hello, clear take-off in all directions, and is located in square FJ61e. what shall we talk about today" path. G3PLX feels that Spec- All the antennas are now in position, and DL7QY would tor is a very good system for vhf amateurs, and is especially welcome schedules on any band between 144MHz and 10 GHz. useful when conditions are poor or when signals are subject to Contact Claus Neie. D-7181, Rudolfsberg 24, Western Ger- fading. He assures other vhf operators that, despite the com- many. plexity, it is not difficult to get going with cheap home computers. (It is hoped to publish an article by G3PLX on Spector in the August issue—Ed.) British Amateur Television Club Contacts which were only 50 per cent copy with a conven- From time to time -enquiries arc received from members tional system can be transformed into 98 per cent copy, and requesting details of the British Amateur Television Club. The other QS0s which have been as poor as one per cent have been club publishes a quarterly magazine, CQ-TV, which covers all changed to 37 per cent. G3PLX feels this is not quite good aspects of amateur television including slow and fast scan enough for meteor scatter, but the principles could be used for systems. The club also organizes contests—the latest issue of a special ms system. On the subject of high-speed cw, G3PLX's CQ-TV gave the results of the most recent event, and the experiments showed the human ear was much better than the winner, G8DTQ, had 17 television contacts on the 432MHz mpu device. The mpu did perform much better with frequency band, the best dx worked being Fl BJB at a distance of 225km. shift keying and rtty, but he thinks the critical nature of the Membership enquiries should be sent with an sae to Brian receiver tuning would rule out fsk for ms contacts. G3PLX Summers, G8FQS, 13 Church Street, Gainsborough, Lincs. feels it is going off at a tangent to use a machine to encode/decode a code system designed for human use, and that Computer corner it would be better to use a system specially suited for a The item under this heading in the March issue sparked a large machine. He points out that he is not referring to Murray rtty reaction from readers of 4-2-70, with 32 letters being received code, which was designed for a mechanical decoder, but in the first 10 days following publication. Many letters referred perhaps to a cross between coherent morse and Murray code to the "Xitex cw, rtty, and ASCII to vdu." This unit has not without the start and stop bits. G3PLX has no direct yet arrived at the GM8FFX QTH, but the specification experience of meteor scatter, but would like to correspond with describes the display as being made up of 64 characters in a an ms enthusiast to explore the possible link-up of ms and 16-line format of 5 x 8 dot matrix. The 128-character set is full rnpus. upper case and lower case alpha, numeric, Greek, and some common symbols, with some special graphics provided by the on-board character generator rom. Many readers have en- Experiments by G4DGU quired about the cursor controls, and these include, up, down, Since obtaining an experimental high-power licence, Chris Bar- left, right, home, screen clear, carriage return, erase to end of tram, G4DGU, at Abingdon, has been spending a great deal of line or page, and direct cursor addressing, both relative and ab- time exploring the possibility of meteor scatter propagation on solute. Further details when the decoder is to hand. the 432MHz band. Previous attempts at ms contacts on Trevor Tugwell, G8KMV, secretary of the Stevenage RS, has 432MHz have been rather limited. and G4DGU is not aware of recently purchased a Pet computer and he has already pro- any professional observations of bi-static ms propagation grammed it for transmission and reception of rtty. He remarks above 400MHz. on the growing interest in computers among vhf amateurs, with Research into amateur literature reveals details of only two the Nascom 1 being particularly popular in the Stevenage area, authenticated contacts. The most recent took place between and he has eight computerized rtty stations within fm range of SK6AB and SM2AID, who managed a 432MHz ms contact his home station. G8KMV is surprised by the present Home over a 1,033km path during the Perseids shower in August Office ruling that 08 stations cannot contact each other on 1977. The only other QSO also took place in the same Perseids computer generated and received cw, and he takes the view that shower, but five years earlier, when WOLER and W2AZL set a there is basically no difference between sending or receiving world terrestrial record on 432MHz by completing the first ms either rtty or cw via a computer. Trevor considers the interna- contact on 432MHz. Many other stations have also tried, some tional morse code is merely a code like Baudot or ASCII, used with promising results. W7FJ copied a 27s burst from to transfer data from one station to another, and it is not WODRL, and Johnny Stace, G3CCH, copied bursts from TF; necessary to be able to receive Baudot or ASCII by ear at however, most schedules yielded perhaps a single ping in a 6h 12wpm before stations are allowed to use these other codes. test. Your scribe wonders whether the day is far off when one can G4DGU's interest in 432MHz ms was awakened after hear- bring not only one's own key for the cw test but also one's own ing a couple of pings from SK6AB during the big tropospheric computer! lifts in 1975. While waiting for the duct system to make its way

RADIO COMMUNICATION May 1979 439 into central England, G4DGU listened to stations to the cam and OZ ... Radio auroras are recorded as reaching the working SK6AB, and noticed he could hear signals which were following longitudes: 29 October, 49; 30 October, 51; 31 Oc- obviously via ms from Sweden. In 1977 a series of 432MHz 6h tober, 53; 2, 4 and 10 November, 61; 26 November, 53; but far- ms schedules were arranged during the Perseids with Karl thest of all was 25 November which reached 48 longitude. Mohin, SM3AKW, who is located in QTH square IW30e. UA4NM worked SM5BEI at a distance of 1,700km during the Unfortunately equipment problems prevented these tests tak- 25 November aurora ... UD6DFV, DGU, DIO and ing place, which was a disappointment for both operators, but UL7AAF, are reported to be active below 144.200MHz. particularly for SM3AKW who was critical of certain stations Meteor scatter 1978 review-U W6MA reports incomplete who had given up on the long schedules in the first hour. With contacts with D.I6CA, DL1BU and G3CCH, and he reports the arrival in 1978 of the special high-power licence, G4DGU hearing only LZ2FA, DL7QY, SM7 WT and and SM3AKW renewed schedules and ran tests during every HB9QQ . . . UQ2O W worked I4EAT on 6 August . . . Dur- useful shower. ing the Perseids, UA3LBO had completed contacts with Although no complete contact has yet taken place, positive F6EQQ and G3P01. results have been obtained and it is felt that with the availability of the higher power a full QSO should take place during future tests. It is obvious, with only two completed contacts Expeditions The Ghent Activity Group, mentioned earlier, is planning an recorded. that 432MHz ms is such a marginal propagation expedition to the Isles of Scilly to coincide with the August mode that it is of little use for most amateur communication. Perseids shower and the ms competition. It is planned to use G4DGU and SM3AKW are challenging the near impossible, two separate transmitters simultaneously; different callsigns but there is always the prospect of obtaining some unique will of course be used. By carefully synchronizing the transmit propagation data for a field apparently not well understood by periods on both transmissions, the group hopes to work much professionals. more dx. Ian White, G3SEK, also hopes to be in sync with the The 432MHz band lies in the arca of the frequency spectrum above transmissions during his expedition to QTH square where the relatively well understood mechanisms of vhf ms XJ-otherwise there could be much QRM in the south-west propagation arc believed to break down, or at least become during the ins contest. modified. G4DGU's experiments suggest that 432MHz ms The dates have still to be finalized for an expedition to operators can expect very few long bursts at this frequency. Andorra by Geoff Brown, GJ8ORH. Operation will probably Most of the signals heard were just pings, many with con- be on 144 and 432MHz. GJ3XQM will also be going to the siderable doppler component. This effect is usually attributed mountains in Andorra, and cw schedules will therefore be to the moving head of the meteor trail. As the size of the reflec- possible. Further details from GJ8ORH, QTHR. ting area is relatively small, the specularity requirement Another expedition of interest to the QTH locator hunters postulated at vhf begins to become relaxed. However, the will be that of GI4GTY, the Lagan Valley ARS, which is going received power is a function of the wavelength raised to the to the north-west of Donegal in the summer to activate the VP power of six according to an article by W4LTU published in square. A possible combined expedition from the six GI coun- QST May 1974. ties is also being planned for July by the Lagan Valley Group Thus these 432MHz pings are usually very weak, and the and the Mid-Ulster RSGB Group. News of the latest dx expedi- presence of doppler shift makes them very difficult to copy. tions will be carried on the GB2RS news bulletin. Although the requirement for specular reflectivity from the trail begins to be relaxed, it is still advantageous to ensure that the schedule times coincide with the optimum path geometry. To this end, Dr Geoff Grayer of the Propagation Studies Com- Auroral reports mittee was persuaded to write a computer program enabling There has been a distinct lull in auroral activity during the first the optimum times and, more importantly, beam headings to three months of the year. Radio auroras took place on the following dates: 2, 3, 4, 5, 6, 7, 15, 16, 20, 21, 22, 23 and 30 be calculated. The use of this data has contributed greatly to January; I, 4, 16, 21, 23, 26, 27 and 28 February; 6, 10, 22 and the partial success of G4DGU and SM3AKW, who exchanged signals, but still not enough for a QS°, during the recent 25 March. The aurora on 10 March was first heard by Pete Quadrantids-the first ms signals ever heard during this Bates, GM4BYF, in Edinburgh, at 2320gmt, when the only signal to be heard on the beacon band was DLOPR. Twenty- shower. Further tests continue. five minutes later, the German beacon was a strong signal but it peaked up on a north-west beam heading. Cornish beacon GB3CTC could also be heard at S4 on this unusual heading, VHF news from Russia but by 2350gmt the aurorally reflected signals changed to a Radio Communication's equivalent in Russia is a magazine more normal beam heading of 30°. Lerwick beacon GB3LER called Radio, and at times Radio has reprinted items from could then be heard for the first time that evening at S9, but 4-2-70. It was therefore a pleasure to receive in the mail from this opening only lasted for a few minutes. After completing a Roy Stevens, G2BVN, an English translation of the recent vhf cw contact with El6AS in Dublin, the opening faded away in pages in Radio which are edited by the well-known Estonian the middle of a contact with a station in ZK square, possibly vhf operator UR2BU. Because this information has not been G4GBX. Auroral propagation must have been quite good for available before, extracts are printed below in "Grapevine" those few minutes, as 4-1-70 has since been informed that style. GM4BYF was also called by G3VJR, in South Yorkshire, and 1978 auroral openings review-RA3XBS in Obninsk worked by G3P.IX in Dorking, Surrey. 12 countries on 1 and 2 May . . . UR2RD from Island The event on 22 March was the best of that month, but it was of Saaremaa in Estonia had 36 contacts during 4 June an afternoon-only opening in mid-week when activity was not aurora ... UQ21V worked SM5BEI, SM5KX and OH3SE on 14 June . . . On 13 August UQ21V and UQ2O W worked OH Continued on page 446

440 RADIO COMMUNICATION May 1979 amateur service situation is quite unlike that of the commercial interests. Amateurs have some I 5 non-allocated simplex chan- VHF/UHF band planning nels between 145-20 and 145-575MHz, and quite an extensive all-mode sector between 144•5 and I44•85MHz for non- by TOM DOUGLAS, G3BA, VHF Committee channelized operation. With such a wide spectrum of frequencies for fm users to occupy, one would find it very difficult to chairman, and IAN WHITE, G3SEK, vhf manager sec the immediate necessity to increase the number of available channels. Even in areas of high amateur population density, Why use RO? the number of channels noticeably occupied seldom reaches The recent introduction of the GB3CF repeater on channel RO double figures at its maximum, and more usually is around the has caused a great deal of controversy, for the input frequency five or six mark. On the repeater side, eight channels, RO-R7, of 145-000MHz is widely used for simplex traffic in the UK. are currently available and with careful planning these channels Since it is quite possible that other repeaters in the future may should give more than adequate mobile-mobile contacts in any also need to use RO, readers may be interested to know why given area without co-channel interference for more than 95 that is necessary. per cent of the time. When the foundations of the 144-146MHz band plan were The extra channels obtainable by changing to a 12-5kHz spac- laid in 1972 there was no RO, only RI -R9. But by 1974 the ing would be bought at the expense of several technical prob- countries in which repeaters developed more rapidly than in the lems. First is the very important question of oscillator stability. UK were finding the need for another channel, so RO became Even with 25kHz spacing, the average competitively-priced part of the European band plan, and S20 was designated the fm transceiver available on the present-day market is far from calling channel. At that time the RSGB view was that no more being really stable under the exacting conditions met with, par- than eight repeater channels would be needed in the UK ticularly under mobile operation in a vehicle where extremes of (R1-R8), and that simplex on 145.0MHz could co-exist with temperature often cause the transmitted frequency to be as the use of that frequency on the Continent as the input for much as 3kHz off, plus the equivalent in receiver mistuning. repeaters on channel RO. The situation with narrower channel spacing would be that Much has changed since 1974. The vhf world has widened: much more difficult to contain, and almost certainly would increased activity and better equipment have brought UK vhf need much more sophisticated methods of frequency control amateurs into much more frequent contact with the Continent, than at present employed. All this would inevitably mean an and hopes of co-existence between simplex and repeater traffic increase in the cost of the equipment. on 145.0MHz have proved unfounded. Under good propaga- Also, to adopt 12.5kHz channel spacing would entail a nar- tion conditions UK fixed stations operating simplex are a con- rower i.f. filter system being employed. On 25kHz equipment siderable nuisance to repeaters in France, Belgium, Holland this would mean changing the existing filter, resulting in fur- and Germany, as their strong signals over-ride those of the ther cost for purchase and fitting. To mix 12.5 with 25kHz local low-powered and poorly-sited repeater users. If equipment is also not really practical, as there would be a 145.0MHz were also being used in the UK by mobile stations requirement on the 25kHz operators to drop their peak devia- working through repeaters on RO, there would be far fewer tion to around-..t.-2-5kHz, and that would be a most unpopular problems. move. Another major change since 1974 is that the UK vhf repeater A 12-5kHz receiver would lose out on signal to noise, par- system has expanded rapidly, and in the last few years has ticularly in the presence of impulsive noise QRM. Interference caught up with the rest of Europe. As foreseen in 1974, eight from a non-co-operative wide-deviation operator would be channels are still required, but R8 is no longer available since unbearable and cause bad feeling all round. What with lower the amateur satellite service needs a wider allocation at the hf deviation and poorer noise reduction, weak signal reception end of the band; hence RO must be used. would be noticeably worse were 12.5kHz standards to be A question often asked is: Why not put GB3CF on RI or adopted. R2? The answer becomes clear to anyone who cares to plot Taking all the disadvantages into account, there seems little repeater sites and channels on a relief map, as did the VHF point in changing to a 12-5kHz spacing until the fullest possi- Committee's Repeater Working Group. Seven channels are ble use has been made of the existing 25kHz channels with the just not enough to avoid frequent interference between present aid of modern synthesized equipment. However, when the time or planned repeaters, so use must be made of RO. does come eventually, to make the change, it will be to Since there is a well-used calling channel on S20 and plenty 12.5kHz, and it is right that fm users should know this well in of simplex working channels, why not leave 145 •OHMz for use advance. as a repeater input? A.M. calling frequency 12.5kHz fm channel spacing Although many people imagine that a.m. is a thing of the past, Recent advertisements for 144MHz fm transceivers have this is not so, and there are still many adherents to that very asserted that 12•5kHz spacing of channels is here; or is com- excellent mode, particularly among those new to the vhf scene. ing; or that the world would end if it did! Now that the once-popular a.m. frequency of 145.80MHz is It is, of course, technically possible to split up the recom- no longer available to operators because of satellite service mended fm allocations into channels of 12-5kHz width, and requirements, there is a strong feeling that there should be a this has already been done for the UK land mobile services; but nominated a.m. calling frequency around which those wishing amateur service needs are quite different from those of the to use this mode may congregate. The VHF Committee has commercial user services. The main reason for the adoption of given this some thought recently and suggests 144.550MHz as 12.5kHz spacing commercially was to increase the number of a possible frequency which would be compatible for synthesiz- channels in order to accommodate more users and provide less ed equipment and for simple vxos. Reactions to this proposal countrywide interference from adjacent transmissions. The from the a.m. fraternity would be welcomed by G3BA.

RADIO COMMUNICATION May 1979 441 West Coast DX Bulletin mentions a report that Dr Selim El- • Rafai, 0E6EEG, has been exploring the possibilities of a visit the month to Abu Ail, in the Red Sea. Late April or May is the time mentioned, and it is said that three operators may take part. Permission has been given for some activity from Franz on the air Josef Land, and this may still not have taken place by the time this reaches readers. All bands 1.8 to 28MHz, and both cw and ssb, will be used during an around-the-clock operation. It is John Allowoy, G3FKM * believed that the callsign will be RI FJ. ZL I ADI and ZL1AMO are planning a visit to Manihiki Is to follow their stay on Pitcairn Is. This should last two weeks and take place during May. Their callsign will probably be ZK I HI. The Wiesbaden ARC will visit Liechtenstein between 26 May -KT 0 apologies are offered for bringing up the matter of QSL cards yet again. GM4BDJ has received a QSL from and 3 June. Their callsign will be DA1 WA/HBO and they will the USA which does not indicate a signal strength report, and use all bands from 3-5 to 432MHz. Their frequencies will be (cw) 25kHz from lower band edge, and (ssb) 3,780, 7,090, while this may be perfectly acceptable for DXCC it is not 14,280, 21,350 and 28,650kHz. QSLs should go via DJOLC. satisfactory for the majority of award applications. QSLs should always carry the following information as a minimum requirement: (1) the callsign of the station worked, (2) the date of the contact, (3) the time of the contact, (4) the mode and Top band signal report—and (5), perhaps rather obvious, the confirma- Fernando-Juan Fernandez, EA8CR, who is a vice-president of tion that a contact has in fact taken place! Your scribe has seen URE, has written to say that Spanish amateurs now have per- cards on which this has not been mentioned and which were in- mission to use 1.8MHz. He has had special permission to do valid for transmitting awards. A very important point to be this for some years, but the privilege is now extended to EA, remembered is that any alteration whatsoever renders a card EA6 and EA9, although there are some restrictions due to the useless for DXCC credit and that anyone submitting an altered presence of other users of the band. Activity is expected to be QSL runs a grave risk of being disqualified from the club. found mostly during contest weekends. More photographs are urgently needed for MOTA —glossy black and white prints being best for good reproduction. Every effort will be made to return pictures (if this is requested) but DX news no full guarantee can be given. Ken Whithorn, G3BDS, is receiving QSL cards for "3V8BA" who seems to have been using his callsign as QSL manager. W2PV 3V8BA appears to be a pirate and it is not possible for Ken to Many readers will have heard the incredible signals which reach answer any QSL requests. Likewise, 3V8HA is unknown to the UK from this famous USA station. Dr Dain Evans, G3RPE W2RA. (who would normally consider the frequencies reviewed in SP5GH wishes it to be known that he is not acting as QSL MOTA to be intermediate frequencies), has passed on details manager for the station HV5GH. He knows nothing about of the antenna farm at W2PV which he has received from such a station and will not answer any correspondence concern- K1ZZ. It seems that there are three masts: (a) 180ft fixed, (b) ing contacts with it. 150ft fixed, and (c) 112ft rotatable. Mast (a) supports a Amar, VU2CZ, secretary of the Amateur Radio Society of 1.8MHz inverted-V, a 2-el 3.5MHz quad, stacked 3-el 7MHz India, reports that the society was formed on 14 May 1954 and beams—the upper is rotatable but the lower is fixed on Europe, that this year is its silver jubilee. To celebrate the occasion the and four 4-el 28MHz fixed beams. Mast (b) carries a 7-el society's station will operate under the special callsign I4MHz beam, stacked 5-el 14MHz beams fixed on Europe, VU25ARS during the month of May. and stacked 4-el 2IMHz beams fixed on S America. Mast (c) Those who still need a QSL card from FY7AK or FYOBHI has on it a 3-el 7MHz beam, and stacked 6-el 14M Hz, stacked should send a direct application to Richard, F2QQ, who has 8-el 21MHz, and stacked 10-el 28MHz beams. Further com- just received a fresh supply from the printer—see "QTH ment seems superfluous! Corner". A station using the callsign 4W2AA has been heard near Dxpeditions 14,340kHz around 2000 and asking for QSLs via 12M VS. It has Lloyd and Iris Colvin made 12,000 contacts from Honduras been suggested that this is 12Y0 who visits Yemen occasion- using their HROQL call, and worked 129 countries. This was ally. The signals from STORK should be greatly improved, as he the second most successful of all their expeditions, only being should by now have received a new beam. exceeded by the 14,000 QS0s they made from VP2MAQ a few DF6SL will be DF6SL/KC6 for about one year. He is years ago. Normally, visiting amateurs are required to use their located at Truk in the E Caroline Is, and tends to be found on own callsigns with a /HR suffix; however, the official respon- Wednesdays between 1200 and 1500 on 14,220kHz, and also on sible for issuing the licence remembered Danny Weil and man- Thursdays from 0600 to 0900 on the same frequency. aged to issue a special event radio call—HROQL. Contrary to T2T has been very active from Tuvalu. His operating the information given in last month's MOTA, Iris and Lloyd schedule has been given as follows: 0430 to 0730-7,003kHz; did not return to the USA from Honduras, but moved on to 1000 to I I30-21,025kHz; 1800 to I900-21,355kHz; and 2100 Belize where they were active as VP I KG. to 2200-28,503kHz. W5RBO is often involved in forming a "list" on the last-mentioned frequency. ZD9GH is often to be found in the 1900 to 2100 period • 10 Knightlow Road. Birmingham B I 7 8QB. around 14,230, 14,250, 14,270 or 21,320kHz.

442 RADIO COMMUNICATION May 1979 Some of the Tartan Net at the first-ever meeting: (standing) GM4GJG, GM4GGF, GM4HJG, GM4DOX, GM8HXM, GM4FIB and GM8NGL; (sitting) GM4HFE, GM3HMU, GM4FIW. GM4DKO and GIVI4DCL

OK3TAB/D2A claims to be in Angola and to be called Caci. The Tartan Net He is said to be found from 1900 on 14,275kHz, from 2200 on The power of amateur radio to bring together enthusiasts of all 14,200-14,205kHz (looking in this case for USA and Canadian callings and persuasions was demonstrated at the first-ever contacts), and also occasionally on 21,265 and 28,600kHz. meeting of the Tartan Net in an Edinburgh Hotel on 12 QSLs should be sent via OK3ALE. January this year. Nicaraguan amateurs are now using special prefixes, and What started two years earlier (to the day) as a natter-net on YN I H was signing as H7H during the WPX Contest. He was 28MHz for two or three of Leith Nautical College's RAE also expected to do this on 1 May, and again on 14 and 15 "graduates" of '76 has become a regular Sunday evening QSO September and 12 October; H6H and HTOH may also be used. with up to a dozen south-east Scotland GM calls and some The Scout Association reports that an Australian Rover regular visitors from across the pond—mostly expatriate Scots. Leader, Adrian Blake, is with the Australian Antarctic Expedi- The 28MHz band lends itself to this kind of mixture of local tion at Mawson, Antarctica, and will be there throughout 1979. and dx work, and the Tartan Net seems likely to continue to His callsign is VKOAB and he expects to be on the air at 0930 thrive. on Tuesdays, Thursdays and Sundays, and possibly other days One of the net's founders, GM4FIW, who pulls in the dx for too. His frequency will be around 14,150kHz, and he will be the net, arranged this get-together and enabled members of the looking particularly for Scout contacts. net to put faces to callsigns for the first but, evidently, not the S2BTF says that he is likely to be found on 14,205, 14,225 or last time. 14,285kHz between 1730 and 1900, or on 14,051kHz after Next "eyeball" in VE land perhaps? 1900. Father Moran, 9N IMM, keeps a schedule on 28,625 kHz at 1400 on Tuesdays, and on Thursdays at 0200. He also uses 14,225kHz from 0000 and 14,245kHz from 0100. Contests West Coast DX Bulletin reproduces a report that HB9APN The USSR "M" Contest has been on the air from the Swiss embassy in Peking using the 2100 12 May to 2100 13 May. callsign HB9APN/A/BY from 1400 on 21,I55kHz. This activi- Phone and cw, 3-5 to 28MHz. Whole world may be worked, ty is said to be likely to continue until 20 May. The "BY" suf- not just USSR. The same station may be worked on each band, fix seems to lend some doubt to the validity of the station. but only on one mode on each. Exchanges consist of RS/T plus ZS6BEE is the replacement who is going to Marion Is serial QSO number, Soviet stations will also give their oblast (ZS2MI) to take the place of ZS1TD. number. Contacts with stations in one's own continent count one point, and with those in other continents three points. QRP Contacts with own country count only for multiplier credit. Results of the 1979 QRP Winter Contest organized by the The multiplier is the total number of countries on the AGCW-DL Group have been received via G4BUE. In the Class "R-150-S" list worked on each band added together (this list is A section (input less than 3 -5W) G4BUE led with 18,423 similar to the DXCC list but also includes seven UAO areas as points. He was followed by OK IDKW (4,656) G8PG (3,094), separate countries—Dickson Is, Magadan, Taimir, Tuya, GM30XX/A (2,346), DJ6FP (2,334) and G3DNF (2,221). Chukotsk, Yakut and Sakhalin. It also includes all VP2s as one Other UK scores were G3NE0 (767), G4GIE (502), G4EJN country, as KC6, KG6 and KX6 are, and also KB6, KJ6, KM6, (204) and G4AYS (106). KP6 and KW6). Final score is total points multiplied by total During the Commonwealth Contest G4BUE worked VE2FU multipliers. Listeners may enter and should claim one point for and VE3IXE, running an input of only 15m W to his Argonaut! reporting one station exchange and three for both—there is no During the ARRL CW DX Contest W3M M, K8NZ, and K1ZZ multiplier in this section. Licensed amateurs may enter the were contacted with 10m W—the actual power output being single-operator single- or multi-band, or multi-operator multi- confirmed later as being only 5761/W. All these contacts were band section. A special badge will be sent to all who contact 10 made on 28MHz cw. or more USSR stations. Post logs before I July to: Krenkel Please note that the operating frequency of the G-QRP Club Central Radio Club, "CQ M" Contest Committee, PO Box 88, is now 3,560kHz. Moscow.

RADIO COMMUNICATION May 1979 443 QTH CORNER The Diploma Altamira Contest FWBAD via W70K. W. D. Brickey, Box 95, Las Vegas. Nev. 89101. 0001 9 June to 2359 10 June. USA. Organized by the Santander group of URE to mark the FY7AK via F200, R. Gemehl, 25 rue Mauriceau, 92600 Asnieres, FYOBHI France. centenary of the discovery of the famous prehistoric caverns in H7H PO Box 2616, Managua, Nicaragua. the area. All bands 3-5 to 28M Hz, ssb and cw—contact may be VK2VGV/VK9 Box 214, Norfolk Is, 2899, Australia. VP1KG via YASME Foundation. PO Box 2025, Castro Valley, Calif, made with a station on each band, but only on one mode, on 96546, USA. each day; further contacts may be made on the second day. Ex- VCI9RL 1126-A 34th Street, Port Hueneme, Calif, 93043, USA. VR6HI C. Rademacher, ZL1ADI, Box 41066, St Lukes, Auckland 3, change RS/T and time. Santander stations will use the EAO New Zealand. prefix. Each ccintact with an EAO will count one point on ssb or VS5M via N4GG, H. F. Kennedy, 275 Tollgate Trail, Longwood, Fla, 32750, USA. two on cw, and with EAOURE two and three points respec- YJBKC via ZL1BAB. W. G. Cooper, 41-A Kelvin Rd. Papakura. New tively. Logs should list date, time, station worked, number Zeeland. received and sent, band, mode, and points, and QSLs should YJBPD via VK30T, S. R. Gregory. Box 414, Hamilton. 3300. Vic. Australia. be enclosed "a QSL per band worked with each EAO station". ZB2EN via R. S. Wilkinson, G3JXE, 55 Summergangs Drive, Thorn- gumbald. Hull. They should be posted before 10 July to: Diploma Altamira 302WR via G5RP, E. Wake, College Farm Hse, W Hencired, Wantage. Contest, PO Box 1, Santillana del Mar (Santander), Spain. The Berks OX12 BRP. 4U1UN H. Bohning, VV2MZV, Box 102. Yonkers, New York, NY, 10702. winner of the contest will be invited to spend a week in San- USA. tillana del Mar at the end of September at the time of the KIYT/5T5 via DJ4PI, E. Neuerer, Doemigweg 6, 7505 Ettingen, W Ger- many. special festivities. 9H31MAR via 9H1R, R. V. Meachen, 1 Jasmin Path, St Lucia, Malta. 9N1B MK via JA8BMK, H. Sasaki. Box 150, Asahigawa, Hokkaido, 070-91, Japan. Awards RSGB QSL Bureau, G3DRN, 30 Bodnant Gardens, The R-10-R London SW20 OUD For contacting all USSR regions (0 to 9) during a 24h period since 1 July 1958. The R-6-K For 12 contacts—one each with Europe, Africa, North and South America, Asia, Oceania, plus three with European Note that contest contacts may be credited for Russian Russia and three with Asiatic Russia. Starting date 7 May 1962. awards in lieu of QSL cards if the request is made with the log It is in three classes: First (for all 3 .5MHz contacts), Second entry. This applies to the R-150-S, R-100-0, W-100-U, R-15-R, (for all 7MHz contacts) and Third Class (any bands). R-10-R and R-6-K awards. The R-150-S The CQ WPX Contest (CW section) Contacts with 150 countries of the world, including the 15 0000 26 May to 2400 27 May. republics of the USSR since I June 1956. Rules are the same as those for the ssb section which was held The R-15-R in March; and will be found on page 248 of the March issue of For contacts with all 15 republics of the USSR within a 24h Radio Communication. Please note that G3FKM is now only period on cw or phone (not mixed). Starting date 1 July 1958. able to supply summary sheets and one photocopied log form The R-100-0 as guidance. For contacts with 100 oblasts (all cw or all phone) since I January 1957. Three classes as with R-6-K. lOth World Telecommunication Day Contest A list of QSL cards (certified by the awards manager of a 0000 to 2400 12 May (Phone). national society) plus 14 ircs should be sent to Box 88, 0000 to 2400 19 May (CW). Moscow, USSR. Note that contacts in the "M" Contest (see 3.5 to 28MHz. Single-operator multi-band and club and "Contests") may be claimed for credit for these awards in lieu association special multi-operator sections. Exchanges consist of QSL cards if application is made with the contest entry log. of RS/T plus ITU zone number (UK is in Zone 27). Contacts with stations in own country count only as a zone multiplier, The Sasqualch Award with another country in the same zone as one point, with one in For five contacts with amateurs in the Chilliwack district of another ITU zone on the same continent three points, and with VE7—two of whom must be members of the Chilliwack ARC others five points. The final multiplier is the number of dif- (VE7s AFA, AHN, A10, AKD, AND, BEN, BHG, BYU, ferent zones worked—each counting once only. Stations may BZY, EWO, EX, FK, NHF, PU, QN, RS, TL and ZI). Others be worked on each band for credit. Logs should indicate date, in the area include VE7s AGZ, AYZ, BBV, BDH, BIF, BIB, time, station worked, numbers sent and received, band, conti- BPW, CBQ, CTO, CTW, CIX, CQO and GM. All must have nent. ITU zone (if new multiplier) and points claimed. Separate been made since I March 1979. Send copy of log and three ires logs should be completed for each section. G3FKM has a small to CARC, c/o 317 Marshall Avenue, Chilliwack, BC, V2P 3J5, number of summary sheets. Logs must be posted to LABRE Canada. UIT Contest Co-ordination, PO Box 07-0004 70.000— Congratulations to BRS339I 5 on being one of the 49 successful Brasilia, DF, Brazil, to arrive before 30 August. The applicants for the Canterbury Aero Club 50th Anniversary ITU Trophy will be awarded to the country with the highest ag- Award (see MOTA July 1978). gregate of points earned by entrants. The top scorer in each country will receive a certificate. The Diploma Altamira In the 1978 event G4CVZ, GW3SLA and GM5AXY scored This is being awarded to participants in the contest of the same 5,120, 2,656 and 150 points respectively, and in the phone sec- name (see "Contests") and will be given to European . tion G3TXF (14,625), G3MZV (12,475), G2AJB (8,517) G6NK applicants who score 30 points, those in N and S America (2,761) and G6GH (1,596 points) were listed. require 20, and all others 10. It will be sent via the national

444 RADIO COMMUNICATION May 1979 society, except to those who enclose five ircs for direct postage. Propagation predictions

Summer conditions prevail in the ionosphere in May. Day-time frequen- Fiji Association of Radio Amateurs cies are noticeably lower in the northern hemisphere compared with Upali Ranasinghe, 3D2UP, has announced that the Fijian winter, and this will be most pronounced on 28M Hz in traffic with North society, FARA, has been restarted with the following office America. The conditions of certain traffic during the winter months become fewer and will only extend to a few hours in the after- bearers: president-R. L. Northcott, 3D2CM; joint noon under very favourable conditions. This worsening of conditions secretaries-Upali Ranasinghe, 3D2UP, and Bernard MaIan- will not be as pronounced in traffic with Africa and South America, dain, 3D2BM; treasurer and QSL manager-Raj Singh, because the F2 mufs do not show any noticeable reductions in 3D2ER; and committee members-George Williams and Bob equatorial regions in the summer. In contrast, the night-time frequencies will be higher than in winter, Hodkinson, 3D2BH. The society's address (which also applies and this will lead to considerable improvement of dx conditions on to the QSL bureau) is: FARA, PO Box 184, Suva, Fiji. 14MHz during the night. Short skip conditions usually start in May, and they will quite suddenly facilitate contacts within Europe on 28 and 21MHz with good results, but these conditions will be very sporadic. Welcome Changes of dx conditions on 21MHz will be less severe, with traffic with eastern North America being possible on favourable days during the The following overseas amateurs joined the RSGB during afternoon and evening, although it will most probably be best in the February: A9XCE, DK1KR, DK6AJ, El6BT, El 7DG, F2W W, evening. G8EKB/W1, ISOESS, K3JLF, K8YAH, ON4TX, ON6WS, The start of winter in the southern hemisphere will influence, above OZ4JV, PAOBUD, SM3DPO, SM5KI, VE3AMJ, VE7TL, all, traffic with South Africa, with a break in traffic between 0200 and 0700. Absorption is usually too high on this path during the middle of VK2AE, VK6WC, W91YG, ZL2AMP, ZR5CG, ZR5DH, the day. On 14MHz dx will first be possible with Asia and Australia in ZS1DP, ZS6KF, 5B4AH and 6Y5HB. the afternoon, and later with North. Central and South America as well. Traffic will be possible all through the night until just after sunrise. With Australia, traffic will be possible during the afternoon and first half of the Jamboree-on -the-air night via the eastern path, and during the time to sunrise via the western path. DX will be possible on 7M Hz. mainly when the whole path lies in The report of the 1978 event has just been received and it in- darkness, but static and ORM will interrupt traffic. During the day dicates that this was the most successful held so far. There were 7MHz will be best suited to local OSOs. Signals will be stronger, 397 stations active in the UK-including nearly 100 with special especially at mid-day, than on 3-5MHz, although 3-5MHz will provide GB callsigns. A record of 658 overseas Scout stations in 59 good local traffic, and there will be no interruption by the dead zone in the second half of the night. different countries appeared on the bands-slightly fewer The provisional sunspot number from the Swiss Federal Observatory countries than in 1972 when 64 were heard. It seems that, par- for February 19'79 was 138. The highest daily number of 171 was record- ticularly in the USA, activities spilled over into the 27MHz ed on 21 February. The daily mean number for 1978 is 92-5. The predicted smoothed numbers for June, July and August are 159, citizens' band and where it is legal for Scouts to speak to each other. 162 and 163 respectively. The 1979 JOTA will take place over the weekend of 20-21 Oc- tober. Readers may like to note that world Scout frequencies The editor regrets that, due to staff illness, the usual "Propagation are as follows: (cw) 3,590, 7,030, 14,070, 21,140 and predictions" diagram cannot appear in this issue. 28,190kHz and (phone) 3,740, 3,940, 7,090, 14,290, 21,360 and 28,990kHz. Scout nets are held every Saturday in the UK at 0800 on 3,740kHz. Other nets are listed as follows: (European) 0930 Saturday on 14,290kHz; (Scandinavian) 0830 on the first Interesting and unusual contacts are being made on Sunday of every month on 7,090kHz; (Australian) 2300 on the 28MHz-G3MBA sent a recording of one with a mobile station fourth Sunday in every month on 14,120kHz; (Norwegian) (AX6NDZ) on the Indian Pacific express in W Australia. 1430 every Saturday on 3,740kHz, and (Danish) at 1030 every G3LEQ reports a number of contacts with USA stations using Saturday on 3,740kHz. fm, and also mobile ssb QS0s from his car-these including one with WA2KSW/AM who was flying a military aircraft at Band reports 35,000ft, and another with VK4NJC/M who was driving a G8KG's summary for the past month is as follows: The Zurich truck at the time, power output in every case was only 12W. sunspot data for March were not available at the time of The following kindly provided logs from which this section writing but preliminary reports suggest that on many days the was compiled: Gs 2AMV, 2HKU, G3s AAE, GVV, KSH, number was well above 200, so that the monthly mean may well LEQ, LPS, SED, MBA, XBY, GM3LYY, GM4CH X, G4s turn out to be in the region of 200. If this is so, then Cycle 21 is BUE, EAN, EHQ, ETN, FMO, G5JL, G6GH, G8KG, BRSs catching up on Cycle 19. On the other hand the daily solar flux 17567, 25429, 31301 and 33915. levels were somewhat lower than in February, with the seven- Stations listed in italics were using cw, the rest ssb. day mean lying between 180 and 190 sfu for most of the month. 1-8MHz. 0100 HI8JAG. 0300 KP40. 2200 DKEAS/LX. 2300 ED5HM, If the pattern of January and February is repeated there should ED5NY. 3-5MHz. 0500 KP4AM/D. 0600 ZL. 0700 ZF1CF. be a significant rise in mean solar flux during April. 7MHz. 0200 YN1Z. 0300 C5AAP, VES- VEZ 9.1280. 0500 XE1A0, The general effects of the increasing solar activity on the VR6H1. 0600 CM, EL, FP8F0, K9VCM/HR1, M1C, VE6-VE7, ZL. 2300 higher bands were very much in evidence during March. On VK6s GU, HD, VP9IR, VU2Ra 28MHz there were morning openings lasting several hours to 14MHz. 0400 VR3AH. 0600 VREHL 0700 CEOAE, F08, VR6HI. 0800 FB8YI, FW8AD, KAIIW, KC6GF, VK9RH, VKOPK (Macquarie Is), ZL 1 /ZL2 and the western Pacific islands, and on a few morn- VR3AH, 5W1AX. 0900 FK8CR, VR3AH, WH4AAA, 3D2MD. 1000 ings there were early long-path openings to eastern Australia. KP4AM/D. 1500 YI1BGD. 1600 UOCR (New Siberian Is). VQ9RL. 1700 The onset of summer conditions was signalled by the A7XAH, FH80M, S8AAP, 601FG. 1800 FW8AD, JT1AN, KH2AD, KH6, KL7, TAISU, VS500. VR1BD. 1900 A7XA, OK3TAB/D2A, appearance of good long-path openings to JA, VK and ZL in FK8CR, FR7ZL /T, KC6GF, VS5M, 8Q7AH. 2000 VR1BD. 2100 the evenings on 21MHz, and there was at least one similar W7ZGA/KH2, VP2MBU (OSL to WA4ZSX), VP8S0, 9N1BM. 2200 opening to eastern VK on 28MHz at 2200. UA1ABL/UAO (Severaya Zemlya), VP8s QG, SO.

RADIO COMMUNICATION May 1979 445 21MHz. 0000 JK1DVX/JD1, 9N18HG. 0700 KL7MF. 0800 9L1CA. 0900 JA, UOCR, VK, ZL. 1000 AX6NDZ/rail mobile. 1600 KP4AM/D. 4-2-70 1700 OK3TAB/D2A, 5N2AIF (QSL to DJOVT), K4Y7/5T5. 1900 WA1S- QB/HC8, KA1NC, 5W1AX, 9L1CA (QSL to WA3NCP). 2000 4U1UN. Continued from page 440 2100 HH2A, KC4AAD, VP1KG, ZD8KG (QSL to K4KBI). 2300 VK6, W6, ZL. 28MHz. 0300 VK3YT. 0500 UG6. 0600 JA, UJ, UL, VK, ZL. 0700 A35RB, HL9KE, JA, VE6PN, VQ9MR, VU. 0800 A6XJA, FK8CK, HM1EJ, H44s PT, JD, KH6, STORK, VR3AH, ZL. 0900 H44s PT, WH, JE1IVI/JD1, UAO, 9H79CG. 1000 H44JD. 1100 CR9AJ, D4CBS, KG6SW, KL7, VK8, ZL. 1200 OK3TAB/D2A, FK8CW, HZ/HZ (Ahmed, at a high level. Alex Dunn. GM8DMZ, at Patna in Ayrshire, Box 1999, Jeddah), K1CO/PJ7, G4IDW/SU, SU1DP, VIQVGV/VK9, first noticed the aurora at 1330gmt, and he reports that the K4Y7/5T5. 1300 AP2UR, 0E2WSL/YK, ZL3UM. 1400 JY1, P29NDU. aurora was farther to the south than usual and that it peaked 1600 WA1QSB/HC8, KL7HHX, VP1KG. 1600 FGODYM/FS7, HS1ABD, VCISJJ, VRO. 1700 CE, FYOEOL, VP8HA, ZD7SD, ZF2CL. 1800 J6LGK, on a beam heading of 50°. GM8DMZ worked all the QTH VR6H1. 1900 FGODYM/FS7, HH2T, KH6, KL7, KP4AM/D, VP1KG, squares in Holland and had many ssb contacts with stations in VO9JJ, 2K1DR, 6D1LCH. 2000 KH6, KL7, VE7, VY1BR, W7, ZL1DH, Germany and Denmark. G8ODN near Carlisle also used ssb to ZURE, 6.14RCA. 2100 CE, HP, VK3, VP2SK, VR3AR, ZD8. 2200 contact 12 stations, including a very strong signal from G8LYD CR9AJ, FK8CW (QSL to KaJW), FM7, JA, VK2BA, VK3, W6-W7, VP2MCU. 2300 JA1BRK, VK3, ZL2-3-4. 2400 ZL2PN. in Manchester, and from GW4HDF in South Wales. G8ODN also had some morse practice by copying the ac-sounding cw Many thanks to the editors of the following for news items extracted: the West Coast DX Bulletin (WA6AUD), DX'press signals from G3UQH, in Shrewsbury, and El5BH in Co Athlone. (PAOTO), CQ Magazine (W1WY), the Ex-G Radio Club Bill Duckett, G8BKF, in Shropshire, first noticed the aurora Magazine (W3HQ0), DX News Sheet (Geoff Watts), and at 1550gmt, and he worked several Scottish stations on ssb. Best Long Skip (VE3FRA). Please see that all information for July issue reaches G3FKM dx for G8BKF was GM8A0B in Fort William, Invernessshire, a station mentioned as an outstanding signal in several reports. by 2 June, and for August by 28 June. Note that August Martin Wheeler, GM8RHH, in the Hebrides, using a TS700 deadline is abnormally early! and a 9-el Tonna antenna, was getting pile-ups of stations anxious to work WS square. GM8RHH reports G4HDQ and G8JHL as the strongest signals via the aurora. GM4COK in Edinburgh came home early on the afternoon of 22 March as he knew there was a possibility of a repeat following the event of 23 February. Keeping his solar rotation calendar certainly HF propagation study paid off for GM4COK, as he worked 30 stations, including G3FPK, LA6Z W(ET), PAOCSL(C M), F2JQ(DL), DL9AR(FM), DF6VO(GM). and, best of all, DM2DTN(GK) Predicted hpfs (MHz x 10) for May 1979 GMT= 00 02 04 06 ce 18 20 22 24 and DM2BYE in HM square. GM4COK beamed at 70° for Men 266 258 296 346361 373 392 394 385 351 318 293 266 most of the above contacts, and the aurora faded out with him Ascension 312 296 288 241366 368 402 428 421 399 356 317 312 Battrais 243 239293322343 345 359 359 366 336 299 268 243 following a contact with DB1BP at 1639gmt. Bangkok 227 219 270 290296 2% 335 318 321 299 270 241 227 Another aurora on 25 March hovered around for most of the Barbados 2% 256 233 237281 296 339 319 323 336 336 312 289 Bermuda 268 229 204 205232 266 284 295 296 321 303 268 afternoon and evening, with auroral signals on 50MHz from 781 242 218 218270 285 298 313 319 327 335 309 281 130901a Scandinavian television stations being very strong at times. Buenos Aires 300 276 262 224173 296 355 368 371 371 351 317 2% Cape Town 279 199 150 346368 390 415 431 423 399 351 303 279 SK4MPI and GB3LER did eventually show up on 144MHz at Colombo 238 3% 294 318321 332 345 346 355 324 288 257 238 Cyprus 229 721 249 296313 321 337 332 341 317 222 258 229 2330gmt, but signals were weak in Aberdeen, and although it Dakar 312 296 288 246366 36s 402 428 421 399 356 317 312 showed early signs on 50MHz this aurora failed to develop into Denver 215 196 181 164171 172 210 223 242 242 242 248 215 Fairbanks 192 173 173 199221 205 204 192 199 1% 199 199 192 a large-scale event. Falklands 197 183 169 153210 272 3/28 392 383 384 352 290 197 Gibraltar 180 167 161 180210 215 233 232 230 232 218 199 180 Hong Kong 219 219 257 266284 281 291 293 304 290 261 224 219 Honolulu 192 173 173 199223 230 243 219 247 241 235 218 192 Iceland 153 139 140 164182 182 194 192 195 199 204 177 153 Late news Jamaica 2139 233 209 208244 270 284 295 298 310 318 301 268 Lagos 313 293 288 321365 379 415 430 422 404 354 314 313 Further auroras occurred on 29, 30 March, 2, 3 April. The Las Palmas 266 247 232 225295 310 333 332 333 335 313 281 266 event on 29 March was the strongest, with 0Y5NS being work- Urna 291 266 241 246 243 321 341 338 346 341 313 291 Los Angeles 199 190 178 183169 164 196 239 247 248 253 235 199 ed by many 144MHz stations. SM1BSA, in JR square, was Malta 1% 189 185 239251 263 2ao 272 272 268 246 226 199 Mauritius 280 220 290 356368 379 398 408 398 332 301 260 another outstanding signal, being worked by GM3UU and Mexico 246 218 191 195235 218 266 272 277 284 296 277 246 other Scottish stations; G8DVK, G8KSS and G8LYD were the Montreal 239 209 188 169195 225 244 248 260 2E6 272 271 Moscow 189 176 206 225239 242 247 249 257 249 229 211 188 strongest G signals at Aberdeen. On 70MHz GM3YOR used Neitobi 270 277 289 355368 385 403 420 404 368 318 296 270 the same event to work G3UKV (YM28), G4ENA (ZL08), New Delhi 230 219 277 299307 312 314 323 322 301 274 242 2% New York 246 218 191 172194 235 247 253 265 271 294 284 24$ G3FDW (ZN56) and G3OSS (ZL49); GM3YOR reports most Osaka 208 206 232 247252 260 2% 267 280 260 244 219 2C8 Perth 237 228 294 315321 328 338 314 261 242 204 186 237 signals were 5 9a on the lower band. Rio de Janeiro 301 239 276 248210 343 393 392 383 384 352 317 301 On 20 March SVIAB and SV1DH copied signals from ZE2- Salisbury 303 265 241 359368 390 416 420 411 387 345 307 303 Seychelles 279 265 294 346368 379 398 396 397 347 321 294 279 JV's 432MHz beacon for 15min; signals were auroral sounding Singapore 3% 219 277 299307 312 314 324 332 303 274 242 230 and are the longest (6,300km) ever reported via te on 432MHz. Suva la) 192 176 199 223229 235 247 247 247 247 235 218 192 Suva II) 313 295 288 »8300 276 310 218 196 187 3E8 315 313 Signals from ZS6LN were heard in Cyprus on 144MHz by Sydney (s) 219 219 257 266284 281 277 257 229 197 196 224 219 5B4AZ on 23 March. G3C0J had further crossband 50MHz Sydney 291 266 241 265276 235 204 211 191 1139 289 312 291 Teheran 238 229 294 318321 332 338 346 355 323 285 2E6 238 contacts with ZS at the end of March. SMIRK No 1, K5ZMS, Vancouver 192 173 173 197196 196 191 199 216 216 246 223 192 Wellington (s) 202 202 221 241248 260 255 219 1% 190 248 216 202 worked ZL IAVZ on 10 March at 2105gmt; this was his first ZL Wellington 301 289 2132 268251 215 181 182 159 187 336 319 :901 in 20 years of activity on 50MHz. SV I DH plans a IkW beacon

Bands recommended are those between hpf and half hpf. on 432M Hz. Full details on all these items next month. CI

446 RADIO COMMUNICATION May 1979 worldwide. The Ottawa S-figure measures solar radio emissions at Solar and propagation informa- 2,800MHz, the frequency which most closely approximates to the size of the visual sun. A lower frequency would, in effect, view a larger sun; a higher one would see a smaller sun; and a very high frequency, ie X-rays, tion in GB2RS news bulletins would see only spots. Therefore 2.800MHz is the most appropriate frequency. At the bottom of the solar cycle daily S-readings are below 70; at times of moderate activity they rise to 100-130, while at periods of intense by C. E. NE WTO N, G2FKZ * activity they can exceed 200. Anything over 150 is considered high, and in the absence of any information to the contrary can be taken osa pointer to good hf propagation. EVERY Sunday the RSGB news bulletin broadcast over GB2RS These solar radio noise figures have been adopted as one of the basic contains information about solar and geophysical events which indices for predicting values of fol and foFI up to six months either have affected, or may affect, radio propagation, together with ahead —which are the basis of propagation predictions published in Radio forecasts of likely conditions, and this brief guide will help listeners to use Communication. Monthly means of solar flux are given as they become this information to best advantage. The bulletin's factual data usually available, although these are adjusted to tau (1 astronomical unit). This relate to the week up to the Tuesday preceding the broadcast, and are as assumes that the earth is the same distance from the sun at all times, and up-to-date as possible bearing in mind the time necessary for data centres therefore the attenuation of the 2,800MHz signal due to distance is con- to obtain, collate and despatch them. Use is also made of the Meudon, stant. They are designated Sa. France, ursigram radio transmissions of solar data, the Wednesday The highest possible frequency I lOper cent reliability) figures published ursigram of Tuesday's data being the latest that can be included. in Radio Communication are updated when some degree of confidence Forecasts normally run from the Sunday of transmission to the following can be expected; this is, of course, a forecast, and is given as an upgraded Sunday. reliability percentage for the following week. The basis of this upgrading is the current solar flux and A indices against the units used for the original Solar activity prediction. However, the success of these ventures depends on the feed- Solar information may refer to rotation numbers, each 27-day rotation back hf operators giveto the forecaster. This is a service of the RSGB Pro- having a Carrington rotation number. Interesting activity centres (such as pagation Studies Committee carried out by the author, who would major sunspot groups, flares, coronal holes, etc) can be referred to in appreciate comments, suggestions—or brickbats. latitude north or south and heliographic longitude, which gives both position on the solar disc and date of central meridian passage. (Frequently Geomagnetic information the radio effects of solar events are experienced around the timeof central Every three hours the geomagnetic field is measured in three dimensions: meridian passage, although this is not always the case.) horizontal (h), declination Id) and vertical (z). That showing the greatest A solar rotation base map for up to one year ahead, using Carrington variation at any time is used for computing the three-hourly K index. rotations and heliographic longitude (as used in the bulletin) is available Sometimes the bulletin will refer directly to this K index, but more often it from RSGB HQ. With this map, a solar calendar can be kept and central will express magnetic activity in terms of the 24-hour A index. The A scale meridian dates recorded. is, in fact, derived from the K data, but where K is compressed into a 0-9 Solar activity refers to background flares and sunspots, mostly small in logarithmic scale, the scale is linear and more extended and this allows size and short in lifetime. This activity varies, depending on the number of variations to be shown in rather finer detail. active regions and the type of flare emissions that occur in the optical. Where a bulletin refers to quiet conditions this means that, over the X-ray, and radio spectrums in general. The effects are classified as: period 0900-2359, A variations did not exceed 10 units. "Unsettled" Solar quiet: No active regions erupting. indicates variations of 10-20 units. -Sub-storm" or "minor storm" means Solar moderate: Active regions erupting but of low intensity. an A reading of 20-50. "Storm conditions" means 50-80. "Severe storm" Solar active: One or more active regions erupting, with high inten • means 100-200 or even more. (These values are in terms of mid-latitude sity bursts, or new active regions forming, or both. stations —at an auroral station like College, Alaska, peaks may be as high Large flares can have an almost instant effect on the ionosphere. as 400. As far as possible the bulletin uses European mid-latitude data, but regardless of their position on the solar disc, whereas auroral effects nor- where these are not available it may quote data from Fredericksburg, mally occur 30 to 50 hours after the event, and usually, but not always, Virginia, a mid-latitude observatory comparable to Lerwick). after central meridian passage of the event. At various times reference is made to special events which either have Large sunspots of an area in excess of 500 millionths of the visual disc occurred or are expected, such as: are sometimes notified to the RSGB; they are given as date first Coronal holes. These are areas in the solar corona where helium 10830 A seen — this depends on the weather at Hurstmonceux. Date on disc gives (Angstrom units) has been detected by the Kit Peak Observatory, USA. the total passage time from appearing over the east limb to its disap- There appears to be a strong association between the presence of weak pearance over the west limb. Date of disappearance, central meridian auroras and coronal holes. In practice it is only the more northern stations passage is given as day and fraction of day. eg 7.3. The Zurich relative which can actively participate in this type of event, so they have tended to mean sunspot numbers are given as soon as they are available —about be called Scottish-type auroras. An A index of up to 35 or 40 can result two months in arrear. Zurich smoothed numbers are not usually given as from the passage of coronal holes past the sun's central meridian, they are at least six months in arrear. especially if it is near the solar equator. Proton events. These are detected by satellites if the energy level is in Solar flares excess of 10MeV (mega electron volts). They are given in the bulletin as a These are divided into three types, C, M and X. C-type flares are very com• guide to whether active regions on the solar disc are intensifying or are mon and are of low intensity, about 80 to 100 per week are normal at the expected to continue active, as proton particles cause high absorption in present time. In effect, they give the general background to the solar flux. the D region and so affect the lower hf bands. They are also responsible M-type flares are of greater intensity than C-type and can cause earth for polar cap absorption events which affect communication over the events such as magnetic storms (usually minor) and short-wave fade-outs poles. (swf I of varying amounts. These are sub-classified M1 to, say, M4. The Solar filaments. These are tenuous streams of flare-type gas which resulting magstorms of M3 -M4 flares usually give Scottish-type weak often protrude from the solar surface. It sometimes happens that one of auroral events. SWF is given in hours or minutes of extent, if known. these in a very active region will disintegrate very rapidly with considerable X-type flares are violent, big and accompanied by X.ray type emissions. consequences on earth. A disintegrating solar filament was responsible They usually cause widespread blackouts of the hf spectrum, but there for the wide-scale visual and radio aurora of 28 August 1978. It was 0.8 of does not appear to beany definite association between auroral eventsand a solar diameter long, and all but the stump suddenly disintegrated. These X-type flares. They are detected by satellites up to X8; in excess of that it is events are unpredictable, violent and sudden. In the UK the A index can necessary to deduce; such as the event of 11 July 1978 which reached X15 reach 100 plus with this type of event. (the largest known) although it produced no aurora. Interpretation of solar and geomagnetic data is undertaken in the Unless of special interest, optical flares are not normally reported in the bulletin, but, in general terms, an A index of 25 or more may produce bulletin. auroral conditions over northern Europe and Scotland. However, for auroral working from the south-east at least 45 is required, or about 60 if 2.800MHz solar flux values moderately powered stations are to participate; 90+ is required for The measurement quoted in the bulletin is made daily at the NRC Radio auroral working to be widespread throughout Europe. Observatory near Ottawa, Canada, at local noon (170Dgmt), and is valid In hf terms the ideal combination will be a relatively high S reading and a low A reading. For instance, excellent hf conditions were encountered on 5-6 November 1978 when the solar flux was 184 and the A index was *61 Merriman Road, London SE3 8SB minimal.

RADIO CO M MUNICA TIO N May 1979 447 at exhibitions. If members have any ideas they would like to put before the committee please write to G8NM W or any other member of the ragnet committee. G8NM W will be particularly interested in any practical ideas members may have on promoting the Raynet image with the general public. Last, but not least, please do not forget the RSGB National Amateur • Radio Exhibition at Alexandra Palace on 11 and 12 May. The usual sup- R. Bullard, G8N M W* plies, including new Raynet ties, will be on sale there. Hope to see you there on the RSGB stand.

Home Office regulations Under an agreement reached in March 1979 with the Home Office Radio Regulatory Division, Raynet members may, under conditions of operational oil pollution incidents, at the direct request of a county emergency planning officer or member of his staff, embark with them in craft to RSGB com mittees, 1979 provide a communications link to the shore within a two-mile seaward limit. Note: This permission cannot be used for exercise purposes and is for (The President is an ex-officio member of all committees) LIVE OPERATIONAL OIL POLLUTION EMERGENCIES ONLY. All instances where Raynet members have been called upon shall be reported to the emergency communications manager as soon as poss- Education: D. H. Adams, GW3VBP; J. Anthony, G3K0F; R. Bellerby, ible afterwards. G3ZYE; G. L. Benbow, G3HB; L. E. Newnham, G6NZ; G. C. Oxley, Members are advised to ensure that life jackets or buoyancy aids are G8M W; D. M. Pratt, G3KEP; W. A. Scarr, G2WS; F. C. Ward, G2CVV. available in sufficient numbers before embarking in any small craft. Finance Er Staff: E. J. Allaway, G3FKM; P. F. D. Cornish, G3COR: D. S. Evans, G3RPE; B. O'Brien, G2AMV; C. H. Parsons, GW8NP: R. F. Raynet membership Stevens, G2BVN; C. J. Thomas, G3PSM. Referring to Clause 4C, page 14, of the Raynet Manual, it shall be HF: E. J. Allaway, G3FKM; R. J. Eckersley, G4FTJ; S. H. Jesson, deemed that membership commences from the time that the prospec- G4CNY; J. D. Kay, G3AAE: D. J. Lawley, G4BUO; F. M. Smith, tive member receives his/her Raynet membership card from his/her G8KG*; C. J. Thomas, G3PSM'. controller. Persons under the age of 14 years are not eligible for Raynet HF Contests: E. J. Allaway, G3FKM; D. J. Andrews, G3MXJ; D. S. membership. Booty, G3KKQ; R. L. Glaisher, G6LX; M. Harrington, RS20249; C. A. P. Henderson, G4FA M; P. A. Miles, G3KDB; E. L. Mollart. RS10977'; D. Thom, G3NKS: R. S. Unsworth, G3wpF_ National Raynet Com mittee The following is a who's who of the committee, together with their job IARU: E. J. Allaway, G3FKM; D. J. Andrews, G3MXJ: D. S. Evans, G3RPE; R. J. Hughes, G3GVV: R. F. Stevens, G2BVN; R. M. Warner, description(s): Chariman— M. G. Barker, G8CAC. Responsible to Council and the com- G3SAR; I. F. White, G3SEK. mittee to chair committee meetings. Interference: S. R. Allen, G4CYR; J. Anthony, G3KQF; P. F. Jobson, G3HLF; A. S. Kessler, G4DXA*; Miss J. Maggs; J. E. Martin, GU3YIZ'; Vice chairman— E. W. Yeomanson, G3IIR. Responsible to the chairman and committee to arrange meetings and act for the chairman in his K. H. Parker, G8HTA; J. E. Swayne, G3BLE•; J. W. Swinnerton, G2YS; C. L. Turner, G3VTT. absence. Emergency com munications manager—P. Balestrini, G3BPT. Council Membership Et Representation: D. H. Adams, GW3VBP; E. J. appointment, Responsible to council and committee for liaison between Allaway, G3FKM; D. J. Andrews, G3MXJ; J. Anthony, G3KOF; L. N. Home Office, RSGB and committee, as defined by Council. G. Hawkyard, G5HD; G. I. Knight, GM8FFX; W. F. McGonigle, GI3GX1); B. O'Brien. G2A MV; C. H. Parsons, GW8NP. Correspondence secretary—L. A. Crane, G3PED. Responsible to chairman and committee for dealing with the day-to-day correspondence Microwave: B. Chambers, G8AGN; D. S. Evans, G3RPE; H. Griffiths, G4CNV: D. T. Hayter, G3JH M; K. S. Hutchinson, G4ALN: H. W. Rees, sent to Raynet. He is the main link with ordinary members. All queries, G3H WR; K. L. Smith, G3JIX; C. W. Suckling, G3WDG; M. H. Walters, etc should be sent to him. Items requiring a more specialized answer will be forwarded to the appropriate committee member. He deals with all G3JVL; I. F. White, G3SEK. group controller and organizer nominations and changes. Mobile Et Exhibition: P. Balestrini, G3BPT; L. N. G. Hawkyard, G5HD; R, S. Hewes, G3TDR; W. J. McClintock, G3VPK; N. Miller, G3MVV; G. Minuting secretary—E. R. L. Bassett, BRS16075. Responsible to chair- W. Norris, G310; D. P. S. Wright, G4FB W; E. W. Yeomanson, G311R•. man and committee for production and distribution of the minutes of Propagation Studies: L. W. Barclay, G3HTF; B. Chambers, G8AGN; each meeting. T. Damboldt, DJ5DT•; W. M. Dune'', G3BY W; D. S. Evans, G3RPE; R. Group information officer—T. I. Lundegard, G3GJ W. Responsible to chairman and committee for all group records and information on G. Flavell, G3LTP: G. H. Grayer, G3NACC; R. A. Ham, RS15744*; M. Harrison, G3USF•; R. J. Hughes, G3GVV; C. E. Newton, G2FKZ; A. M. groups, their officers and operating frequencies, the user services they Pomfret, G3LZZ*; J. Spurling, G4A01; G. M. C. Stone, G3FZL; A. serve, and the area each group covers. He circulates each group zmnu- ally with a questionnaire to ensure the records held are up to date and Taylor, G3DME; R. C. Whelan, G3PJT•. correct. Raynet: P. Balestrini, G3BPT; Mrs P. Balestrini; M. G. Barker, G8CAC; E. R. L. Bassett, RS16075: R. J. Bullard, G8NM W; L. A. Crane, G3PED; Publicity officer— R. J. Bullard, G8NM W. Responsible to chairman and committee for all publicity distributed by the committee to HQ and/or G. B. Lear, GW2HPG*; T. 1, Lundegard, G3G../W: D. J. Maud, G8MBB; the news media. Responsible for exhibitions, displays etc. All items of S. J. Scarborough, G3MBO*; E. W. Yeornanson, G3IIR, publicity should be sent to him by groups. Technical Et Publications: R. J. Eckersley, G4FTJ; D. S. Evans, Supplies officer —Mrs J. Balestrini. Responsible to chairman and com- G3RPE; T. G. Giles, G4CDY; P. J. Hart, G3SJX; J. P. Hawker, G3VA; R. S. Hewes, G3TDR; P. A. Holliday, G3UVZ; P. J. Horwood, G3FRB; mittee for the supply of Raynet items and stationery, etc, to the groups. A. W. Hutchinson, editor; J. W. Mathews. G6LL•; M. H. McFadden, Ordinary committee members —G. Cluer, G4AVV; B. L. Goddard, G4FRG; J. Maud, G8MBB; G. Lear, GW2HPG (corresponding); J. Scar- GI3VCI*; R. O. Phillips, G8CXJ; H. W. Rees, G3H WR; R. F. Stevens, borough, G3MBO (corresponding). Responsible to chairman and com- G2BVN. Telecom munications Liaison: E. J. Allaway, G3FKM; P.Balestrini, mittee for the general advancement of Raynet both at local level in their G3BPT; S. A. G. Cook, G5XB; T. P. Douglas, G3BA; D. S. Evans, own areas and also at national level. G3RPE; R. J. Hughes, G3GVV; D. M. Pratt, G3KEP; R. W. Price, Mrs T. Crane acts as registration secretary on behalf of the committee for the recording of membership registrations and maintains registration G4BSO*; R. F. Stevens, G2BVN; C. J. Thomas, G3PSM: F. C. Ward. G2CVV. records. VHF: M. S. Appleby, G3ZNU; A. H. B. Bower. G3C0J; A. H. Dormer, With the above information to hand it should now be easier for G3DAH; T. P. Douglas, G3BA; G. I. Knight, GMBFFX"; R. W. L. members to write to the com mittee when needing information, giving information, or with a cry for help, knowing that it can be directed to the Limebear, G3R WL*; C. J. Morcom, G3VEH•; G. M. C. Stone, G3FZL; R. J. Taylor, G4BEL: I. F. White, G3SEK; E. W. Yeomanson, G3IIR•, right quarter. G8NM W will be more than happy to receive any items of news that members may care to send to him, and he will endeavour to VHF Contests: L. N. G. Hawkyard; G5HD; F. Mathews, G8ACJ; W. J. McClintock, G3VPK; J. H. Quarmby, G3XDY; C. Sharpe, G2HIF; G. M. publicise them through GB2RS. GB2_ATG, RSGB newsletters and C. Stone, G3FZL; C. W. Suckling, G3WDG; R. J. Taylor, G4BEL: L. V. publications and, of course, through the public news media, as well as G. Turner, G4CUT.

•12 Moriston Road, North Brickhill, Bedford. ' Corresponding member.

RA DIO CO M MUNICATION May 1979 OUT OF THE MOUTHS... The Editor e your opinion Radio Communication Sir-1 have recently had the chance of browsing through various issues of Radio Communication from over the past 10 years, and 1 have become increasingly aware of the constantly recurring arguments by which our hobby has been beset over that time. These have included ssb y a.m. y fm y cw, Class A y Class B, homebrew v. commercial, band BAND PLANS.. AGAIN plans, repeaters, and so on and so on. I am beginning to think that The Editor people would rather talk about than participate in this hobby. Surely one Radio Communication of the great things about it is that there is so much scope for doing one's Sir —I would like to add further comment on the subject of the use and own thing without the sort of petty niggling at everyone else which has misuse of S20, with regard to the 144MHz band plan. Since moving to been going on? One fact which cannot be stressed too much is that this is Lincoln a little while ago, I have noticed that a small group of amateurs the year of VVARC. We should all be trying to make the fullest use of our persists in using S20 for their ''rag chews". Most of them are Class A allocations and frequencies, sensibly and enthusiastically. A good im- licence holders and, from the antiquity of their callsigns, can be termed pression can be made at any time, but no time is as important as now, so "old-timers" or, as some would have it, "real amateurs". This is at the please stop the grumbling. least a petty irritation, and at worst can cause real problems, as on Something else to be borne in mind is that newcomers hear ALL Thursday 15 February. operating habits, and copy accordingly. Absolute newcomers might even At the height of the snow storms, with roads fast becoming blocked be completely put off by what they hear, and the younger or more im- and telephones going out of action; there was the same little group pressionable may accept everything without question. Even the worst sitting rag chewing on S20 for three hours. Sitting snug in their shacks habits seem to produce results, but the real dx chasers are a patient discussing how many feet of snow were piling up against the garden gate, careful majority, and in the long run far more successful. Please, keep while mobiles were calling, in vain, for assistance, without being heard. I your good operating habits, and throw out the bad ones which can be actually intercepted a distress call from a mobile on S21, after he had detrimental to both you and your hobby. called in desperation for half-an-hour on S20. The same group later The only thing that I have to add is that I am just 16, and have, I hope, claimed, very self-congratulatory, to have "kept S20 open" for many years left in this hobby. There are many other young people in a emergency use! similar position. Your present actions are their future, so please help to The following day, when road conditions were extremely hazardous make that future rosy. and most telephones were out of action, a mobile at the scene of an R. M. Mackean, G4HAO accident was unable to summon help because the same group was on 520. They do not seem to realize how far their 10W signals from WINDING POWER TRANSFOR MERS omnidirectional antennas radiate beyond the station which they are The Editor working. I have tried gentle persuasion and reasoned argument without Radio Communication success; so, on behalf of the rest of the stations in the Lincoln area, I Sir —Referring to the article "Power transformers with low voltage apologize to the mobiles who have passed through our area and called secondaries" in your February issue, I feel the paragraph on "Turns per CO on S20 without making contact. volt" may be misleading. If we could hear you, we would work you. When the original primary winding is being left untouched, the "turns Prenda Peters, G8MON per volt" has already been established for a particular transformer by the The Editor manufacturer when he calculated the number of primary turns necessary Radio Communication for the mains power supply voltage involved. Sir —I was very pleased to see in the February issue of Radio To find this "turns per volt", wind on a temporary test winding of, Communication, in "The Month on the Air", the remarks about the use say, 10 turns after the original secondaries have been removed, and of telephony in the IARU band plan sector 3,500 to 3,600kHz recom- reassemble the core if this was removed. Then connect the primary to the mended for cw only. mains supply and measure carefully the voltage developed across this For a long time now, a group of amateurs, mostly with old-time calls, winding on open circuit. From this can be calculated the "turns per have been using telephony, mainly a.m., but with some ssb. and volt" and the number of turns necessary for a particular voltage secon- spreading, in some cases, very broadly. dary, but increasing this number by a few turns to allow for the voltage To approach within 10kHz of them is to incur complaints of deliberate drop that will occur under load. interference. This is no doubt due to the wide passband of their I have rewound a number of transformers on these lines with complete receivers, and it is no uncommon thing to find them 5 to 7kHz apart, success. quite under the impression that they are in fact netted. R. O. Rowntree, G3Z0A In the past, in my opinion, the RSGB has only paid lip-service to the hf band plan (which, it is realized, is voluntary) by printing it in the January issue of Radio Communication and then forgetting about it until next January. A little more publicity at frequent intervals would help, and some remarks on the RSGB news broadcasts occasionally would be welcome, to me and to many other members. I have written or spoken to some of the persons concerned, requesting A Guide to Amateur Radio their co-operation in observing the band plan, and in turn, I have been 417th (KIM accused of deliberate interference myself (I usually work cw at the top end of the 3.5MHz cw sector), previously with QRP, but after being often clobbered by this group I mainly use about 100W. Pat Hawker, G3VA I would point out that among the frequent members of this group is an RSGB area representative, and I think that if personally requested by the Provides the newcomer to amateur radio with basic information RSGB to co-operate in keeping to the band plan, a lot more attention on receivers, transmitters and antennas. This book also contains would be given to a letter from that source than to all the letters or technical information and operating data of interest to all radio moans front individuals. amateurs and listeners. Personally, I would welcome a band plan written into our licences, Chapter titles: This is amateur radio; Getting started; COM- and I think that the abandonment of the first year licence for cw and M uleication receivers; Transmitters; The antenna; Amateur radio CRP was a great mistake, the results of which are only too apparent equipment; Workshop practice; The licence examinations; now. Operating an amateur station; The RSGEI and the radio amateur; J. Douglas, G2CAS/ON4ZD International amateur radio organizations.

The Editor 120 pages: paperback. £1.71 incl p&p Radio Communication Sir— With the advent of synthesized rigs and channel-scanning equipment, surely there is now a case for the removal of the "calling channel" restriction from S20? Obtainable from This will enable those of us with limited financial resources to use all of our crystals for effective communications. RSGB Publications (Sales) G. A. Evans, G8DXY

RADIO COMMUNICATION May 1979 449 Logs were mostly very good, although two had to be completely re- scored. Most points were lost for incorrect resigns. ( contest news Subject to the approval of Council, the Somerset Trophy will be awarded to G3VM W. Certificates of merit go to GM3ZSP, G4BUO, DJ8WL, F9KP, DJOOE, PAOLOU, OK1D WF and OLf3CGS. Finally, thanks go to G3USE and G3ZRZ for their most useful check logs. G3WPF February 432M Hz Fixed Contest results UK SECTION This contest was run under poor conditions. The weather was wet and Posn CallsIgn Points Posn Cellsign Points miserable, and activity was judged low by some and good by others, 1 G3VM W 730 24 G3OGY 454 with more stations on in the south than in the north. However, par- 2 GM3ZSP 712 25 G2MJ 435 ticipants enjoyed the contest very much. G3VZV asks the question, 3 G4BUO 640 26 G4CZB 416 "Where do all the stations go after the contest?" 4 GM4ALK/A 625 27 G3UKC IG4CSCI 414 5 G3YMC/A 615 28 G3ILO 409 The rules were liked by all, unusually, there being no adverse com- 6 G4B WP 614 29 03FITI 408 ments. The single-operator, multi-operator division of entrants, as 7 G3SYN1 604 30 G4EBK 391 recommended by IARU Region 1, is therefore judged a success for this 8 G3SJJ /A 588 31 G3SNX 387 particular contest. 9 G4HMS IG3HZL I 585 32 G W3JI 374 Congratulations and certificates go to the winners of the two sec- io j- 013IVJ 573 33 G3LCH 371 tions. L G3XTJ 573 34 0 30K8 370 12 G3PDL 563 35 G4BOU 356 G3FZL 13 G3XTT 561 36 G3YEE 350 SINGLE-OPERATOR 14 G3NOM 533 37 G4AEM 341 Posn Callsign Points DSOs 0TH Best dx Km 15 G4CNY 519 313 G3TXF 267 1 G4BEL 707 123 AM51h GD2H02 370 16 G3SJE 514 39 G3FVVV 228 2 GD2HDZ 425 41 X068b G8AYN 440 17 G3GC 512 40 G3AHS 219 18 G3S WC 510 41 G3SVW/A 199 3 03100 416 100 AL51g GO2HDZ 430 4 G8LEF 362 56 ZN2Id PAOHVA 455 19 G3OLB 502 42 G3ULY 166 5 G3SPJ 293 74 AL41a G8AZA 310 20 G W3KOR 496 43 G4HSO 147 6 G8DKK 287 79 ZLO8d GO2HDZ 372 21 G13JEX 471 44 G3EGG 141 7 G8FMG 286 66 ZM78a GO2HDZ 350 22 G3KKO 459 45 0802 104 23 G3TKF 455 8 G4CCIR 278 77 2L450 GO2HOZ 440 9 G4FSG 276 45 AM77a PAOVVH 317 10 G3YTE 261 61 AL13b G2AMV 295 11 G3UBX 236 52 YM40g G3B W 240 OVERSEAS SECTION 12 G3VZV 232 60 ZLO8h G8BCL 218 13 G8AZA 208 28 2069h G3BH W 340 Posn Consign Points Posn Callsign Points 14 G6GN 206 44 YL48h G8PLR 275 1 DJB WL 451 6 OL8CGS 140 15 GW3U00 187 32 YN65c G4FSG 303 2 F9KP 392 7 DJ4K WA 97 16 G8LHT 170 34 ZN34c G3TDG 3 DJOOE 298 8 OK1AXD 70 17 G3TQF 167 41 ZM24d COORS 180 4 PAOLOU 241 9 OL9CJB 67 18 G4ASR 163 31 YM77g 038 W 275 5 OK1D WF 172 19 G4CGS 158 28 ZN11d G3GRS 337 20 08002 155 35 2M41g G3GRS 190 21 G5UM 152 48 ZM35b GD2HDZ 266 22 G813JG 132 54 AL411 G8LEF 275 21/28MHz Telephony Contest 1979 rules 23 G3IGO 123 49 ZL68h G3UNU 195 24 G3VJG 118 50 21_40g G3WOH 269 TRANS MITTING SECTION 25 G8KAX 107 43 AL32g GD2HOZ 425 Licensed amateurs and swls throughout the world are invited to take 26 G8CTT 97 97 AL41j GBLEF 280 part in the RSGB's 21/28MHz contest. Log and cover sheets may be 27 G3LCH 85 41 ZL50g G8LEF 298 28 GBDAB 79 37 ZL57a G3UNU 179 obtained from: RSGB, 35 Doughty Street, London WC1N 2AE. UK 29 G4H MF 77 19 AM76c G8LEF 263 members should enclose a large stamped, self-addressed envelope. 30 G3FIJ 64 22 AL05e G3UNU 185 The general rules for RSGB hf contests, published in the January 31 G3LVFM 61 35 ZL30g G3NNG 105 issue of Radio Com munication, will apply. 32 G4GGV 43 21 ZL37g G3UNU 157 1. Eligible entrants. British Isles: RSGB members only. 33 08115 42 27 ZL40e G3UNU 175 34 080X0 33 13 YM696 G4BEL 160 Rest of world: All licensed amateurs. 2. Period. 0700gmt to 1900gmt on 14 October 1979. 3. Section. Single-operator only. 4. Bands. 21MHz and 28MHz only. MULTI-OPERATOR Posn Callsign Points QS0s ORA Best dx Km 5. Exchange. RS plus serial number starting at 001. 1 G3NNG 549 107 ZL23I PAOVVH 514 6. Scoring. 2 G3UNU 544 102 ZMO4c GO2HDZ 255 la) British Isles stations for a contact with a station in the rest of the 3 G8OGL 458 104 ZL47i GD2HDZ 399 world will score three points. The RSGB countries list will apply with 4 G3XZW ,A 335 15 YL75c G4BEL 262 VE, VK, W/K/N /A, ZL and ZS call areas counting as countries for 5 G4GRS 297 73 AL52b G3WOH 309 this purpose. 6 G8KGH 265 51 YL48h 04F50 273 lb) Stations in the rest of the world for a contact with a station in the 7 040DY 256 76 SL6Oh GD2FICIZ 256 8 G8ADN1 148 44 ZL64a PE1AVVY 405 British Isles will score three points. British Isles stations may not work each other for points or multipliers, and stations in the rest of the world must only contact stations in the British Isles. First 1.8MHz Contest 1979 results 7. Multipliers. The total number of countries contacted on 21MHz The number of UK entries was one up on last year, but 10 up on the added to the total number of countries contacted on 28MHz, then Second Contest 1978. However, there was a considerable fall in the multiplied by the total of points scored on the two bands. number of overseas entrants -45 entries were received from the UK and Multipliers for the rest of the world stations will be the total number of nine from overseas. Disappointingly the only "under 18" entrant was different G prefixes worked on 21MHz added to the number of different OL8CGS. G prefixes worked on 28MHz, then multiplied by the total of points Conditions seem to have been variable. A number of stations worked scored on the two bands. K1 POW but activity from the Continent seemed low. The earlier starting British Isles prefixes are: 02, G3, 04, G5, G6, G8, GD2, GD3, GD4. and finishing times attracted a number of comments, mostly favourable. G05, GD6, GD8, 012, GI3, 014, 015, 016, GI8, GJ2, GJ3, GJ4, GJ5, There were plenty of stations still to be worked at the end, and the GJ6, GJ8, GM2, GM3, GM4, GM5, GM6, GM8, GU2, GU3, GU4, GU5, leading stations "missed out" on 20 to 30 contacts. GU6, GU8, GW2, GW3, GW4, GW5, GVV6 and GW8. Contacts with GB The winner and the runner-up each had 157 contacts, but G3VM W stations will not count for points or multipliers. had more bonus points. G4BUO had 132 contacts. Combined with his B. Logs. Log sheets to be headed: Date/gmt; station worked; RS and score in the Second Contest 1978, the score of GM4ALK/A earned him serial number sent; RS and serial number received; multiplier; points the Maitland Trophy. In the overseas section, DJ8 WL had 93 0.50s, claimed; separate logs are required for each band. Summary sheet while F9KP had 68. showing multipliers worked on each band must be submitted.

450 RADIO CO M M UNICA TION May 1979 9. Declaration. Each log must be accompanied by the following declaration: "I declare that my station was operated in accordance with Contests calendar the rules of the contest, and in accordance with the requirements of my amateur radio licence." The declaration must be signed and dated. 432 / 1,296/2,304MHz (Rules in March issue) 10. Address for logs. RSGB HF Contests Committee, c/o M. Har- 5 6 May Region Round-up CW (Rules in March issue) rington, 123 Clensham Lane, Sutton, Surrey SM1 2ND, England. 6 May World Telecommunication Day (Phone) (Rules 11. Closing date for logs. British Isles entrants should ensure their 12 May entry is received by 14 November 1979. Overseas entrants should submit in May issue) their entries to arrive not later than 3 December 1979. 12 13 May USSR "M" (Rules in May issue) 12. Awards. The Whitworth Trophy will be awarded to the leading 13 May DF Qualifying Event South Manchester (Rules in British Isles entrant overall, and the Powditch Trophy will be awarded to April issue) the leading British Isles entrant on 28M Hz. Certificates will be awarded 19 May World Telecommunication Day ICW) (Rules in to those placed second and third overall. Certificates will be awarded to May issue) Region Round-up SSB (Rules in March issue) those placed first, second and third in the rest of the world. 20 May 26 27 May 144MHz Portable (Rules in March issue) 26 27 May CO W W WPX CW (Rules in March and May RECEIVING SECTION issues) Rules as transmitting section except as superseded below. 2-3 June BATC Summertime ATV (Rules in April issue) 1. The general rules for RSGB hf receiving contests, published in the 3 June DF Qualifying Event Dartford Heath (Rules in January 1979 issue of Radio Communication, will apply. May issue) 2. Eligible entrants. British Isles: RSGB members only. 3 June Gwent ATV Group IGW800J) (Rules in April Rest of world: All swls. issue) 3. Scoring. British Isles swls should log only overseas stations in con- 9 10 June NFD (Rules in February issue) tact with British Isles stations participating in the transmitting section of 910 June Diploma Altamira (Rules in May issue) the contest. 16-17 June Microwave (Rules in April issue) SWLs in the rest of the world should log only British Isles stations in 17 June DF Qualifying Event Burton-on-Trent (Rules in contact with overseas stations taking part in the transmitting section of May issue) the contest. 23 24 June Summer 1.8MHz (Rules in May issue) Points scored by all swls will be as in the transmitting section. 23 24 June ARRL FD 4. Multipliers. As transmitting section. 1 July DF Qualifying Event Mid-Thames 5. Logs. Log sheets to be headed: date/gmt, callsign of station heard. 7 8 July VHF NFD (Rules in April issue) RS and number sent by station heard, callsign of station being worked. 15 July 3.5MHz Field Day bonus points, C1S0 points. 15 July DF Qualifying Event Coventry NOTE: In the column headed "Station being worked" the same 29 July 144MHz ORP (Rules in May issue) callsign may only appear once in every six contacts logged. 5 August DF Qualifying Event Salisbury 6. Declaration. Each log must be accompanied by the following 11-12 August European Meteor Scatter (Rules in May issue) declaration: "I declare that this station was operated within the rules of 18 19 August 70MHz Open the contest and I do not hold a transmitting licence in any country of the 19 August OF Qualifying Event Slade world." 1-2 September 144MHz Open and SWL 7. Address for logs. As transmitting section. 1 2 September SSB Field Day (Rules in May issue) 8. Closing date for entries. As transmitting section. 8 9 September International ATV Activity (Rules in April issue! 9. Awards. The Metcalfe Trophy will be awarded to the leading British 16 September DF Final Rugby Isles entrant. The Povvditch Receiving Trophy will be awarded to the October November 432/1,296MHz Cumulative leading British Isles entrant on 28MHz. Certificates will be awarded to 6-7 October 432/1,296/2,304MHz those placed second and third overall. Certificates will be awarded to 13 14 October 21/28M Hz (Rules in May issue) those placed first, second and third in the overseas section. 20 21 October 7MHz Phone 21 October 70MHz Fixed 3 4 November 144MHz CW RSGB European Meteor Scatter Contest rules 3 4 November 7MHz CW 10 -11 November 2nd 1.8MHz 1600gmt 11 August to 1600gmt 12 August 1979 24 25 November BATC SSTV Covering 144 and 432MHz bands. 2 December 144MHz Fixed All entries and check logs to VHF Contests Committee, cío Mr C. Sharpe, G2HIF, 20 Harcourt Road, Wantage, Berkshire OX12 7DQ. The following general rules, published in the January 1979 issue of Radio Communication, will apply: 1, 2, 4b, 5e, 6e, 10a, 13-22. Additional rules Sum mer 1979 1.8MHz Contest rules (al All operators in the British Isles must be members of the RSGB or 1. The general rules for RSGB Hf contests, published in the January have a membership application in progress. 1979 issue of Radio Com munication, will apply. lb) All contacts must be made via the meteor scatter mode of propaga- 2. When. 2000grnt Saturday 23 June to 0100gmt Sunday 24 June. tion. 3. Eligible entrants. All radio amateurs licensed to use 1.8MHz. Multi. (el On each band the score will consist of the product of the number of operator or single-operator entries will be accepted. There will be two stations and GTH locator (big squares) worked. On 432MHz a multiplier sections: of 15 will apply. The final score is the sum of the scores for the two (al British Isles stations (single- or multi-operator) bands. (b) Overseas stations (single- or multi-operator) WI The contest exchange shall consist of: 4. Contacts. CW (Al I only in the 1.8 2MHz band. County code (three (i) both callsigns; letters), as published in the January 1979 issue of Radio Com munica- a standard two-figure ms report; tion, must be sent by all British Isles entrants after the report/serial (iii) the first two letters of the 0TH locator, eg ZL. number. Overseas entrants will only send report/serial number. (e) Conventional (IARUI operating procedures will be used. 5. Scoring. (f) Log keeping. Entrants must keep their own logs in accordance with (a) British Isles stations. Three points for each contact, with a licence requirements. The following information shall be recorded on the bonus of five points for the first contact with each new British Isles contest log: county, and for the first contact with each new country outside the (i) date and time of start of OSO; British Isles. (ri) date and time of finish of OSO; 0,) Overseas stations. Three points for each contact with a station callsign of station worked; in the British Isles (not El!, with a bonus of five points for the first con- (iv) repon sent: tact with each new county. iv) report and locator received; 6. Logs. Column 5 to be headed -Code received". The county code as (vi) number of bursts and pings received; sent must be shown on the top of each log sheet. Entries must be (vii) points and multiplier claimed. addressed to the RSGB HF Contests Committee, c/o R. S. Unsworth, Ig) Contacts must take place directly on the band in use, without 105 Clarendon Road, Hazel Grove, Stockport SK7 4NS, recourse to any other communication medium. There is, however, no 7. Awards. The winner, and second and third placed entrants in each objection to scheduled contacts being arranged. section will receive a certificate of ment.

RADIO CO M M UNICA TION May 1979 451 SSB Field Day 1979 rules Following requests from a number of groups, the rules for this event have baen amended for this year so as to include both an open and a obituaries restricted section. This change is experimental and the inclusion of the restricted section in future SS B ED contests will depend on the support from groups in the 1979 contest. The scoring has also been simplified in accordance with members' wishes. 1. The general rules for RSGB hf contests, published in the January The Society records with regret the deaths of the following radio 1979 issue of Radio Communication, will apply. amateurs: 2. When. From 1500gmt Saturday 1 September to 1500gmt Sunday 2 September. Professor T. P. Allen, MSc. GI6Y W 3. Eligible entrants. Any group of RSGB members resident in the "Tc" Allen died on 19 March aged 79. His amateur activities started in prefix zones G, GD, GI, GJ, GM, GU and GW. This is a multi-operator 1912, and he was licensed in 1926. In 1927 he founded Contact Bureau, contest. one of the Society's most successful experimental links between 4. Operations. Must be from one portable station, not located in a amateurs, and he co-ordinated it for 12 years. He was a dx and cw man permanent building and not using a mains supply. No equipment or of considerable renown, especially in the low power field, and, as a antennas may be installed on the site prior to 24 hours before the start of recognized authority on cypher and cryptography, he made many con- the contest. This does not apply to storage of equipment. tributions to this art. 5. Contacts. SSS only in the 3.5, 7, 14, 21 and 28MHz bands. For many years he wrote reviews of ARRL publications for Radio 6. Sections. Communication. (a) Open section. There is no restriction on the equipment or the antennas which may be used. Mr E. Cockayne, G3DAA (Ial Restricted section. The station shall consist of a transceiver, Eric Cockayne, who died on 16 March, was for many years a member of or a transmitter and receiver. A linear amplifier may be used if the Torbay Amateur Radio Society. Premature retirement, due to ill desired. Only one antenna may be used which must be a single ele- health, gave him the opportunity to operate on all bands, and he was to ment, such as a dipole, inverted-V, long-wire vertical, etc, having be heard daily on a long-standing 1.8MHz net. not more than two support points, and not exceeding 35ft (11 5m) above ground at its highest point. Stand-by equipment may be at Colonel G. Cole, MC, G4EMN hand, but not connected simultaneously with the main equipment. Geoffrey Cole died on 11 March, aged 62. He was secretary of the 7. Scoring. Bournemouth Radio Society, and an RSGB area representative. He devoted much time and energy in bringing amateur radio to those less (a) Contacts with stations in Europe 1 point (b) Contacts with stations outside Europe 5 points fortunate than himself, and as an indefatigable worker for the RAIBC, The totals of points on each band is added to give a grand total. The Shaftesbury Homes and the Lansdowne tape library. He gained the total number of countries worked on each band is added to give a grand Military Cross while serving in Malaysia with the Royal Lincolnshire total. The final score is the grand total of points multiplied by the grand Regiment. total of countries. The RSGB countries list will apply. Entrants are to provide a check list showing the list of countries claimed for each band. Mr J. J. Glendinning, GI3RCH John Glendinning, who died on 25 January, was a well-known character 8. Logs. Separate logs for each band are required. in amateur radio circles in Northern Ireland, his most recent interest 9. Entries. To be sent to RSGB HF Contests Committee, co R. L. Glaisher, G6U<, 279 Addiscombe Road, Croydon CRO 7HY, postmarked being vhf. not later than 17 September 1979. 10. Awards. The leading station in the open section will receive the Mr J. H. T. Hancox, G2HY John Hancox died on 27 February, aged 81. He was a founder member new Northumbria Trophy. The leading station in the restricted section and the entrants placed second and third in each section will receive cer- of the Cray Valley Radio Society. tif icates. Certificates will also be awarded to the stations submitting the leading check log from each continent. Mr H. S. Howells, G3POB "Ron" Howells, who died on 7 March, served for many years in the RAF, and was one of a select group whose service entitled him to membership of RAFARS, RNARS and RSARS. He had previously held the callsign 144MHz QRP Contest rules 9H lAB. A very competent cw operator and member of Tops CW Club, MOO 1700gmt, 29 July 1979 he took delight in a weather reporting net which he founded, and which All entries and check logs to: VHF Contests Committee, c/o Mr F. met most days on 3 -5MHz. Mathews, G8ACJ, Easedale, Woodway, Merrow, Guildford, Surrey GU1 2TF. Mr T. C. Macnamara, G2Tla The transmitter output power shall not exceed 1W cw or p.e.p. If Terence Macnamara died on 17 December 1978, aged 73. He was well transmitter power reduction is required, then brief details of how this known throughout the electronics industry, being a key figure in British was achieved must be given. television, and was a member of the Royal Television Society. The following general rules, published in the January 1979 issue of Radio Communication, will apply: 1, 2, 3, 4a, 5e. 6a, 7a, 8, 9a, 10e, 11a, Mr D. Steele, GI4EMS 12-22. Dennis Steele, who died on 20 February, took up amateur radio late in life, but made up for his late start by an enthusiastic approach to the hobby. He served as secretary of the Bangor and District Amateur Radio Society for a number of years, and was the first secretary of the DF Qualifying Event Dartford Heath Northern Ireland Repeater Group, whose success in com missioning Date: 3 June 1979. GB3NI was a measure of his drive and enthusiasm. His main interest was Map: OS Sheet 188, 1:50,000 Series, Maidstone and the Weald of Kent. cw operation on the hi bands using home-constructed equipment. Assembly: 1300bst for start at 1320bst. Location: Unclassified road off A227 opposite Shipbourne Church, ngr Mr W. G. Wakeham, G2FRX 593 522. Gordon VVakeham died on 19 January, aged 79. He was a member and Competitors requiring tea should notify Mr A. Birchmore, 49 School benefactor of the Torbay Amateur Radio Society and, prior to moving Lane, Horton Kirby (Tel Farningham 862470), by 27 May. 0TH, was a member of Plymouth Radio Club.

We have also been informed of the deaths of: DF Qualifying Event Burton-on-Trent Mr M. Bates. G3GV Q. on 28 February; Date: 17 June 1979. Mr J. Bond, G8EHC, in June 1978: Map: OS Sheet 128, 1:50,000 Series, Derby and Burton-on-Trent. Mr F. P. Healy, G4EVH. on 6 December 1978; Assembly: Lay-by reached from south-bound lane of A33, two miles Mr F. Parker, RS31843, on 1 January; north of Burton, ngr 2e8 270. Mr J. A. T. Pritchard-Gordon, G3PBL, on 19 February; Competitors requiring tea should notify Mr R. Parsons, School Mr H. Punch. G6UR, on 12 February; House, Newborough, Burton-on-Trent ITel Hoar Cross 496) by 8 June. Mr R. G. Stitt, FIS36704;

452 RA DIO CO M MU NICATION May 1979 for private sales, excellent catering and club stands. Free coach ride to Mobile rallies calendar lronbridge Gorge Open Air Museum, the best of its kind in Europe. Fur' ther details from G8DIR, lei Shrewsbury 64273; or G3UKV. QTHR. tel Telford 55416. 6 May—Tulip Time Mobile Rally, Grammar School, Spalding, Lincs. 16 September — Peterborough REtES Mobile Rally, Walton School, Details from G4EMK, tel 07782 2649. Mountsteven Avenue, Peterborough. Talk-in S22 G3DQ W and R B10 via 13 May— Wessex ARG Mobile Family Picnic, Alderholt. Near For• GB3PB, operational callsign to be advised. Usual exhibits, bring and ding bridge. Further details from G4EMN. tel 0202 20027. buy. Details from G3EEL. C1THR, tel 65423 or 62881. 13 May —Open Beach Angling Festival, Gosport and District Angling 30 September—Harlow 8, D ARS Mobile Rally, Netteswell Com- Club, Gosport, Hants. G3NGT will be operating a talk-in station on S20, prehensive School, Harlow. Details from G3KEF, 71 Lodge Hall, Harlovv, 21, 22, 18, for radio amateurs who are interested in fishing. The beach Essex. faces the Isle of Wight, with ample parking and picnic space. Further details from G3NGT, QTHR (enclose sae), tel Gosport 84861. 20 May—East Anglia Radio Amateurs' Picnic, East Anglia Transport Museum, Chapel Road, Carlton Colville, Lowestoft Ion 813841. Open 11am. Talk-in using GB3ATM via GB3NB (R1) GB3P0 (R3), and on S22. Attractions include tram and trolley-bus rides, the Transport Museum, traders, etc. Hotel and caravan park nearby. Details from G3T WQ or Special event stations G3ZNLI. QTHR. 20 May —Welsh Mobile Rally, Barry Memorial Hall, Town Centre, Barry, S Glam. Open llam. Talk-in on GB38C and S22. Trade stands, RSGB GB2EM, 18-20 May bookstall, bring and buy, light refreshments, licensed bar, all under A special event station will operate at the Eisteddfod Mon, Cae Bryn cover. Admission 25p. Beach and amusement park nearby. Further Era, Llanfair P G, Anglesey, Gwynadd. Further details from GW3VVC. details from Reg Rowles GW4F0M, QTHR, tel Cardiff 565656. QTHR. 20 May— Northern Mobile Rally, Victoria Park Hall, Keighley. Trade stands, children's films, refreshments, bar, etc. Details from G8DF2. GB2TFY, 26-Z7 May QTHR. A special event station will be operated in conjunction with "Farming 27 May—Hull Er DARS Mobile Rally, Hull University. Opens 1200bst. Yesteryear", an exhibition of old-fashioned farming techniques, such as Talk-in S22 G8HUC. All the usual trade stands plus some dealing with horse ploughing, and including a museum, from Adamston of Huntly, microprocessors. For xyls and junior ops, a magic show and films. Fur- Nr Huntly, Aberdeenshire, Further information from S. Sutherland. GM4BKV, C1THR, tel 691716, lunch-time and evenings. ther details from G8EAH, QTHR. 27 May —Maidstone YMCA ARS Mobile Rally, Y Sportscentre, Melrose GB2SMC, 9 June Road, Maidstone, Kent. Open 1 lam. Facilities will include free car park- To celebrate the centenary of St Mary's Cathedral Palmeston Place, ing (ample space for everyonel, covered exhibition hall, bring and buy Edinburgh, a special event station will be set up during the cathedral's stall (usual 10 per cent commission to club funds), and talk-in stations. centenary garden féte on 9 June. Further information from G. Marshall, GB2YSC will be operational from 21 to 27 May. Details from J. C. GM4GVT, tel 031-332 3030, evenings. Parker, 42 Mote Road, Maidstone, Kent, tel Maidstone 50350. 3 June— East Suffolk Wireless Revival, near Ipswich, Suffolk. Details GB2LBL, 9-10 June from G4CVB. QTHR. The Lutterworth British Legion is putting on a show, in aid of charity, 10 June —Elvaston Castle Mobile Radio Rally, Elvaston, Castle Country which will include a special event station at Lord Braye Stanford Hall. Park (5 miles SE of Derby, on B5010, signpostecil. 1 lam start. Talk-in by Leics. The main feature of the show will be a re-enactment of the G3EE0 and G3ZBI on GB2ECR, 144MHz frn ch 22, and 432MHz fm Roundheads and Cavaliers Civil War. Further information from G. H. chs SU8 and SUM. Usual attractions including grand bring and buy Dodgshon, G4DNC, tel Hallaton 603. sale, plus full on-site catering facilities. Rally free, but local authority car parking charge of 25p. Further details from G8PTVV, QTHR, tel Derby GB2EF, 9-16 June 752358. A demonstration amateur station will be set up at the Enniskillen Festival 10 June— RAIBC Mobile Picnic, Broadlands Park, Romsey, Hants. to publicise amateur radio, and Fermanagh and its attractions. Further Details from G4CO M. QTHR. information from J. F. MacMahon, GI3ZIA, tel 0365 22955 ext 4775, 17 June —Plymouth Mobile Rally. Tamar Secondary School, Plymouth, days; or 0365 221E8, evenings. Devon. New larger venue. Start 10.30am. Talk-in GB2PRC on 144 and 432MHz, which will be operated by Plymouth RC from 16 to 18 June at GB3LAS, 16 June the rally site. Attractions include PO tvi and tv detector vans. Oracle, A special event station is to be operated from 9am until 6.30pm at usual stands, refreshments and bar. Ample free parking. Further details Joseph Lucas Ltd Sports Ground, Birmingham, on the occasion of the from G4GSZ, QTHR. Tel Saltash (075 55) 6613. company's annual sports. Further information from B. Price, G4DDF, tel 17 June -- HMS Mercury Mobile Rally, HMS Mercury, near Peters)ield. 021-554 5252 ext 608, days; or 0922 51017, evenings. Hants. 24 June— Longleat Mobile Rally, Longleat Park, Warminster. Details GB3SMC, 22 23 June later. SMC is to hold an anniversary exposition and symposium on com- 24 June— Bangor 8- D ARS Mobile Rally, Castlevvellan Forest Park. munications. Unicorn 21, which will include a special event station at Details from GI4AAM, tel 0247 65394. Kempton Manor, Sunbury-on-Thames, Middx. Further information 1 July— Upton Mobile Rally. Upton-on-Severn, Worcs. from J. B. Jenkins, G4CZJ, tel 04216 7333, days; or 0794 516287, even- 22 July—Cornish ARC Mobile Rally. Venue to be announced later. ings. Details from G3VG0, tel 0872 864255- 29 July —Scarborough Mobile Rally and ORM, Scarborough Technical GB8WAS, 22 -24 June College. Details from G4EDR, QTHR. A special event station will operate from RAF Wethersfield (USAF), 5 August—RSGB National Mobile Rally, Woburn Park, Beds. Details Wethersfield, Nr Braintree, Essex, at a Scout air activity camp for from G3MVV. QTHR. members of the Scout Association from Essex and the Greater London 12 August—Derby Mobile Rally. Details from Mike Darn, 22 Reservoir area. Further information from T. D. Mead, G8RX W, tel 01-854 4069. Road, Brockwell, Chesterfield, Derbys. 19 August—Preston Mobile Rally, Park Hall Leisure Centre, Charnock GB2BAZ, 28-30 June Richard, Nr Chorley (new venue— well signposted, just off A49,halfway The RSGB will be operating a special event station at Alexandra Palace, between junctions 27 and 28 on M6). Doors open 11am. Talk•in on S22. London N22, for the Electronics Bazaar, an exhibition with broad elec- Trade stands, bring and buy, bars, buffet, plenty of car parking. Details tronics interest. Further information from M. J. Hawkins, G3ZNI, tel from G8KTM, QTHR. 01-837 8688, days: or Oxshot 3321, evenings. 26 August —Torbay Mobile Rally, STC/ITT Social Club, Brixham Road, Paignton. Talk-in on S22. Trade stands, bookstall, etc. Details from GB2ME M, 30 June G3UIQ, tel Newton Abbot 3025. A special event station will be operated at the Midland Electric Manufac- 9 September — Telford Mobile Rally, Town Centre Malls, Telford, Salop turing Gala Day, a sports day with side shows and home and hobby lapproached via A5 exit off M6, A442 from N and S, or M54 from WI. crafts exhibits. Tho station will be located at the sports field (adjoining Free admission and parking. Jointly organized by Telford DARS and MEM), Reddings Lane, Tysley, Birmingham. Further information from Salop ARS. Attractions include trade stands, exhibitions, "flea market" L. G. Boswell, G4AEJ, tel 021-783 2024.

RADIO CO M M UNICA TIO N May 1979 453 Manchester (UMISTRS)- Wednesday afternoons, cw classes if required; Thursday evenings. The radio shack. UMIST Union bar. Pro- spective members please contact M. P. Doig, G4CQZ,UMIST RS, club news UMIST Union, PO Box 88, Sackville Street, Manchester M60 100. G3CXX/G8FOT active on 1.8;144MHz and, in the near future, on 432MHzi1 • 3GHz. North Western Repeater Group-Informal meetings on the third Thursday in each month, 8pm. "Globe Club", Willows Lane, Accr- ington, Lancs. Details from sec. G3RXH. RSGB affiliated societies and clubs, and RSGB groups, are in- Ormskirk (OARG1- Wednesdays, 8pm. Members' OTHs. For details vited to submit items for inclusion in "Club News" to their please contact G3SZV: or sec G4GCB. tel Burscough 892416. Talk-in on regional representatives (not direct to the editor). 144MHz. Club interests include hi, vhf, uhf. nty, atv, ORP and contests. Items of news and dates of forthcoming events should reach Preston (PARS) - Thursdays, fortnightly; 17, 31 May, 14, 28 RRs by 19 May for the July issue. June." Windsor Castle", St Paul's Square, Preston. New sec John Lof- Club secretaries are QTHR unless otherwise stated. tus, 14 Fishergate Hill, Preston, tel 53508. Salford (Dial House RS) - Wednesdays, 5.30-9.30pm. Dial House, 21 Chapel Street, Sa(ford, Lancs. Net channel 145.25MHz fm-the club station G3WDH monitors this frequency every club night for any other REGION 1-RR W. M. Furness, G3S M M, 16 Coniston Avenue, station. Details from sec G8JCL. c/o M43 at above address. Sale, Cheshire M33 3GT. Stockport (SRS)- Second and fourth Wednesdays in each month; 9 Ainsdale (AARC)-- Thursdays, fortnightly: 17, 31 May, 14, 28 June. May ("Ten-Ten International" by G3VSA), 8pm. Blossoms Hotel, Bux- Ainsdale Scout HQ. Full details from G2CUZ. ton Road, Stockport. Hon sec G3FYE. Visitors always welcome. Club net Sundays. 1 lam clock time, 3,692kHz. Blackburn (East Lancs ARC) - First Thursday in each month, 7.30pm. New venue: "The Globe" Bowling Club, Willows Lane, Accrington. Sec Thornton Cleveleys (TCARSI First and third Wednesdays in each N. Jenkin, G4CGT, 5 Minster Crescent, Darwen. month, 8pm; morse practice from 7.30pm. St John Ambulance Hall, Blackpool (B&DARS) -First Monday in each month. Phone G5ND Fleetwood Road North (next to "Gardner's Arms"), Thornton. Details (Blackpool 64508) for details of venue. from sec G8MKG. Bolton (B&DARS)- First Wednesday in each month (Main meeting). UK FM Group (Western) - First Thursday in each month, 8pm. Grap- Norwich Leisure Centre, Victoria Road, Horwich, Bolton. Following the penhall Community Centre, Grappenhall, Nr Warrington. Sec G3LEQ. AGM in January, new sec is John Debney. G8R WY, 2 Coverdale tel Knutsford 4040. Avenue, Heaton, Bolton. Warrington (WEtDARS)- Tuesdays, 7.45pm. Grappenhall Community Bolton (Edbro Radio Clubl- New club! Details from the sec do Edbro Centre, Bellhouse Lane, Grappenhall, Warrington. Sec G3MMD, tel Ltd, Lever Street, Bolton. Lymm 3533. Bury (BRS)- Tuesdays, 7.30pm. Mosses Community Centre, Cecil Wigan (Douglas Valley ARS)- First and third Thursdays in each Street, Bury. Second Tuesday in each month (Lectures); 10 May month. Shevington Conservative Club, Shevington, Wigan. Details ("Modifying Pye Gear" by G8EU MI, 12 June ("The joys of dxing" by from G4EHK, tel Appley Bridge 3320. Chris Marcroft). Club publicity officer, Mike Bainbridge, G4ESY, 7 Winsford (Mid•Cheshire ARCI - Wednesdays. RAE class 7pm to Rothbury Close, Ainsworth, Bury, tel 061-761 5083. Visitors always 8pm. Morse class every third Wednesday. Technical Activities Centre, welcome. rear of Verdin Building, Verdin Comprehensive School, Grange Lane. Carlisle ICErDARSI - Mondays, 7.30pm. Currock House, Lediard Winsford. Net nights 1.8MHz Monday, 8pm; 144MHz (fml Tuesdays. Hon sec G3JWK. Avenue, Currock, Carlisle. A very full programme of lectures and demonstrations has been arranged for the coming months. Full details Wirral (WARS) - First and third Wednesdays in each month; 16 May from G8DVD. INFO final planning" by A. Smith, G4EFP), 7.45pm. Sports and Chester (CErDARS)- Tuesdays. 8pm. except first Tuesday in each Recreation Centre, Grange Road West, Claughton, Birkenhead. Hon month. YMCA, Chester. New sec, from whom further details can be sec G3DLF. obtained, D. Cutts, tel Grestord 3344. Wirral (WErDARCI -Second and fourth Wednesdays in each month, 8pm. Sports Concourse, West Kirby. Wirral. Hon sec Malcolm Mackin- Douglas (loMARS) - Mondays fortnightly. "Keppel Hotel". Cregny- Baa, Nr Onchan. Sec GD4FVVQ, tel Douglas 22295. tosh, G8NMG, tel 061-334 1027. Eccles (E&DARC) -Tuesdays, 8.30pm. "White Swan". Worsley Road, Swinton. CVV class each week. Sec Chris Harrison, G8KRG, tel 061-789 3538. REGION 2-RR D. S. Smith, "Red Roof", Goathland, Whitby, Leyland (LHARG)- Second Monday in each month, 7.30pm. "Rose Er North Yorks Y022 SAN. Tel Goathland 333. Crown", Ulnes Walton, Leyland. Details from G3XII. Following information is latest received. Liverpool (LErDARSI -Tuesdays, 8pm. Conservative Association Rooms, Church Road, Wavertree. Sec G4EST. Bradford (UBARS)-Thursdays, 7.30pm. N10, Main Building. Sec Liverpool (North Liverpool RC) -For details of meetings please con- G8GOV, 30 Moorfield Drive, Baildon, Shipley, West Yorks. Net fre- tact R. Porter, G3VXK, 11 Cranmore Avenue, Crosby. Liverpool L23 quency 145• 275. DOD; tel 051-928 16)0. Denby Dale (DDE/DARS)- Wednesdays, 7.30pm. Pie Hall, Denby Liverpool University (UoLARSI -Meetings each lunchtime. Member- Dale. Sec G3FGH. Visitors always welcome. ship open to Polytechnic members and associated colleges. Shack in the Goole (G&DARS)- Fridays, 7.30pm (during school term only). Goole Reilly Building, open anytime. Prospective members should contact Grammar School. Details from chairman G3VBI. Geoff Plucknett, G4FKA, UoL, 2 Bedford Street North, Liverpool L7 Halifax (Northern Heights ARS)- Second and fourth Tuesdays in 7BD. each month, 7.45pm. New venue, HQ Bradford Sub Aqua Club, Moun- Macclesfield (M&DRS) - Second Tuesday in each month, 8pm. "The tain, Nr Queensbury. Sec G3U). Old Millstone", Waters Green, Macclesfield, For details of programme, H ornsea (H A RS) - Wednesdays, 8pm. Rear of "Victoria Hotel". Horn- etc, contact Julian Wanden, G8ATI, tel Macclesfield 20651. sea (facing Hornsea Mere). Note new sec Bob Murden, G4BHF, 93 Manchester I ME,. DA RS) - Wednesdays, 7.30pm. Morse practice Gillshill Road, Hull, Yorks HU8 CUL. Club net Tuesdays 8pm, S21 most evenings, lecture on third Wednesday in each month. Newton (145.525MHz fm). Heath Community Centre, 203 Droylsden Road, Newton Heath, Man- Hull (HEtDARS1- Fridays, 8pm. Community Centre, Fountain Road, chester. New sec John Dent, G8OVVY, 76 Lynwood Grove, Auden• Hull. Sec Mrs H. Rodmell, 7 Weelsby Way, Tranby Park, Hessle. shaw, Manchester. Club station G3HOX active on hf and vhf. Hull (Hull University REtES)- Tuesdays, 1.15pm. Room 313B, Manchester (South Manchester AG) -Fridays; 11 May ("Phase- University Union Building, Cottingham Road. Enquiries to G8RPZ. All locked loops" by Mike Small, G4DVII, 18 May (AGM), 25 May amateurs welcome. ("Amateur radio in PAO" by Rob Tenwolde), 1 June ("Frequency syn- Leeds (White Rose RS)- Wednesdays, 7pm. (Lectures start 8pm). thesizers" by Bill Green, G8ALZ), 8 June (Talk by winner of homebrew The Moonovvn Rugby Football Club, Moss Valley, Alwoodley, Leeds contest), 15 June ("The Dolby noise reduction systems" by M. Yonge of 17. Sec G4DZI. Dolby Laboratories; tickets required, no charge but sae to hon sec Leeds (LUUARS) Tuesdays, 8pm. Union Annexe (second floor), please), 22 June ("Operational amplifiers - by Peter Torry, G3SMT), 29 Woodhouse Lane. All new students welcome. Sec G4CNG, QTHR, or at June ("About antennas and feeders" by Bob Heaton, G3JIS), 8pm. "E" block, Lupton Flats. Alma Road, Leeds 6, during term. Mondays (Informal), 8pm. Sale Moor Community Centre, Norris Road, Ot(ey (OREIES) - Tuesdays, 8pm. 14 Back of Court House Street, Sale. Sec W. L. Seddon, G3V(W, 12 Barwell Road, Sale, tel 061-973 Otley. Advance notice of Northern Mobile Rally. 20 May 1979, Victoria 3355. Visitors always welcome. Park Hall, Keighley, Yorks. Sec G8OFZ.

454 RA DIO CO M MUNICATION May 1979 Scarborough ISARSI -Mondays, 7.30pm. Scarborough Technical Stourbridge (StARS)- First Tuesday in each month (Informal), College, Scalby Road, Scarborough. Note new sec G4EDR. 9.30pm. "Bird in Hand" public house, Hagley Road, Oldswinford, Sheffield (SARS)- Third Monday in each month, 8pm. "Sheaf House Stourbridge. 21 May, 4 June (Constructional evening), 18 June, 2 July Hotel", Brarnell Lane, Sheffield. Note new sec G4APV, 321 Fulwood (Constructional evening), 7.45pm. Library, Longlands School, Brook Road, Sheffield S10. Visitors and swis particularly welcome. Street. Stourbridge. Sec G4IP. UK FM Group (Northern) -6 May, 10 June, 7.30pm. Royal Hotel, Stratford-upon-Avon (SuponAErDARC)- Every third Friday, com- Barnsley. Sec G8PLJ. mencing 25 May, 7.30pm. The Clubroom, Swimming Pool, Bridgefoot, Wakefield (WErDARS)- Second and fourth Tuesdays in each month, Stratford. Sec G4EXR, tel Stratford (0789) 5638, weekends only. New 7.30pm. "Holmfield House", Thornes Park, Wakefield. Sec G8RFU. members welcome. York (YARS) - Fridays (except third in each month), 7.30pm. United Sutton Coldfield (SCRS) - Second and fourth Mondays in each Services Club, 61 Micklegate, York. Sec G3WVO, OTHR. month, 7.30pm. Central Library, Sutton Coldfield. Sec G8LTVV. Tam worth (TARS) - Second and fourth Mondays in each month. In- door Sports Centre, Corporation Street, Tamwonh. Sec G4EUF. New members welcome. REGION 3-RR H. S. Pinchin, G3VPE, 61 Cole Bank Road, Hall Telford (T&DARSI - Wednesdays, 7.30pm. Phoenix Centre, Webb Crescent, Dawley. Sec G4HFX, tel Telford 10952) 727357. Visitors Green, Birmingham B28 8EZ. Tel 021-777 1320. welcome. Birmingham (Midland ARS) - 5 June (Construction and club station), Walsall (WARC)- 16 May ("Hospital radio service" by Peter Moxham, 7pm. Brasshouse Centre, off Broad Street, Birmingham. 22 May, 19 G4GJU). 30 May (Discussion- Walsall Show) 13 June, 27 June, 11 June, 8pm. Room 118, University of Aston. Gosta Green, Birmingham. July, 8pm. Forest Com munity Centre, Forest School, Hawbush Road, Sec G8BHE. Leamore, Walsall. Sec G8KML. Birmingham (Slade RS)-First Friday in each month, 7.45pm. The Willenhall (W&DARS)- Alternate Wednesdays commencing 23 May. Committee Room, Church House, Erdington, Birmingham. Sec G4FGF. Little London Community Centre, Bloxwich Road South, Willenhall. Birmingham (South Birmingham RS) -Thursdays II-IF night on the airl, Fridays (Construction and morse classes), 7.30pm. 6 June, 4 July, Sec M. P. Batchelor, 19 Newlands Close, Willenhall, West Midlands WV13 MCI. New members welcome. (Surplus sale), 8pm. "Hampstead House", Fairfax Road, West Heath, Wolverhampton (WARS1-- 21 May (Natternight), 4 June ("Rayner Birmingham B31 3QY. Sec G4G21. by Alan Dennis, G3CNVI, 11 June (Natternight), 18 June ("Short wave Birmingham (University of Birmingham ARS)-Tuesdays during listening" -joint discussion, beginners welcome), 25 June term, RAE and morse class fortnightly, 7pm. Students' Union (above (Natternight), 2 July IRSGB tape lecture), 9 July INatternight), 16 July stage). Club stations G3IUB and G8IUB. Sec G8HTH. COSL card evening, unusual cards welcome), 8pm. Neachells Cottage, Bromsgrove IBErDARCI -8 June (On-site meeting for NFDI, 9/10 June (HF NFD -Signet Fields), 7 July (GB2BRC at Sanders Park), 13 Danescoun Road, Stockwell End, Tettenhall, Wolverhampton VVV9 9PH. Sec G8EDG. July (Quiz), 8pm. Avoncroft Art Centre, Bromsgrove. Sec G4HFP, tel Worcester (W&DARC)-4 June (-Vehicle suppression - by Bryan Stourpon 102993) 3818. Hudson, G3NFX), 1 July (Upton Mobile Rally), 2 July (Discussion Burton-on-Trent (BonTErDARS)- Wednesdays, 8pm. Stapenhill In- "Yesterday's rally"), 8pm. "Old Pheasant", New Street, Worcester. Sec stitute, Main Street, Stapenhill, Burton-on-Trent, Sec G3ACR. G4EKG, tel Evesham (03861 41105. New members and visitors welcome. Cannock Chase (CCARS)- 7 June, 5 July, 8pm. "Lynwood", Old Penkridge Road, Cannock. Other Thursdays, 8pm. "Acorn" public house (rear room), Town Centre, Cannock. Sec G8FWZ. Visitors welcome. Coventry (CARS( - 18 May (Visit by RSGB President John Bazley, G3HCT), 25 May (VHF night on the air), 1 June (Open night), 8 June (DF practice - see sec), 15 June (Night on the air), 22 June (Social even- REGION 4-RR N. J. H. Grassby, G4CPY, 22 St Cuthberts Avenue, ing -see sec), 29 June (Treasure hunt -see sec), 6 July (Preparations Great Glen, Leicester. Tel 053 759 3387. for VHF NFD), 13 July, 8pm. Baden Powell House, 121 St Nicholas Derby (D&DARSI -16 May ("144MHz df" theory and discussion), 23 Street, Radford, Coventry. Sec G8OMB. Visitors welcome. May (Night on the air), 30 May ("144MHz df" practice), 6 June (Bring Coventry Technical College (CTCARS) -Mondays and Thursdays, and buy sale). 13, 20, 27 June, 7.30pm. Morse classes Tuesdays and 7pm. Winfrey Annexe of the college. Sec G8ISJ. Fridays, 7pm. 119 Green Lane, Derby. Sec Jenny Shardlow, G4EYM. Coventry (University of Warwick ARS( - Wednesdays during term, Derby (NH ARG)- Fridays, 7.30pm. Nunsfield House, Boulton Lane, 7pm. Cryfield Farm, University of Warwick. Talk-in on 520, or contact Alvaston, Derby. Sec Ian Cage, G4CTZ. G4BXI or G4DCVV, Hurst Flat 40, Cryfield Village, University of War- Glenfield (Leicestershire Raynet Group)- Monthly. County Hall, wick. Glenfield. Further details from M. G. Barker, G8CAC. Dudley 1DARC)- Second and fourth Tuesdays in each month, Grimsby (GARCI -First and third Thursdays in each month, 8pm. 7.45pm. Central Library, Dudley. Sec Norman Rock, 28 Conway Close, Alexandra Club, Cleethorpes. High Acres, Kingswinford, Brierley Hill DY6 8PT. Leicester (LRS)- Mondays, 7.30pm. Club House, Gilross Estate Cot- Hereford (HARS)- First and third Fridays in each month, 8pm. Civil tage, off Groby Road, Leicester. Defence HQ, Gaol Street, Hereford. Sec G4CNY. Leicester (LPARS)- Mondays, Wednesdays, Thursdays and Fridays, Lichfield (Chad RC)- Alternate Wednesdays, commencing 23 May, lunchtime during term. Leicester Polytechnic. Sec R. Newstead, 8pm. The Naval Club, Burton Old Road, Lichfield. Sec G4ESK. G3C WI, 24 Richmond Road, Leicester. Lichfield 1LARS)- First Monday and third Tuesday in each month, Lincoln (LS WC)- Second and fourth Wednesdays in each month. Lin- 8pm. "Swan" (bar), Lichfield. Sec Ted Bowen, RS33003, tel lbstock coln Corporation Social Club, Waterside South, Lincoln. Sec R. Shaw, 10530) 60396. G3VRD. Mid-Warwickshire (MWARS(-First and third Mondays in each Mansfield (MARS)- First Friday in each month, 7.30pm. "New Inn", month, 8pm. 61 Emscote Road, Warwick. Sec G8CXL. Westgate, Mansfield. Redditch (R RCI -Second and fourth Thursdays in each month, 8pm. Matlock (Derwent Valley ARS) - First Monday in each month, WRVS Centre, Ludlow Road, Redditch. Sec G3EVT. 7.30pm. "The Royal Oak", Tansley, Nr Matlock. Guest speakers each Rugby (RATS)- Wednesdays, 7.3 m. Cricket pavilion entrance to B month. Building, Rugby Radio Station, A5 trunk road, Hillmorton, Rugby. Sec Melton Mo wbray (MMARS) -Third Friday in each month, 7.30pm. G4ECO. St John Ambulance Hall, Asfordby Hill, Melton Mowbray. 18 May Shrewsbury (Salop ARS)- Thursdays, 8pm. "Albert Hotel", (Possible visit to Enderby police control room), 15 June 1Possible visit to Smithfield Road, Shrewsbury. Sec G3UDA. New members welcome. Radio Trent). Sec Richard Winters, G3NVK. Solihull (SARS)- 15 May ("Building and demonstration of a teletext Nottingham (ARCON)- Thursdays, 7.30pm. Sherwood Community decoder for Ceefax and Oracle" by Tony Rowsby, G4CQS), 19 June Centre, Mansfield Road, Nottingham. Sec M. Shaw, G4EK W. ("Satellites for the amateur service" -to be confirmed), 7.30pm. The Nottingham (Trent Polytechnic RS) - Wednesdays. Newton Manor House, High Street, Solihull. Morse classes available. Sec Building, Room 105. Further information from the chairman Paul Robin- G4BBT. New members and visitors welcome. son, via Students' Union, Trent Polytechnic. Stoke-on-Trent (North Staffs ARS)- First and third Mondays in each Nottingham University (NURC)- Tuesdays. Contact R. Dixon, month (Lectures, etc), other Mondays INatternights, Raynet and club G4BVY, clo Students' Union, Nottingham University. station, G4BEM), 7.30pm. Harold Clowes Community Centre, off Scunthorpe (SARC)- Tuesdays, 7.30pm. The Hobbies Centre, Dawlish Road, Bentilee, Stoke-on-Trent. Sec GBORU. New members Franklyn Crescent, Scunthorpe. Sec J. Stace, G4FUH. welcome. Stoke-on-Trent (SonTARS) - Thursdays, 7.30pm. 2a Racecourse The new RR would be pleased to hear from all club secretaries in the Road, Oakhill, Stoke-on-Trent. Sec G4C WN. region, either by post or telephone.

RADIO CO M MUNICATION May 1979 455 High Wycombe (Chiltern ARCI 30 May, 8pm John Hawkins Ltd, Victoria Street, off Oxford Road (A40), High Wycombe. Further details from sec G4FRL, tel Kingston Blount 52006. Maidenhead IMErDARS)- First Thursday and third Tuesday in each month. The Red Cross Hall, The Crescent, Maidenhead. New sec P. J. Patick, G3TVVG. Tel 06285 25275. Newbury (NErDARS)- Second Tuesday in each month. Newbury Technical College. Details from sec G8LTD, tel Newbury 46078. Newport Pagnell (Milton Keynes ARS)- 14 May ITalk, "Radio and tv interference"), 8pm. Lovatt Hall, Newport Pagnell, Bucks. For further details contact F. Walters, Staff Residence, Milton Keynes College of Education. Oxford (O&DARS)- Second and fourth Wednesdays in each calendar month, 7.30pm. Civil Service Social Club, Marston Road, Oxford. Sec G48HR. Oxford University (OURS)- Please contact sec M. Evans, G8LTE, Worcester College, Oxford, for meeting details. Reading (RARC)- Details from sec Chris Young, G4CCC.

REGION 7-RR D. A. G. Pedder, G3LFX, 97 Elgar Avenue, Tolworth, Surbiton, Surrey KT5 9JS. The AG M of the St Dunstan's Radio Society was held on 27 Addiscombe (AARCI -Tuesdays, 9.15pm. "Spreadeagle", Portland February. and at the luncheon afterwards the guests included Road, South Norwood. Sec G3SJX. Ashford (Echelford ARS)- Second Monday and last Thursday in each Louis Varney. G5RV, representatives of RNARS, RSARS, month, 7.30 for 8pm. The Hall, St Martin's Court, Kingston Crescent, RAFARS. RAIBC, Mid-Sussex and Brighton clubs, and members of St Dunstan's staff at Ian Fraser House. Ashford, Middx. Sec G3TDR, tel Staines 55513, Bexley Heath (North Kent RS)-8pm. St Mary's Institute, 2 North The G3MO W Memorial Trophy was awarded this year to Nor- man French, of St Dunstan's headquarters, for the encourage- Cray Road, Bexley. Sec G3VFD. Cou(sdon (CATS)-Sec A. R. Bartle, G6HC, tel 01-684 0610. ment, help and advice given by him to St Dunstan's radio amateurs over many years. The photograph shows Norman Cray Valley (CVRS)- First and third Thursdays in each month; 17 May I"Personal computers and amateur radio" talk and demonstration by French (r) receiving the trophy from Louis Varney, while in the background is Bill Shea, G4AUJ, chairman of St Dunstan's Radio G8KDC and G8LFCI, 7 June ("AMSAT" -confirmation from sec), 21 June (Natternight), 5 July ("SSTV" - confirmation from sec). 7.30 for Society 8pm. Christchurch Centre, High Street, Eltham, London SE9. Sec G4FUG. Croydon (Surrey Radio Contact Club) - First and third Wednesdays in each month; 6 June ITalk by an equipment supplier), 7.30pm. TS REGION 5-RR R. E. G. Kendall, G8BNE, 19 Willow Green. Terra Nova, 34 The Waldrons, Croydon. Sec G4FFY. Needingworth, Huntingdon PE17 3SW. Crystal Palace (CPEtDRS) Third Saturday in each month, 8pm. Bedford (B&DARC) - Wednesdays, 8pm. Ravensden. Sec G4FFC. Emmanuel Church Hall, Barry Road, London SE22. First Tuesday in each month (Open house). Members' QTHs. Sec G3FZL. Cambridge (C&DARC)- Fridays. 7.30pm. Air Training HO, Guildford IGErDRS) -Second and fourth Fridays in each month; 11 Newmarket Road. Sec G4BAO. May I"Early days as an amateur" by Arthur Milne, G2MI), 8pm. Model Cambridge (CU WS)- Mondays during full term (Speakers). Other Mondays (Informal), evenings. Queen's Bar. Full details from Adrian Engineers HQ, Stoke Park, Guildford. Sec G4BHQ, tel Guildford 76375. Guildford (University of Surrey E&ARS) - Informal meetings, lunch- Langford, G8POP, St John's College. times during term. Lower Bar, Union House, G8AHK is active on vhf, Corby (CARG) Fridays, 7.30pm. Hightrees Scout Centre. The Nook, and WIG° on hf. Skeds and (DSOs always welcome. Sec G8M10, tel Corby. Sec G8MLA. Guildford 71281. Dunstable (DDRCI- Fridays, 8pm. Chews House, 77 High Street Kingston IK&DARS)-Second Wednesday in each month, 8.15pm. South. Sec G3HJF. Berrylands Scouts and Guides HQ, Stirling Walk, Raeburn Avenue, Sur- March IMEtDRAS)-Tuesdays, 7.30pm. 2 Grays Lane. Sec G8GNE. Northampton (NRC) - Thursdays, 8pm. Kingsthorpe Community Cen- biton. Sec G4APG. tel 01.399 8113. The society is seeking a smaller and tre, Thornton Park, Kingsthorpe, Northampton. Details from sec I. P. A. more convenient meeting place. New Cross (Clifton ARS)-Fridays, 8pm. 225 New Cross Road, Lon- Scon-lversen, 35 Milverton Crescent, Abmington Park, Northampton. don SE14. Details from R. A. Hinton, 42 Sutcliffe Road, Welling. Peterborough (GPARCI-Fourth Thursday in each month, 7.30pm. Redhill (Reigate ATS)- Third Tuesday in each month, 8pm. Constitu- Southfields Junior School, Stanground. Peterborough. Sec G4FDF. tional Centre, Warwick Road, Redhill. First Tuesday in each month. Peterborough (PREtES)- 18 May (HF DF Contest, 1930bst on 1,980kHz, using G3RED/P -starting QRA to be announced). For further "Marquis of Granby -. Hooley Lane, Redhill. Sec G3XSZ. Sutton Et Chasm ISEtCARSI -Wednesdays, 7.30pm. Ray's Social details contact G3EEL. Shefford IS&DARSI -Thursdays, 8pm. Church Hall. Hon sec Club, London Road, North Cheam. Sec G2DMR. G4DAQ. Thames Ditton (Thames Valley ARTS) - Giggs Hill Green Library. St Neots (Foster Cambridge RC) - Tuesdays. 8pm. Foster Cambridge Giggs Hill Road, Thames Ditton. For meeting details contact sec Ltd, Howard Road, Eaton Socon, St Neots. Details from P. Dineen, 5 G3ZNVV. Tolworth (Decca ARG)- New club) First Thursday in each month, Reynolds Drive. Little Paxton, St Neots. 8pm. Decca Sports and Social Club, Kingston Road, Tolworth. Sec G3NFV, tel Leatherhead 72587. Wimbledon (W&DRS)-Second and last Fridays in each month; 25 May ("Single conversion and direct conversion receivers" by Robin REGION 6-RR F. S. G. Rose. G2DRT, 84 Cock Lane, High Hewes, G3TDR), 8pm. St John Ambulance HG, 124 Kingston Road, Wycombe, Bucks HP13 7EA. Tel Penn 1049481) 4240. Wimbledon. Sec J. W. Todd, tel 01-540 9031. Banbury (BARS)- First Friday in each month, 7.30pm. The General Foods Sports and Social Club, Spriceball Park, Banbury. Sec S. L. Terry, G8OCT, tel Banbury 4769. Bracknell (BARC)- Mondays, 8pm. Coopers Hill Centre (adjacent to station). For meeting details please contact sec D. Williams, G4CVN, tel REGION 8-RR D. N. T. Williams, G3MDO, "Seletar", New House Windsor 56096. Lane, Thanington, Canterbury, Kent. Burnham Beeches (BBRC)- First Monday in each month, 8pm. Brighton (B8DRS)- 8pm prompt. Catholic Church Hall, Bristol Road, Hedgerley Scout Hut, Hedgerley, Nr Slough, Bucks. Sec G8DAY. New Brighton. Details from N. Hewitt, G8JFT. members, visitors and swls welcome. Burgess Hill !Mid-Sussex ARS) -7.45pm. Marie Place, Burgess Hill. Harwell (Atomic Energy Research Establishment RC)- Fridays, Details of future events from G3PEQ. lunchtime. The Shack, AERE Harwell, Didcot, Berks. For further Canterbury (East Kent RS1-7 June (Quiz). Further details from meeting details contact sec G8DVK. G8GHH or G3MDO.

456 RADIO CO M MUNICATION May 1979 Chichester (CErDARC)- First Tuesday and third Thursday in each Exmoor (ERC)- Second and fourth Thursdays in each month, 7.30pm. month. Lancastrian Boys School. Details from G4ETU, tel 0243 88069. "Loughrigg". East Street, South Molton. Full details from Dave Stone, Crawley ICARCI- Details of future events from G3MGL, tel 0293 tel North Molton 377. 20986. Exmouth (EARC)- Alternate Wednesdays, 7.30pm. Rolle College, Ex- Dartford (DHDFC) -Second Friday in each month. Scout House, mouth. Full details from Dave Hanson. 67 Carter Avenue, Exmouth, tel Broomfield, Dartford. Details from Jeanette Maggs, 25 Leybridge Court, 75482. Eltharo Road, Lee, London SE12. Nevyquay (NErDARS) -Alternate Wednesdays, 7.30pm. Treviglas Dover (South East Kent YMCA ARC)- Wednesdays, 7.30pm. Fur- School, Newquay. Full details from new sec Ted Warne, G3YJX, tel ther details from G8PZA or G8KEN. Wadebridge 2772. Eastbourne (Southdown ARS)- First Monday in each month. Details North Devon (NDRC) -Second and fourth Wednesdays in each from G8KQN. or pro G3LFZ. month. New chairman is G3VGJ. For full details of meeting places con- Gravesend (GRSI- Mondays, 7.30pm. "Windmill Tavern", Shrubbery tact G4CG. tel Barnstaple 3636. Road, Gravesend. Details of future events from G4GML. Plymouth (PRC) - Alternate Mondays, 7.30pm. Whitleigh Methodist Hastings (HEBRC)- Fridays. 479 Bexhill Road, St Leonards-on-Sea, Church, Budhead Road, Whitleigh, Plymouth. Full details from L. Sussex. Third Wednesday in each month, 7.30pm. ITT Social Club, England, 62 Fullerton Road, Milehouse, Plymouth, tel 58841. Crown House, 57 Marina, St Leonards-on-Sea, Sussex. Details of Saltash ISEIDARC1- First and third Fridays in each month, 7.30pm. events from G4FET. Burraton Toc -H Hall, Saltash. New sec D. Bunce, 47 Hobbs Crescent, Horsham IHARCI - First Thursday in each month. Parish Rooms, The Saltash, tel 2839. Causeway, Horsham. Details of future events from A. C. Wadsvvirth, Torbay (TARS)- Fridays, with special meeting on last Saturday in each G3NPF. month, 7.30pm. Bath Lane, rear of 94 Belgrave Road, Torquay. Full Kent Repeater Group-Details of membership from G3XDV, 5 Lambs details from G3U10, tel Newton Abbot 3025. Torbay net each weekday Walk, Whitstable, Kent. 3.760MHz. Mondays to Fridays 10.30am, Saturdays 9.30am. 144MHz Maidstone (MY MCAARS)- Fridays; First and third in each month net on S22, Mondays 8pm. devoted to the beginner; 7.30pm. Y Sports Centre, Melrose Close, Loose, Maidstone. 27 May (Mobile rally-see calendar). Details of future events from sec J. A. Hastie, tel Medway 251387. Medway IMARTS)- Details of events and venue from G4EVY. Sussex Repeater Group-Information from G8HVV. REGION 10-RR R. G. Barrett, G W8HEZ, 23 Carshalton Road, Tunbridge Wells (West Kent ARS)- Alternate Fridays; 11 May (Con- Beddau, Pontypridd, Glam. struction contest), 25 May ("Homebrew EQ' Uy G3KFE, editor Short Following information is latest received. Wave Magazine), 8 June (HF/VHF NFDs arrangements), 22 June (Let- Barry IBCoERSI - Thursdays. 8pm. In addition, special events are lure by the British Vintage RS), 6 July (Editor Radio Communica- arranged every fortnight. New venue: Weycook Cross, Five Miles Lane, tion-provisional). Adult Education Centre, Monson Road, Tunbridge Barry. Details from new sec M. E. Woodberry, GW8OPK, 60 Pen -y- Wells. Tuesdays following the Fridays (Informal). Drill Hall, Victoria Craig, Rhiwbina, Cardiff. tel 613635. Road. Details from Brian Castle, G4DYF. Blackwood (BARS) -Fridays. 7pm. Oakdale Community Centre, Worthing (W&DARCI -Tuesdays, 8pm. Adult Education Centre, Oakdale, Blackwood, Gwent. Details from GW4BLE, 10 Llanthewy Union Place, Worthing. Details from G8MSQ. Road, Newport, Gwent. Bridgend (B&DARCI-Second Wednesday in each month, 7.30pm. NCB Social Club, Tondu, Bridgend. Details from sec GW48DV. Cardiff ICRSGBGI-Second Monday in each month, 7.30pm. Pant- REGION 9- RR H. W. Leonard, G4UZ, 4 Start Bay Park. Strata. mawr Inn, Pantmawr Estate, Cardiff. Details from GW3GHC. Dartmouth TC16 ORY. Merthyr (Hoover ARS)- Mondays, 7.30. Hoover Social Club, Pen- Camborne (Cornish RAC)- First Thursday in each month; 7 June trebach, Merthyr. Details from GW3RNC. ("Microprocessors" by G4CDU), 5 July (''Radio interference" by Newport (NARC)- Mondays, 7pm. Adult Education Settlement, G3VVVK and G3FXL), 7.30pm. SWEB Clubroom, Pool, Camborne. 22 Brynglas Road, Newport. Details from GW8MER. July (Mobile rally). Full details from G3VG0, tel Devoran 864255. Cor- Pembroke (PRSGBG)- Last Friday in each month, 7.30pm. Defen- nish net each weekday 10am on 3-715MHz, and on Sundays 1 lam on sible Barracks, Pembroke Dock, Dyfed. Details from sec GW3XJ0. 3.682MHz. Visitors always welcome at club meetings. Pontypool (PRSGBG) Tuesdays, 7pm. Education Settlement, Park Exeter (EARS1-Second Monday in each month; 14 May ITalk by Hill Road, Pontypool. Details from GW3JBH. G3OFY). 11 June (Construction nightl, 16 July (Surplus sale), 7.30pm. Port Talbot (British Steel Corporation ARS) -Thursdays, 7.30pm. Community Centre, St Davids Hill, Exeter. Full details from Jack BSC Sports and Social Club, Margam. Port Talbot. Details from Bawden, 232 Exwick Road, Exwick, Exeter EX4 2BA. G W4BDV. Exeter University (EUARS( -Full details from sec G4EXT, c/o Rhondda (RARS) Every other Thursday, 7.20pm. Transport "Devonshire House", Stocker Road, Exeter. Employees Club, Forth. Details from GW3PHH.

Fifty amateurs gathered at Exeter University ARS headquarters on 18 March to hear a very inform- ative lecture on international and intercontinental com munication on 144 and 432MHz, presented by Chris Bertram, G4DGU, with the assistance of Keith Fisher, G3VVSN. At the same meeting RSGB Zone D Council member Les Hawkyard, G5H D, answered questions of regional interest, and on band planning for the future and licensing matters. L to r: G3WSN, G4ENZ, G4DGU, G5HD, G8PUC. G4EXT and G8KQB. Photo: M. Blythe, G4HFO

RADIO CO M MUNICATION May 1979 457 Sully ISEH3S WC)-- Mondays fortnightly, 7pm. Sully Bowls and Social Glenrothes (GErDARC)- Third Sunday and every Wednesday in each Club, 58 South Road, Sully, Cardiff. Details from David Hughes. 13 month; 20 May (Final NFD preparations), 17 June (HF NFD post Nailsea Court, Sully. mortem), 15 July I VHF NFD post mortem), 7.30pm. Old Nursery School Swansea (SARC) - Tuesdays fortnightly, 8pm. West Cross Hotel, Building, Provosts Land, Douglas Road, Leslie, Fife. Details from West Cross. Swansea. Details from sec GW8CMA. GM4EJI. Swansea ISARSI - Tuesdays fortnightly, 8pm. Sketty Park Sports and St Andrews (University of St Andrews RfiES)- Details from Social Club. Anewin Way, Sketty Park. Swansea. Further details from Physics Department, North Haugh, St Andrews. G W4HAT. Intending visitors must contact sec before arrival. Swansea (University College of Swansea RS) -Mondays, 7.30. Room 801, Applied Science Building. Details from sec J. Morris, 1 Hadland Terrace, West Cross, Swansea, tel 68675. REGION 14-RR I. L. McKechnie, GM8DOX, 42 Newton Crescent, Dunblane FF15 ODZ. Following information is latest received. Ayr (AARGI -Community Centre, 24 Wellington Street, Ayr. Sec REGION 11- RR P. H. Hudson, Dinas Dinlle, Caernarvon. GM3THI. Bangor (UCN WARS) Thursdays, 7.30pm. Small Lecture Theatre, Dumfries (DErDARG)- Details from GM3VV0J. School of Engineering Science, Dean Street, Bangor. Falkirk (Stirlingshire ARGi- Details from GM4DGT. Conway Valley ICVARC)- Second Thursday in each month; 10 May Glasgow (West of Scotland ARC) - Try GM4FDM for information. (Visit to be arranged), 14 June (AGM), 12 July (Fox hunt), 7.45pm. The Greenock IGErDARCI -Tuesdays and Fridays, 7.30pm. 22 Inverkip Ouaries, Llandulas, Colwyn Bay. Street, Greenock. Details from sec GM3LYI. Rhyl (R&DARC)- Fourth Thursday in each month. Ambulance Sta- Helensburgh (HARC) - Try GM4FEC) for information. tion, Coast Road, Rhyl. Other Thursdays (On the air on 144•00MHz), Motherwell (Mid-Lanark ARS)-Alternate Fridays, commencing 2 8pm. Newcomers and visitors welcome. March, 7.30pm. Wrangholm Hall Community Centre, Jerviston Street, Motherwell. RAE and morse classes every Friday. All details from sec GM4FKD. Stevenson (Ardeer RCARS) - Details from GM3SUL. REGION 12- RR F. Hall, GM8BZX. 45 Priory Cottages. Lunanhead, Stirlingshire (SARG)- New group! Starting up initially to put a 70cm Forfar, Angus DDB 3NR. repeater on the air. Anyone welcome to join including members of the Aberdeen (ARS) - Fridays, 7.30pm. 80 Guild Street, Aberdeen (next to diminished Falkirk Et District RC, to enlarge club activities. Details from "Station Hotel" immediately ad¡acent to railway station). Programme sec GM3POK, or GM4CXF. details from sec GM4BKV. Dundee (Kingsway Technical College ARC1- Tuesdays, 6.30pm; All secretaries please note the closing date for items for insertion in the (6.30-7pm, morse practice; 7 8pm, arranged lectures; 8-8.15pm. cof- next Club news at the beginning of this column. fee; 8.15-9pm, any other business and general discussion). Dundee Technical College. Sec GM4FLP. Offer of the use of premises, comprising lecture room, committee room Elgin (Moray Firth RS) - Wednesdays, 7.30pm. Elgin Technical Col- and shared use of a workshop, on any day except Thursday and Satur- lege. Sec GMBOVN. The club extends a warm welcome to all licensed day. Any interested parties please contact ASTRA Ltd, 49 Almada amateurs and svvls in the area who may be hesitant in coming along. Street, Hamilton. (Opposite Bell College and court building.) Non-members will be asked to pay a donation of Wp per meeting, with a limit of two attendances before joining the club. All secretaries please note that RR14 has an Ansaphone available for Invergordon (Easter Ross RCI - Every second Tuesday. 100 High their use. Tel Dunblane (0786) 822212. Street, Invergordon. Details from sec GM4DKL. Inverness (Technical College ARC) - Every second Wednesday, 6.45pm. Room C30. Sec W. Lee. 36 Old Mill Road, Inverness, Kirkwall- Members now meet on a few occasions during the year to discuss various aspects of amateur radio. Information from GM3IBU, tel REGION 15- RR I. J. Kyle, GI8AYZ, 2 Galgorm Gardens, Ballymena, Kirkwall 3232. Co Antrim 8142 IBA. Perth (P&DARGI -Tuesdays. 7pm. Perth Technical College. Sec Ballymena (BRC)-Tuesdays, IRAE and morse classes), 7.30pm. GM4DCU. The Perth repeater, GB3PR, is now operational on channel Fridays (Club night). Sundays (Special projects), 3pm. 86 Old R3- coverage reports would be welcome. Cullybackey Road, Ballymena. Sec GI4HCN. Bangor IBErDARSI - First Friday in each month, 8pm. Redcliffe Hotel, Bangor. 24 June IMobile rally). Castlewellan Forest Park, Sec GI4AAM. Belfast (BRSGBG) - Third Wednesday in each month. (except July and REGION 13-RR A. B. Givens, GM3YOR, 41 Veronica Crescent, August). 90 Belmont Road, Belfast 4. Details from GI3USS. Kirkcaldy, Fife KYI 2LH. Tel Kirkcaldy (0592) 200335. Belfast (CoBY MRC)- fuesdays, 7pm; Saturdays, 2.30pm. Fourth Berwick-upon-T weed )BErDARSI -First and third Fridays in each Floor, YMCA, 12 Wellington Place, Belfast. Sec GI8MOR. month, 7.30pm. Avenue Hotel, 122 Marygate, Berwick-upon-Tweed, Belfast (Queen's University of Belfast RC) - Tuesdays during term, Details from sec GM8110. 8pm. Queen's University, 37 Fitzwilliam Street, Belfast 9. Dunfermline IDARSI -Second Wednesday in each month, 7.30pm. Dromore llagan Valley ARS) - First Monday and third Tuesday in CCTV Studio, Pittencrieff School, Maitland Street, Dunfermline. Details each month. 8pm. Scout Hall, Mossvale Road, Dromore, Co Down. from sec GM3MGX, tel Limekilns 313. Details from AR GI4GDV. Edinburgh (E&DARC)- Tuesdays, 7.30pm. City Observatory, C,atton Mid-Ulster (MURSGBG)- First Sunday in each month. GI4BAC's Hill, Edinburgh. Details from sec GM8MJV, tel 031.663 2033. 0TH. 20 May (Get together). Parkanaur. Details from AR GI8RJ W, tel Edinburgh (Ferranti Recreation Club AR Section)- Membership is Armagh 524453. restricted to company personnel. Details from GM8JKG, tel 031-441 5684. Visits by other clubs by prior arrangement. Edinburgh (GB3ED Repeater Group) - GB3ED is a 432MHz repeater situated at Napier College, Edinburgh, and operating on channel RB14 (output 433. 350MHz, input 434- 950MHz). Details of group meetings REGION 16 - RR M.S. Appleby, G3ZNU, 45 Cedar Avenue, from GM3GBX, tel 031-447 2611. Kesgrave, Ipswich IP5 7HA. Edinburgh (Heriot Watt University ARC) - Wednesdays, 2pm. Aerial Bury St Edmunds )BStERS) - Third Tuesday in each month, 7.30pm. Laboratory, Top Floor. Mountbatten Building, 31-35 Grassmarket, Edin- Red Cross Headquarters, Mustovv House, Eastgate Street, Bury St burgh, Edmunds. Details from John Munro, 29 Angel Hill, Bury St Edmunds. Edinburgh (Leith Nautical College ARC)- First and third Thursdays Chelmsford ICARS)- First Tuesday in each month, 7.30pm. Marconi in each month, 7.30pm. Leith Nautical College, 24 Milton Road East, College, Arbour Lane, Chelmsford. Details from R. Brooks, 30 Rowan Edinburgh 15. Drive, Heybridge, Maldon. Edinburgh (Lothians RSI -Second and fourth Thursdays in each Colchester (CRAI -Thursdays, fortnightly, 7.30pm. Main Block, Col- month. 10 May (Talk by GN18FFX), 7.30pm. Riddles Court, High Street, chester Institute, Sheepen Road, Colchester. Details from Frank Howe, Edinburgh. 24 May (Operating night), 14 June (AGM), 28 June (For- G3FIJ. ward planningl, 7.30pm. Cannonball House, High Street, Edinburgh. Felixstowe (FARCI - Tuesdays (Informal). Felixstowe Golf Club. Details from GM4DIJ, tel 031-337 7311. Details from John Hobin, G3XIX.

458 RA DIO CO M MUNICATIO N May 1979 Great Yarmouth (G YRS) - Last Thursday in each month, 7.30pm. 67 Southampton (SRSGBG)- First Monday in each month: Lanchester Southdown Road. Great Yarmouth. Details from Tony Besford, Building, Southampton University. Wednesdays: The clubroom, Kent G3NHU. Road. Both at 7.30pm. AR G4CO M. Harlow (H&DRS1-Tuesdays, 8pm. Mark Hall Barn, First Avenue, South Dorset (SDRS) -7.30pm. Lecture Hall, South Dorset Technical Harlow. Details from G3WUX. College, Newstead Road, Weymouth. Details from sec G3ZGP. Harwich (HErDRA)- Thursdays, 7.30pm. Harwich Adult Education Swindon ISErDARC)- Alternate Wednesdays, 7.45pm. Clubroom, Centre. Details from sec Tony Free, G4EYE. Oasis Leisure Centre. Details from sec I. Browne, 59 Kitchener Street, Haverhill (HErDRSI- Fridays, 7.30pm. Steeple Bumpstead Road, Swindon. Haverhill. Further details from Chris Kitchener, G8IMI, tel Haverhill 2852, Winchester (WARC)-- First Friday and third Thursday in each month, evenings. 7.30pm. "Crown Hotel - . Sec Chris Jackson, BR539944, 69 Buriton Ipswich (IRC) -Second and last Wednesdays in each month, 7.30pm. Road, Harestock, Winchester. Morse classes every Wednesday, 7.30pm. Ranelagh Road School, Ipswich. Details from sec Pat Gillen, G4GV W, 37 Lancing Avenue, Ipswich. Loughton (L&DARS) - Fridays, fortnightly; 18 May (Informal), 1 June REGION 18- RR W. A. Ricalton. G4ADD. 4 South Road, ("Microprocessors and amateur radio" by Ted Harrison, G8NPF, and Longhorsley. Morpeth, Northumberland. John Ray, G8DZHI, 15 June (Informal), 29 June (Subject to be arranged), 8pm. Loughton Hall, Rectory Lane, Loughton. Further details from Following information is latest received. Durham (DUARS)- Alternate Wednesdays during term, fortnightly sec John Ray, G8DZH, tel 01-508 3434, evenings. Lowestoft (LErDARC)- Fridays; 18 May (Early summer df hunt), 25 from 1 November 1978. Physics Dept, Durham University. Details from May (Visit to Sizewell power station), 1 June (Members evening and G3ZJY or G4F0P, or A. Jarrett, G4FRZ, Van Mildert College. Durham. External members especially welcome. display of modern gear), 15 June ("A retractable mast for vhf" by G3GNK), 29 June ("Was Marconi right?" tape/slide lecture by Pat Easington lEARErECI -Tuesdays and Thursdays, 7.30pm. Easington Gowan, G310RI, 7.30pm. North Suffolk Teachers' Centre, Lovewell Village Workmen's Club. RAE and morse tuition if required (the club has Road, Lowestoft. Details from Brian Clay, G8GGJ. a good pass record). Details from sec G4GXI. All welcome. Martlesham (MRS)- First Wednesday in each month; 6 June (Subject Great Lumley IGLARErEC)- Alternate Wednesdays, 7.30pm. Great Lumley Community Centre. RAE and morse tuition if required. Sec to be arranged), 7.30pm. Visitors welcome but must first contact Simon Garrett, G4EVN, PO Research Centre, Martlesham Heath, Ipswich. G4D WM. Hartlepool (H AC) - Mondays, 7.30pm. Methodist Church Hall, Grange Norwich (Norfolk ARC) -Wednesdays, 7.45pm. Crome Community Centre, Telegraph Lane East, Norwich. Details from Peter Forster, Road. Sec G3N WU. G3V W0. Middlesbrough (Post Office ARC)-All amateurs welcome, but first Southend (SErDRS)- Fortnightly, 8pm. Church Hall, Sir Walter contact sec G8CDP. Rayleigh Drive, Essex. Contact sec G3Y0A. Middlesbrough (Teesside Repeater Group) - Last Tuesday in each Stow market (SErDARS)- First Monday in each month. 7.30pm. Red month, 7.30pm. 196 Marton Road, Middlesbrough, C(eveland. All Cross Hall, Stowmarket Railway Station. Details from Ray Preston, amateurs and swls invited but first contact sec G8MBK. G8MYE. Morpeth (Northumbria RC)-Thursdays (Informal). "Queens Head", Thurrock (TARC) - First and third Tuesdays in each month, 8pm. Morpeth. Sec G8GVN. Grays Park Hall, Orsett Road, Grays. Morse tuition available. Details Newcastle upon Tyne (Tyne Er Wear Repeater Group)-7.30pm. from sec G3KMD. Club net on 144MHz S21/22, on second and fourth Arts Common Room, Claremont Tower Block, Newcastle University. Tuesdays in each month, 8pm. New members and visitors welcome. Sec G4DOB, tel Newcastle 744444. Vange (VARS) -Thursdays. 8pm. Main Hall, Barstable Tenants' Corn- South Shields (SSErDRS)- Fridays, 7.30pm. Trinity House. Old and munity Association, Long Riding, Basildon. Details from Mrs D. Thomp- new members welcome. Sec G8BCIF, 67 Lauderdale Avenue. son, 10 Peering Row, Basildon SS14 1TE. Tyneside (TAS) - Mondays, 8pm. The Community Centre, Vine Street, Wallsend. Sec Alex Frazer, 35 Percy Street, Tynemouth.

REGION 17-RR (Post vacant) Basingstoke (BARC)- Third Wednesday in each month, 7.30pm. REGION 19-RR R. J. C. Broadbent, G3AAJ, 94 Herongate Road, Chineham House, Popley Way, Basingstoke. Wanstead Park, London E12 5EQ. Basingstoke (UK FM Group Southern) -First Wednesday in each Barking (BREtES)- Mondays (Constructional), Wednesdays (CCTV), month. Chineham House, Popley, Basingstoke. Details from pro Chris Thursdays (Informal), 8pm. Tuesdays (Morse classes), 7.30pm. 17 May Jackson, G8P0B, 69 Buriton Road, Harestock, Winchester. (Film show). Hon sec A. Sammons, GBIZN. All welcome. This group is Bournemouth (Wessex ARG)- Bournemouth School, East Way, once again looking forward to the Dagenham Town Show, in July, and Bournemouth. the new, improved, beer tent. Chippenham (CErDARC)- Tuesdays, 7.30pm. Liberal Club, 20 Cheshunt (CEtORC)- Wednesdays. Church Room, Church Lane, Gladstone Road, Chippenham (temporary premises). Sec P. J. Tuck. Wormley, Herts. Hon sec G30JI. Fareham (F&DARC)- First and third Wednesdays in each month, Chingford (Silverthorn RC) - Fridays, 7.30pm. Friday Hill House, Sim- 7.30pm. Porchester Community Centre, Room 9. Sec David James, monds Lane, Chingford E4. Sec G4AJA. tel 01-529 2282. All visitors G8GRV, tel Titchfield 1032941 45977. welcome. Farnborough (FErDRS) -Second and fourth Wednesdays in each Chiswick (Acton. Brantford Et Chiswick RC)- 15 May (General month, 7.30pm. Railway Enthusiasts' Club, Access Road, off Hawley discussion), 19 June (Members' interesting QS0s), 7.30pm. Chiswick Lane, Farnborough. Sec G3TMO, 103 Hawley Lane, Farnborough. Trades and Social Club, 65 High Road, Chiswick W4. Hon sec G3GEH, Guernsey (GARS)-Tuesdays and Fridays, 8pm. Details from sec tel 01-992 3778. GU8ITE, PO Box 100, St Peter Port, Guernsey. Ealing (E&DARS)- Tuesdays, 8pm. Northfields Community Centre, Horndean (H&DARC)-Second Thursday in each month, 7.30pm. Northfields Road, W13. Sec G8KPN, tel 01-997 5949. All welcome. Merchiston Hall, Horndean. Net Sundays, 6.30pm, 21.40MHz, Sec East London (ELRSGBG)- 20 May ("More about sstv" by G4CJQ); G4CHO. The group will then close for meetings until the third Sunday in Jersey (JARS)-Sundays, 10.30am, and Fridays, 8pm. Le Hocq September. A full lecture programme is being compiled and members Tower, St Clement, Jersey. Sec R. H. Ford, "Sanaldi House", Plat may obtain details from the new hon sec J. R. Holmes, G3PKG1. tel Douet Road, Bagot, St Saviour, tel 0534 31131. 01-558 2928 (home). Poole (PARS)- Last Friday in each month, 7.30pm. Poole Technical Edgware (ESORS)- Second and fourth Thursdays in each month, College. Sec J. Worth, G3ZKA. 8pm. Watling Community Centre, 145 Orange Hill Road, Burnt Oak, Portsdown Hill Repeater Group-Activity night on GEI3PH (RB2), Edgware. Programme includes regular morse code practice classes. Sec Mondays, 1930gmt. All stations welcome to the net. Details from G3MNO, tel 01-907 1237. Monday evening net 2150 local on 1.875MHz. G8GNB. Harrow (FISH) - Fridays, 8pm. Harrow Arts Centre, High Road, Har- Portsmouth iP&DRC) - Wednesdays, 7.30pm. Portsmouth Com- row Weald. (Bar, car park -park neatly.) Hon sec G4AUF. tel 01-8e3 munity Centre, Malins Road, Buckland, Portsmouth. Sec G3CNO. 5002. Salisbury (SRErES) -Tuesdays, 7.30pm. Salisbury Activity Centre, Havering I HE/DARC) - Wednesdays, 8pm. Fairkytes Art Centre, Billet Wilton Road. Sec G2FIX. Lane, Hornchurch (opposite New Queens Theatre). Details from A. G. Southampton University (SUARCI-Tuesday evenings. Also infor- Negus, G8D0J, tel Upminster 24059. mal meetings every lunchtime in the clubroom, Old Union Building. Sec Holloway (Grafton RSI-Fridays, 8pm. Holloway Institute, Archway A. C. Talbot, The Radio Club, JCR Post, The University, Southampton. Annexe, Highgate Hill, London N19. Details from sec B. Bond. G3ZKE.

RADIO CO M MUNICATION May 1979 459 Ilford (IRSGBG) -All meetings are informal. 50 Mortlake Road, Ilford, Essex. Sec. G3LRE, tel 01-500 7196. London EC2 (Post Office HO ARGI - Wednesdays, 6pm. Room 413, "Lutyens House", Finsbury Circus, London EC2. Chairman G8EUO, Room 28, Euston Tower, tel 01-388 11 es ext 323 Idayl. Northolt (British Airways European Division ARS)-First Monday in each month. Trident Club, Western Avenue, Northolt, Middlesex. This club is open to non-BA employees by invitation. Contact G3TLG for details. Civil Aviation Sunday net 1100-1200gmt on 3-68MHz, listen for G3NAF or G3BEA. (Will sec please contact RR19.1 St Albans (Verulam AR M - Fourth Thursday in each month; 24 May ("Microphones' • by A. Bitton), 28 June ("Antenna for 144 and 432MHz" by B. Howlett, G3JAMI, 7.30pm. Hon sec G8MAE, tel 0442 64751. Meeting venue was due to be altered at time of going to press, so members and prospective members should check with hon sec before visit. Shelburne (SRC) - Wednesdays and Thursdays, 7pm. Shelburne Youth Centre, Hornsey Road, London N4. (Club members: Please ask your sec to send programme details to RR19 if you wish this entry to G3BCC operating the Yeovil Amateur Radio Club station G3C MH continue- RR19.) to com memorate the 25th anniversary, on 21 February, of the first Southgate (SRC) - Second Thursday in each month; 10 May ("Spec- long-distance short-wave contact in Britain using a transistor trum analysis" by B. Curant of Tektronix Ltd), 7 June (Working models transmitter. The ORP transmitter is on the right, and the best and slide show of vintage wireless equipment by T. Constable of BVVV distance worked with 38m W was G3EUE at 116 miles. The GAP Society-should be well worth the extra effort to visit RR1.91, 7.45pm. station is operational on 3.549MHz on Thursdays at 1945bst. The Scout Hut, Wilson Street, Winchmore Hill N21. Sec J. Fitch, Photo: B. F. Hillard G8EWG, tel 01-440 7353. All welcome. South Kensington (Baden Powell House Scout ARSI - Third Tues- day in each month, 6pm. Baden Powell House, Queensgate, South Ken- Gloucester (GARS)- First and third Thursdays in each month, sington. IRR19 has not received any communication from this group 7.30pm. Chequers Bridge Centre, Painswich Road, Gloucester. Hon sec since February 1978. If this club is still in existence would any RSGB G3MA. members who attend meetings please telephone RR19- R R 19.1 Weston-super-Mare (WsMARS) -Second Monday in each month South West Herts UHF Group- This group, currently running (except August), 7.30pm. Lewis Block, Worle Comprehensive School, GB3HR, requires donations; to G3THO please. The building of GB3BM Redwing Drive, off Mead Vale, Weston•super-Mare. Hon sec Irvin Barr- and GB3S W M, the 10GHz beacon, is currently progressing. Talks can Sim, "The Old Dairy", Eastertown, Lympsham, Somerset. be arranged for interested clubs. Sec G888E. Yate (YEtDARC)- First Friday in each month, Etprn. G3RQN 0TH. Fur. Stevenage (S&DARS)-First and third Thursdays in each month; 10 ther details from G8LGC. All welcome including swls. Local chat chan- May (DF hunt on 144MHz -start at Fairlands Valley car park), 17 May nel S24, 2100 Wednesdays and Saturdays. ("Guide dog training" by GBFOY I, 7 June ("Getting started on 1 • 3GFIz" Yeovil (YEPDARCI-Thursdays. Building 101, Houndstone Camp, by G8DKK), 21 June ("Top band df rx" by G4DDX), 5 July (AMSAT Yeovil (off A3088). Hon sec G3NOF. Club net 10.30am Sundays, Phase 3 satellite information meeting -prov), 8pm. Morse 7.30-8pm. 3 • 660M Hz . RAE courses are being run by G3SJFI and G8HTC. B. A. Dynamics Ltd, Plant 8, Staff Canteen. Details from sec T, J. Tugwell, G8KMV, tel 0438 54689. FM net, Mondays 1930 on 145• 550MHz. UK FM Group (Londonl- Second Tuesday in each month, 8pm. "The Green Man", near Great Portland Street underground (easy parking). Hon sec R. Street, G3TJA, tel 01-998 2672. All welcome. West Drayton (LT District Line ARC) - Thursdays, 6pm. DLAA Radio Com munication Handbook Sports Ground, Park Place, Gunnersbury Avenue W3. (Bar). This club requires the attendance of former members, who lost interest, to enable (5th edn) the club to survive. It would also like the assistance of local amateurs who could give talks on any radio topic. Hon sec R. Ball, G8JEB, tel First published in 1938, and a favourite ever since, this large and 01-422 0414. Club net 144• 250 ssb, 2000-2100 local. comprehensive guide to the theory and practice of amateur radio takes the reader from first principles right through to such Contrary to popular belief your RR does read every bit of all club specialized fields as radio teleprinters, slow-scan television and newsletters he receives, but it is surprising how many do not put in the amateur satellite communication. forthcoming programme-there is generally a lot about history and past Chapter titles: events (editors/secs please note). G3AAJ is also running a private com- Volume 1: Principles; Electronic tubes and valves; Semicon- petition for the best laidout details for this feature which arrive in time ductors; HF receivers; VHF and uhf receivers; HF transmitters; for compiling. To date, Chiswick, Southgate and Verulam are running VHF and uhf transmitters; Keying and break-in; Modulation neck and neck -RR19. systems; RTTY. Volume 2: Propagation; HF aerials; VHF and uhf aerials; Mobile and portable equipment; Noise; Power supplies,* Interference; Measurements; Operating technique and station layout; Amateur satellite communication; Image communication; The RSGB and the radio amateur; General data. REGION 20-RR G. Mather, G3GKA, 8 Hills Close, Keynsham, "These volumes should be well worth the expense to an Bristol. amateur who is interested in the technical aspects of the Bridgwater (HPSSARSI -Second Monday in each month, 7.30pm. pastime. - - OST (American Radio Relay League). YMCA, Nr St John Ambulance Hall. Further details from G4ETN. "The high standard evident in Volume 1 is fully maintained in Bristol (BARC) - Tuesdays, 7.30pm. The University Settlement, Bar- Volume 2 and, together, they contain a wealth of information for ton Hill, Bristol 5. Sec G8KGE. the serious amateur. Highly recom mended"- Electronics Bristol (BRSGBGI - 7-9.30pm. Small Lecture Theatre, Queens Australia. Buildings, University Walk, Clifton, Bristol 8. Hon sec G4FRG. Bristol !North Bristol ARC)- Fridays, 7pm. RAE instruction Volume 1:480 pages £9.36 incl p&p Wednesdays, 7pm. Lockleaze Community Association, Romney Volume 2:336 pages £8.12 incl p&p Avenue, Lockleaze, Bristol BS7. Hon sec G2BSU. Bristol (Shirehampton ARC)- Fridays, 7pm. Twyford House, Shirehampton. Hon sec G4GTD. HF and vhf station all modes, lectures and films, df hunts etc, planned for 1979. RAE and more classes in pro- Obtainable fro m gress. New members welcome. RSG B Publications (Sales) Cheltenham (CARA)- First Thursday and third Friday in each month. "The Old Bakery", Chester Walk, Cheltenham. Hon sec G8MZV.

RA DIO CO M MUNICA TION May 1979 TA33Jr, in use only one year, vgc, £60 ono. Buyer collect. HW32, ac psu, hb dc psu, all in wkg cond, £70 ono. G3U0B, QTHR. Tel 01-670 ,re 4228. members' ads 2200GX, good cond, stab psu/charger, mounting bracket, £140 ono. Microwave Modules 2m converter, 28-30 i.f., £12 ono. 70cm converter, 28-30 if,, £14 ono. STE Melan if, board, 2B-30MHz, S-meter, £35 ono. A. Pearce, G8MAN, QTHR. Tel Bolton 40164, after 6pm. QRT clearance: Ringo Ranger ARX2 colinear, boxed, instructions, 9ft by 1.6n steel mounting pole, both enamelled, in exc cond, £20. Pairs of These subsidized flat-rate advertisements are accepted as a service to new unused 6in wall mounting brackets and 12in chimney lashing kits members of the ASGO. They must be submitted on the Members Ads for above, £5. 80f5 UR67, good cond 150ft new and unused), £7.50. order form printed in alternate issues of Radio Communication, or on a SWR200 swr/pwr meter, used very little, etc cond, orig packing, postcard similarly laid out. Each must be accompanied by a recent instructions, £15. GBMEN, OTRA. Tel 01-733 t.:78. Radio Communication mailing label addressed to the advertiser, as proof Trio 2200GX, as new, extras, orig packing, £130. EC10 Mk2, mains psu. of membership, and a remittance by postal order or cheque for 75p Wanted: FT101, approx £360. G8CDP, QTHR. Tel 0609 2068, office hours. (stamps not accepted) for every 40 words or part thereof. They will not be acknowledged. Those not clearly worded or punctuated will be Wavemeter, class D, No 1 Mk2, mains psu, handbook, spare valve, £10. Heath HR1OB 10-83m rx, vgc, £93 ono. Furzehill 400Hz electronic returned. No correspondence concerning this service can be entered tuning fork, 16V dc, £5. Manual for HW101, offers. Transistor Multiplex into. stereo decoder, info 12V dc, £3. Shaw, 16 Deansfield, Four Spires, Cricklade, Wilts SN6 GOP. Closing dates in 1979; 28 May, 21 June, 2 Aug, 30 Aug, 27 Sept, Ayo electronic test meter, £20. Chart recorder, £10. Transverter, 25 Oct, 22 Nov, 27 Dec. No guarantee of inclusion in a specific issue 7-1 -8MHz, as AR AL Handbook 1970, with handbook, £25. Radio Com- can be given, other than the first possible issue after receipt. munication, '61-69, £10. 30 books on radio/electronics, incl Terman, Langford Smith cathode ray, Scroggie, £25. G3K WK, OTRA. Tel Red- Trade or business advertisements, even from members, will not be ditch 41502. accepted for Members' Ads but should be submitted as classified or Trio 2200GX, 12ch, all repeaters, two simplex, antenna broken, no display advertisements in the usual way. Traders who are members must mods, £60. 2m fm pa, 1W in 2W out, preamp, £10. Pye Pocketfones, ta enclose a signed declaration that the items for sale or wanted are part of, a nd rx stalled on R814, batts, £15. Knowles, G4FPN. Tel 021-745 1363. or intended for, their own personal amateur station. Pye Pocketfone PF1, xtalled RB10, toneburst, nicads. £30; Datong The RSGB reserves she right to refuse advertisements, and accepts clipper module, in die cast box, wired for 444 mic, £30; all ono. Prefer no responsibility for errors or omissions or for the quality of goods of- buyer collects or plus post. G8JGK, OTHR. Tel 0245 69034. fered for sale. Advertisements may be edited or abbreviated as F17, six months old, used little, in orig canon, accessories as supplied, necessary. £260, no offers. G3TMT, 21a Pelham Road, Lindfield, Haywards Heath, Advertisements for 27MHz equipment will not be accepted. W Sussex R H16 2EW. Lafayette KT340, bandspread on amateur bands, vgc, £25 ono. BC342 rx, modern front end, £20 ono. Eagle 30W pa amplifier, wkg, o/p valves Post to: ME MBERS' ADS. RSGB, 88 BROOMFIELD ROAD, missing, £5. Ferguson 3272 cassette deck, vgc, £55 ono. PSU, 200-400V CHELMSFORD, ESSEX CM1 1SS. stab. + 200--900V unstab, + 6.3 at 8A, rack, £20 ono. Tel Peter, Aylesbury 26811. Do not post to ASGO Ha or Advertising Representative TR7200G.exc cond, auto tone, orig packing, manual, fitted SO, S18-24, R3- 7, R4 input, R7 full reverse, incl AS P2009 5/8 3dB whip, "no hole" mount. £140. G8DAQ, QTHR. Tel Medway (0634) 576758. TR7010 2m tab tx/rx, as new, one owner, 5/8 whip, £135. G3ZVC 9MHz tab taira, KVG XF-9b filter, kit constructed on commercial pcb. G3OLX, QTHR. Tel Burgh Heath 55271. TS820, as new, £605; JR500S 160-10m rx, £60; FROX400, 160-10-6-2m, FOR SALE seven filters, etc, £170; IC2OXT, 10W/1 W, RO, R5-7, S20-22, £90; all with handbooks. G3XYT. Tel 021-354 1566. Zygi beam, 20m, 3-el, per Radio Communication October '75, precision Back issues, must sell as clearing out shack: Radio Communication construction, works well, as new cond, £45 ono. G4HXQ NOT QTHR. May'76 to December'78; S W M '75 and '76; TV '72 and '78; 20p ea plus Tel Clavering (Essex> 433, after 7pm. sae; also P W, PE, EE, RC. Robin Bayley, 8 Field Lane, Kemberton, Shif- F7101E, as new, cw filter, spare drivers and pas, dust cover, manual, nal, Salop. multi-mobile antenna, 80, 20, 15, 10, plus base and bag, sale on behalf Microwave Modules 23cm converter, 144MHz if., brand-new, of G3YPK (F0DXLI, £450. G8DAQ, QTHR. Tel Medway (06341 576758. unused, £22. VBC98C varactor diode, 13W out on 70cm, unused, £3. Swan 350C taira, vgc, £325; Ayo 8 Mk3. £40; Avo transistor analyser, Sentinel low noise 2m preamp, £6. Stereo headphone amplifier, £12. £20; Avo test set, £10; Wier dvm, £25; Heath DX4OU lx, £25; all comp QC)V03/20A, good, £1.50. G8JWC. Tel Leamington Spa (0926) with manuals. Wanted: FT101B/ E; part etch? G4HLM. Tel Tony, 01-952 26681, after 5pm. 0665, after 6pm. Minitennas. C4, 10, 15, 20, coaxial, vertical, unused, comp, £32. Buyer Swan 500 tx/rx, etc cond, 80 10, 450W pep., comp with ac/dc power collects. G3CDC, QTHR. supply, manual, etc, £250. G3YFG, OTHR. Tel 0254 82 3769. evenings. Data rec/reprod,1¡ to 120in is, seven ranges data, in/out interface, r/c FT200, FP200, all 10m xtals, mint, £250. G3NKL, QTHR. Tel Longridge 8-track 0.5 by 10 -Sn reels, vacuum transp, in 6ft cabinet, best offer over 2511. E100 secures. Buyer collects. G8DXC, QTHR. Tel 0353 860646, even- FT221RD/VC221, few months old, boxed, as new, £50 off list price, ings. genuine sale. G8KOP. QTHR. Tel Dave, 01-349 1122, days. MB M88, £15. Sinclair Scientific, £7.50. 3cm wavemeter, £8. CCTV IC215, in box, as new, leather case, SO, S18--24, S32, R5-7. RR5, £145 camera, optical focus, £50. WG16, £1 per ft. G8JAI, OTRA. ono. G8RJQ, 79 Victoria Road, Cowes, IOW. Tel Mike, Cowes 295943. Heathkit HW12 single-band ssb tx/rx for 80m, two new pa valves, ideal Pye Cambridge FM10D, low band, one boot mount, c/w remote con- mobile or beginner's rig, £65. 12V de psu for same, £10. Collec- trol, etc, part modified to 2m, spare output valves, one hand portable, tion/delivery by arrangement. G3YKP, NOT QTHR. Tel Coalville 38995, unmodified, internal control l/spkr, etc, handbook, the lot, £40 ono. any time. G8FMH, QTHR. Tel Basingstoke 23979. TR7200G, 22ch, nine repeaters, 13 simplex, main psu PS5, digital clock SSR100, used little, very good rx. £120. G3REO, QTHR. Tel Coniston and time switch, used little, comp, £240 ono. G3OUX, QTHR. Tel 0293 329. 23890, after 5pm. 70cm-10m converter, QM70, re-aligned by maker August'78, receipted 2m Pye AM10B, vgc, 11ch, fitted 9ch, plus two 144MHz ta xtals, invoice sent with converter, £11. G3VCJ, 0TH)'). preamp, switched a.m./fm and toneburst, handbook, circuit, spare pa, Yaesu FRDX400, all options. FLDX400, manuals, one owner, perfect, £60. 12V hid battery to suit, vgc, £15. G8PEG, QTHR (near NEC). Tel YD844 mic, set of spare valves, £325. G3JON, QTHR. Tel Sheffield Knowle 105645) 78218, any time. 367774; or 732333, daytime. TA33Jr tribander, £45 ono. 30ft Hamtower, comp with top plate, £50 Creed 7B, £10, Plus loads of gear: components, incl video at give away ono. Buyers collect. G40(18, GTHR. prices, brand-new transistors, at 5p ea; 8 by 5in 15 and ea spkrs, ven/ Standard C826, 2m, fm, 10W, 12ch, 8ch fitted, SO, S20-22, R5-7, RR5, cheap. Callers collect something free. Wright, G3HRN, 18 Granville handbook, mobile mount, £110 ono. C,3TDJ, QTHR. Tel Bude 102881 Avenue, Newport, Shropshire. Tel 811168, anytime. 3701.

RADIO CO M MUNICA TION May 1979 461 Labgear LG50 tx, a.m./ow. 10-80m, £15. Joystick antenna, Joymatch, Fil. £49. DeWald TR850 50MHz Dr/ rx, W/50• 5 xtal. €25. TA33Jr beam, £20. Eddystone mech bug key, £10. Yaesu YH55 h!phones, boxed, collect, EEO. Boomless quad spider, £10. 4X1504, £10. 5V CT, 14- 54 new, £7. Tandy cassette morse course, C2. Part delivery extra all items. 120V ac, £10. Knight R100 rx, manual, 120V ac, £25. 100pF, 7kV G4HBU, QTHR. Tel Bristol (0272) 611093; or 551055. variable, £5. FT243 xtals. 3561-5, 3562• 5. 3564, 3609, 3609- 1, 3613-7, 125G7, 12K8, 12SK7, 12SR7, 20p ea. Unused ECF82, 6BE6, ECC8I, 3634-4, 3657-8, 3658. 3662. 3784, 3797-4, 7042, 8175, 5675, 5677• 7, ECC83, EL84, EF93, 042, 6CX8, all 50p ea. Unused KW204 vox unit, 5775, 13,100, 80p ea. R. Guard. Oaker Bank, Skipton Road, Killinghall, £12. 1-pole 6-way ceramic switch, £3.50. G4GHB, QTHR. Harrogate HG3 2AR. 300W p.e.p. Output hb hf linear, self-contained psu, TT21s in AB1, £50. Synthesized 2m mobile, Kyokuto digital 2. plus SEM 48W Berco Regavolt 84 0-260V autotransformer, £15. Min 2m super-regen power/preamp unit, £230. G8B2N, QTHR, Tel 0455 35E21. hb rx, £4. Wanted: urgently, Trio R5S9S rx, your price. G3XZV. Tel Har- FT221R, in fine cond, used little since purchased new, £275. Buyer col- rogate 862147. lects. G8NIW. Tel 01-651 3363. Holiday hotel, 100yd Blackpool cliffs and promenade, comp shack, 60ft Standard C82BM 2m 10W tx/rx, 12ch xtalled, t/b, CV110 vfo, match- tower, 2-el 40m and 4-el 10m Yagis, 160 dipole, ideal location, 11 ing spkr, manuals, £175. Standard C430 70cm 10W tx/rx, I2ch, t/b, bedrooms, sun and tv lounges, licensed. G3TSL, "Bryn-Garth" Private manual, £150. Standard C1464 2m 2W hand-held tx/rx, tib, case, Hotel, Shaftesbury Avenue, Blackpool. Tel 52453. charger, nicads, flexi antenna, manual, Base Master, E125. G3YMS, Pye Cambridge FM10P, preamp, toneburst, manual, nicad charger, QTHR. spare quickheats, set up on SO, S20 22, R6, £66. Wanted: KW2000, or Trio TS700G, S0306 preamp, exc cond, orig packing, prefer buyer col- similar, must be good cond. McKee. Tel 051-652 1309. lects. £350 ono. G4FAB. QTHR. Tel Wigan (0942) 31675, after 5pm. Dentron MT3000A tuner, £220. FDK2700 Mk2, multimode, £390. FR1015, 10 , 160, all bc bands, mint, used few hours only, will deliver Sistate linear, 80VV, 670. Daiwa remote masthead antenna switch, vhf reasonable distance, £400. G4HBP, "Ploughman's Piece", Thornham, preamp, £25. Vibroplex Deluxe, c/case, £25. Hansen vhf pwr/swr Norfolk. Tel 322. bridge, £20. Two 4-el 2m quads, £10 ea. Shure 5261 desk mic, preamp. Assembled Mosley RD-6 receiving trap dipole, 10-80m, with feeder. IC215, 15ch, plus RR6, type C nicads, charger, carrying case, helical £15. Heathkit Superes headphones, model GD396, high impedance, £3. whip plus telescopic, £145. Y0100 Yaesu monitorscope, £95. SP101B G8JBK, QTHR. Tel Grays Thurrock 70074. Yaesu spkr, £10. Xtal filter, 1-4MHz, carrixtals, £6. SSI3/cw modules, Racal RA17L, mint cond, case, handbook, £200. GBAZU, QTHR. Tel 1-4MHz if., data manual, £10. GM3XNE, QTHR. Sunbury 89036. M15 teleprinter, reader, £15. 500/0/500V, 0 • 54 stab psu, £20. Marconi Dynamco 0.01% dvm 2006. offers; Seiko R P101 drum printer, £25; Ayo TF39 sig gen, 18/103MHz, very accurate output, £8. Two 4CX250Bs, £6 model 8, c/w leads, £18; Telequipment 053 oscilloscope, 05; Level) pair. Maritime CR100 (no mods), £20. Many 10GHz and vintage com- oscillator, £35; 2A cased variac, £8. postage extra; consider exch lcash ponents, sae GBIPY, QTHR. Tel 01-977 19E12. adjustment) for gc rx. Tel Asthall Leigh (Oxford) 220. CR100 rx, £15. G8MPX, 96 Broadlands, Hillyfield, Walthamstow, Lon- FT221 R all modes 144-148 tx/rx, as new, hardly used, fully synthesized, don E17 6DF. £20. Sailor RT142 vhf marine tx/rx, latest GPO spec, 16 xtal channels, DX160 rx, £60. Collect. Wanted: Heath RAI rx. Roberts, 71 Gibbins £300. Brock. Tel Oxted 2141, evenings. Road, Selly Oak, Birmingham. EC10 Mk2 rx, £85. TM55E1 vhf scan rx, fitted 10ch, SO, S20, S23, R3, G2DAF tx, XF9B, psu. professionally sprayed, engraved, £60 ono. ZVC R7, supply 12V, 230V, 675. R010 Q-multiplier, £7; PR30 preselector, £7; 9MHz ssb board, XF9B, rf amp, preselector, predriver board for six hf or £12 the two. All ono, collect or carr extra. G8SBU. Tel Fareham bands, 6V, 12V stab psu board, Vackar vfo die-cast box, reduction 232799, after 6pm. drive, £65 ono. G3X2V. Tel Harrogate 8E2147. Trio 16520, ow filter, SP520, MC10, £433. KW105, modified to 107 Trio TFL2_200G, fitted 12ch, illuminated dial and meter, auto toneburst, spec, £65. 18AVT/WB, £45. Datong rf clipper, £28. Twin meter comp with nicads, charger, etc, £120 ono. Convergence board for BRC SWR504, £6. PBM18/70. £10. 052100 35MHz oscilloscope, £250. 2000, new, offers. G810(M, QTHR. Tel 0782 535316, after 7pm. G4FMD, QTHR. Tel 0371 3119. Trio JR599 Tx, all filters, £150. KW Viceroy Mk3A tx, 6146Bs, mic, £65. Trio JR500S. ham bands only, no mods, works well, stable, manual, Decca/S MC rnonitorscope, brand-new, £65. Heathkit sig gen RF -1U, £55. Tel Coventry 22201, after 6pm. £15. KW160 a.m./cw tx, £16. Tech Assoc speech comp, £12. Callers FRG7 gen purpose comm rx, fitted fm discriminator in place of noise only. Pryse, 36 Hart Road, Byfleet, Surrey. blanker, rx ego, just one yl owner who is now licensed and wishes to Micro memories: a few 1702A U/V erasable proms (8 x 512), £3 ea; sell, comp with Microwave Modules 28/144 vhf converter, £150 or Creed 7B, 240V ac, £18; Bantam HPIFM, 145.0, R6, xtal/vfo on rx, nearest offer. Tel Aberdeen 24715. case, nicad, £40; 50W valve linear amp, £5. Smith, G8DVN. Tel (home) Heath HW202 tx/rx, toneburst. HW2036 ac psu, prof built, mint, with 0E23 882174, (work) 0777 706777 ext 9. xtals Sb, S12, S14, 516, 520 23, RO, 133, R5 6, manuals, £150 ono. Tel Moving sale: Heathkit SB230 conduction-cooled linear, £280; Trio Denis, Kidderminster 66311 ext 58, 1300• 1900gmt Tues- Thurs. 1S820, remote vfo, ow filter, £675; Hy-Gain TH3 Mk3 triband beam, Creed 444, 45 bauds, £50. Delivery to Harrow possible. Wanted: 70cm CDR Ham-M rotator, cable, £220. C. Kratzer, G5CAA, 8 Fairholt Street, gear, incl tx/rx, linear amp, high gain antenna. GW8416, QTHR. Tel London SW7. Tel 01-589 1816. Caersws 288. HC25/U 48MHz xtals for following 2m channels, RO, R4 7, S22, £1.50 Exch: 22030X, mint, fitted nicads, SO, S18, S20- 21, R2 simplex, 114, ea. G8FDJ, 15 Bakehouse Road, Honey, Surrey. RH6 8MQ. Tel 74969, R6-7, plus charger; for pocket 2m tx/rx, or hf linear; or sell for £120. evenings. Oscilloscope, VVM8, £35. G4GOL, QTHR. Tel 01-518 1562. TX/RX. Bosch, 2m, 520 -22, R5, 0 -5W. £35. QQV06-404 pa, tuned' Shack clearance: KW2C00 dc psu, offers; 807s, 6V6GTs, VR105/30s, lines, blower, rf change-over and power supply, £20. Marconi sig gen, 6146s, VR150, 50p ea; fixed and variable resistors and capacitors; valve 10-150MHz, £18. GEUZO, QTHR, Tel Reading (07341 51592. bases; transistors; diodes; 40763s; various bits. GW3YTL, QTHR. Tel Trio TS520, ow filter, VFC/520. MC50, heavy-duty mobile leads, £450. Knighton (Powys) 528030, evenings. G3VVTM, 46 Naseby, Hanwonh, Bracknell, Berks RG12 4HD. KW monitorscope, exc cond, handbook, £60. GW4GNY, QTHR. TR7200G, channels RI-7 fitted, incl mobile mount, handbook, orig Combined gdo absorption w/meter sig gen, 1-7-180MHz, mains input, packing, all in good wkg order, £95. Carr extra. Tel 0733 63851. £8; five PL509s, with valve holders, £2; solid-state audio amp, KlOm W, SB104A, fitted SBA104-1 noise blanker, HP1144 psu, £550; TR7500, £1; all plus carr. G3814, QTHR. Tel 01-977 6705. £175: both immac. G3000, CITHR. Tel Warrington 50177, daytime. PF1 tx board, xtalled on RB2, mic insert, £8. AX xtal for RB2, suit PF1 FRG7000 rx, digital, almost new, manual, £285. Sony CRF509) earth rx. £1.50. IF xtal PF I, £1.50. Parts for PFI rx: rf head, 50p; xtal filter, £1; orbiter, almost new, £140. Stephens James Mk2 atu, unused, £18. loudspeaker, 50p. G4AN W, 16 Chestnut Drive, Broadstairs, Kent. Owner emigrating. Buyer collects. Tel 0926 54152. F1221 R, late model, as new, fitted preamp, accessories, manual, £290; HF rx, professional performance, amateur bands, 3- 5 -30MHz, film scale or exch 'corn 202/215, cash adjustment. Technical Associates speech driven linear pto. KVG, ssb and cw filters, £160. Morse typewriter, processor, £15. 656 tape reader, new, £10. G8NPM, QTHR. Tel 64-character buffer fifo, variable speed and weight, £100. SAE or tel for Wickford (Essex) 4317, evenings/weekends. details. G3URX, QTHR. Tel Cambridge (0223) 312827. TR2300, nicads, £150; Microwave Modules 5CX)MHz counter, £49; KW2000A, ac and dc psus, assorted spares, incl four pas, Compact Datong rf clipper, £35; QM70 2m cony, 28-30MHz, £10; vhf swr/pwr 300W linear, 18AVT, £325. TR7200G, SO, S20-22, R6-7, 6125. SSM 2m meter, €15; ht swr/pwr meter, £6; all mint cond, unused, boxed. converter, 28-30, £13. Prefer collect. Gulliver, GW4EDQ, 30 Highbury G4BKM, OTHR. Tel 01-568 8497, or Denham 4358. Crescent, Cefn Glas, Bridgend CF3I 4110. FR508 rx, 160-10m, calibrator, £60. HRO rx, bandspread coils, £25. Trio 5R59D, £30. 5FP7, £4. 713R7, £5. VDU, 80 x 13 display, Baudot 1 Heathkit ham bands rx, 80-10m, £20. Wanted: KW E-Zee match, vtvm ASCII, £200. Cheap ttl etc: eg 7490, 26p; 7475, 35p; 7400, 11p; 74121, with probes, G2DAF rx, Datong audio filter, EA12 rx, 2m tx/rx. Wright, 23p; 741, 14p; all new. SAE for full list. G8DJM, QTHR. Tel Lye (0384821 67 Berwyn Close, Buckskin, Basingstoke. Tel Basingstoke 68649. 43E8. Versatower, 58f-t post-mounting crank-up type, with winch, 20ft when 3cm Gunnplexer tx/rx, as reviewed Nov '78, unused, with mfr's test closed, £175. 14-el Parabeam, 2m, £24. B40 4m rx, £15. DX100, £60. R. report, £69 incl. G8APX. QTHR. Heaton, "Moberly Tower", Burlington Street, Manchester M15 6HR.

RA DIO CO M MU NICA TION May 1979 Drake DSR1, superb rx, solid-state, 10kHz-30MHz continuous, syn- TR2200GX, S20-24, R3, R6, RR3, RR6, nicads, helical antenna, £155. thesized, digital readout to 100Hz. a.m., ssb, cw, qty, isb, bandwidths ASPE29 mobile 2m antenna, incl magnetic mount, 122. Boom mic, foot 6-0.4kHz, 2W output, current price over £2,000, as new, manual, car- switch, £13. Carr by Securicor can be arranged. G. Simmons, G4D WV, toned, £695. East, G8PKD. Tel 01-486 8286. Room C302. Henry Price Building, Clarendon Road, Leeds. Collins mechanical filters: F455-FA- 15 1 .5kHz rtty, F455-Y-21 2.1 kHz Telequipment db 043 'scope, recently refurbished, in as new cond, ssb, both brand-new, £25 ea; three F455-F-05 500Hz cw, £12 ea; add £109. Datong speech processor, £20. Z-match /750 1pf/swr bridge/800 postage. G3EWZ, QTHR. Tel Chester 24763, evenings. dummy load, all in one 19 by 10in cabinet, £55. G3LCS. Tel 0908 31M79. Trio model JR5e9 custom special, immac cond, little used, with R) and Heathkit linear 58209, factory assembled, vgc, £250 ono. G6GL. 144MHz, £165. KW 3-way antenna selector, Harvard stereo head- QTHR. Tel 09276 5914. phones, JVC and Winthronics radio cassettes. L. D. Ireland, "Carnhell TE46 R/C analyser, £10. ARE8D gearbox, £5. 2m converters: 2 4, 4.6, Green", Camborne, Cornwall TR14 ONA. Tel Praze 236. 28- 30MHz, £10 ea. Starphone hb rf boards, ok 2m, £4. BCC69 lb learn IC202, used few hours only, comp with hila 12V reg psu, 5-el mobile, comp, £5. Cossor 1035 sb 'scope, £15. Carr extra above. Jaybeam ant, £120. Ferrograph series seven r/r stereo tape recorder, G8PXS, 18 Hawkins Road, Folkestone. Tel 76063. 117V 90Hz, c/w 240V transformer, £100. G3UUV, QTHR. Tel 0249 2703, Trio JR310, n/b/filter, OD ono; Trio 9R59DS, extras. £60 ono; Heathkit after 6pm. 10-102 'scope. £80 ono; BC2217 mains psu, charts, etc, £20 ono; all sec SB102 tx.'rx, S8600 psu, 5E3640 vfo, all vgc, £195. Collins filters 455kHz cond, offers accepted. Buyers collect or pay carr etc. Selling due to blw 2, 4, 8, 16kHz, sets of four, £25. Loose filters. £7.50. G3LEZ, illness. G8HVQ. OTHR. Tel Lytchett Minster 622314, after 6pm. QTHR. Tel Southend 107021 230489. FT227R, FP4 psu, near new. £190. DX100U, AR88D, £90. PF1s, RB14, TR2200, £45. Keyboard, £12. 12AVO, £12. Buyer to collect, G3RTE, £30. CD711S 'scope, £10. 2m 5/8, with mag mount, £5. Marconi stab QTHR. Tel Potters Bar 57309. psu, 200 400V, £5. G4HVK. Tel 021-392 4048. QR666, 170kHz- 30MHz, plus fm unit, £100. Belcom Liner 2, preamp, AT5. with mains unit, T28, Hamgear PM2A preamp, Codar PR30. handbook, mic, £103. Callers only. 30 Duchess Drive, Bridgnorth, G3DMQ. Tel Reading 581481, Salop. Yaesu FR101D. 160-10, and 2m, all modes, as new, Perspex cover, KW200013, ac psu, immac, comp service by KW January '79, £250; £395. MMT 144/29 transverter. used very little, £65. G4HTE. Tel Potters KW1000 1,2COW linear amplifier, perfect, £150; KW110 Q-multiplier, Bar 54905. £20; KW low pass filter. £20; or offers for the lot. Wanted: vhf gear. eg Heathkit 10 180 'scope 4.5MHz, 30mV/cm, 5in tube and probe, ac FT200. Europa. why? G4FRB. Tel Cirencester 5.409. coupled only, exc cond, £55. Burton, 7 Springhill Drive, Crofton, Brown Bros American twin paddle key and electronic keyer, relay, as Wakefield. Tel Wakefield 862597. new Cowl Gill rotator; exch for twin lens reflex camera, or 2-tin' 35mm Trio 2200G, fully stalled, incl all access, £110 ono. NR56 monitor rx, b.,w enlarger, or why photographic? G2BUC, 18 Chesterton Park, stalled R3, R5-7, plus vita. £45 ono. G8RJI. Tel Wormbridge (Hereford- Cirencester. Tel 2349. shire) 413. 60ft 3-section Versatower, needs replacement top section, ready for col- K W2000, acidc, psus, Medco low pass filter, £100. Joystick, Joymatch lection, cash and carry price, £150. Regency mobile converter, 80-10m, atu, modified, £15. Wanted: atu (Z-matchl; FT75, comp; all letters for use with mw car radio, £20. G2PU, QTHR. Tel 0223 870454. answered. Grieveson, G4GXU. 6 Spinney Bank, Kings Sutton, Banbury, Robot sstv 80A camera, 70B monitor; two cctv cameras; 70cm Oxon parabeam; 70cm colinear; 2ft 8-el crossed Yagi; Stolle rotator; AR22 IC215E, R3 -9, SO, S24, S20 22, as new, helical antenna, one year old, rotator; 70cm converter, 28MHz if.; 70cm varactor tripler; heath 0S2 £140 ono. QM70 Buccaneer transverter, one year old. 40W p.e.p., £50. 'scope. G4CEQ, QTHR. Tel Dovvnland 55908, evenings. SEM ht auto preamp. S0239 conn, six months old, £10. G8JGK, QTHR. IC210 2m fm te /re, vio, eral channels S20, SO, rev rep. handbook Tel 0245 139034. (English photo-copy). £190 ono. Labgear 160 twin top band a.m./cw Valves: few unused, 6BA6, 25p; 6BW6, £1.25; 05150/45. 30p; few 10W lx, ac and 12V dc psus, circuits, £25. Buyer collects. G3KJU. electro mech four digit counters, five for £1. Wanted: valves, 12A6, QTHR. Tel 63415, after 6pm. 12SA7, 12SK7, 12SC7; very good HRO, comp, will collect; TCS12 TR2200G, 9ch fitted, SO, S20 23, R3 4, f36 , 7, nicads, charger, orig handbook. Tel Bradbury 10782l 21169, evenings. packing, manual, etc, vgc, £110 ono. G8FGY, QTHR. Tel Lowestoft Collins 'S' line, 3251, 7551 separates, transceive capability, 80-10m, 61343, after 6pm. 100W, 230-110V transformer incl, exc performance, £550 ono. G2DAF Shack clearance: many individual items and components, some unob- hb linear, 80-10m, 2 >. 813 1. 7kV psu, legal limit with reliability, £50 ono. tainable today, eg RF27 /28 units, ceramic formers, various pcbs, G3KKB. QTHR. Tel 021-427 1305. chassis, valves, transformers, tel for further info. Roger Alban. Fujian 2000A direction finding re, as used on yachts and boats, all solid- GW3SPA. Tel Cardiff 102221 499022 ext 3156, weekdays only. state, used little, mint cond, five wavebands, incl marine vhf, null meter, Memory keyer. iambic mode electronic cw sender, with 2,048-bit bfo, df antenna, 12V, £13(1 G4AYV, memory, needs 240V ac /12V de, less paddle, £64. Tel Steve, 0494 H W101, mains psu, E160. HW32A, covers comp 20m, mains psu, £60. 41765. Heathkit 0S-2 'scope, £20. Large ver inductance for antenna systems, K W202 rx, mint cond, manual, £175. KW Vespa te, now i/p, with pis, £5. HVV202, mic, £40. Ten-Tec 3W, 15-40m rx/rx, £30. HVV7, £30. manual, mic, £95. Will separate. G4RDF, QTHR. Tel Romford 47998. G3ZRD, QTHR, Tel 01-650 5899. KEF, kit 2, stereo spkr kit, unused, not assembled, in orig packing, list Pye Ranger adapted fm transformers: 700V 215mA, 6-3V 2A, £4; price over £60. bargain, £35. G3UUV, QTHR. Tel 0249 2703, after 6pm. 600V CT 50mA, + 6.3 CT 600mA, 6-3V 300mA. £3: 220V 300mA. K W2000A and power pack, used very little, very good cond, with cir- + 25V 1A, + 6•3V 9A, £3; 22• 5V up to 4A, 12, Wanted: reasonable cuit, handbook £150. Buyer collects. G3JEN, QTHR. Tel Halstead teletype or teleprinter. Heath, 103 Pollards Oak Road, Oxted, Surrey. Tel (Essex) 2331. Dated 4503. AIM digit capacitor meter, auto ranging 1pF-200F, v/g, cost £100, £60; FT101E, 600Hz cw pas, on air less than 15h, immac cond, plugs, leads, logic probe, £10; Grundig Satellit 6860, 12 bands, b/spread, £60 ono; manual, orig box, about 15 months old, £500. G4GG W, QTHR, Tel 0296 10W stereo amp, b/new. E30; or swop all or part of above for uhf 70cm 623441. transvener, 2m linear amp, vhf freq meter, or prescaler 2-500MHz for FT227R, one year old, little used, mint, no mods, orig packing, £200. freq rooter. P. Turner. Tel 0842 61648, after 7pm. GM8O WX, QTHR, Tel Sr Andrews 77066 or 2066. evenings. Pye tv carnets, vidicon, remote focus/lens change, £13. BC221, charts, IC240, as new cond, still under guarantee, £160; would consider quality psu, £14. Xtal wavemeter, £2. SN76666, 50p. 25M colour tv, just works, hand portable in part exch; going non-mobile. G8PYO. Tel Erith 37710. £22. Time-switch. £3. Transistor uhf tuner. £1. Scan coils, 35p. Wanted: HW100, psu, matching case incl Z-match, £200. Prefer buyer inspects 69ft telescopic mast. G8ABO; QTHR. Tel 01-452 6724. and collects. G4DUF, QTHR, Tel Wormley (Surrey) 2104. LM14, £15. KW2000 dc psu, £20. Marconi sig gen. TF390F. covers Heath, SB200 linear amp, mint, £320 ono. Datong FL1 audio filter, mint, 150MHz, £20. Bridge, Belco Bla8, new, £20. Components for grd/grid £45 ono. G4EHE, QTHR. Tel 027 582 2725, linear; two 813s, tested, good, no chassis, £60. Radio Communication KVV2000 Ix /rx, ac psu, gc, £110. Prefer buyer collects. G3YNR, QTHR. '61 '77, SW M '61-'74, E2 per year. Buyer collects. G4CRM, QTHR. Tel Tel 0246 74603, after 6pm. 07014 52442. SWL selling: Jaybeam 2m 6-el quad. £12; M8 432MHz, 48-el, exc cond. Solartron CD71152 7MHz twin beam measuring 'scope, internal £12. Denis Taylor, 25 High Brow, Harborne. Birmingham. Tel 021-426 timebase xtal calibrator, manual, £50. Small American hi-fi amp, about 5271, after 6.30pm. 2 x 8W integral preamps, front trim panel missing, £10. G3TCU, QTHR. M MV1296 23cm varactor tripler. 30W, Microwave Modules, as new, Tel Guildford 65607. 125; Yaesu SP401 spkr unit, £10; Eddystone 730.-4 gen coy rx, variable FT101E, plus FV101 350Hz cw filter, mint, £495. Buyer collects. 03H VA, selectivity, xtal phasing, filter, etc, vgc, £120; various transformers, QTHR. Tel Tadley 6106. meters. chokes etc, sae list. G3CHC, QTHR. Tel 021-308 2512. All stn portable television rx, good wkg order, model 4661 Mar- Eddystone 680X gen cov re, sep 30 spkr, good cond, £45. L. J. Pink,. coniphone, would accept €5. R. Cuddington, ARS40W5, "Milton "Gilberts Cottage", Church Street, Farringdon, Nr Alton, Hants. Tel Lodge", Milton Bryan, Milton Keynes. Tisted 477.

RADIO CO M MUNICA TION May 1979 463 Phone and haggle: IC22A, IC215, IC202E, C146A, Beloom AMR217B TH3Jr or TA33Jr, for club use, limited funds, will collect reasonable scanning rx, Belcom AMR104H scanning rx. EDL144 linear, MEL202 distance. G4EYD, QTHR. Tel 021-475 2773, evenings. linear, Trio OR666, PF5UH Pocketfone, PF1 Pocketfone, Joystick Com mand rx BC454 or ARC-5 model, 3.0-6-0MHz, preferably comp antenna; all fb cond, little used. G8MXE. Tel Holsworthy 10409) 253550. but can be without psu, send details. G3KZU, QTHR. Tel 08E6 63000. day time. evenings. A Ft88 hf rx, manual, spkr, in good cond, cash offers; or each for 2m or KW107 or 109 Supermatch. Speech compressor for FT101. GM6FP, 70cm hand-held rig. G41-1DI. NOT OTHR. Tel 048483 7656 (West Yorks). QTHR. Yaesu FT202R hand-held tx/rx, fitted S20-22, 6ch availability, for par- RF ammeter. 0-2A max. GBUN, QTHR. Tel 061-761 6616, evenings. ticulars see Radio Communication March '79 p204, four weeks old, as GEC personal tx/rx, type RC550TR; info, including circuit diagram, for brand-new, heavy-duty batteries, £75. Post paid. G3RDG, OTHR. Tel servicing purposes, would photocopy and return or buy. A. R. Bartle, 01-455 8831. 105 Mayfield Road, Thornton Heath, Surrey. Tel 01-684 0601 thome); or FT40113, recently overhauled, comp with matching spkr, mint 01-432 2020 (office). appearance, £300. GM3MBP, OTHR. Tel 089081 405. Unmodified R1155 rx, any cond, required to restore rx with df section AR88, orig spkr, mint, £14. Matching headphones, high quality, new, missing, why? G8CBE, QTHR. boxed, £7.50. AR88D manual, used, £. Pair selsyns, 4in dia 50V 5011, Hallicrafters SX110, with manual, in good cond, no mods please. with bin dia indicator, new, £16. Collins uhf coaxial relay, with connec- G4EFH, QTHR. tors, new, ES. All plus postage. Wanted: LM series frequency meter. LCR bridge; hf vtvm; hf d/b 'scope; fm sig gen, USM-16 or similar; ssb G3GUU, QTHR. tx, 160-10m; transistor gen coy rx, 1-30MHz. faulty rx considered, Racal Yaesu FRG7000, used only few hours, as new, unmodified, boxed, all why? Valves: JAN6021, 5702, 5703, 5(539. Tel 0908 313351 (Bucks), any accessories as supplied, going transceive, £310. 46 Shakespeare Road, time. Colchester. Tel 0206 67559. Pen recorder, 1mA centre or end zero type. G3RKH, QTHR. Tel 0636 Bantam, fitted S20. S24, case, nicads. charger, £0. Teletext decoder 812552. W W, in cabinet, psu, interface board, all wkg, £80. Futaba 4ch R /C Tunnel diodes, type IN2939, only a few needed for experiment, state tx/rx, nicads, charger, etc, 48 118in gliders, used 111 only, £150. price and number. P. B. Charlesworth, 5 Selworthy Road, Southport, G8ART, QTHR. Merseyside. Tel 71 69601. FRSDX400, 160-10m, 4m and 2m, new valves, re-aligned, vgc, £185. Oscilloscope, dual trace or beam, must be modern and in full wkg G4BMH, QTHR. Tel 0604 846533. order. G4DMN, QTHR. Tel 051-336 2386. FRG7, fine tuning, immac, spotless, unmodified, one year's SMC FT200, psu, or similar. Timms, 33 Isis Close, Long Hanborough, Oxon. guarantee, carton, manual, have purchased Drake, £150 plus carr. New Tel Freeland (0993) 881855. switched-selectivity pcb completed (SW Mversion for FRG7), two mech Solartron LM1010-2 dvm handbook or circuit diagram, purchase or filters, instructions, circuit, £25 post paid. BRSI2234, 16 East Parade, loan to photocopy, your price paid. Most grateful if anyone can help. Rhyl, Clwyd. G3OGS, QTHR. Tel Biggin Hill 73735, after 7pm, reverse charges. Q0Z03-10 valves, good price paid. Information (handbook) or similar on Ultra tx/rx 3A4-AG3 and 4A4-AHE4; would photocopy and return. W ANTED G3URV. QTHR. Tel 021-353 2146, after 8pm. Circuit/layout diagram W W2 MCRI rx, buy or hire. GM5PJ, OTHR. Purchase, hire or loan of maintenance handbook for Solartron CD1400 Redditch Radio Club wishes to borrow manual and/or circuit of RCA db 'scope; crt SE5/2A for same; maintenance manual for Milivac AR77, will copy and return, defray expenses, buy if necessary, for Instruments microvoltmeter MV29/3; will refund all postage or other young club member. G3EVT (sec), QTHR. Tel 078971 2041. expenses incurred in replying to above. N. Henry, G3OFK, 334 Nine Mile Eddystone EA12, KW77, Hallicrafters SX101, National NC300 or Ride, Wokingham, Berks. Tel Eversley 733674. HR060, must be in good cond and unmodified. G4FMO, QTHR. Tel XF9B, or aim spec 9 or 10.7MHz xtal filter for ZVC board; comp, or par- 0283 63767. tially built ZVC type board ISL600 series), why? Keeler, G4EZN, QTHR. K W2000, ac psu, in good cond. Write preferably. Mrs B. M. Moore, Tel Aylsham (Norfolk) (026 3731 3146. G3ORU, 30 Abbey Crescent, Sheffield S7 2QX. Tel 0742 383155. VHF rx R1132/A or similar. Can collect within reasonable distance. Marconi Atalanta rx. Cabinet for Ham marlund SP600 rx. Marine vhf G6DZ, QTHR. Tel 0279 57255. r/t, 12V. For disposal: HVV32A; load of test gear, valves and BC2217 freq meter; also class D wavameter. G4HYJ, "Chantreys", miscellaneous items; sae please. Cain, 18 Oaky Balks. Alnwick, North- Newton Reigny, Nr Penrith, Cumbria. umberland. Suitcase sets: Mk119, Mk122, Mk128/I29A, A Mk3, type 3 Mk2 (B2 RTTY rx adaptor, type FAE2, with matching en tuning indicator in 19in set), BP5/T5, AR11, A3. RXs MCR1, Mk301PP (psu for Mk301 rx). rack, and with manual. HAL ST-6000 demodulator/keyer, with crt Incomplete and/or damaged items considered. Taylor, G3UCT, QTHR. indicator. Good price paid for good wkg equipment. Bragg, 6 Tel Fleet (02514) 6998. Wherstead Road, Ipswich, Suffolk IP2 8JG. Keen newcomer to amateur radio would like to purchase National HRO Eddystone dial, type 888, in new or very good cond. G2FVVVV, QTHR. Senior, AR88, Super PRO, 828, or similar rx. Tel Peter, Fareham Tel Keresley 3363. after 6pm please. 281745. Trio R599D or S model rx, also S599 spkr console, only interested in Valves, type ESA1500, AG238, BR1126, RG3/1250, GXU4. G3SMK, immac units. G3FCVV, OTHR. Tel Leeds (0532) 585044, evenings or OTHR. Tel Earlsvvood (\Narks) 3423, after 7pm. weekends. W G16 3-port switch, VVG16 3-port circulator, all letters answered. Eddystone 888 or 888A, unmodified, mint or vgc, with or without F6DPH, Millet Ph, 4 Bis Place des Tilleuls, Fontaine le Port 77770, Char- accessories, collection arranged reasonable distance or mutually agreed trettes, France. motorway oasis. Furness, GM3RUI. 33 Leslie Crescent, Westhill, Skene, Bandspread 8Orn coil for HRO. 0-9-2.050 gc coil. G4CIB, QTHR. Tel Aberdeenshire. 0452 830540. To keep station operational: valves 00206-40, QQ203-20, YL1000, Trio JR599 custom special rx, in good cond. For sale: Lee Electronics YL1130; Cossor Commando spares; buy or borrow Cossor Commando 2m 5dB cotinear, immac cond, £33 ono. G4EXT, OTHR. Tel 1)1-856 4595. CC302 handbook; Babani's International Radio Tube Encyclopaedia, third edition, 1958. Rycroft, G8IGZ, 4 Lanherne Avenue, St Mawgan, Newquay, Cornwall. Tel St Mawgan 226. 0TH: Hampshire. Dorset, rural area, three beds, detached, with Ver- satower, price E20/26,000 cash; would consider other suitable property provided planning permission for tower could be obtained. Tel 0406 Looking ahead 362501. 18AVT/WB 80-10 vertical. S. Macdonald, GM4GUL, 5 Lower Glebe, Aberdour, Fife. Tel Aberdour 860435, evenings. 11-12 May— RS GB « Amateur Radio Exhibition, Alexandra Palace, Lon- Muirhead D901 facsimile tx, suffix D preferred but others considered. don. price and details. McGuffie, 4 Royal Crescent, Stranraer, Wigtownshire DG9 8HB. Tel 0776 2716. 28-30 June—The Electronics Bazaar, Alexandra Palace, London N22. 813s, pair needed, new and unused, details. GVV2SB, 27 Highfield 21 July —13ARTG Convention, Public Hall, Harpenden, Herts. Avenue, Mynydd Ise, Mold, Clwyd. Tel 024 454 5177. 15 September —RSGB HF Convention, Birmingham. Manual or circuit for National HRO-MX, purchase or loan. G3YLL, 22 September—Scottish VHF Convention, Dundee Technical College, QTHR. Dundee. Pye Bantam HP1A M, E band, multi channel, not modified, in good 30 September—Sixth Welsh Amateur Radio Convention, Blackwood, cond, plus battery trays and nicads, good price paid. T. Randall. 4 Minf• Gwent. fordd Road, Caergeiliog, Holyhead, Gwynedd LL65 3NA. 13 October—El/GI Convention, Ballymascanlon Hotel, Dundalk, Eire.

RADIO CO M MUNICATION May 1979 IF YOU WANT PERFOR MANCE- IT'S GOT TO BE LUNAR

Lunar Electronics, based in San Diego, California, are undoubtedly the leading manufacturers of 144MHz and 432MHz Linear Amplifiers and Preamplifiers. But don't take our word for it, ask a LUNAR user. TAKE A LOOK AT THE RANGE.

LINEAR AMPLIFIERS 144MHz 2M10 BOP BO Watt all mode, Linear /Preamp E120+ VAT 123% 2M30 160P 160 Watt all mode. Linear/Preamp £160. VAT 123% 2M10 250P 250 Watt all mode £30 • VAT 123% HF HF3•100L2 Linear/Preamp 1.13-30MHz, 200 watt PEP output IMO watt continuous) E120+ VAT 123% PRE A M PLIFIE R S 28MHz PA28 213N1Hz 1.1 db N.F. E20+ VAT 123% 144MHz PA144 Preamp 1.5 db N.F. E20 + VAT 123% PAI144 RF Switching Preamp 1.9 db N.F. E28+ VAT 121% 432MHz PA432.2. 1-6 db N.F. E22 + VAT 124% PAE 432-5. EME USE. 1.0 db N.F. 16 db Gain £40 • VAT 123% Available either direct from us, the EXCLUSIVE AUTHORISED UK Et EURO. PEAN DISTRIBUTORS, or from or...WIT-our appointed agents: C. B. Elec- tronics. SMC Ltd, Waters Er Stanton, Efredhurst Electronics. Crayford Elec. ironies, Amcomm Services, GM3ZBE (Aberdeen) and GMBGEC (Edinburghl: 7MP Electronics; See Rad Comm Adverts.

SPRING TIME IS ANTENNA TIME As appointed Northern agents for VHF Communications. we are pleased to offer their high quality Antenna Rotator Units

KR400. (95.62 inc VAT. KR600. (Heavy Dutyl £149.82 Inc VAT. KR 500. Vertical Elevation Rotor £135 Inc VAT.

EDL144S. £144.00 inc VAT. EDT144/28. £112.50 inc VAT. EDL432P. £135.00 inc VAT. E01.432. £56.25 ine VAT. ISee previous ads foe further details)

PLUS UKW 1296MHz TRANSVERTER available from stock £80.00 inc VAT

U.K. Distributors for DAVIS ELECTRONICS FREQUENCY COUNTERS egt 41 1 111 .11111111111 . I

M NI NEW! soomHz Mini Counter 7208 COUNTER 04fl £145 + VAT 8% General purpose low cost counter without the sacrifice of basic performance p "Check the features we have that some other low cost counters don't have."

• AI Teed C•81101 • SernitiVill 10 MV ir 150 Mali • Correlate Auto Deena Pere • 8 Digit 4" LED Dusky ¡ Malt-TICINO • 24011 or I2V Operetion • Seised* Gaup Tones II Seca • 1 sect • Push Benxi Courds • Mtn Negev \ MVP J41:IC • • 12V input Gets Lip • Creed TRW Base (1 own/. q .111

S.A.E. for full set of Data Sheets, or see our stand at most of the coming Rallies Et Exhibitions. Trade Et Export enquiries welcome. SOTA COM MUNICATION SYSTEMS LTD.

26 CHILD WALL LANE, BOWRING PARK, LIVERPOOL, L14 6TX ENGLAND. Tel: 051-480 5770

Telex: 628702 SOTA G Hours: 9.00arn to 6.00pni, Monday to Saturday

RADIO COMMUNICATION May 1979 465 188 BROADHURST GARDENS LONDON NW6 3AY RadioShack Telephone: 01-624 7174

PRICE LIST, MARCH 1979 (prices include VAT)

R. L. DRAKE PRODUCTS 7073 Hand mie, for TR-7/UV.3E £13.50 276 Crystal Calibrator for Century 21 £19.80 7077 Desk mie, for TR.7/UV-3E £24.75 KR-1A Dual paddle assembly .. £27.00 COM MUNICATIONS RECEIVERS DU = Dummy Load, 300 watts £15.75 KR-5A Single-paddle keyer. 6-14vdc .. £31.50 Et ACCESSORIES DL-1000 Dummy Load, 1000 watts • .. £29.70 KR-93 Ultramatic keyer dual paddle R-AC Receiver- SSB, AM, SW, RTTY £495.00 RCS-4 Remote Control Antenna switch £83.25 117vac.'6.14dc . .. £56.50 FL-250 Fiber for FI-4C (250Hz) .. £39.60 13.1000 Balun 4:1 for MN-7/MN-2700/ FL-500 Filter for R-4C (500Hz) .. £39.60 MN-4C only £18.00 BARLO W-WADLEY FL-1500 Filter for R-4C 500Hz) £9.60 1525-EM Encoder mie, £36.00 FL-4030 Filter for 11.4C (4000Hz) £39.60 XCR-30 General coverage receiver .. E149.85 The R. L. Drake Company are no FL-6000 Filter for R-AC 16000Hz) £39.60 XCR-30 General coverage receiver with longer making the following items: £170.00 4-NB Noise Blanker for R-4C £64.03 FM unit .. MS.4 Matching Speaker R-4C, SPR-4, however, we still have a few of TR-4CW £24.75 each -please check our stock STANDARD position before ordering: Crystals - Accessory Crystals for R-4C £4.95 £45.00 C-146A 2m FM Tcyr. 2w 5 channels SPR-4 Receiver -General Purpose .. £460.00 AA-10 1w in-10w out 2m Amplifier .. (hand held) with leather case/tone DC-PC DC Power Cord for SPR-4 .. £4.05 WV-4 RF wattmeter 20-2COMHz £64.80 burst/S20/22 £140.62 Crystals - Accessory Crystals for SPR-4 £4.95 AT-19 Flexible antenna .. £5.56 DSR-2 VLF/HF Digital Synthesized HY-GAIN ANTENNAS HP-7 Set of 10 rechargeable ni-cads .. £9.66 Receiver . . 1:2250.00 18H7 6-80m Vertical Tower .. £253.12 Battery charger ' ' • ' ' £5.06 SSR-1 Receiver-General Purpose .. £175.00 12AVO 10-20m Trapped Vertical .. [42.18 Hand microphone £15.18 14AVQ/WB 10-40m Trapped Vertical. £89.06 Basemaster £24.76 TRANSCEIVERS & ACCESSORIES 18AVT/WB 1093m Trapped Vertical .. £85.50 Extra crystals S21/23/24 R3/4/5/6/7 £3.89 78.7/DR-7 Transceiver with gen. coy. 18V 10-80m Vertical , £31.28 Digital . £864.00 THEDXX 6 element beam for 10/15/20 £230.62 PS-7 120/240V Power Supply for TA-7 £135.00 TH3MK3 3 element beam for 10/15/20 £176.62 RV-7 Remote V FO for TR-7 .. .. £139.50 TELEX CO M MUNICATIONS INC. TH3JR 3 element beam for 10/15/20 £127.68 MS-7 Matching Speaker for TA -7 .. £24.75 TH2MX3 2 dement beam for 10/15/20 £123.46 LIGHTWEIGHT HEADPHONES 3.2-20ohms NI3.7 Noise Blanker for TR-7 £64.80 HY.OUAD 2 element quad for 10/15/20 £190.12 HFC-91 Underchin 1.5oz with foam ear- FA-7 Fan for TA-7 Et PS-7 £18.00 DB 10-15A band 15 beam £129.38 pads £6.08 AUX-7 Range programme board Er 1 204BA 4 element 2Orn beam £174.38 HMC-2 Underchin I.5oz with plastic ear- Receive module ...... £31.50 203BA 3 element 20m beam £132.19 tips . £9.00 RAM-7 Range receive modules (500kHz 153BA 3 element 15m beam £70.58 HTC-2 1.6oz Twin Receiver headphone £14.40 for AUX-7 £5.40 103(3A 3 element 10m beam £57.38 DUAL MUFF HEADPHONES ATM-7 Range transceive modules 40213A 2 element 40m beam £177.75 C-610 3 -2-20ohms Dual Receiver 15C01tHz) for AUX -7 C5.40 511 Heavy duty spring .. POA Magnetic .. . 6.75 SL.300 CW Filter (300Hz) for TR-7 .. £39.60 499 Flush body mount .. £11.69 SWL-610 2000ohms Dual Receiver SL-500 CW Fitter (500Hz) for TR-7 . £39.60 417 De luxe spring .. £8.83 Magnetic . £7.99 SL-1800 SSB/RTTY Filter (1BD0Hz) for 492 Miniature spring .. £4.60 C-12103-2-20ohms Dyne mic foam pad- TA-7 £39.60 £18.45 LA-1 Lightning arrestor.. £22.84 ded . SL-6003 AM Filter 16000Hz) for TR-7 .. £39.60 LA-2 In-Line Lightning arrestor £3.71 C-1320 3 -2-20ohms TELEX'S finest £25.65 MMK-7 Mobile mounting kit lease, 8N-86 Ferrite balun £15.19 filters, cable) TR-7 C33.75 BOO M MICROPHONE HEADSETS MN-7 ATU/RF wattmeter 160-10m. 'headphones as above) 250W £123.75 YAESU CM-610 As C-610 with high 2 Ceramic MN-2700 ATU/RF wattmeter 160-10M. FT-202R 2m 1w Hand held Tow fitted microphone £29.70 2kw £199.80 3 ch £119.81 CM-1210 As C-1210 with 'high ¡ Ceram- WH-7 HF wattmeter/V6WR bridge .. £59.40 ic microphone £38.25 385.0034 Service Manual for TR-7 .. £16.50 TEN-TEC CM-1320 As C-1320 with high 2 ' Ceram- TR-4C W I RIT) Transceiver AM/SSB/ ic microphone £47.25 CW with R.1.7. £504.00 509 Argonaut 5w SSB/CW Tow 3-5-30 £247.50 CM-1320S As CM-1320 with single head- AC-4 120/240V Power supply for 540 Triton 1V 200w SSB/CW Tcvr £498.00 phone TA-4 CW/T-4XC. £108.00 544 Digital Triton 1V 200w SSBICW Tog fall the above headsets fitted pti switch, 34-PNB Plug in Noise Blanker for T8.4Ciii. £72.00 3-5-30 DC-4 DC Power supply for TR-4CW, 54,5 Omni-A Analogue Transceiver .. £662.50 MICROPHONES (hand held battery powered) T-4XC Et R-4C £139.50 546 Omni.D Digital Transceiver _ £785.00 ProCom 1 Electret High Output £11.70 RV-4C Remote VFO for TR-4CW .. £108.00 570 Century 21. 70w CW Tcvr 3.5-29MHz £V0.50 ProCom 11 Electret Variable Gain .. £17.66 FF-1 Crystal Control for TR-4C W .. £38.25 574 Digital Century D £281.25 CB-73R Dynamic Noise-cancelling Ire. UV-3E 144/432 MHz FM Transceiver £495.00 405 Linear Amp. 100w. 3•5•30MHz .. £112.50 lay switch) £23.40 P5-3 AC Power supply for UV-3E113.6V 210.,E CIA) 115/230vac/13vdc peu for CB-73S As above with 6-wire universal 9A1 £69.75 Argonaut _ . £27.00 lead £24.75 UMK-3 Remote Trunk kit for UV-3E .. £54.00 251/E (9A) 115/211111vacil3vdc psu for Argonaut/405 HAL COM MUNICATIONS CORP. LINEAR AMPLIFIER 262G/ E (18A1115/230vacil3vdc psu for L-7 Linear Amplifier 160-10m C766.00 Tritons £100.00 ELECTRONIC TTY SYSTEM 247 Tuner .. £49.50 DS-3000 KSR version 3.X 'ASCII/ TRANSMITTER 277 Tuner/ SWR £58.50 Baudot/Morse) . £1134.00 T-4XC Transmitter AM/SSB/C W £495.00 212 Crystal 29-0-29.5MHz for Tritons .. £4.50 DS-3000 KSR version .2.X 1.11SC1ii 213 Crystal 29• 5-30-0MHz for Tritons .. £4.50 Baudot £186.36 ADDITIONAL ACCESSORIES 240 Converter 160m for Tritons £72.00 ST-6000 Demodulator/ Keyer with 'scope £432.00 £194.40 TV-42 LP Low Pass Filter 100w £10.13 241 Crystal Oscillator for Tritons f22.50 ST-5000 Demodulator/ Keyer TV-3300 LP Low Pass Filter 2kw £18.00 242 Remote VFO for Tritons .. £119.25 RVID-1005 Visual Display Unit (Baudon E296.12 RP-500 Receiver Protector .. £72.00 245 CW filter for Tritons £19.80 DKB-2010 Dual mode keyboard with 7072 Hand mie. for TR-4CW/T-4XC £13.50 249 Noise Blanker for Tritons .. £19.80 128 key buffer memory £345.60

466 RADIO COM MUNICATION May 1979 TRIO EQUIP MENT AMECO SVMK /2M Mounting kit . £5.62 UGP/2M Unipole Et ground plane £8.12 IS 820$ 160-10m Tcvr. 200w PEP with EQUIPMENT NM/2M Mobile halo with mast.. E4.45 OCMK Code practice oscillator kit £12.38 DG-11 £899.00 PN1H2/2M 2-way phasing harness for OCM W Code practice oscillator wired £16.20 two 2m ants. . £7.82 IS 520S 1-8-28MHz SSB Tcvr. 2COw PEP £575.00 PLF-2FET Receiver preamp £47.25 PMH4/2M 4-way phasing harness .. (18.62 £67.50 SM 220 Monhorscope . £251.00 PT-2 FET Transceiver preamp. 10-160m O8/70cm Double 8 slot-fed yagi .. £17.71 IS 700S 2m all mode dig. Ten. .. £637.00 MORSE CODE COURSES PBM 18/70cm 18 element Parabeam .. £21.38 101-33 Senior Code Course. IR 70102m CW/SS8 Ten% 10w output £189.00 MBM 48/70cm 48 element Multibeam f24.92 33rpm Record .. . (5.40 MOM 88/70cm 88 element Multibeam £3.15 £6.48 IR 7200G 2m FM mobile Tcvr. 10w fit- 101-T Senior Code Course. Cassette TAS 2m 5/8 mobile whip . £13.59 103-33 Advanced Code Course. ted lOch , £189.00 U5 70cm Colinear 5.6dB £20.25 £2.80 33rpm Record .. DL Double lashing chimney kit . £5.92 IR 7400A 2m FM mobile Tcvr. 800ch £365.00 £3.78 103-T Advanced Code Course. Cassette W6 F wall bracket . . £2.83 IR 7920 2m FM mobile Tcvr. lOw. PLL 106-33 Gen, class supplementary course W21 21" wall stand-off bracket .. £11.09 33rpm Record .. £2.80 80FM ch . £235.00 W24 HD 24" wall stand-off bracket PUBLICATIONS heavy duty ...... £15.77 TA 2300 2m FM penable Ten. PLL 80 3-01 Radio Electronics Made Simple £2.00 SPM 16' x 1" Portable Mast .. £11.31 £310.00 102-01 Amateur Radio Theory Course £3.50 FNI ch PME 4' extension for double arrays [1.91 £2.50 TA 8300 70cm FM mobile 10w Tee. fit- 23-01 Novice Class Theory Course . A4 4' 6' x Ir mast (2.89 ted 4ch £267.00 A5 5' x 1" mast £2.16 ASTATIC MICROPHONES Ag g' x i }" mast £5.82 TA-320070cm Tcvr. fitted 3ch. .. £198.00 A10 10' x 2" mast .. .. £10.06 T-UG9-0104 Golden Eagle gold-plated R-300 General coverage Receiver £185.00 CP1 Cross-over plate 2' s r .. .. £.50 transistorised £69.76 The above are some of the main Trio JBL 59/66' jointing sleeve for 2" masts T-UPG-13104 Silver Eagle chrome-plated only ...... f2.12 transistorised . . units- we also stock the accessories, £49.50 JBL 59/15 15" jointing sleeve for 2" UGB-D104 The famous Crystal 0104 .. oscilloscopes, etc. £31.50 masts only . . .. £5.00 T-UG9-D104 Transistorised amplified JBL 29 Universal clamp 11" bbom to 13104 grip-f-t £40.50 l'-2" mast ...... £1.20 T.UP9-0104 Transistorised amplified CDE ROTATORS J8L 30 Universal clamp 1- boom to AR-20 £38.81 p.t.t. !grey Or black) £45.00 r-2" mast .. .. £1.20 525 DL6 Dynamic Hand Microphone. AR-22L £48.38 JBL 53 Universal clamp 1" beam to AR-30 £46.13 4002 £12.15 £1.20 AR-40 £53.41 400 Dynamic Hand Microphone. 'Buckeye' £.85 JBL 58 3-hook guy wire clamp non- 565 MS Hand Microphone FET amplified. CD-44 £106.88 rotating ...... £131 'Mariner' . . £1.50 HAM-3 £156.38 JBL 63 Universal clamp 1-1h" boom 10 BIG-TALK £89.44 0104-M Hand Microphone 0104 FET 1-2" mast ...... £0.98 amp 4-wire .. TAIL-T WISTER . £241.88 04.30 JBL 64 Die-cast clamp 11* boom to 1" 0104-M6 Hand Microphone 13104 FET mast ...... £0.93 amp. 6-wire COAXIAL CABLE £28.36 JBL 65 Die-cast clamp 1" boom to 555 4-wire Hand Mic. noise-cancelling UR-67 52ohms per metre £0.60 l' -2' mast £0.98 'Trucker' .. £21.60 JBL 73 Heavy-duty universal clamp .. E1.64 UR•7652ohms per metre £0.20 557 6-wire Hand Mic. noise-cancelling MBP Mast base plate for 2' diam. mast £2.72 11234 52ohms per metre £0.55 *Trucker' . £26.10 UR-70 75ohms per metre £0.20 531 Hand Mic. mobile. High Z £7.65 RG-174U per metre £0.30 539 Hand Mic. mobile, noise-cancelling £7.65 PHILIPS 300ohm ribbon per metre £0.10 1104C Desk Mc. FET amplified £6.00 14swg enamelled copper wire per metre £0.12 AAC-4000 Language-trainer. comprising 4-core rotor control cable per metre £0.20 Casette Recorder and headphone with 5-core rotor control cable per metre £0.25 SHURE MICROPHONES microphone attached £129.60 8-core rotor control cable per metre £0.35 201 Hand held ceramic .. £14.18 AAC Language courses for use with the 202 Hand held noise-cancelling ceramic £14.85 AAC-4000 trainer above THE FABULOUS BEARCATS ARE 401A Hand held magnetic £16.20 Courses are available in FRENCH/ IN STOCK AGAIN! 404C Hand held £24.98 GERMAN RUSSIAN/SPANISH/ 444 Desk model £31.72 ITALIAN/PORTUGUESE and WE CAN NOW OFFER 2 MODELS 5261 Desk model with preamp £:03.48 ENGLISH. There are four parts to a Bearcat 210 £199.80 full course. Bearcat 250 . £249.75 JAYBEA M ANTENNAS Pans 1, 2, 3 leach part .. £36.72 4Y/4M 4 element folded dipole yagi £14.86 Part 4 • .. £41.04 BARKER Et WILLIA MSON (Send LARGE sae -for brochure please) C5/2M 58 glass fibre colinear. £36.42 331A Little Dipper 2-230MHz grid-dip 5Y/2M 5 element folded dipole yagi £8.67 Teter £1.00 8Y/2M 8 element folded dipole yagi £11.25 334A Dummy load/Wattmeter. lkW £135.00 10Y/261 10 element folded dipole yagi £4.58 FASTFIT CONNECTORS 371-1 Widerange Anenuator £33.75 PBM 10/2M 10 element Parabeam 129.72 CPF1259-10 PL-259 type for UR-43/ £16.88 375 Pretax antenna switch P8M 14/2M 14 element Parabeam £6.12 UR-76 £0.65 £15.30 377 Coax relay 8XY /2M Crossed Salement yagi £22.50 CPF1249-15 Female line-connectors 551A Antenna switch 6-way £15.30 10XY/2M Crossed 10 element yagi £028 for UR-43/76 £1.00 595 Antenna switch 6-way .. £16.20 PMH/2C 2-way phasing harness 15.95 CPF1259-7 PL-259 quick-dis. Male for 134/2M 4 element quad yagi £18.98 UR-43/76 .. £1.08 THE AMAZING AR-240 £195.00 0612M 6 element quad yagi £24.75 CPF15858 Cable splice, twist-on for Synthesized, 800 channel, hand held TCVR. Com- 13512M Double 5 slot-fed yagi £15.77 UR-43/76 .. . £0.97 plete with ni•cads and charger unit. D8/2M Double 8 slot-fed vas, £21.02 CPF1259-13 PL-259 for RG.8/UR-67 €0.87

WE ARE SITUATED just around the corner from WEST HAMPSTEAD UNDERGROUND STATION which is on the BAKERLOO LINE. A few minutes walk away is WEST HAMPSTEAD MIDLAND REGION STATION and WEST END LANE on the BROAD STREET LINE. We are on the following BUS ROUTES: 28, 59, 159, C11

WE ARE OPEN 9-5 MONDAY to FRIDAY, 9 12.30 SATURDAYS. We are closed for lunch between 1 p.m. and 2 p.m.

TELEPHONE 01-624 7174 with your ACCESS or BARCLAYCARD number for immediate DESPATCH

CREDIT FACILITIES AVAILABLE ON ORDERS OVER £100

for details send 15p stamps or 4 international reply coupons

TRIO DRAKE SALES SERVICE

RADIO COM MUNICATION May 1979 467 LEE ELECTRONICS LTD

01-723 5521 ESTABLISHED FOR MORE THAN TWO DECADES SPECIAL OFFER! 400 EDG WARE ROAD. LONDON. W2 Telex: 298765 OPEN MONDAY TO SATURDAY Fr2o2 LONDON'S LARGEST STOCKISTS OF YAESU • ANTENNA SPECIALISTS • STANDARD • ICO M • LUNAR • JAYBEA M • SST • QM70 • ATLAS • ETC m H A N D P O R T A B L E 2 ACCESS • BARCLAYCARD • INSTANT HP • P/EX

ONLY £88.00 FRG-7 - DIGIT AL DISPLAY Yes. The world famous FRG•7 is now available with digital read out fined by Lee plus VAT Electronics in place of kHz dial. . Special price £27.00 • 124% VAT Full range of accessories available li or customers who already own FRG-7's we can supply the digital read-out complete with installation instructions f 39 50 . 12;% VAT

MICR O W AVE MODULES DESPATCHED TO ANY PART OF THE WORLD POST FREE TRANSVERTORS FREQUENCY COUNTERS CONVERTORS ATV435: 51 convertor £26.58 £30.00 M MT 144 '28 Transvenor £79.00 M MDOSO.'500Mhz Counter £63.8g M MC 432/28S for Oscar L26.58 Mrom1 112596% 44ro '.2, C ,e £20.00 M MT 432:28S Transvenor with M500P 10 Prescaler £25.00 MMC 432/144S for Oscar £26.58 M MC28, 144 up convertor E18.00 Oscar shift £119.00 MMC 70 4rn convertor £18.00 LINEAR AMPS All 2m converters can be supplied M MT 432 • 144R Transvertor £151.00 M MC 70 LO 4m convertor f20.00 with IF outputs ol 2 4 -12-14 VARACTORS MM L432 100W 020 .00 MMC 144 2m convertor £18.00 18 28MHz 70cm models wrih IF out-

MMV 129623cm Triplet £30.00 MML144 80W £120.00 MMC 144 LO 2m convenor £20 :00 puts of 28 14 18 or 144MHz ALL MICRO WAVE MODELS SUBJECT TO VAT IN UK 8% ON FREQUENCY COUNTERS. ALL OTHER MODELS 12./.

A.S.P. M OBILE AND BASE STATION ANTENN AS ICO M RANGE Asp201 1W 2m mobile E3.50 Asp393 ¡NA/ 3dB 2rn mobile £17 Asp E462 70cm 3dB mobile £7.23 C701 transceiver and Asp20Cr3 I 3dB 2m mobile £7.50 Asp no hole boot mount £3.70 Asp E667 70cm 5d13 mobile £16.90 power supply £388.00 Asp629 }VV 3dB 2m mobile £7.60 Asp magnetic mount £8.95 Asp A659 UK 70cm 5dB. C2I5 2M portable £141.33 Asp677 I 308 2m mobile £13.50 Asp cutter with cable £6.75 base antenna £22.00 C202S 2M SSB £176.89 Post Fi Package; £1.00 +VAT 8% C402 70cm SSB £56 00 C240 2M Transceiver (16800 C245 2M FM/SSB £354.62 YAESU MUSEN (FULL RANGE AVAILABLE) FREE DELIVERY IN UK C211E 2MF M/55F3 £496.00 Xtals for 215/22 p/pair £4.50 Cases 202/215/402 (6.75 FT901D M £853.00 FTIOIE £515.00 CPU250ORK £308.00 FRG7000 £327.00 Mobile mounting FT901D ' DE £737.50 FRIOID f525.00 FT225R €4.87.50 Y0100 E145.00 bracket 202/215 £10.75 FT301 £515.00 FRIO1DD £615.00 FT225RD E535.00 QTR24 £16.00 FT301D £588.00 FL101 £453.00 FT227R £213.00 YH55 £8.75 SHURE MICROPHONES FP301 £98.00 F17 £318.00 FT227RX M l.00 YC500J (168.50 444 Desk adjustable £22.00 FP301D £162.50 FL110 £130.00 FT202 (106.50 YPI50 £58.50 562 Desk noise uncoiling C28.80 FV301 £86.00 FP4 £35.00 FRG7 £187.00 YDB44 £19.50 525T Desk power mic £34.20 FC301 f 108 00 FL21030 £311.00 FRG7DIG C227.00 Y0846 £7.50 401 Hand mic high z All prices subject to 12 % VAT 202 Hand mic nicancelieg £13.20 201 Hand microphone £12.60 OTHER MODELS AVAILABLE

STANDARD C432 70cm TRANSCEIVER SST ANTENNA TUNERS

SST2SST1 CoaxRandom Wire Wire Tuner Tuner £28.75£22 AO THIS 6 CHANNEL 2.2 WATT TRANSCEIVER COMES COM- PLETE WITH LEATHER CARRY CASE AND FITTED WITH SST3 Impedance Match unit £1350 433.2 AND 433 • 5 MHz. £169.95 + VAT ROTATORS AR22 (43.00 CD44 £95.00 THIS SOPHISTICATED UNIT HAS EXCELLENT SENSITIV- AR40 £47.50 ITY, OUT PERFORMING MOST OTHER RIGS, JUST THE HAM 11 f129.00 K R400 £85.00 UNIT NOW 70cm REPEATERS ARE OPENING UP ALL OVER KYOCUTO DIGITAL 2015 THE COUNTRY. A FULL RANGE OF ACCESSORIES ARE 10VV mobile 400ch Tx/ru £246 AVAILABLE FOR THIS MODEL. J-BEA M ANTENNAS ALL MODELS IN STOCK ACCESSORIES Al above prices + VAT, carr. free Extra channels £4.50 + 8% VAT HELICAL ANTENNAS CMPO8 External Microphone £15.00 + 14% VAT 2m with BNC f3.85 each 2m with PL259 £3.85 each SMP30 External Spk/Mic £16.50 + 14% VAT 2m for IC215. C12 Wall Charger £5.75 + 14% VAT Trio 2200 Ge. standard C146A £3.50 - BCA Base Charger £22.50 + 14% VAT AI + post 25p + 14-% VAT N-10 Set Ni-cad £13.50 + 14% VAT SEN D 25P IN STA MPS FOR .4 Helical Antenna £3.50 + 14% VAT CO MPLETE PRICE LIST AND CATALO G UE

SWR25 This ever popular twin SWR and power meter covers UH74 SWR and power meter switch- • 3-5-150MHz at £10.50 plus 8% able HF. 2M 8 432MHz wart VAT and 25p P Et P. - .. remote head at £1425 plus 8.. SWR 15 Single mete r SWR and VAT and 25p P Er P. I FS 3.5 -150N1Hz at E8.50 plus 8% VAT and 25p P Et P.

RADIO COMMUNICATION May 1979 sign of fine communications Authorised Distributor for TRIO equipment in Yorkshire and the North East. TR7600 2m synthesized mobile/fixed 265.00 3.50 THIS MONTH'S LAR SPECIAL- Microwave Modules Transverters; Spare power lead 1.25 .15 M MT 432/28S, f105; M MT 144/28. £175. both inc VAT Et post free. LAR Power supply unit and Ni-Cad charger for TR2200G: PS1200 GX TR3200 and 182300 24.50 .86 VB2200GX 10W P.A. for 2200G / GX 45.00 .86 SUPER PRICE REDUCTIONS 185300 70cm FM mobile 10W transceiver fitted 4 channels 245.00 3.50 Price 183200 70cm FM handy transceiver fitted 3 channels 186.00 3.50 TRIO EQUIP MENT inc VAT Ca " £ MB1A Matching mobile mount 9.00 .67 E Spare power lead 1.25 .15 8820 The ultimate matching receiver to the 19320 773.00 3.50 8300 General coverage receiver 185.00 3.50 YG455C CW filter 500Hz 60.00 .36 HS5 Communications headphones, tailored response 23.173 .67 YG455CN CW filter 250Hz 67.50 .36 HS4 Communications headphones tailored response 10.50 .67 YG88A AM filter 38.00 .36 MC50 De luxe desk microphone dual impedance TS820S 160-10m transceiver 200W P.E.P. (with DGII 814.00 3.50 PTT locking bar 27.00 1.06 TS820 160-10m transceiver 200W P.E P 695.00 3.50 MC35S 50K fist microphone 13.00 .44 001 Digital readout to 100Hz 120.00 .86 MC3OS soon fist microphone 13.00 .44 VFOB20 External VFO 121.00 3.50 LF30A HF low pass filter 1Kw 90dB. Stop band rejection 18.50 .67 DS1A 12V dc inverter.Supp/f itted toc all orders TS820S/TS520S 42.00 .86 BPF2A 2m band pass filter 144-148MHz 50W rms YG88C CW filter 8 pole 37.00 .36 100W P.E.P 28.00 .86 SP820 Speaker 38.00 1.16 Mizuho SE1-2M 2 metre SSB/C W portable transceiver 165.00 3.50 SP520 Matching speaker 8ohm 17.50 1.06 VHF AM ATEUR RECEIVERS SM220 Monitor scope 231.00 3.50 $89 Tuneable/crystal 2m FM receiver 144 146MHz 45.00 .86 858 TSB20 scan board for SM220 48.50 .44 AMR217B Scanner with 8 crystals. The best and most popular AT200 1.8 to 30MHz antenna tuner 93.00 1.06 Mains/battery 118.12 1.06 TL922 HF Linear amplifier 160-10m/2Kw P.E.P. Crystals for above. Each 2.40 .15 2 x 3.500Z tubes 780.00 3.50 HF MOBILE ANTEN NAS 1S5205 1.11-28MH: SSB transceiver 200W P.E.P 530.00 3.50 *G* whip tribander helical 20/15/10 21.15 1.06 VF05205 Remote VFO 101.00 3.50 'G' whip multimobile 20/15/10 24.30 1.06 SP520 Matching speaker 19.00 1.06 L.F. coils for the above whips 005 Digital display/40MHz frequency counter 117.00 1.06 (Specify whether tribander or multimobilel 6.07 .66 DK520 Conversion kit allows use of 005 with TS520 10.50 .67 Telescopic whips for the above 3.00 .66 YG3395C CW filter 39.00 .36 Base mount for ell 'G' whips 3.82 .66 SM220 Monitor scope 251.00 3.50 Extendarod 40' booster 10.12 1.06 855 TS520 scanboard for SM220 46.50 .44 TS120V 80-10m mobile transceiver 20W P.E.P. 399.00 3.50 VHF/UHF 'X BEA MS All 'J'-Beam products available PS 20 AC power supply for TS120V 51.00 3.50 ROTATORS MB100 Mobile mounting bracket 16.50 .67 AR40 15 core cable required I 53.44 3.50 YKI38C CW filter 28.50 .36 FU200 For lightweight 2m beams 39.50 3.50 SP120 Matching speaker 25.00 1.06 087500 lArill take 3 element tribander 105.76 3.50 VF0120 Remote VFO 91.00 3.50 087600 Will take 2 element 40 metre beam 150.75 3.50 AT120 Antenna tuner 1100W) 67.50 1.06 DR7600P As above but with preset or manual controller 200.25 3.50 TS7005 2m all mode digital readout transceiver VHF MOBILE WHIPS simply the best 537.00 3.50 ASP201 I wave 2m 320 1.55 VF07005 External VFO 90.00 3.50 ASP157 } 'wave gutter mounted 2m 1028 1.55 SP70 Matching speaker 20.00 .86 ASP2039 I wave 2m 9.72 1.55 187010 2m SSB/C W mobile transceiver 10W output 189.00 3.50 ASP677 ) wave 2m 1620 1.55 15170 2m/70cm all mode dual bander t.b.e. ASP2011 a wave disguise 2722 1.55 TR7400A 2m FM 30W mobile transceiver 803 channels 336.00 3.50 ASP482 a wave 70crns 821 1.55 187500 2m FM mobile 10W transceiver PLL with all ASP667 Colinear 70crrts base station 20.00 1.55 80 FM channels 235.00 3.50 AS P655 I wave 2m base station 21.60 1.55 PS6 Matching PSU for 187500 58.00 3.50 AS PA659 70cms 21.60 1.55 TR2300 2m FM portable transceiver PLI with all M161 No hole boot mount . 320 1.55 80 FM channels 195.00 3.50 K220 Magnetic mount 7.56 1.55 V132300 lOW booster. Available February 1979 58.00 86 K220A Magnetic mount 7.56 1.55 MB2 Mobile mount. Available February 1979 18.50 .86 All ASP mobile antennas and accessories available RA1 Helical rubber antenna 6.75 .36 P1310 Pack or 10 ni-cad batteries lEver Ready, 12.40 .28 NB. Goods subject to p ice's ruling at date of despatch

Authorised Distributor for TRIO, CITY No. HOW TO BUY! Equipment & Area Distributors for OFF THE PAGE - Simply choose the LIBRARY 27 JAY BEAM, ANTENNA product and then complete the SPECIALISTS & HILOMAST coupon and enclose cheque. THE HEADRO W PRODUCTS. e Open Mon-Fri 9.15 6.30pm Saturday 9.15-5.30pm FROM THE SHOP- We're close to LEEDS AMATEUR RADIO * H.P. Terms on request the station and car parks. Do call in 27 Cookridge Street, Leeds 2 _prretv_ and discuss your requirements. Telephone: Leeds 452657 Post to Leetts 7m 7etir Radio, 27 Cookrtrige Street, Leeds 2- - enclose cheque for e Plus 50p for Brochure TO BARCLAYCARD/ACCESS I " to purchase._ I authorise you to debit my Barclaycard/Access Account Irel Name with the amount of £ My IVo. is sbso- eo"pi. Address 111 R oe RC2 Signature _

RADIO COMMUNICATION May 1979 469 DIODES/Z ENE RS SOCKETS/BRIDGES TRANSISTORS. LEDS. etc. 1N914 100v 10mA .05 8-pin pcb .20 W W .35 252222 NPN (252222 Plastic .10) .15 252907 PNP .15 1N4005 600v 1 A .08 14-pin pcb .20 WW .40 253906 PNP (Plastic - Unmarked) .10 1N4007 1000v IA .15 16-pin pcb .20 WW .40 25 3904 NPN (Plastic • Unmarked' .10 1N4148 75v 10mA .05 18-pen pcb .25 WW .75 253054 NPN .35 1N4733 5.1v 1 W Zener .25 22-pen pcb .35 NON .95 253055 NPN 15A 60v .50 T 1 PI 25 PNP Oar linglon .35 1N753A 6.2v 500 mW Zener .25 24-pin Deb .35 WW .95 LEO Green, Red. Clear, Yellow .15 1N758A 10v .25 28-pen pcb .45 NON 1.25 0.1.747 7 seg 508 - High corn-anode 1.95 1N759A 12v .25 40-pen pcb .50 WW 1.25 MAN72 7 'mg corn-anode (Red! 1.25 1N5243 13v .25 MAN3610 7 seg rom-anode (Orange) 1.25 Molex pens .01 To-3 Sockets .25 MAN82A 7 seg cons-anode (Yellow) 1.25 1N5244B 14v .25 2 Amp Bridge 100-pry .95 514574A 7 seg corn-cathode (Redl 1.50 1N52458 15v .25 F513359 7 seg corn-cathode 1Red) 1.25 25 Amp Bodge 200-pry 1.95

C MOS - T T L - 4000 .15 7400 .10 7473 .25 74176 85 74H72 .35 745133 .40 4001 .15 7401 .15 7474 .30 74180 .55 74H101 .75 745140 55 4002 .20 7402 .15 7475 .35 74181 2.25 74H103 .55 745151 .30 4004 3.95 7403 .15 7476 .40 74182 .75 74H106 .95 745153 .35 4006 .95 7404 .10 7480 .55 74190 1.25 745157 .75 4007 .20 7405 .25 7481 .75 74191 .95 74100 .25 745158 .30 4008 .75 7406 .25 7483 .75 74192 .75 74102 .20 745194 1.05 4009 .35 7407 .55 7485 .55 74193 .85 74103 .25 746257181231 1.05 4010 .35 7408 .15 7486 .25 74194 .95 74104 .30 4011 .20 7409 .15 7489 1.05 74195 .95 74110 .20 74 L500 .20 4012 .20 7410 .15 7490 .45 74196 .95 74120 35 741S01 .20 4013 .40 7411 .25 7491 .70 74197 .95 74130 .45 741502 .20 4014 .75 7412 .25 7492 .45 74198 1.45 74147 1.95 74 LSO4 .20 4015 .75 7413 .25 7493 .35 74221 1.00 74151 .45 741505 .25 4016 .35 7414 .75 7494 .75 74367 .75 74155 .65 74 LSO8 .25 4017 .75 7416 .25 7495 .60 74172 .45 741509 .25 4018 .75 7417 .40 7496 .80 75108A .35 74173 .40 741510 .25 4019 .35 7420 .15 74100 1.15 75491 .50 74174 .45 741611 .25 4020 .85 7426 .25 74107 .25 75492 .50 74175 .55 741620 .20 4021 .75 7427 .25 74121 .35 74193 .55 741S21 .25 4022 .75 7430 .15 74122 ..55 741123 .85 74 LS22 .25 4023 .20 7432 .20 74123 .35 74H00 .15 741S32 .25 4024 .75 7437 .20 74125 .45 74H01 .20 74500 .35 74 LS37 .25 4025 .20 7438 .20 74126 :35 74H 04 .20 74502 .35 741538 .35 4026 1.95 7440 .20 74132 .75 74H05 .20 74503 :25 , 741a4 4 .30 4027 .35 7441 1.15 74141 .90 74H08 .35 74604 .65 4028 .75 7442 .45 74150 .85 74H10 .35 74505 35 741S51 .35 4030 .35 7443 .45 74151 .65 74H11 .25 74508 .35 741574 .35 4033 1.50 7444 .45 74153 .75 74H15 .45 74510 .35 74 LS86 .35 4034 2.45 7445 .65 74154 .95 74H20 .25 74511 .35 741690 .55 4035 .75 7446 .70 74156 .70 14H21 .25 74620 .25 74 LS93 .55 4040 .75 7447 .70 74157 .65 74H22 .40 74540 .20 7415107 .40 4041 .69 7448 .50 74161 .55 74H30 .20 74550 .20 74 LS123 1.00 4042 .65 7450 .25 74163 .85 74H40 .25 74551 .25 7416151 .75 4043 .50 7451 .25 74164 .60 74H 50 .25 74564 .15 7416153 .75 4044 .65 7453 .20 74165 1.10 741-151 .25 74574 .35 7415157 .75 4046 1.25 7454 .25 74166 1.25 74 H52 .15 745112 .60 7416164 1.00 4049 .45 7460 .40 74175 .80 74 H53J .25 745114 .65 74L5193 .95 4050 .45 7470 .45 74 H55 .20 74 LS367 .75 4066 .55 7472 .40 74 LS3E8 .65 4069/74 CO4 .25 4071 .25MCT2 .95 LINEARS, REGULATORS, etc. 4081 .308038 3.95 LM 32075 1.65 J LM340K 15 1.25 LM 723 .40 4082 .30LM201 .75 L.M320112 1.65 LM340K 18 1.25 LM725N 2.50 MC 14409 14.50LM301 .45 1M320715 1.65 LM340K24 1.25 1M739 1.50 MC 14419 4.85LM308 (mini, .95 LM 324N 1.25 78105 .75 LM 74118-141.25 4511 .95LM309H .65 LM339 .75 78112 .75 0.1747 110 74C151 1.90 LM309K (3.10k-5)85 7805 1340151 .95 78115 .75 LM1307 1.25 LM310 85 LAA 340-712 .95 78M05 .75 1M1458 .65 9000 SERIES LM311D 'menu .75 LM340715 .95 LM373 2.95 1M3900 .50 9301 .85 95H03 1.10 LM318 (Mani) 1.75 LM340T 18 .95 1M380 (a-14 PIN) .95 11075451 .65 9309 .35 9601 .20 LM 320K 5)790511.65 LM340724 .95 LM709 ie.14 perye.25 NE555 .35 LM711 .45 9322 .65 9602 .45 LM320K 12 1.65 LM340K 12 1.25 NE 556 .85 NE565 .95 MICRO'S, RA MS, CPU'S, NE 566 1.25 E-PRO MS NE567 .95 746188 3.00 8214 8.95 INTEGRATED CIRCUITS UNLIMITED 1702A 4.50 8224 3.25 7045314 3.00 8228 6.00 7889 Clairemont Mesa Blvd., San Diego, CA 92111 U.S.A. SPECIAL MM5316 3.50 8251 8.50 No Minimum 2102-1 1.45 8255 10.50 DISCOUNTS All prices in U.S. dollars. Please add postage to cover method of 21021-1 1.75 8713 1.50 Total Order Deduct 2114 9.50 8723 1.50 shipping. Orders over $100 (U.S.) will be shipped air no charge. $35 • $99 10% 1R16026 3.95 8724 2.00 Payment should be submitted with order in U.S. dollars. 9100 • $300 15% TMS 4044- 9.95 8797 1.00 All IC's Prime/Guaranteed. All orders shipped same day received. 6301 - $1000 21078-4 4.95 20% Telex: 18691 W 8080 8.95 2.708 9.50 Phone (714) 278.4394 Barclayeard / Access / American Express / BankAmeriasrd / Visa / MasIerCharge 8212 2.95 Z80 PIO 8.50

470 RA DIO COM M UNICA TIO N May 1979 ICUJAVE n D„A___ES LITD

WHAT A FINE PAIR !!

* FEATU RES * FULLY PROTECTED AGAINST POOR LOAD * EQUIPPED WITH RF VOX AND MANUAL VSWR, OVERHEATING AND EXCESSIVE OR OVERRIDE REVERSE SUPPLY RAILS * SUPPLIED WITH POWER LEAD AND ALL CONNECTORS

SPECIFIC ATION: M ML144/100 SPECIFIC ATIO N: M ML432/100

Power Output 80 watts minimum RMS Power Gain 10dB minimum output Power Output 100 watts RMS output ® 100 watts RMS typical 1dB compression Power Input 10 watts nominal for 80 Power Input 10 watts nominal for 100 watts output watts output Frequency Bandwidth 144 148MHz @-0.5dB Frequency Bandwidth 435MHz !,15MHz @ -1dB RF Input Connector 50 ohm BNC RF Input Connector 50 ohm BNC RF Output Connector S0239 RF Output Connector 50 ohm 'N' Type Power Requirements 12 •5V nominal @12 amps Power Requirements 12.5V nominal @200mp5 for 80 watts output. 13.8V for 100 watts output. maximum. 13.8V maximum Weight 4kg 18Ib 13cal Weight 4kg (8Ib 13oz1 Overall Size 315 x142 x 105m m Overall Size 315 x142 x 105mm (14 x5¡x4r) (14 x5¡ x 4¡" Price £124 +VAT Price £220 + VAT l£13950 inc. VAT) (£24750 inc. VATI

Any further information on the above products and others from our extensive range may be obtained by contacting our sales department, who will be only too pleased to help. ALL OF OUR PRODUCTS ARE FULLY GUARANTEED FOR 12 MONTHS M I CR O WAVE M O D ULE S BROO KFIELD DRIVE, AINTREE, LIVERPOOL L9 7AN, EN GLAND Telephone: 051-523 4011 Telex 628608 MICR O G

RADIO CO M MUNICA TION May 1979 471 FOR QUALITY CRYSTALS-AT COMPETITIVE PRICES. POPULAR FREQUENCIES IN STOCK- MADE TO ORDER 10kHz to 225MHz

E1SL leads the field in supplying crystals world wide to major communications companies, broadcasting authorities and posts and telecommunications administrations. As a result we can supply the amateur with a high quality, competitively priced product over a frequency range from 10 kHz to 225 MHz. Get the power of the professionals in crystal supply behind you!

2 METRE STOCK CRYSTALS. Price £1.85 for one crystal. MADE TO ORDER CRYSTALS SINGLE UNIT PRICING £1.75/crystal when two or more purchased.

HCMLI H U M 14025/11 111:25213 HC25,1U 1106 8/ 25/U A111339384. C1 ,383,36. lot IT2iI ence Adjumment 1 tn. 464 Dellyeey 25pF and 209F And 25pF and SI sicck PUS Yeatta F7710. r geia..«.1e Gtoup tolerance Range A e 309F TX 30pf TX 110pF T-48 RX a TX 5505 FT2 Ault, FT224. TAD 2200 pm! ruo(1311 ,801.115 200 Mg en 10,u 19999111/ 123 00 3 0777 8 05,4 12 0833 14 9888 18 1250 44 9668 8041390,11:774.715138 ,35 AI 4 0284 80569 12 (454 14 9916 18 1281 44 9750 14.93,36 ru. R. to R7, 970 tu 700 00101 , 20 83 799/i) .e 116 50 30 As 999119 310 9,90 131 4 0291 80563 170876 14 9944 18 1319 444833 523 4,30 Hoe. 4 33818 Mlle rA 2001114.40 700 001311 100 tu 999 9993111 I 501 03 4 0798 0 0597 12 0895 14 9972 18 1343 44 9916 33 T1C6/U lo. 1451 MTH Icon, 1008 , 1 399 /39., 5 50 134 4 0305 0511 2 0916 16 0000 Ill 1375 45 0000 C. yarats f X end R X 1u, so 4000 IC 1 608, 1 999 MI43 13 DO 1350 R5 4 0312 8 6675 12 093/ 15 0727 18 1406 45 0083 145 25 MID ,410 400 TX 80 lo 20010 2 59,334/13 13 50 t3111 R6 4 0314 8 5638 1'0956 15 0055 18 1437 45 0166 145 6 Mlle 1013 .11 44 MM. FM is 6010 3999 MHz 13 40 13 CO 107 4 0376 80652 170974 15 0383 18 INV 45 0250 uys1.316,n /1663901.6251,8, is 40010 20999 MTN 13 35 12 95 976 4 0416 80833 12.1250 14 977/ 18 1876 44 9313 145 tond 145 IRR. - , and alC5 sil 4 0473 00941 12 17)0 14 980b 18 1906 44 9416 80,3 lot 145 476 5111: 419, lo 211/010 24 000 MK, 1D 70 13 311 3.409T 10 7100u/ 59 999 1469 13 35 .295 922 4 0430 8 0861 112 1791 49033 18 1930 44 9500 016« 3/5§1313 0., 36343 — send 511, Eil 00 to 104999 MF6 13 35 13 00 973 4 6337 8 5875 12 1312 14 9861 18 1968 44 9583 .331/0 035818 ovt 10 1050010119999 P.Me e 500 (4 85 516.716 ,15639,091 20 120 Dew 149 999844 1600 2 METRE MADE TO ORDER CRYSTALS at £2.50 (No discounts) is 20 156 00 to 225 MO M 10- USO This service is designed specifically for those customers who require an odd S channel or Raenet crystal and covers most ex•com mercial and Japanese equipments. TX4 to 4.06 MHz. 6 to 6.084 MHz, 8 to Unlessotherwise requested fundamentals will be supplied with 30pF 8.12 MHz, 12 to 12.17 MHz and 18 to 18.25 MHz. RX 10.25 to load capacity and overtones for series resonance operation. 10.4 MHz, 11.1 to 11.28 MHz, 14.81 to 15.04 MHz, 44.43 to 45.1 MHz and 51.56 MHz to 52.24 MHz. Delivery 6 to 8 weeks. Holders HC6. HOLDERS — Please specify when ordering — 10 to 200 kHz HC13/1.1. HC18 or HC25/U. When ordering please give crystals load capacity 170 kHz to 170 MHz HC6 or HC33/U, 4 to 225 MHz, HC18 and HC25. and holder. Specify equipment in which crystals are to be used. DELIVERY Column A 3 to 4 weeks. Column B 6108 weeks. 4 METRE CRYSTALS for 70.26 MHz in HC6/U at £2.25. TX 8.78250 MHz RX 6.7466 or 29.78 MHz in stock. DISCOUNTS 5% mixed frequency discount for 5 or more crystals at 8 delivery. Prrce on application for 10 or more crystals to same 70cm CRYSTALS frequency and specification. Special rates for bulk purchase Crystals held in stock for Pye Pocketfone PF1 for SU8(433.2 MHz) and schemes including FREE supply of crystals used in UK repeaters. all UK repeater channels R80, 2. 4, 6, 10 and 14 at £4.50 a pair or TX only £2.25. RX only £2.50. Also 8.0222 and 12.0333 in HC6/U for SU8 EMERGENCY SERVICE SURCHARGES (to be added to A delivery at £1.85. We can supply crystals in 6 to 8 weeks for any frequency prices). 4 working days E8, 6 working days [6, 8 working days £4. 13 within the 70cm amateur band for Pye,W15U, U108, U450L and FDK working days £3 (maximum of 5 crystals on 4 day delivery). Multi U 11 at £2.50 per crystal. CRYSTAL SOCKETS HC6/U and HC25/U 16p CONVERTER CRYSTALS in HC18/U at C2.85. In stock. 38.666, 42.000, 70.000, 96.000, 101.000, 105.666 and 116.000 MHz in MINIMU M ORDER CHARGE El.50 stock. COM MERCIAL USERS. Crystals can be supplied lor MPU, industrial TONE BURST AND I.F. CRYSTALS in HC18/U at £2.25. in stock. control etc in the range 4-21 MHz fundamental and 3rd OVT 18 to 7.168 MHz for 1750 kHz and 10.245 MHz for 10.7 MHz IF's. 60 MHz at £1.15 for 100 off. This is only a limited example of our capabilities. Please enquire about other quantities, frequency ranges. FREQUENCY STANDARDS (8% VAT) In stock. watch and sub-carrier crystals. We can supply crystals for marine and 455 kHz, 1 MHz, 5 MHz, 10 MHz in HC6/U Price E2.75, 10.7 MHz in land mobile radio telephone use. Send for details. HC18/U Price £2.75, 100kHz in HC13/U Price £2.50 (special offer) TER MS. Cash with order, cheques and postal orders payable to OSL Ltd. All prices include postage to UK and Irish addresses. PRICES ARE EX VAT PLEASE ADD UV.% UNLESS OTHER WISE STATED OVERSEAS DISTRIBUTORS. West Germany. Austria and Benelux countries — SSB Electronic, fuartSLab MARKETING LTD Karl Arnold Str 23,5860 Iserlohn, West Germany. P.O. Box 73 Denmark — Asbjorn Jorgensen, Aabrinken 1, Tapdrup, DK800. FORMERLY C&C ELECTRONICS London SE18 3LR Denmark. Portugal — Sorubal SARL. Rua General Pimenta de Castro. 15-81. Telephone: 01-690 4889 24HrAnsafone: 03224 30830 Lisboa 5, Telex: 912881 CWUKTX-G (Attention QUARTSLAB) Cables: QUARTSLAB London SE18 (Enquiries invited from companies in other countries).

472 RA DIO CO M MUNICATION May 1979 D ATO N G ELECTR O NICS Iii LIMITE D r MORSE TUTOR

% 111 The revolutionary new way to practice morse Model 070 itik IS R code reception. The DATONG Morse Tutor gives you rnan unlimited supply ofprecision morse at the tu of a switch, PLUS built-in oscillator for sending practice. Now, you can practice receiving morse whenever, and wherever, you like. The DATONG MORSE TUTOR sends a continuous stream of precision morse in five character groups which never repeat. For optimum learninq efficiency it has a calibrated variable speed control plus a separately variable delay facility between characters. It delivers letters only, numbers only, or mixed letters and numbers. It comes with a built-in tone oscillator for sending practice (key required), built-in loudspeaker, and also a separate earpiece for private listening. Learn morse, the easy, convenient and self-pacing way with the DATONG 070 Morse Tutor. Supplied complete with battery for only £37.00 plus VAT giving a total of £41.62.

Model ASP Automatic R.F. Speech Processor Model UC/1 Up converter -

Our R.F. Speech Processors, using the advanced technique of R.F. clip- If You already own a good quality ten-metre or two-metre receiver or ping, greatly increase your talk power and help your voice punch through transceiver you are only £118 away from a really high performance general the ORM. coverage receiver. just add the magic ingredient. MODEL UC/1 from They work on any rig, with any speech mode, at any power level, and on DATONG' any band. Simply connect in aeries with your microphone to get a really You get full coverage in thirty synthesised 1MHz segments from 60kHz punchy speech signal. MODEL ASP, our latest model, offers for the fire (Rugby MSF) to 30MHz, at high sensitivity and with all the facilities and time the ultimate convenience of instant push-button selection of the high performance of your existing rig! desired amount of clipping and elimination of manual level setting. For good measure UCi1 also adds two-metre coverage to ten-metre Prices: ASP £65.00 plus VAT 1f73.13 total); RFC £10.00 plus VAT 1(46.00 receivers. total): RFC £2150 plus VAT 1E24.19 total!. Price f 105.00 plus VAT (£118.13 total I.

Model FL1 Frequency Agile Audio Filter Model AD170 Active Antenna

A versatile add-on unit for communications receivers which helps to ex- For sensitive reception right through from MSF at 60kHz to Sand 1 TV DX tract wanted signals from background interference. It connects in series around 50MHz, without the need for an antenna farm, MODEL AD170 is with the loudspeaker or headphones. The effect is similar to "IF. pass- ideal. Designed for loft mounting, MODEL AD170 has no adjustments and band tuning" for SSEItor RTTY reception, and bandwidth down to 20Hz needs no external tuning units. with limited a.f.c.) gives an amazing capability for pulling weak CW sta- Although only three metres long. MODEL AD170 has the same directional tions out of the ORM. MODEL FL 1 is unique in being able to tune itself properties as a full size dipole, even at 60kHz. when notching out unwanted whistles. Price: £29.50 plus VAT 1E33.19 tote; Special price complete with mains Price: M OO plus VAT 106.63 total/. power unit: f33.00 plus VAT 1(37.13 total). ,

ELE CTR O NICS LIMITE D Spence Mills, Mill Lane, Bromley, Leeds LS13 3HE, England. Telephone: (0532) 552461

RADIO COM MUNICATION May 1979 473 A MATEUR RADIO Net e • _art et% EXCH ANGE

Proprietors: Brenda Aptaker, Bernard Godfrey (G4A0G) lie e You've read all the advertisements and you've chosen the new rig you NEED to buy. Before you decide WHERE to buy it, be sure to phone 01-579 5311 Discuss your requirements with us. Come in and try the equipment. That way you'll know that what you're investing in really is right for you. So buying, selling or just browsing come to the shop where they CARE. And have a cup of Brenda's coffee as well! Or see us on our Stand at the major Sum mer Rallies.

YAESU-MUSEN ICO M

CPU250OR FR-101 Fr -7B IC-215 portable 2m FM Tx Ax 25W 2m Transceiver Series 160-2m Ax 100W PEP HF TX IC-202 portable SSB 2m Tx CPU250ORK FT-101E FP -12 Ax 25W 2m Transceiver Transceiver 160-10m 10 amp Power supply IC-402 70cm portable SSB CPU250ORS Fr-101Z for above Transceiver 10W 2m Transceiver Transceiver 160-10m FL- 110 IC-240 synthesised 2m FM CPU250ORKS F7-101ZD Linear for above Transceiver 10W 2m Transceiver Transceiver 160 - 10m FP -4 IC-280E synthesised 2m FM F7-202R !digital readout) AC Power Supply Transceiver digital hand-held 1W FT-200 12v out plus memories Transceiver Transceiver 160-10m Fr- 225 IC-701 HF Transceiver FRG-7 FT-227R Series 2m FM/AM/ IC-245E FM/SSB 2m Tx Rx General Coverage Tx 2m with 1MHz scan SSB Transceiver IC-211E All mode 2m Receiver FT. 901 Fr- 301 synthesised Tx Ra FRG-7000 Series (all models) Series HF Transceiver IC-R M3 Remote control Digital General FT-7 FL- 21008 micro-processor Coverage Receiver 10W mobile HF Tx HF Linear Amplifier keypad

FDK K W Multi 800D and 700E MICRO WAVE MODULES and QM 70 25W FM synthesised E-Z Match Full range of converters, transverters, counters, 2m transceivers 107 Antenna Tuning pre-scalers, linear amplifiers, etc. Quartz 16 System 2m FM transceiver 109 Antenna Matching Multi U11 System A.S.P., BANTEX, G-WHIP, HY-GAIN, 70cm transceiver thigh power) JAYBEA M, MOSLEY, PANORA MA TM56B Dum my load 2m monitor receiver Antennas, beams, whips, rotators. etc. with scan

SPECIAL FOR ALL FRG-7 OWNERS PHONE FOR DETAILS

Modification kits for narrow-band SSB filter now available, com- OF CURRENT STOCKS AND PRICES, plete with simple step•by-step instructions. £15.00 inc p&p. NEW AND SECONDHAND

CLOSED WEDNESDAY, BUT USE OUR 24 HOUR ANSAFONE SERVICE

I , .1 EASY TERMS UP TO CREDIT SALES INSTANT HP FOR VISA 2 YEARS AIL BY TELEPHONE . . LICENSED AMATEURS So easy for Overseas Visitors—just seven stops from Heathrow— or phone your order and let us deliver it to you at the Airport.

2 NORTHFIELD ROA D, EALIN G, LON D O N W13 9SY. Tel: 01-579 5311

474 RADIO COM MUNICATION May 1979 PROFESSIONAL P . M ELECTRONIC * COMPLETE SERVICES AMATEUR CRYSTAL SERV ICE *

VAT-PRICES EXCLUDE VAT; FOR YOUR CONVENIENCE THE VAT INCLUSIVE PRICE IS SHO WN IN BRACKETS OVERSEAS ORDERS (Inc. Eire and Channel Isles) NO VAT CHARGEABLE. CRYSTALS FOR THE BRITISH 70CM CHANNELS 2M TX Et RX CRYSTAL AVAILABILITY Et PRICE CHART Due to the much higher multiplication involved (3 times that on 2m) all our stock 7 m crystals are to much closer tolerances than our standard amateur range. CRYSTAL We are stocking the following channels ROO 1434•60/433. 001, RB2 FREQUENCY (434• 66/433.051, RB4 (434 • 70/433-10), RB61434• 75/433 • 15), SU8 (433-201. R810 RANGE 71 71 1434•85/433•25), RB14 (434•95/433.35), SUI8 1433.451 end SU20 1433•9)/- TX USE (TX or , a e = = e. and RX for use with: PYE UHF Westminster 1W151.1), UHF Cambridge 1U10131, and HOLDER; I 1 g 5 g Q rg y.e Q y g y pg Pocketfone 1PFU and STOR NO COL/COM 662 all at £2.32 1E2.811. For the U450L e c età MCe cC ee e e M Base Station we have the TX crystals for all the above channels 12.32 ((2.61). The 0 U e & e e e RX crystals for the U450t. Base Station, together with the TX and RX crystals for the FR EQUENCYTPUT O f 11.4 7: a 3 3 Â 4 4 4 à $ remaining SU channels 1SU12 - 433•30•RTTY, SU16-433-40and SU22-433- 551 for all the above equipments are available at £3.92 1E4.411 to amateur spec or £4.64 144.4 1433.2) b e b e b e 1E5.221 to same spec as stock items. Delivery approx. 4/5 weeks.

144.493 e e e e 01 e 144.800 e e c c 4m CRYSTALS FOR 70.26MHz 144.850 e e T X8. 71325MHz and 11X6 • 7466MHz or 29. 7800MHz 12.32 1E2.611. 145.000/ROT c a 10.246MHz "ALTERNATIVE" I.F. CRYSTALS- U.32 1E2.611. For use in Pye 146.025/R1T e a and other equipment with 10-71V1Hz and 465kHz I.F.s to get rid of the 'birdy" just

145.050/R2T e a ebeecons above 145-0MHz. In HC6f1.1, HC18/U and HC25/U. 145.075/R3T e a CRYSTAL SOCKETS- HC8/U. HC13/U and HC25/U (Low loss) 16p each 145.100/R4T e a 118p). 10p P. Er P. per order (P. Er P. free if ordered with crystaLs). 145.125/R5T e a CONVERTER/TRANSVERTER CRYSTALS- HC18/U 145.150/R6T e a All at £3.00 (£3.37), 38•6666MHz (144/28), 42MHz 170/281, 58MHz 1144/281, 145.175/1171 e a 70MHz (144/41, 71MHz (144/2), 95MHz (342/521, 96MHz 11,296/432/1441, 101MHz 145.200/REIT e a (432/28), 101•50MHz 1434/281, 105•6666MHz 11,296/281 and 116MHz (144/213). 145.300/S12 e e e CRYSTALS MANUFACTURED TO YOUR SPECIFIC REQUIREMENTS 145.350/S14 e c c Prices shown are for one off to our amateur specs; closer tolerances are available. 145.400/S16 e e e Please send us details of your requirements. 145.4251S17 e e e A Low frequency fundamentals in HC13/U or HC6/U 145.450/518 e e e 0 00000 CD 0 0 CD CD Adj. toi. ±5Oppm Temp. to). ±100ppm 0 to + 70"C

145.475/S19 e e a 0 6.0 to 19•999kHz £28.12 1(31.63) 80 to 99•999kHz £7.30 1E8.211 145.500f $20 c a b 0 145.525/521 c a b 20 to 29•999kHz £17.75 ((19.97) 100 to 14.9•99kHz -.£6.68 1E7.511 145.550/S22 c a b 30 to 59•999kHz £15.61 (£17.45) 150 to 499-99kHz £6.20 1E6.97/ 145.575/S23 c a b 60 to 79•999kHz £12.41 ((13.19) 500 to 799•99kHz £7.30 1E8.21) 145.600/ROR c a b B Mid frequency fundamentals in HC6/U. HC1111/U or HC26/U

Crl7crcrecr co. O mnocroceemOOOCTOneDO] 145.625/R1R mnocroceemOOOCTOneDO] O co. e e Crl7crcrecr e Adj. tol. ±2Oppm Temp. tol. ±3Oppm -1010 • 60°C -

145.650/R2R c e o e f800 to 993•91tHz.... £9.150 1E10.641 *04.0 to 5•999MHz £4.24 (E4.771 - 145.675/R3R c e e *T1 •0 to 1•499MHz....1111.40 (€10.571 • 643 to 20•99MHz £3.92 1E4.411 145.700/R411 c e e .1-1 -5 to 2 • 599MHz.... £4.24 1E4.771 ' 21 to 24 •99MHz £6.48 1E7.291 145.725/11611 c e e •-1-2•6 to 5 • 999MHz.... £3.92 1E4.411 25 to 27-99MHz f8.88 (E9.99) 145.750/11611 c e e • a • 4 to 3. 999MHz £4.96 1E5.581 28 to 30MHz £9.68 (£10.891 145.775/R7R c e e C High frequency overtones In HC6/1.1. HC18/LI or HC25/U

145/800/R8R eracrerwa c a a Adj. toi. ±2)pprn Temp. tol. ±3Oppm -1010 +60°C

145.950/S M a e e aionnonnnnnnn l • 15 to 20•99MHz 13 0/7) £424 (E4.77) Prices: le) £1.96 1(2.19), lb £2.32112.511 10E2.80 ((3.15), dl and le) £3.92 (£4.4)) 21 to 63MHz (30/T1 £3.92 (E4.41) AVAILABILITY: a), (b), (cl and Id mock items normally available by return (we 60 to 62.99MH:150/T) £4.88 (E5.49) have over 5000 items in stock). (el Four weeks normally bu it is Quite possible we '63 to 105MHz 16 0/71 £4.48 (E5.04) could supply from stock. N.B. Frequencies as listed above but in alternative holders ▪ 10610 125MHz (50/71 £5.134 1E6.671 and/or non stock loadings are available as per code 126 to 180MHz £6.48 (C7.29) ORDERING: When ordering please quote (I) Channel, (21 Crystal frequency, (3) 160 to 250MHz £10.54 it 11.86) Holder, (4) Circuit conditions hoed In p1). If you cannot give these, please give make 'Delivery Normally 4/6 weeks (express available) -all other frequencies 6/8 weeks. and model of equipment and channel or output frequency required and we will ad- Holders-Low frequencies HC13/U or HC6/U dependent on frequency. vise if we have details. Mid and High frequencies are available in HC6/ U, HC18/LI or HC25/U unless marked only available in HC6/U or p only available in HC18/U and HC25/u. JAPANESE AND AMERICAN EQUIPMENTS HC17/U (replacement for FT243) and HC3311.1 (wire end HC6/U/ available as per We can supply crystals for YAESU FT2F. FT2FB, FT2 Auto, FT224, most of the HC6/U above at 26p 128p) extra on HC6/U price. ICO M range and the TRIO-KEN WOOD range. We can also supply from stock Unless otherwise speeded, fundamentals will be supplied to 30pf circuit conditions crystals for the HEATHKIT KVV202 and HW17A. and overtones to series resonance. YAESU FT221 CRYSTALS NOW IN SlULF., ALL AT £2.110 ([3.15). AH popular TEST EQUIPMENT FREQUENCY STANDARD CRYSTALS channels-For repeater use advise xte) frequency required as earlier models have 100kHz in HC13/U and 455kHz in HC6/U, 12.36 1(3.19). different shift stale to later FT221R. We can also supply the crystal to give NORMAL 1MHz and 5MHz in HC13/U and 10MHz and 10-7MHz in HC6/U and HC25/U. E2.80 "tune to RX" working as FT22111. 1(3.02). BURNS ELECTRONICS We are the Northern Appointed Agents for BURNS KITS etc. and can supply many CRYSTALS FOR PROFESSIONAL USE of their products from stock. We can supply crystals to most commercial and MIL specifications, with an express service for that urgent order. Please send S.A.E. for details or telephone between MODULAR COM MUNICATIONS SYSTEMS 4.30-7pm and ask for Mr. Norclitfe. For the RTTY enthusiast we can recommend and supply the "MCS" range of products. This includes terminal units. AFS keyers. magnet drivers for TTL interface, CRYSTALS FOR LARGE QUANTITY COM MERCIAL USERS telegraph distortion measuring adaptor. RTTY audio processor, power units. etc. We can supply crystals for commercial use, e.g. TV or computer crystals, etc. at For the CW man we have the "MCS" CW filter which gives three stages of active very competitive prices. Please let us know your requirements filtering. Please send S.A.E. for full details of the "MCS" range. EXPRESS SERVICE ANZAC MD-108 DOUBLE BALANCED MIXER Many types of made-to-order crystals are available on our "EXPRESS 5-503MHz supplied with full details for only £5.95 1(6.43). SERVICE"- with delivery of three days on our class "A" service. Telephone or MICROCOMPUTER DIVISION Telex for details. We are now suppliers of popular Z80 based microcomputer systems including "DYNABYTE" and "North Star HORIZON" together with a full range of VDUs TERMS: CASH WITH ORDER- MAIL ORDER ONLY-S.A.E. WITH ALL and line printers. We can supply either as basic units or as complete working ENQUIRIES- PRICES INCLUDE P. Er P. 18RITISH ISLES) EXCEPT WHERE systems with software for the smell business user. STATED- OVERSEAS CHARGED AT COST.

2 ALEXANDER DRIVE, HES WALL, WIRRAL, MERSEYSIDE, L61 6XT Tel: 051-342 4443 Cables: CRYSTAL. BIRKENHEAD. Telex: 627371

RADIO COMMUNICATION May 1979 475 S.E.M. P.O. BOX 6, CASTLETO WN, ISLE OF MAN, TEL. MARO WN (0624) 851277 S.E.M. EQUIP MENT NO W FOR THE EIGHTIES

THE SENTINEL 2 METRE PRE-A MP circuit was designed in 1969 SENTINEL 2 METRE POWER AMPLFIER /PRE-A MPLIFIER employing the then up to the minute technology of FETs. The quali- The transmit amplfier now uses the latest type of internally match- ty of the design is shown by the sales increasing steadily for a ed, mismatched protected transistor, which provides four times decade and now being higher than ever. What other equipment sells power gain le. 12W IN, 48W OUT. It uses an ultra linear circuit for more now than ten years ago? The only changes made to the circuit use on all modes. The receive pre-amplifier is the same as the Sen- have been different FETs to keep up with the latest improved low tinel above. The package is completed with an r.f. switch, with time noise and higher reliability devices. Then the r.f. switching and pro- delay for SSB use, which can be operated by the transceiver. Size: tection circuits were incorporated to produce the "AUTO"- units. 6" x 2' front panel, 4}" deep. Price: £69.62. Ex-stock. Without the Another original idea, first on the market and an immediate success. pre-amp, £49.50. Ex-stock. Yes, they do work fine with FT221s and The point of all this is that, over the last year we have developed a TS700s. new range of 70cm and 2 metre pre-amps ready NOW for the eighties, so place your order. SENTINEL H.F. WIDEBAND PRE-A MPLIFIERS 2 40MHz. 15dB gain. Ideal units for pepping up receivers on 15 and 10, for OSCAR reception and as an ACTIVE aerial.

litre Sortüreetfiadi SENTINEL STANDARD H.F. PRE-A MPLIFIERS —Performance .11/ INV • M R .,. as above. Price: £9.00 Ex-stock.

SENTINEL AUTO H.F. PRE-A MPLIFIERS Same performance as above with a changeover relay operated by your transceiver relay for direct connection in your aerial co-ax. Price: £12.94. Ex-stock.

NEW! Our Forward/Reflected power meter designed for British

power levels, F.S.D. 500W. scale 100W, rtf, scale 1W. 1-30MHz. The pick up unit with two S0239s is 2" x2" x I -;-" and connects in the aerial lead. The meter unit is a separate box 61" x31" panel, 21" deep, which you can put in any convenient position. Price: £28.50 Ex-stock.

SEM Z MATCH The updated unit uses much more reliable slow motion drives; which make adjustment and resetting easy. It will match aerials of 15-5000 Ohms, to your equipment. BALANCED or UNBALANCED at up to IkW. S0239 and 4mm terminals for co-ax or wire aerials. Price: £39.44. Ex-stock.

The most popular 2 metre transverters: SEM EUROPA C 2 METRE TRANSVERTER — 200W INPUT. 2dB Noise figure. Plugs straight into Yaesu equipment for any mode 2 metre operation. Price: £112.50. Repeater shift if required for F.M. £12.50. INCREASE YOUR 2 METRE RANGE Our Sentinel range of pre-amplifiers use a J FET rather than the SENTINEL MOSFET 2 METRE CONVERTER usual MOSFET because they give lower noise figures. They are I.F.s: 28-30MHz, 4 -6MHz, 2 -4MHz. N.F. 2dB, Gain 30dB. Price: selected for a ldB noise figure. We also stock these units on Marine £20.25. Satellite and Marine Band also in stock. Band and Satellite Band and on other frequencies to order. SENTINEL X 2 METRE CONVERTER —Same as above with A.C. SENTINEL AUTO 2 METRE PRE-A MPLIFIER power supply. Price: £24.75. Ex-stock. Connects straight into transceiver aerial feeder and the r.f. switching SEM 70 70cms to 2 metre converter. Price: £20.25. Ex-stock. looks after the changeover. Gain is 18dB. Any transmit mode. Price: SENTINEL 70 70cms to 10 metre converter. Price: E22.50. Ex-stock. £17.35. Ex-stock. 70cms version is £20.25*. Ex-stock. SENTINEL TOP BAND CONVERTER Price: £20.25. Ex-stock. •S0239 sockets available on these units at an extra cost of £1.69. SENTINEL STANDARD PRE-A MPLIFIERS Same as above but without the automatic r.f. switching. 2 metres is £10.85. 70cms is £13.50. BOTH IN STOCK. Circuits and instructions provided with equipment. All prices include VAT and delivery. THE ORIGINAL PA3 PRE-A MPLIFIER For more details of any of our equipment, please ring or write. Size 1 cu. inch to fit inside your transceiver. Gain 18dB. N.F. 2dB. 12 months guarantee. To order: C.W.O. or credit card. Just phone Price £6.80. PA3/70 70cms version £9.00. Ex-stock. your credit card number for saine day service.

SEE OUR EQUIP ME NT ON STA N D R8 AT THE ALEX A N DR A PALACE EXHIBITIO N.

476 RA DIO CO M MU NICA TION May 1979 ANTENNA SPECIALISTS UK LIMITED

The widest choice for the discerning amateur For further information regarding the Antenna Specialists range some of our A mateur stockists are listed belo w:

rhanet Electronics, Herne Bay, Kant 02273 63859 Lee Electronics. London 01-723 5521 waters Er Stanton, Hockley, Essex 03 704 6853 Amateur Radio Exchange. London 01.579 5311 The Amateur Radio Shop, Huddersfield 0484 20774 C B. Electronics. Wigan 0942 216567 Leeds Amateur Radio 0532 452657 Commercial Communications, Luton 0582 21884 EleCtrosearch Ltd. K9 Building, Wapping Road. Bristol 0272 20483 Catronics Ltd, Wallington, Surrey 01-669 6700 J. Batten. 25 The Strait. Lincoln Lincoln 20767 Charnwood Communications, 44 Rathy Lane, Markfield. Leicester 05305 2585 Crayford Electronics. 6 Lovelace Close, West Kingsdown, Kent 047485 2577 Stephens James Ltd. 47 Warrington Road, Leigh. Lancs 0942 676 790 Appleton Woods Ltd, Electronics Division, 313 Heeley Road. Se:1y Oak. Birmingham .. 021 472 7485 Marcia Radiotelephones. 7 Commercial Road, Hereford HR1 286 0432 67864

Amcom m Services. 194A Nonholt Road. South Harrow, Middx. 01-864 1106 ,1

ANTENNA SPECIALISTS UK LIMITED Bandet Way, Thame Industrial Estate, Thame, Oxon OX9 3SS Tel : 084 421 3621/2

THE SUCCESSFUL MINITENNA NUNSFIELD HOUSE, COM MUNITY ASSOCIATION MONOBAND MINI-BEAMS AMATEUR RADIO GROUP: G3EE0, G3ZBI, G8KGC present the Tenth ARE BACK!! MJ.7 15 metre two element £38.75 MJ.5 10 metre two element £32.51) ELVASTON CASTLE Dural construction, low swr, lightweight and small enough for almost any CLTH, with excellent MOBILE RADIO RALLY performance. Sunday 10th June 1979 Please send S.A.E. for illustrated leaflet and full details. Elvaston Castle countryside park —showground G3XKF MINITENNA BEA MS J. SHARRATT 5 miles S.E. of Derby on the B5010 (sign-posted) Honeysuckle Lodge, Mentmore, Leighton Buzzard, Beds LU7 ORG Tel: Cheddington (Bucks) 661390 (Cheques payable to J. Sharrattl OVER 50 TRADE STANDS

TMP Many attractions for all the family. I.B.A. Oracle demonstration, side shows, childrens' rides, ELECTRONIC SUPPLIES com munications display by TAVR, and much more Specialising in Amateur Radio Equipment, we can offer all Yaesu GIANT BRING Et BUY STAND equipment from stock with 2 year warranty Et free Securicor carriage if required: full range of Amidon Toroidal Cores and Balen R.S.G.B. BOOKSTALL Kits; VV2AU Baluns Et Quad Spiders: Nye-Viking Morse Keys Et Low Pass Filters. All imported directly, plus all other items, coax, REFRESH MENTS rotators, antenas, etc. Guaranteed personal attention of PRIZE DRA W GVV3TMP with every query or sale. Telephone or write enclosing SAE for lists of prices of all items. TALK-IN by GB2ECR on 144 and 432M Hz FM Further information: I. Cage, G4CTZ BRITANNIA STORES. LEES WOOD, MOLD, CLWYD CHT ASO Tal: Pontybodkin 846 1035287) 25 Petersham Drive, Alvaston, Derby DE2 OJU Open daily 9.30 -5.00. Early closing Tues Et Sat 1pni. Tel: (0332) 71875

RADIO COMMUNICATION May 1979 477 STEPHENS-JA MES LTD G3MCN 47 WARRINGTON ROAD, LEIGH, LANCS WN7 3EA TEL 0942-676790

TRIO Monitor. 12v DC operation HY-GAIN

T S820 Transceiver £758.00 80-40 ,20 metres 6 Pole crystal filter 12AVO Vertical 10 15 20m £42.18 TS820S Transceiver £899.00 Complete with Microphone and Mobile Bracket 14AVO/WEI Vertical 10 15 20 40m £59.06 R820 Receiver £341.00 Due to deem importation from USA we cannow 113AVT,'WB Vertical 10 through 80m £85.50 SP820 Speaker £41.00 offer these at £360.1 5-band model available shortly. Th3MK3 Tnband Beam £176.62 TS5.20S Transceiver £575.00 SX R30 Carriage £2,00 on antennas SP520 £19.00 New model solid state receiver SWAN. SM220 Monitorscope £251.00 10 .MX Solid state Tx AT200 Antenna Tuner £99.00 550 041 to 30MHz £175.00 £518.00 PSU -5 AC Power Supply AORC £140.00 TL922 Linear Amphi or £826.00 3500 Digital Transceiver TS 120V Mobile Transceiver £435.00 AH240-800 channel 2m FM Hand-held £550.00 35013 Transceiver £480.00 PS20 AC PSU for TS120V £56.00 Transceiver £1915.00 TS700S All mode VHF Transceiver £637.00 MICRO WAVE MODULES STABILISED POWER SUPPLIES (New Range) SP70 Speaker £22.00 Transverters Mode 1220 15V dc 2.5Amp £3.75 TR7I01 SSB VHF Transceiver £1133.00 M MT432/28-S £133.88 Mode 122S 12-6V 2- 5Amp £18.00 197400A 2m FM Transceiver £366 00 M MT432/144-R £169.88 Mode 12512V 5Amp £24.00 TR7500 2m FM Transceiver £235.00 M MT144/28 . £88.88 Mode 153S Dual Meter 4 15V 4Amp £26.73 TR23002m FM Portable Transceiver £195.00 M MC144 any IF £20.25 Mode 156S Twin Meter 4 15V 5Amp £35.00 TR8300 70cm FM Transceiver £267.00 M MC144 /28 LO £22.50 Mode 1210S Twin Meter 4 20V 10Amp £80.00 TR3200 70cm FM Portable Transceiver £196.00 M MC70/any IF £20.25 Max. rating quoted R303 General coverage Receiver £186.00 M MC70/28 LO 122.50 Full range of crystal, microphones, plugs, psu, etc. M MAI 44 Preamp £14.63 TECHNICAL ASSOCIATES RX Band Pass filter £29 75 YAESU M MC432 any IF £27.00 M MCI 296 any IF £28.00 FIX Peak and Notch filter £29 75 FRG7 Receiver £210.50 Audio Compressor £28 75 MA/10050 /500 £69 00 FRG7000 Receiver £367.80 Preselector MK1 with relay £29.75 TH55 Headphones £9.85 N.0.1. Preselector MK2 for SIAL £26 55 SP 10113 Speaker £19.65 HC140025 watt 2m Transceiver .. POA Crystal Calibrator 121 85 DRAKE New Model VHF tunable Pre-Amu £22.50 SSR-1 Solid state receiver ms.ce JAYBEA M These prices include VAT and postage C5 2M Glass -libre coliner £34.87 TV3300 Low Pass Filter £18.00 £11.25 NEC MN7 Antenna Matching Unir £123.75 8Y/2M 8 element Teel 5Y/2M 5 Element 'reel £8.66 CD P700 Gen Coverage RX £220.00 TR7 Solid State Transceiver £999.00 PBM10 a m 10 element Parabeam £28.75 R4C Receiver £496.00 MINI PRODUCTS PEINI14/2m 14 element parabeam £36.65 T4X Transmitter . £496.00 C410 -15 20m vertical 430 Full range of antennas for 144MHz. 70cm avail- Er4.501 HQ1 Mini-Beam £ STE MILAN able with full range of tubing. clamps. etc SEND AR 10 28-30MHz AM- SSB Receiver SAE for full details SWL TUNING UNITS module . £39.50 Carriage £2.50 on Antenna Range. AA1 Audio ampliher for ARIO 14 75 MK2 Covers 550Khz to 30MHz £25.00 Designed and manufactured by as Fifty swuch• A04 FM Orscriminator £5.00 BARLO W WADLEY able tunable positions, writ march any antenna to AR20 FM Crystal controlled XCR • 30 Ru £150 your receiver Now in use in over 40 countries receiver module £50.00 XCR 30 FM Rx £170 Ideal for use with ORP transmitters. Price includes AT23 FM Crystal controlled transmitter £50.00 VAT and postage on this unit. AG10 Tone burst unit £4.50 F. D .K. AL8 10 watt Linear amplifier .. £27.00 TM560 VHF Monitor Receiver £105.00 SECONDHAND EQUIP MENT ARAC 102 2 band Receiver £100.00 PALM II Hand Held Transceiver £149.00 Due to the fact that our secondhand equipment ARAC 170 70cm and 10m Receiver £127.00 700E 2m Transceiver £229.00 stock changes daily and our adverts are in press ROTATORS weeks before publication we are not publishing a STATION ACCESSORIES (including postage) AR40 153.44 KPR400 £97.00 list. A.S.A.E. will bring you an up-to-date Irst or Single Meter SWR Wall Type C044 £106.87 AR22FI £48.38 please phone. Good clean equipment wanted and Single Meter SWR Desk Type £10.45 HAM2 £145.12 0117530 £106.75 spot cash will be paid. All secondhand egurpment Twin Meter Desk Type £12.50 carries a three month guarantee. 0-Whip Mobile antenna range 2 Way heavy duty Antenna switch £11.95 Tnbander helical 10. 15• 20m £21.15 2 Way Antenna switch £4.50 Shop Hours: Mon to Fri 9.30am to 5.30pm LF Coils for tribander £6.17 4 Way Antenna switch 16.00 Saturday 9.30arn to 4.30pm Telescopic for coils £2.70 3 Way Antenna switch £8.00 ACCESS and Barclaycard facilities Basemount standard £3.82 6 Way Antenna switch £17.25 HP terms arranged Part exchanges always wel Basemount swivel type 15 34 HyMound Morse Key £10.00 come Good clean equipment bought for cash Flexiwhrp basic 10m £14.62 Hansen) FS301 through Line Wattmeter £33.25 hems sold on a commission basis Coils for flex, £6.17 HP3A Low Pass Filter E3.00 We are located on the A574 Turn at the Grey ALOA 103 Plastic antenna inselators 23p hound Motel on the A580 (East Lancs Road) and we are about -mile on right No parking problems New model Solid State Transceiver Nye King 003 Morse Key £8.75 250 watts PEP/250 watts CW with hure in CW Standard type Morse Keys £3.15 at any time

VARIABLE CAPACITORS 25 + 25 + 25Pf @ 75P• 5Pf @ 75p. " COIL FOR MERS with core @ 6 for 25p. 2 GHz NPN STRIPLINE TRANSISTORS @ El. SSTV - RTTY GUNN DIO DES @ f1.65; AF 239 @ 50p, BEY 90 @ 50p, Printed circuit boards available for both modes. SSTV Pre. 2N 5180 @ 50p. 2N5179 @ 50p. 8E362 @ 25p. 10.7 MHz FILTER -1- 7.5kHz @ LS. 3819T @ 20p. amps, AFSK Osc units, Power supply boards. Fully built ter- ERIE REDCAP -010 100 wv @ 5p. 40673T @ 33p. minal units with all active filters. Try our new model THE BLUE LINE 2090. All ready to drive your printer_ Wired and tested terminals to drive your G3PLX video unit, direct interface. WOL MD SStv keyboard pc boards in stock, ASCII in SSTV video out. In- Please add 20p for post and packing terested drop us a line, SAE please. on U.K. orders Phone us if you prefer; evenings on the numbers below. under (2. at Overseas orders at 600 MHz 8 DIGIT FREQUENCY COUNTER cost. M. K. PRODUCTS Sensitivity 200 M volt @ £115. VAT PAID. 2 Salters Court, Gosforth, Ne wcastle-upon-Tyne NE3 5BH J . Elm THE STR AIT, KErr Gosforth 843028; Ne wcastle 843028; Jarro w 898239 Tel: 20767

478 RADIO COMMUNICATION May 1979 'l ane Wite

/ e>

DECCA-K W107 SUPERMATCH DECCA-KW - Antenna Tuning System Incorporates E-ZEE Match, SWR/RF power meter: Dummy Load: ANTENNA SWITCH Selects upto1 3 — Antenna switch. Antennas. Low- DECCA-K W109 SUPERMATCH insertion loss up o DECCA • A High power version of the KW107 is available ..4 to 2IX/ MHz I Kw pep. rating. DECCA-KW Balun MK 11. DECCA -KW E-ZEE MATCH The Decca -KW Balun is broadband.3 to 30 Antenna Tuner 10-80 metres. matches 50/25 ohm input to co-ex MHz, rated up to 2 KW pep. 1:1 Ratio 50 fed antenna's, also twin feeder and single wire systems. ohms 'unbalanced feed to 'balanced' output Waterproof moulded case. Suitable for Dipole Cramptons Road, Other KW Favountas—Decca KW Dummy Load. KW Trape and Beam Antenna. °Hord, loriginal and the bestl KW Trap Dipoles; Stockist for HY-Gain Kent TN14 5EA beams and Verticals: CDR % MOTS; Shure Microphones etc. Amateur Radio Products, Tel: Sevenoaks Write or phone for catalogue. DECCA COM MUNICATIONS LTD, 10732) 50911 SERVING RADIO AMATEURS WORLD- WIDE

MIC R O P R O C ES S O R RT T Y Are you looking for a system with a difference? NORDON DEVELOPMENTS are proud to introduce their Ti' 68A Microprocessor controlled machine. Easy to operate for the newcomer and the facilities incorporated should appeal to the RTTY Connoisseurs. The system is complete when used with your Rig, a domestic T.V. and a standard cassette tape recorder. The main unit is housed in a metal cabinet with handles. Blue texture finished. A rack system is fitted into the cabinet, which holds six plug in P.C. Boards. The Keyboard is a Heavy duty professional ASCII Unit housed in its own metal case. Textured finish Blue and Black. FRONT PANEL CONTROLS: Mains ON/OFF, Baud Rate Adjust. 175/425 Hz switch. Normal/Reverse switch and Reset Button also on the panel are edgewise TUNING METER and Keyboard Socket. REAR PANEL CONNECTIONS: Tape in out socket IDIN 5 Pin) Input from Receiver, Output to Transmitter. UHF Output to Domestic T.V. Channel 36. KEYBOARD CONTROLLED FUNCTIONS: * Cancel any function without affecting VDU (Screen of T.V.) * Write on VDU only * Send 'AY' continuously * Send 'Please KKK' continuously * Clear VDU Screen only * Type into a temporary memory one line of information, this can contain a CO call and this tine will be sent out and repeated after Car Return Line feed if Auto Call is selected * Send out to transmitter Information on the VDU FEATURES: * Transfer the information on the VDU to one of two memories * Adjustable Baud Rate * Send information on the VDU to a Tape Recorder * Automatic Sending of Letters/Figs and the unit will send as they are required * Receive Information from Tape Recorder and display on VDU * Bottom feed scrolling VDU 64 characters wide X16 lines with cursor. Black * Send from keyboard and display on the VDU characters on a white background. * Display on the VDU information as received * Temporary two-page memory store. The unit will automatically send Carriage Return and Line Feed at the end of any * Main control functions controlled from the Keyboard. line being sent. * Auto AY, Please K.K.K. Auto call and auto Carriage Return and line feed. Price TT6BA Main Unit £196 Including VAT * Complimentary high speed printer available soon. Price Ascll Keyboard £112 Including VAT Patent Applied for. * Professional Keyboard fully wired with 15 pin plug. * U.K. Manufacture with full after sales Service. Please write for further details to: — NORDON DEVELOPMENTS, Rear 10, School Lane, UPHOLLAND,

Skelmersdale, Lancs. Or phone Upholland (0695) 632225 Daytime Or RI Chorley 1025721 78347 Evenings. Callers welcome but please phone first. L. DEVELO P ME NTS

RADIO COM MUNICATION May 1979 479 C L O SE D CLOSED W E D N E S D A Y M ODULAR ELECTRONICS 8 AUG to 25 AU G A F TE R N O O N 95 HIGH STREET, SELSEY, Nr. CHICHESTER, SUSSEX. ANNU AL HOLIDAYS DISTRIBUTOR FOR THE PRODUCTS OF SOLID STATE SCIENTIFIC INC Telephone: Selsey (024 361) 2916 Type Specification Frequency Price TBA120 Int CCT IF amp/disc 66p + 12-5% FINISHED EQUIPMENT. VAT IS 12-5% on all. + VAT 8% MC7812 12V reg TO3 1 • 5A with our info for 6A 13-8V 2 METER RF AMPLIFIERS lin line) 13-8V supply. 2N4427 1W 10dB 12V 175MHz E0•84 PSU application E1.00 +8%. ME.FM 15-1 for 2200G min 13w out £35+ 2N3866 1W 10dB 28V 175MHz £0-78 Plas red t Bridge. 2-5A 400PIV 25p + 8%. ME.FM 15-2 for 2200GX min 13w out f:36+ 2N5913 2W 7dB 12V 470MHz CI -40 Diodes ZSZ76 1.5A 6COV 8p =8%. ME.202-25 for ICOM 202/215 25w out C37 + 2N3553 2.5W 9dB 12V 175MHz £3•96 2N5947 CATV amp Stud 1 • 2GHz 5W dise RF rep PA.1. 5uperpreamp 3N204 MOSFET E11•50 2N6080 4W 12dB 12V 175MHz (4-00 PT4I66c Man/Code only E1.00 +8%. 2 METER RF POWER MODULES (tested) 13.8V. 5D1143 10W 10dB 12V 220MHz E5-70 Dual VHF/UHF FET E420 IDual E300) In-house No. PM2- 10 10w for 0.4w 13.5d13 E15 -i- 2N6081 15W 6-3dB 12V 175MHz £5•50 Ideal for Mixers etc. With Data a .00. 8% VAT. PM2 15 15w for 1.3w 10.5dB (16 + 2N6082 25W 6-2dB 12V 175MHz E7•50 ANTENNA RELAYS. Mag. Dev. 951-170-12V PM2-25 25w for 3.3w 8. 5dEt (17 .5 + 2N6093 30W 5.7dB 12V 175MHz E8-40 70 Cm RF POWER MODULES (tested) 13-8V 50ohm good to 1296MHz. RG43 cable entry. 2N6084 40W 4.5dB 12V 175MHz 01-10 PM70-4 0-4w for 4w, 10dB 06.75+ £7.00 + 8%. RF2127 70W 6-6dB 12V 175MHz E23•50 PM70-10 2.5w for lOw 6dI3 C16.75 + HEATSINKS. Single sided. REDPOINT. VAT +8%. S01019-5 100W 6-0dB +28V 175MHz (18-70 PM70--10a 1 -6w for 10w 8dB E17•75. 6M1 2-6 deg C/W £1•30. 2N5590 10W 5.2dB 13.6V 175MHz (4-70 PA-U2 70cm Preamp. 12dB with Nf 2.(k1B E7.50+ 2N5591 25W 4-4dB 13-6V 175MHz £6•810 DAU 4-2 deg CAN ar .2, 60p. 55mrn square. Boxed BNC add (4.50 + VAT. 2N5944 2W 9dB 12V 470MHz £5•40 Post 259 on heatsink ONLY, due weight. FINISHED Prescaler Board. 50my at 432MHz. 2N5945 4W 8dB 12V 470MHz £7•60 COMPONENTS. VAT 12-5% unless marked. Max freq 503N1Hz +- 5V - Ve eanh 2N5946 10W 6dB 12V 470MHz 129-50 DAU PTFE 7mm Trim C 1.5-9pf or 2-18pf 18p. NEW In-line RF modules 144MHz with RF 501136 10W 5-5dB 12V 470N1Hz £6-40 Surplus 10mm Trim C 2-5-25 pf 9p. Changeover. 80 u 100mm. SAE for details. SD ice 25W 6-8dB 12V 470MHz (16-46 TETFER PTFE 1UHF.) 2-10pf only 25p, 2N5642 1W = 10W @ 13-8V: 2W = 13W @ 13.8V; SD1089 40W 4.3dB 12V 470N1Hz (19•50 CLYDON MICA 10-60pf good RF power 15p. 1W = 20W @ 28V. CCT data I:3-25 +8%. 2N5179 Gen. purpose amp. FT 900MHz CO-72 RS. Mica 4-40pf good RF power 20e. BFR16 113FR34 7072) 2.5d13 NF El •75 + 8%. 2N918 General purpose amp. £0.40 FERRITES. FX1115 1 hole 4p. MEID102 HC diode 90p +8%. ITT 0240C 10-7 xt1 Fill. 7.5kc 8/W 91011/2591 BFX89 UHF amp FT 1100MHz TO72 £0-90 FX1898 6 hole 10p. FX2049 2 hole 10p all 8% VAT. BFY90 UHF amp FT 10DOMHz TO72 (1.00 it6+8%. 402902 W out 144 near equiv BLY33 £1.00 PLUGS AND SOCKETS. IColinel alt 8% VAT. ITT 024B6 10.7 xt1 Fill. 15kc B/W 8200/10pf BNC 50ohm Plug 68p. BNC 1 hole Socket 56p. LOW NOISE DISCRETE SEMICONDUCTORS (8+8%. 4 hole 500 ohm BNC Socket 50p. TRW TP393 2dB @ 500MHz. T pack f2-00+ BLW16 1W/1-4W 175MHz 13.6v TO39 70p + 8%, Min. RF CHOKES 0.220h, 0•33ph, 20ph and 1000ph TRW TP491 1.6d8 @ 500MHz. T pack E3•10 + BFS28 75p. BB103 25p. TIL209 LED Bp. all 15p+ 12.5%. MUL 8FR90 3 - 2d13 @ 1 - 2GHz . T pack 123.25+ All +.8% MUL BFR91 2.5dB @ 1 -2GHz. T pack C3-90+ INTEGRATED CIRCUITS. VAT at 8%. HP5082-2800 I-1/C Diodes 79p. 2835 65p. SIG SD3C61 .5dB @ 144MHz. "D" MOS f2• 00 + Motorola MC12013-10 prescaler with UL output 5V HP5082-3080 Pin Diodes 70p all +8%. supply with data/input amp CCT. E10.60. SIG 502014-5dB @ 1-0GHz. "D" MOS C2-00+ MIN. INVOICED ORDER £10. NEW BF9OD MOSFET 2dB @ 200MHz C1.11+ Mc14951. C1.75. MOS 4001 18p. BFR34A 4dB @2GHz.T pack £1.70 + CAPACITORS. 12-5% VAT. 1000pf cfisc, 200pf Pottage: 359 up to C20 value. Above E20 add E1-00 3N204 2nd generation MOSFET C1.10+ disc, 33pf disc, all 4p. for post/insurance. 40673 MOSFET C0.75+ Feedthr Solder 1000pf. 500f. all Op. Minimum order C1.50 Min VAT free expon £16. ALL ABOVE ADD 8% FOR VAT UH F. Micadisc 33 and Upf all 12p. B/CARO or ACCESS over £10.

SEMICONDUCTOR OFFERS WOOD Et DOUGLAS 40673 C6p 2N4429 £2.00 2N5946 £10.00 BLW39 £.00 Following the huge success of our 70FM05 TA system we have 3N201 65p 2N4127 £1.50 2N5642 £3.50 CA3089E £1.10 great pleasure in announcing our latest kits for the amateur who TIS88A 40p 2N3375 £3.00 2N5643 £9.00 CA3023 79p can still use a soldering iron. 3N204 70p 21'45590 £4.60 2N5180 60p CA3018 60p 144F M2 TR 2M version of our popular FM transceiver giving MPF102 40p 2N5591 £6.50 2N2369 15p CA3031 70p 1-5 W on TX and 0-3uV on AX for 12 dB SINAD 40841 40p 2N6080 E4.00 2N3478 60p SL620C £1.50 BE 1 Extra board to reduce current consumption of 21,13866 70p 2146083 £8.50 BC183L 10p SLEGOC £1.213 2N3553 £1.00 2N6084 £1 1.00 BLY33 £1.80 MCI550G 70p both AX systems when handheld. 2144427 80p 2N5595 £15.00 BLY84 (4.00 MC1496 £1.50 M DO5T 384 M Hz drive source giving 0.5 W 2145913 £I.30 2146166 £18.00 BLY55 E3.00 CA3028B 70p FM/P M/ FSK /CW with modulator included. 741(81 20p 555 25p CD4020 60p CD4011 20p M D1OPA 384MHz amplifier to boost MD057 to 10 Watts. Plus all the firm favourites in use all over the country: 70F M05 TA 70cm FM transceiver Kit £45.50 inc 3W 2m 13V 6-CHANNEL TRANSMITTER FOR £35 70F M05 TR/A 70cm FM transciever Assembled £60.50 inc ASSEMBLED AND TESTED 70MC06 6 way multi channel set Kit £25.50 inc Board size 140 . 82mm • Frequency multiplication u 12 • Crystal sockets 70MC06/A 6 way multi channel set Assembled £38.00 inc HC25/U • Crystal pulling trimmers available • Minimum power 3W into 510)2 • RF bandwidth IMHz (145-146MHz1. 70F M10 0.5 W to 10W TX amp Assembled £32.00 inc Audio processor input impedance 30012 • Pre-emphasis, limiting, de-emphasis We can produce PCs from your artwork or your circuit diagrams and audio filtering circuitry • Sensitivity 2mV for 3kHz dev • Max dev EikHz • so for the next club project let us make a quotation for a profes- Circuit supplied. sional finish.

5mm coil formers with core 1200MHz) 15p LARGE SAE FOR THE LATEST LISTS AND ALL ENQUIRIES HC25/U crystal holders 20p 10.250MHz HC18iU crystals E2.00 1MHz HC6/U £3.00 9 HILLCREST, TADLEY, BASIN GSTOKE, HANTS RG26 6JB Hand held microphone with PTT switch and coil lead £8 Tel: TADLEY (07356)5324 lEyEtWkc1) S02313 socket 50p UHF angled plug £1.00 BNC socket 70p N Noe socket £1.00 G4EEE G8DC A G8M GC PAI resistors E12 100-1MS 5 of each value £3 10-7MHz crystal filters ITT 024DD £12.00 Relays 12v 2 and 4 CIO or 2 make 50p RS12 and RH12 relays £1.80 Balun transformer cores FX2249 and FX2634 5p GET THE MOST OUT OF YOUR HOBBY Suppression bead 1 core 2p 6 core 5p WITH A ROBOT '400' SSTV SCAN CONVERTOR I.C. sockets 8 pin, 14 pin, 16 pin 12p each VAT included Min order (200 PP 30p S.A.E. for details please, from the sole UK distributors AERO Et GENERAL SUPPLIES, NANAIMO HOUSE HELLER ELECTRONICS LTD 32 RUFFORD AVENUE, BRAMCOTE. NOTTINGHAM NG9 3JH 49 Blossom Waye. Hounslow. Middx TW5 9HB Telephone: (96021 397588

480 RADIO COMMUNICATION May 1979 William Munro (Invergordon) Limited distributors for NEC Amateur Radio Equipment

CG-P2200E 2M FM Portable 12 Channel Transceiver. Complete with Mic and Accessories. Switchable 1W/3W. Send for full Spec. 3 Channels £179 VAT incl. All Repeater Channels available and SO, S20, S21, S22, S23 ex stock at £3 per channel. Choose your channels from these and we will fit them. CO.-R700 6 Band General Coverage Receiver. 170kHz to 30MHz — AM, SSB, CW, RTTY. Built-in Mains Power Supply and Speaker with the new Auto-spread VFO. (Send for full Spec.) £220 VAT incl. CG 110E HF bands Digital Read-out Transceiver. CO 301 Matching Linear Amplifier. CCI 201 Matching VFO (Three oven controlled VFOs in one and acts as Digital Freq. Counter as well.) M 110 Matching Table Microphone. SP 110 Matching Speaker Unit/Digital Clock. (Full Spec. Prices and current availability on receipt of your enquiry.) NEC Equipment can be seen and handled at the following locations: Arncomm Services, 194A North°It Road, South Harrow, Middlesex, HA2 OEN. Tel 01-864 1166 Cambrian Communications. 2 Joseph Parry Close, Llandough, CF6 1PL. Tel 0222 702982 Peter Avill, 7 Moorland Crescent, Mapplewell, Barnsley. S. Yorks. Tel 0226 782517 Pace Electronics Ltd, 9 Lime Kiln, Wootton Bassett, Swindon, Wilts. Tel 0793 850356 Packer Communications, 28 Henniker Road, Debenham, Stowmarket, Suffolk IP14 6F'Y. Tel 072886 214 L. A. Wiles El. Son, Aisthorpe, Scampton, Lincolnshire. Tel 0522 71 351

Telephone 0349852.351 100 HIGH STREET, I NVERGORDON, ROSS-SHIRE V18 00N Telex 75265 ACCESS BARCLAYCARD HIRE PURCHASE

VF 2031 Hand-held 2M FM transceiver with nickel cadmium battery pack and HM 2140 HF Wattmeter with 120/240V AC SB 104A SSB Transceiver. Totally broad- •"''"" dual meters for forward and recharger. Optional banded, it eliminates the need for pre-tuning. lis4 reflected power. For use on 160 carrycase.external Operates USB LSB or CW from 12V auto to 10 metre amateur wavebands. microphone and electrical system. Hook up HP 1144 power n Operates on 9 volt battery. tone burst encoder. supply for fixed station use.

A small selection from the To Heath (Gloucester)Limited. Dept RC /5/ 79,Bristol Road.Gloucester.GL2 6E E Heathkit range of amateur radio equipment kits. Please send a copy of the Heathka catalogue. I enclose 20p in stamps IPlease send a copy of the Computer Brochure I enclose 20p in stamps. CI They all have excellent specification, top- quality components and an advanced design. With Heathkit you can build these first-class Name rigs for yourself.11e step-by-step instructions make it easy,and your success is guaranteed. Address Full details are available in the Heathkit catalogue. Send for your copy now. N.B. If you are already on the Heathkg mailing list you will automatically receive a copy of the latest Heathkit catalogue There are Hearhkil Electronics Centres at 233 Tottenham Court Road without having to use this coupon London 101.636 7349) and at Bristol Road, Gloucester 10452 29451) FREE Registered en England. No. 605177 vibro you receive your catalogue you will get details of this free offer.

RADIO COMMUNICATION May 1979 481 LOSING DX?

Can YOUR Antenna ANTEN NA FAULTY? Damaged? Traps off tune? Measure resonance and radiation resistance with an Antenna Noise Bridge, your receiver as null detector, 2-1000 ohms 1-30MHz do all this? (20.200 ohms 3)-150MHz), £3.80, get a STRONGER SIGNAL. V.L.F.? EXPLORE with a 10-150kHz Receiver, £10.70. A small selection from our huge file of testimonial letters on the JOYSTICK VARIABLE FREQUENCY ANTENNA (0.5-30.00N1Hz1. RARE DX UN DER QR M? DIG it OUT from tiring whistles and cw interference with a Tunable Audio Notch Filter, 350 5000Hz, G4DJY's COPY LOG shows 68 North Americans worked in the ARRL WIVE con- 40dB notch, speaker amplifier, £8.90, MORE DX. test. LINEAR OKAY? Two Tone Oscillator, switched single (for Morse WETYP worked WA6JPR over hundreds of miles on 40m, using the JOYSTICK practice, etc) or two tone, £8.70, stop wasting power. VFA and MICRO WATTS "equivalent to 1,000.000 MILES PER WATT- -A GOING L.F.? 1C0-600kHz Converter, built-in antenna tuner, WORLD RECORD -we can supply conclusive evidence! "I have used Rhombics, 4 rr waves in phase, centre fed dipoles, etc, but the 3.5-4MHz output, £9.90, EXTEND your COVERAGE. success I have had with the VFA has been AMAZING only 20ft high 'in front of SIG. GEN., 10Hz-200kHz, logic and variable sine or square wave my mobile home. I NEVER RECEIVE LESS THAN R7 AND MOSTLY R9 ON CWDX outputs, linear frequency scale, £10.80, a BARGAIN. WORKING-Bob Green, SUIKG/G3APH. W.B.E., W.A.C. Phone and CW. CLOB BERED? OR M ending your OSOs? Fight through VV70E, USA Government Electronics Engr. (retcf.1 claims "VFA 5ft below with a Speech Compressor, 1000:1 agc keeps your audio at ground, same as dipole, elevated 15f t, one "S" point UP on dipole." maximum, dynamic compression BOOSTS your PO WER, only £8.60. RADIO 4 GONE? 200kHz to Medium Wave Converter, built-in antenna, coax output, £9.70, ideal FRG7, etc. JOYSTICK ANTENNAS MISSING RARE DX? GET on THEIR FREQUENCY with a Crystal Calibrator, switched 1MHz, 100, 25kHz markers to 150MHz, no missing "even" ones, £13.80. SYSTEM "A" O RAfrW forpiheifilNL £41.00 TIME? MSF 60kHz Receiver, built-in antenna, 1000K m range, data output, £13.70. Sequential year, month, date, day, hours, minutes, seconds display parts (no case or pcb, Veroboard SY S T E M ' ' J,, (ImproPv.ede.P.: C1- on receive) £47.95 okay) for receiver £10.70, RIGHT TIME always.

Giro 21-923-4000. Please write for overseas prices. Each easy' assembled kit includes all parts, case, printed circuit, mating con- "PACKAGE DEALS" nectors, battery if used, instructions, postage etc, money back assurance so SEND off NO W. C O M PLETE RA DIO ST ATIO NS FO R ANY LO C ATIO N CAMBRIDGE KITS 45 (RSIti fi/tIod. taomoblLaneg e .

PACKAGE No 1 £272. 00 All packages include the Features R.300 Fla JOYSTICK VFA ¡System "Al 811 feeder, all PACKAGE No 2 £237.45 necessary cables, matching Features FRG7 Ru com munication head. phones. Delivery Securicor PACKAGE No 3 £212.45 our risk. ASSEMBLED IN GAREX (G3zvi) Features SRX 30 Fix SECONDS. You Save V.H.F. RECEIVERS New SR-9 for 2-metres FM, with 144- 146MHz f14.15 on each PACKAGE VFO. Improved 1speed slow•motion dial, also 11 xtal controlled chan- PACKAGE No 4 £402.00 DEAL! nels, ideal for fixed. !P or !M use. Built-in LS, 12v DC operation. WITH Our "Rolls" RX. FRG 7000 IMPROVED VFO STABILITY Er CAREFUL PRE.DELIVERY CHECK: EXCLUSIVE TO GAREX. f57.35 inc VAT lutais £2.50 each). Marine band version 1156 162MHzI £57.35 lutais £2.791. Sae for full details. Credit facilities available. RECEIVERS ONLY AMPLIFIED MOBILE EXTENSION SPEAKER the perfect answer for boosting audio level of IP rigs. 12V DV operation, compact built-in 6watt R.300 £184.50 FRG7 £199.95 amplifier, supplied with leads and jack•plugs 4 8S2 input. £11.25. Amplifiers, ex above, sold seo. at £2.70 each. SRX30 £174.95 FRG7000 £364.50 Integrated circuits: 723 1T05/, 75p: SN76660, 75p; CD4001AE, 25p; NE555, 55p; 709 IT051, 30p; 741 (OIL 8/ 30p; 7410. 25p. Neons Panel mounting, type JH8, brim hole, 240V, red, amber or clear. Just telephone your card nu mber- 3Sp each, any 5 + : 30p, 10 + : 27p. Miniature, wire end 89 each, 10+ : 6}p. 100+ : 4p. phone 0843 62535 (ext. 6) Resistor Kits. E12 series, 22.11 to 1M, 57 values. 5% carbon film, }W or BARCLAYCARD (or £039 after office 1W (please state). Replenishments available Starter pack, 5 ea value 12851 £2.95. Standard pack, 10 ea 1570) £5.40. hours) or write for details, Mixed pack, 5 ea 1,W+ 11/V (5701 £5.40. Giant pack, 25 ea 114251 £13.25. send 9p stamp airisk PL259 UHF Plugs +reducer 689 each, 5+: 60p. S0239 UHF Socket panel mtg 65p each, 5+ : 489. Note: All prices are those current at time of closing for press, NICAD RECHARGEABLES - physically equivalent to zinc-carbon inclusive of 123% VAT and carriage. types AAAIL116) f1.64; AAIU7) f1.20; C1U111 £3.15; DIL12) (4.94: PP3 £5.20. ANY 5+ : less 10%; ANY 10+ : less 20%. G3CED G3V FA Slide switches, min. DPDT 18p ea; 5+ : 14p. 10 • '12p. Toggle switches, min. full range SP thro' to 4P C/O sae list. GAREX FM detector and squelch conversion ready assembled with full fitting instructions. Tailor made, easy-fit design for AM Cambridge, replaces squelch board with minimum of other modifications, (5.40. PRTRIDglg- - Transistor Vanguard IAM25T1 version (modified squelch), £5.94. CRYSTALS FOR 10 METRES: IHC25U1 28,500MHz Tx plus 28,045Mhz fl P egROPOS I. PIPÇ hpu Liz-law for Rs (455kHz IF.) suit most "C.B." w/t £4.50 pair. AUTHORISED DISTRIBUTOR FOR REVCO AND LARSEN AERIALS; J.H. ASSOCIATES SWITCHES Er LAMPS.

PRICES ARE INCLUSIVE OF UK POST AND PACKING AND VAT

GAREX ELECTRONICS. 7 NORVIC ROAD. MARS WORTH, TRING. 6, Partridge House, Prospect Road, HERTS HP23 4LS MAIL ORDER ONLY Phone: 0296 668684 6.30pm-9pm & weekends only Broadstairs, CT10 1LD (Callers by appoint ment)

482 RADIO COMMUNICATION May 1979 MOSLEY WE ARE THE ANTENNA PEOPLE

Z°0°11-e,

Mustang Mk2 MONOBANDERS FOR DX For 10, 15 & 20 metres COMMAND YOUR BAND WITH A BIG PUNCH

SPRINGTIME IS ANTENNA TIME! We would like to offer you an extra 3db Gain! but all we can do is offer you a few dB reduction in price. MOSLEY ELECTRONICS LIMITED Administrative Address only 196 Norwich Road, New Costessey, Norwich NR5 OEX (All antennas available ex works, carriage and VAT extra) Send for HANDBOOK containing full range of Antennas and technical information, 28 pages 75p. S.A.E. for Price Lists

G3LLL ADDS BRIGHTNESS PLUS FREE RPT SHIFT TO G3LLL FT.101 NBFM UNITI I

Variable pre-emphasis to match your -.8114 voice and mic. Free RPT Shift till June 30th 1979. On demonstration FT.101. FT7. FRG7D00, FRG). FT223, SEM Europa, FDK700E and Multi U11. Super CW Filters for TS520 and 820, FT.101 and 301. J Beam etc stocked. Access. YAESU FREQUENCY STANDARD, MARKER Er CONVERTER Barclaycard, lull service facilities. SAE for EXTRAS CRYSTALS FT.101 accessories list. 5.0, 10.0, 10-7 Er 38•66667MHz 18U f2.70; 1-0MHz 6U or 33U HOLDINGS PHOTO AUDIO CENTRE £2.95; 100.0kHz 13U or 34U, 116.0MHz 18U £3.00; 455- OkHz 6U 39/41 MINCING LANE, BLACKBURN BB2 2AF. Tel: 102541 59535/6 £3.50: 200.0kHz 6U £3.70; 1.0MHz hi-stab 6U £4.25; 10.0MHz hi- stab 36U £6.00

HA M BAND AERIALS GALORE CRYSTAL FILTERS TELESCOPIC ALU MINIU M TUBING Smooth easy lining. Diameter sizes le - 1" - .3 - e I" - 3" - all sleeving in- Super selective 250Hz 8-pole CW filters for FT-101, FR-101, FT-301, to each other. TS-520 El 1S-820 £25.50 each, and (9MHz types with appropriate Suitable for Multi Element Vagi Beams. Tube cut to well designed sizes, carrier crystals): • 10 Metre Half Wave Elements 15 Metre Hell Wave Elements 9MHz SSB 6 pole, 13W 2.5kHz at -6dB and 5kHz at -60d8 £20.50 Dipole single element £.00 Dipole single element £7.00 9MHz SSB 8 pole, BW 2.4kHz at -6dB and 4.3kHz at -60dB 1124.00 Dipole and reflector £11.50 Dipole and reflector £13.50 9fV1Hz CVV 5 pole, BW 500Hz at -6dB and 2-2kHz at -60d8 Q2.50 Dipole Director and reflector £17.00 Dipole Director and reflector E20.00 9MHz FM 8 pole, BW 12kHz at -6dB and 21.6kHz at -03dB £24.00 Ada Ll.CV each element for Road (the despatch 10-7MHz FM 8 pole, BW 7.5kHz at - 3dB and 17.5kHz at -70dB 2 Metre Elements Tubing j' Butt edge tube. sections 42" long supplied with Boom clamp, bolt and end stops. 5 sections/elements 82.00. 50p for P&P. £24.00 All prices subject to VAT @ 123%. 10.7MHz FM 8 pole, BW 15kHz at -3dB and 35kHz at -70dB £24.00 UPPINGTON TELE-RADIO (BRISTOL) LTD 21-41V1Hz FM 8 pole, BW 15kHz at -3dB and 50kHz at -we D5.20 12/14 Pennywell Road, Bristol 8S5 OTJ. Tel: 0272 557732 455kHz CFU series ceramic filters, various bandwidths in stock £1.50 TBG-2 crystal tone-burst generator £8.00

G8M W W OFFERS Please add 12Si% VAT to all except frequency standard and marker 300 ohm RIBBON TWIN, 9p per M. post 139 per M. HC25U Crystal Sockets, crystals which carry 8%. Post free. 12p each, post 7p any qty. UR43. 50 ohm Standard Coax, 149 per M, post 231) per M. 30m Stranded PTFE Equipment Wire, 60p post 15p. UR96. 50 ohm Miniature Nylon Coax. 5p per M, post .3p per M. UR70. 75 ohm Coax, standard, INTERFACE QUARTZ DEVICES LTD 16p per M, post 23p per M. 8 core Screened Multicore Cable. 12p per M, post 29 Market Street, Crewkerne, Somerset, TA18 7JU 239 per M. Lots more on lists . . . SAE for copy. Tel: (0480) 74433 Telex: 46283 inface g. W H. WESTLAKE. CLA WTON. HOLS WORTHY, DEVON

RADIO COM MUNICATION May 1979 483 Rt lost. DIV fliFi which looks us if it isn't.

Thal's not to say it doesn't look like HP. • pet that it doom', look like the usu./ sort cl thine you ham come lo associate «ids DIY HIP. The Mk3 .tstrips and outperforms all tinternational British made H.F. tuners. and 111011 'mooned ones loo Cerlonly at Ihe pnce, these isn't ambi on near il. But more than Mat, d looks superb A small plc here would be on lensed PARTS FOR CURRE NT PW PROJECTS ... FROM AMBIT INTERN ATION AL so send an SAE lot deads on 16.511 that 100141 0.1 11111 It's something else VHF FM mood°, RX: A complete hot ol parls lo, Ihn protect, winch we firmly

believe will be an estabhshed - standarcr for years to come. The kit includes a Ill • Emmoresnely 6•11 orod anunc• exceenomells som e/forward ermoWlY 5 channel wretched crystal oselleof added to the board end. using diode switch- • 8ey•pure .tntl woo.. coma...on Forum *muff onumernomn m. rreenly ing. Uses cheap. 3rd OT crystal, employing onginal osellatot as x3 stage P m en. to twee rho 1.41.1/1 ro Ow tenstrom of nerAneel mionnorens Price depends on litter seeded lwe hare 011101.0$ types) end whelAm Or not chop • Venom *prone bed enOttlelo Are VP% ',Womble to ewe!. in outerno111 »pg. .

capaOtOrs a,. am/torte More notes on the Rol Irons our peen lab E25 (35 1..? to 11.• sytten, vMOS POWER TRANSISTORS FOR PW WINTON E9.95 pan • 2SK133/348 and now previe wing the MatClung 60 W/Channel V M OS ampli)ier FULL KITS FOR THE INV SANDBANKS MET AL LOCATOR W ould be ex dock) FULL KITS FOR THE FW DORCHESTER • attelong both Ow on/Seen, concepts of elm Mel,. elo Fr FM tome ()noel/ elenert more than me, • flowciu WAGS PITIMI ton clutocletliod no•vollv tot Itlf I sotercatotto TDAI062 HF/VHF tuna/wed 1 95 De mo appleo,e2.8.8 of pa .f« reo• • K 10 .1 .11APot ...o we by ma *Mo at or runner MOSFE Ts TOI 1013 One O A PAI1914 ra 1.95 peut 2901011.12.040 nI 0.80• • VU repo.% on the ammo nos sonsfey Amens to rol level 10/11090 On• lIr.9 tuF. mosOm 3.35 40822 FM pe at p Oa r • owh.d wlV lv. troul Are.° artttortno M hrneal doltuttto Atotot TOA12717 One due ern:len fs 1.75 40373 FM memo 0.51. 061197W 14191 »A run. IC 1.40 40673 Famous 410SfET 0_55. C6-31236 AM tuner IC 2334912re 133 170,100W MOSPOWCR T3A651 AA1 tuner 1C 1.1r:1 ovistol tbrotott 10 50. The PLII Dorrhester•LW,MW,SW.S. FIR stereo tuner CA30119E famous FM IF 1,1.1110 1.94 ISO Pro .00 . robs, CA3109( A. 3039. .101•1,00 mom Inns 5rnen 2 0.S unon T HE DIGIT AL D O RC HE STE R AL L B A N D TU NE R

Ai getAtotO. fle ,J5 0.0 014 0.14 cis, 1ty1.1•9 aloi mat 17711/ Orono . SoN 3000 2 20 Green 0.13 0.16 0.20 ID lél TI3A120 weft , emowleuefor 015 Ye * 0.115 0 15 0 20. wdh the rest 1.861205 raeh Wm 100 Own, 0 27 0 29 0,24 UI 04.125 MC1354» deed iF pump 1.20 --1 Al new 100 off to, tDtcottot All t toll MCI330. swots *590.4.. mueror 1.35 rarer of tuner 61 CIAM neon Masof 584406 [ mod. IF ononsp 0.65 f nenn mows.. 0.03 men O esitimis oxfoo equoprnent 04763 Irmung FM prawn° 1.85 o anapoonnao ÇOrnreol(nrCaloCen C /Culls Mlle 1(4 for rath0 ,4seIRO U23715 5 LED beepeoh Puree 0 110• Mhert the new range of OKI dog ma Imq .ncy display ICI was an.unced the ongsnal 529000 01.106 RF1116urer per 3.75 SA.56610 4 ststeon roue none IC 1.411. 1(136412 DO meet, IF• mt 7.55 prototype ot the Dorchester had been made • but since lo many of you wanted to we the SA.56710 *oh 4 shalom lo 6610 143 K.412 AlAiS58 dot «regim e 2-75 010 frequency counterdospley tynern wroth Me Dorchettr, we quickly designed a unit to MSM562314 Ler,61W,SW ene FM 0.0 .1 103141, we processor 2.56 ,1111 1toloty readout tallo incorporate the necessary laolities. The Dewed Dorchester rs dwiened in 19 Inch form, 6103357 hen trino 0 frIDFM yet 3.12 clod,. Om , ttopoldtch (14 • and forms a perfect match foi the othes w et in the tamp. II you don't want to go to 14810069 mew)er double MI mow 1.21 615615678 LIN/MW/FM OFM we. else erpenue ol the lull Ambit DE MI module. woth AMJF M/TirnefTimen, then the MA1023 Voltotera deco/fen • noose blanker P m. (04 LCD 011 • dock module can be used instead • 1.0013109 00011111 , LL emote, 2.20 11.0730 Cre mturne control 3.50 .0753 teottwea 1310 2.20 1CA740 OC tom con.ol 350 The Dorchmtei he been d.crebed In PIN D.. Jan and Feb m ues • but fos Mo w e CA3090.10 RCA Kt. Am mer 325 TDA1021 OC wood 11.1110 ISO VO* who may have smsted it .1 ss an All Band bioadcast tuner. covering LW/M W/S W on1196 reform . PLI. Moran M AI MS DC rime wroth 350 and FM std . es 6 swadsed ranges. Construction .s very straightforward, with all the wen lb.. P.M.O. 195 Paden and Tuner modules 0411223 10e IN telm canoe. low swdching being PCB «vaunted • and the ;evolutionary TOA 1090 IC used lot A M/F M. OttgOrnon, Oteit SIN 4.35 We cannot really fur •11 the

1(0 105 08 CY10 ele m. VAT on AI*. Item n remouelle 12R%. moms where rm. . 1• I c.f.i.,. ern iteo. sun 2SEp 41 ',elm.. Poe m. 2Streer pee. moo , en Ape 65 £3 Phone Orroneo M 102771 7180291227060 Ounlorn. Cedars ma mma me Shed.. • 2 Gresham Road, Brentwood, Essen.

REG. WARD & CO. LTD. G2BSG8CA W TONNA (F9FT) YAESU YP150• £58.50 FT901D £737.50 FC301 £108.00 NOW YOU HAVE A CHOICE! FT301D £585.00 FT225R £487.50 FP301 £98.00 CPU250ORK £308.00 Consider some of our features: FT101E £515.00 FT227RA r229.00 * Light weight * High gain F T2008., F P200 £420.00 FT227R '£213.00 FT7B £375.04) * Strong construction * Solid elements „ 7 F7202R £38.00 * Clean polar diagram £266.78 * Inconspicuous design FP12* £67.50 FL.2100B £311.00 FP4* £35.00 Compare these prices FL110 £130.00 YC601 £113.00 FR101DD £615.00 SP10113 £19.00 144MHz 432MHz FR101D £525.00 YD148 £18.50 4 El £13.90 19E1 £16.60 FR101S £395.00 YD844 £18.00 9 El fixed £16.20 19 El crossed £29.49 FRG7000 £327.00 YD846 £7.50 9 El portable £18.06 21 El £25.86 FRG7D £240.00 9 El crossed £28.13 21E1 ATV £25.86 FRG7 £187.00 SHURE 16 El fixed £31.05 144/432MHz Y0100' £145.00 444 £28.20 16 El portable £33.00Oscar special £29.29 YC500J• £168.50 201 £12.60 Telescopic portable masts 2511 £24.40 Telescopic portable masts 18ft £16.40 'Add 8% to these, others 12}% VAT

New 5052 Phasing Harness now available. These are high VALVES Most types kept. All valves for Yaesu in stock, quality units and come complete with "n" type connectors. valves for K.W. also. S.E.M. Equipment Most items held. K.W. Ancilliary Equipment Agents for: Agents for Ci2DYM Antennas ANDREW'S CABLE and SOTA COMMUNICATIONS EQUIPMENT J Beam 2m Antennas, Ascot Antennas Aerial Wire, Insulators, Co-ax Cable, Twin Feeder RANDA M ELECTRONICS WIGHTRAPS CO-AX SWITCHES 4 Severn Road, Chilton, Didcot, Oxon OX11 OPW HP available. Carriage extra Telephone: (0235) 834329/24844 Please check prices and availability before ordering ACCESS/BARCLAYCARD S.A.E. for pnce Itst, catalogue 30p post pad. Terms CVVO - Access accepted Carnage for antenna E2.00 Mainland only, Callers welcome, but by appoint GEORGE ST, AX MINSTER, DEVON EX73 5DP ment only please. TELEPHONE 33163

484 RADIO COM MUNICATION May 1979 G4D SG G3HEO D. P. HOBBS LTD. THE LARGEST STOCK THE CO MPONENT SPECIALISTS IN THE WEST

SEE YOU AT LONG LEAT JUNE 24 FDK MULTI 700E 1-25 watt 2mtr FM TCVR dig. readout L229.00 YAESU FT223 2mtr FM TCVR 3 channels fitted £155.94 YAESU FT202R 'Handie" portable, special limited offer £99.00 BOOTH HOLDINGS BATH YAESU FRG7 Receiver, 0-5-30MHz P.1.1 £210.38 SMC HF12Al2 2mtr Monitor RX. fitted 12 channels £78.69 We normally stock the following: LOWE SRX30 Receiver 0-5-30MHz PLI £75.00 PORTABLE 2 METRE SRS 2mu VFO Monitor Receiver £58.50 £159.00 CM170 144 PA10/40 Linear amp, £54 or £59 with RX preamp FM IC215, 3w, RO to R9, S20, 522 C1M70 COUGAR 2mtr -70cm FM Tranwertet, 2 only £45.00 FM FDK Palm II, SO-20-22, Ni-cads Er charger £149.00 CM9502 ROTATOR £50.62 SSB IC202S CW/USB/LSB £199.00 CM9523 ALIGN MENT BEARING £10,68 SSB MIZUHO SSB/C W £165.00 HANSEN DL20 10 watt Dummy Loads. 150MHz £6.90 Extra range £3.00 TOKO CFU050D 455kHz Ceramic Filters 409 ea. inc p&p 5kft. 3W Et 25kfl. 4W WW pots 30p ea. inc p&p MOBILE 2 METRE Tx/Rx 3300uF 63V 2.25A screw terns electrolytics 60p ea. inc p&p ICOM IC245E FM/SSB/C W multimode, Auto tone burst, two 3300pF 63V 10A screw term electrolytics 80p ea. inc pap New ITT 48V 25002 sealed relays DPCO 60p ea. inc p&p VFO's, Digital display with memory £399.00 ICOM IC280E Synthesized mobile rig you can split! Front section 3" deep £279.00 Also in stock - MICRO WAVE MODULES, CONVERTERS F: TRANSVERTERS, ,l-BEAM Et BANTEX AERIALS, RSGEI AND BERNARDS ICOM IC240 FM Synthesized Auto tone burst £198.00 BOOKS. FOK 800D FM 1 to 25W, Digital display. Freq. microphone SEND SAE FOR SURPLUS VALVE Et COMPONENT LIST controlled £289.00

Prices include VAT Access Et Barclaycard Remote digital readout for 800D Er 700E £19.95 FDK NEWIII MULTI 700E, FM, Pa, Digital readout, 1 to 11 KING STREET, LUTON, BEDS. Tel: 20907 25w, Synthesized, 25 or 12- 5kHz spacing f222.00 Open 9am-5.30pm Mon-Set. Closed all day Wed. ALSO VISIT- D. P. HOBBS (NOR WICH) LTD. BASE STATION 2 METRE HF BAND 13 St. Benedict's Street. Norwich, Norfolk. Tel 615786 ICOM IC211E FM/ USB/LSB/CW 2m Digital readout £559.00 Open Sam 5.30pm Mon- Sat. Closed all day Thurs. ICOM FABULOUS 701, 160 to 10m, CW/SSB/RTTY, etc, etc E766.00 ICOM 701 PSU -1C701PS £144. 00 SAMSON ETM - 3C KEYERS ICOM IC - RM3 Remote control for 701, 211E, 245E (95.00

Prolessional•grade C-MOS keyers built loi dependable Marine Et Commercial MOBILE 70cm use world-wide-Backed by Spacemark service. Only 1 µA battery idling current, ETM-3C. £63.88 FDK Multi Ull, 10 channels, RIT £Z99.00 ETM -4C ME M ORY KEYER -Has ETM-3C features plus 4 memories each taking approx 22 Morse characters (switchable 4 s 256 or 2 > 512 bits). MICRO WAVE MODULES TRANSVERTERS Et CONVERTERS Erase/rewrite as often as needed. Ely just pressing a button it sends COs etc.- MMT 432/144R 2m to 70cm with 1.6MHz rep. shift £169.88 once only, or repeatedly, and at any chosen speed. MMT 432/285 for satellites £133.88 JUNKER PRECISION HAND KEY. £36.54 Freq. counter M50/500 500MHz E69.00 BAUER SINGLE-PADDLE KEY UNIT. £11.66 88mH TOROI OS for my cw. sstv, filters, 90p each Plus other Microwave Modules products. SSB 90' AUDIO PHASE SHIFT NET WORKS, octal based PIP TONES Er PREAMPS (2m) AGAIN IN STOCK, £13.50. All prices postpaid and include 12.1,% VAT Please send slump mill ill enquiries SPACE MARK LTD. BARGAIN-CALLERS ONLY. Sealed lead-acid 6 volt 7V2AH THORNFIELD HOUSE. DELA MER ROAD. ALTRINCHA M, PRICE PER PAIR E12. Ideal for 12V 3A Tx/Rx. CHESHIRE (Tel 061-928 8458) Some 2m Tx/Rx's for HIRE, from £10 monthly.

Access Send SAE for All above include lists UK VAT WHAT ARE THE WILD WAVES SAYING? HP a pleasure! At li\ and delivery G2DY M ANTI-TVI TRAP DIPOLES All from S.W.L.-ing or Tiring at 250 watt PEP. £41.00 500watt Tx•ing or -Hi.0" for S.W.L.-ing £47.95 tall prices BOOTH HOLDINGS BATH 2 Kilowatt "THE BIG ONE- £56.25 include VAT 10-160 metres Aerial Matching Unit 500 watt and PFtP1 6 Golf Club Lane, Saltford, Bristol BS18 3AA Et S.W.L.-ing £18.25 2 K.W. model £24.50 Telephone Answering Service on Saltford 1022 171 2402 "MARBELL" MAYDAY S.O.S SUCCESS After 7pm for G3NXU (B. Booth) Full story, copy photographs, etc, as shown on BBC Nationwide, aerial article, Windsor (075 35) 51767 Bristol (0272) 712730 full details of the G2DYM "Mayday Cracker" anti•TVI aerial used: 10" > 8, 16p After 7pm for G8DPH After 7pm for G3X0D SAE and 3 x 9p stamps. A. Booth) (R. Horaman)

INCORPORATES HA M HIRE AN D RENT-A-RIG G2DYM, UPLO WMAN, TIVERTON, DEVON ME MBER OF TAFA

RADIO COM MUNICATION May 1979 485 CLASSIFIED ADVERTISEMENTS

Halle you gut it? Classified advertisements 2Ap per word, minimum £4.03. It may nut be Ile SUGGEST In Ile •sold. and o mat not be the LONGIST n Mr world, but Box Number £1.00 extra to wordage or minimum. certainly likely to le the mIni onfortmetne nIalrejare you will ter hi. >ea. If >our dune.. Include anything 10 du .ollh ndin rechnoloe>./ rom harrneurmal. I C;re.h..rr thud. Ilicetw , o.l. Semi-display 1/12 page (11" x 3"I (35 x 76mm) £23.00. AMIllra catalogue Wort tom in at he. been tee lome un an mo mpremItt world. and include, such 1/16 page (¡" x 3-1 (22 x 76mm) £16.00. tounlers from h.. wool.' of ...helm, a, 1001n IINIUSITI" complementary power tranotton. mlbet P or N channel I>pm (of Mr Please write clearly. No responsibility accepted for errors. hitherto meheardof mite of £9 95° pet paie in une oil qoantilim. Latest date for acceptance-6 weeks before 1st of issue month. klierometah'arnhlon dot' iron corm fo« «rumen, corr . and Allen lorordt from 0 I". tu 2 0' dia Plelà1 ImlIon... Whet IMO range, the Malaita, tptent and 'he In sirs SUN scrim. In DIY fonn All classified and semi-display advertisements must be prepaid. fro ,wireb orma ul np in JO *ay. per bracket. SUB mom are repIxementr Set . .. AR rte. new communicator. IC, fur /CI INI•5911 I,.,. 1010. Plere> end Molomla. ',nether with Copy and remittance to: C. C. LINDSAY, more Murata ...Mc Luker Moe, Wear ohm< Fkl IF fillen. imatal Cohen fro 10.`%111a. The incomparable URI 1_4 for digital Women, dim's.) rd tee med frrourro,..demsm for th,M1, 2 Leyburn Gardens, Croydon CRO 5NL. Tel: 01-686 5839.

Zn11:11'.511r1;e5% nre::r"iirrer::ti:;I ‘«rr.:11!;:r‘ren''t:4!..;', f,:27,:°'.1`d..: '1`17.7„briin, Members' Ads must be sent to the Editor at Chelmsford. rarer in the I.K. Ile Mark Truce FM mom sy.trm, 'al., 1/11 11111 oft Ihr .1.11ehrro tale' and smIting lo the temp mum rroi roily merlaorlar appeal:once and performance now - hwe Wier Mc 'nodular Mae FOR SALE iJi curn menun len, been *signed from the outset anth 0pdales' mind. we will be keeping Il use mrh the toms tor 11115 ahead. S.d aho addien power XIOSTET ampllf.n. ant/ SR montolled perampirftrn in marching aryln later thit inn. QSL & LISTENERS CARDS We offer quality cards, rapid turnaround So copy of Ile new AMIII1 .l,iUfoem part tom • aml pot ree >i.o haw one • 1. i5p opt It M./n «et 2, ri both Ph, il, NC eti,11$5. f“.0 IlOnlIlI • and very competitive prices. SAE for samples. G3VZF, 5 The Close, Mete from cu.... who Irme heed knot enough to r•arne their arprenalit. or Radlett, Hertfordshire. VALVES, new, boxed. EJM6, 6HF5, 6JS6/C, 6JB6/A, 6KD6, 6146B. Many other types. SAE for list. Wilson, G4AZM, Tel: Bolton 54165. JOHNS RADIO ALUMINIU M QUAD SPIDERS No boom or clamps required. £18 pair including p&p. SAE for details G3ZHC, Tel: Walsall (0922) 26659. QSL COLOUR CARDS printed to your specification on COLOUR RACAL EQUIPMENT ALL WITH FULL MANUALS. Receivers RA17 fully postcards depicting your area/home town from our extensive library. checked and tested. Rack mounting with dust covers, 5.0C-NewI12 louvred Kingsley Publications, 32 Chatham St, Leicester. metal case. E25.00 - RA98A New and boxed S.S.B. and I.S.B. convertor. f100.00- MA.1978 IA .T .U.1 Selector protector f.36,00 --Matching new 2M FM MONITOR RX MODULE, easy to build, no coil winding! 2 louvred case E15.00-RA17L Receivers, BOO in case-Tape readers type 65/5 ceramic filters. 6 channel. Dozens in use with GB3SR. Ideal SWL, and 6S16 new or used £5.00 to E15.00- Reperforator 7TR/3 new with spares Raynet, etc. 5 x 24 x sin. Details SAE. £24.30 complete kit. Built £29 £15.00 used 00.00- Redifon teleprinter terminal unit, type TT11 fully Iran. inc. Crystals extra £2.50 ea. G3WPO, 9 Alberta Walk, Worthing BN13 sistorised 600 ohms audio input. Power input 100 125 volts or 200- 250 volts 2SG. a.c. Contains internal power supply for teleprinter magnet coils. 0 to 100 bauds + unit made to operate Creed 75 teleprinter. Circuit included £25.00. tested. All COMPONENTS! 2N3055, 40p; S0239 sockets, 30p; hundreds of items ex-works. Cardage extra. S.a.e. all enquiries. Phone for appointment for others. SAE for full list. G3KTF (GTHR). demonstration of any item. TRIO TR3200 with 4 channels fitted. Hardly used. Excellent condition, original packing, £125. C. Farwell, 65 Brownfield Gardens, Maidenhead. JOHNS RADIO 424 Bradford Rd, Batley, Yorks. Tel: 38746. HEATHKIT "MOHICAN" Mt Mk II with manual. f25 cash. J. E. Tel: 0924 478159 (9.30 am to 1 pm) French, G3LGL. Tel Kinver 2461 (West Midlands). Buyer collects.

W ANTED

GOOD SECONDHAND EQUIP MENT ALWAYS WANTED. Come to 144i28MHz MOSFET Converter as PW October 1978 by G4CFY and best deal. 28/ I44MHz FETi MOSFET Converters, PC8 kit £8.50. Aligned and Amateur Radio Exchange for the 2 Northfield Road, Ealing, boxed units £17.00. PCB only £2.00, other parts available separately. London W13. Tel: 01-579 5311. 1750Hz Toneburst boards by G8IKP £3.50. P&P free. MISCELLANEOUS SPECTRU M CO M MUNICATIONS 12 Weatherbury Way, Dorchester, Dorset DT1 2EF PATENTS and TRADE MARKS-Booklet on request, King's Patent Agency Ltd (B. T. King, Reg Pat Agentl- 146A Queen Victoria Street, London EC4. Tel: 01-248 6161. Telex 8833805. Established 1886. IN D E X T O A D V E R TI S E R S

Aero Ft General Supplies 480 MK Products 478 T Es J ELECTRONIC COMPONENTS Modular Electronics...... _480 AJH Electronics Cover IV SPECIAL OFFERS Amateur Electronics 409/1 Mosley Electronics Ltd 483 TTL IC PACK: Unmarked, untested, mostly ttl (7400 series(. Ideal for learning Wren. Munro Onvergordon) Ltd... 481 Amateur Radio Exchange 474 about i.c.s. Pack of 50. 65p Nunsfield House Ambit International 484 Er 486 DIODE PACK: Unmarked, untested, mostly silicon types, some germanium Community Assn 477 Amcomm Services 397 Pack of 200 lapprox). 65p. Antenna Specialist (UK) Ud 477 Nordon Developments 479 WIRE PACK (11: Stranded connecting wire. Five colours each five metres. Partridge Electronics Ltd 482 Ashley Dukes 487 Total length 25 metres. 66p. BBC 487 PM Electronic Services 475 WIRE PACK 12): As above but solid conductor. 65p. PEA Electronics 486 J. Birkert 478 RESISTOR PACK: Five 11.,V z 10% resistors of each value in the E12 series Booth Holdings Bath 485 Quartz Lab Marketing Ltd 472 from 108 to 1M. Total of of 305. This pack is guaranteed. £3.25. Bredhurst Electronics 488 Radio Shack 466/7 All above prices include VAT and postage. Many other full spec. components Randam Electronics 484 Cambridge Kits 482 in stock. Send 10p in stamps for full list. Catronics Ltd Cover II SEM Electronics 476 Datong Electronics 473 Sheffield University 487 98 Burrow Road, Chigwell, Essex IG7 4HB Garex Electronics 482 Sota Communication Systems... 465 G2DYM Aerials 485 South Midlands Heath (Gloucester) Ltd 481 Communications Ltd 402/ 5 Heller Electronics 480 Spacemark Ltd 485 P Et R TEST D. P. Hobbs Ltd 4E6 Spectrum Communications.. The Tek Scope 545/A/8, 581,661 many others with plug-ins £99. Marconi Stephens-James'Ltd. 478 Holdings Ltd 483 SIG/GEN from £35. Deviation Meters £80. Advanced timer counters Integrated Circuits Unlimited 470 Thane Electronics 386/9 Interface Quartz Devices Ltd 483 Ta•J Electronic Components 486 from £30. Marconi Millivoltmeters from £20. Bridges from £30. Johns Radio 486 TMP Electronics Supplies 477 Transmitter receivers £100. Paper Tape Punches £25. Paper Tape KW Amateur Radio Products 479 University College 487 Readers from £18 to £125. Teletypes KSR 33 from £90 to £100. Lee Electronics 468 Uppington Tele -Radio Ltd 483 Teletypes AS R 33 from £180 to £210. Leeds Amateur Radio 469 Reg Ward Er Co Ltd 484 All equipment sold as seen. Open 9 till 5 inc Sat. Come and look Waters Et Stanton Electronics. -390/3 Leevers-Rich Equipment Ltd 487 round, no obligation. Around 2,000 items. London Communications 487 Western Electronics (UK) Ltd.. .386/9 Lowe Electronics 394/6 W. H. Westlake 483 Microwave Modules Ltd 471 Wood Et Douglas 480 Salcott Mill, Goldhanger Road, Heybridge, Minitenna Beams 477 Yaesu Musen Co Ltd 406 Near Maldon, Essex. Phone: 0621 57440.

186 RADIO COM MUNICATION May 1979 I-ILCIN E10111 GENERATORS ELECTRONIC AT KEENEST PRICES! 300-4000 WATTS AC, 6-24 VOLTS DC MAINTENANCE INCL. THE NEW E3500-115/230V AC & 12V DC CO OKERY BO OK SUPERVISOR MICRO W AVE £2.25 Incl. Postage LEADING MAKES OF MICRO WAVE OVENS FROM £199 inc. VAT ENGINEERING TRAINING DEPT, KEENEST PRICES INCLUDE UK DELIVERY EVESHAM, WORCS. Open Tues -Sat 10.30-1.30, 2.30-6.30 (Ansafone out of hours) FARNCOMBE ST, FARNCOMBE, Duties Directing a team of Broadcasting Engineers ASHLEY DUKES GODALMING (Tel 23279) SURREY responsible for maintaining the full range of professional radio and television broadcasting equipment. Irregular hours of working are involved. SITUATIONS VACANT Requirements Ability to motivate and lead other Engineers in such a way as to provide an efficient maintenance facility Recent experience.' of maintaining electronic equipment. A good technical UNIVERSITY OF SHEFFIELD knowledge of audio and/or video equipment. One of the following qualifications is essential:- RESEARCH TECHNICIAN (Grade 5) a) A degree front a British University in electronics or required for duties in the Space Physics Group within the Depart- Electrical Engineering. ment of Physics for an initial period of three years from the 1st April h) HNC or FIND (Electrical Engineering or Applied 1979. The successful applicant will be primarily concerned with the Physics). design, development, operation and maintenance of complex and cl C & G Full Technological Certificate in sophisticated apparatus, equipment and instruments used in Telecommunications. research into phenomena associated with the propagation of very d) A pass in the Council of Engineering Institution or low frequency radio waves. exemption therefrom Qualifications or experience should be of H.N.C. or equivalent standard. A current driving licence is essential and duties may include Reward A base in the Worcestershire countryside. some travel both within the U.K. and abroad for periods of up to Working in well equipped Radio and Colour Television several weeks. Studios. Excellent welfare and club facilities. Over Salary on scale C3186.0720 p.a. lunder review). five weeks leave. Generous pension and life insurance Please write to the Administrative Officer (Personnel). (Ref. schemes. S1214/ RC), The University, Sheffield S10 2TN. Further Details If you are interested please telephone Mr. D. G. Enoch on Evesham (0386) 41112, Extension 226. or write 01 head of Training Section (Technical Operations). Engineering Training Department. DEVELOP MENT Et TEST ENGINEERS Wood Norton, Evesham WRI14TE quoting reference number 79.E:4041/RC We have vacancies in our Development and Test Departments for Closing date for return of application forms 14 days Senior and Junior Engineers to work on professional audio tape after publication. recorders. A keen interest in audio and a good technical background are basic requirements. Test Engineers with management experience would be considered 000 for the position of Test Room Manager. If you feel you have something to offer and would like to join the leading British professional tape recorder manufacturer why not telephone or write to: Mr P. Lindsley, Leevers-Rich Equipment Limited. 319 Trinity Road, Wandsworth. London SW18 3SL. 01-874 9064. RADIO COM MUNICATION ENGINEERS REQUIRED Remuneration in the range of £4,400 and £4,900

UNIVERSITY COLLEGE LONDON Applicants are invited for the above positions at our North- West London and Harrow depots. We are London's largest ELECTRONIC TECHNICIAN Grade 4 required to assist in the con- independent radio-telephone company and would be instruction, modification and maintenance of electronic equipment for terested in hearing from you if your have knowledge of use in teaching and research carried out in Psychology Dept. of mobile VHF equipment. UCL. The work is varied and interesting, and covers a wide range of Contact Mike Rawlings or Bill Clarke on 01-328 5344. analogue and digital techniques. ONC. CEtG or equivalent required. Salary (under review) in range E3,420-E3,867, inclusive of Lon- London don Weighting. Application Form from Personnel Officer Communications (Technical Staff CK2I University College London, Gower St, (Equipment) Ltd London WC1E 6BT. 30 Boundary Road, London NW8 01-328 5344

RADIO COM MUNICATION May 1979 487 foR ero wee I bl 11AVO COMMUNLCATIONS tr hut-7 e electronics

22 REGAL HOUSE • PENHILL ROAD • LANCING • WEST SUSSEX Telephone • Lancing (09063) 63119 (mg)* 2 .4 /tour al-ewe-Me seele/e) OPEN 9-5 MONDAY -SATURDAY

FDK SHURE MICRO WAVE MODULES Multi 700E 2M FM synthesised £229.00 201 Hand mic £11.25 (10.50) MMC 704M cony £20.25 Multi 800D 2M FM with memory £289.00 444 Desk mic £32.00 100.501 MMC 144/28LO 2M cony with local DD800 Remote display for above £19.95 5561 Desk mic with preamp £9.60100.501 ose olP £22.W Multi U11 70cm FM with 10 channels £299.00 MMC 144/ 2M cony any IF £20.25 Multi 2700 All mode 2m with OSCAR £499.09 NAIGAI MMC 432/26 70cm cone £29.90 Palm 22M FM Hand held with nicads £139.00 MMC 4321144 70cm cony 144 out NAG 144XL 2M Linear 500W PEP in £481.00 £29.90 TM568 2M Scanning monitor RX £105.00 MMC 1296/28 23cm cony £31.40 MINI PRODUCTS MMT 432/213 70cm transverter to 10M £133.00 ICOM MMT 432/144R 70cm transverter to 2M £170.00 H01 Minibeam 10/15120M £98.50 (£3.00) C215E Hand held 2M FM £159.00 MMT 144/28 2M transvener to 10M £89.03 C4 Vertical 10/ 15120M no radials £44.50 (£3.001 C240 Mobile synthesised FM £189.00 MMA 144 2M pre amp £14.63 C280E Mobile 2M uP controlled £245.03 MML 4321100 100W 70cm Linear £247.00 C245E Mobile fixed 2M all mode £399.00 SAGANT MML 14.41100 100W 2M linear £139.50 C202E Hand held 2M SSE £199.00 EL4OX De luxe 80/20M dipole £29.95 (£1.001 MMD 0501500 500MHz counter £69.00 MMC 28/144 10M to 2M cons C21 1E Fixed 2M all mode £559.00 £20.25 MMA 28 10M pre amp C402 Hand held 70cm SSS £259.00 HYGAIN £15.00 C701 HF all mode inc peu £999.00 12AVO 10/15/20M vertical £42.18 (02.00) WATERS Et STANTON 14AVO 10115/20/40M vertical £59.06 (£2.001 HP3A TV1 High pass filter 12.95 100.20) YAESU MUSEN 18AVT 10/15/20140180M vertical tes.so (c2.501 FT227R Synthesised 2M FM £239.00 WESTERN ELECTRONICS FT202R Hand held 2M FM £99.00 SOTA PM2000 PEP reading wattmeter £50.63 (£1.001 FT7B H F mobile SSS 100w out £421.00 EDT 144,28 2M Transvener £112.50 ASW1 3.way coax switch £10.12 (00.751 FT7 HF mobile SSE1 10w out £299.00 EDL 144S 2M Linear 100W out £144.00 DX5V..AII.band HF vertical ant £59.00 (£1.001 FP4 12v DC PSU £39.50 EDI. 432P 70cm 50W Linear £152.00 FT2COB HF fixed station £395.00 SWR Bridge VHF £37.80 (CO 751 ROTATORS FT301 HF fixed all solid state £579.00 AR30 Light VHF beams £46.13 (12.001 FT901DM The ultimate HF transceiver £960.00 JAYBEA M AR40 Large VHF beams £53.54 (£2.001 FRG7 HF general coverage RX £210.00 CD44 Medium HF beams £106.87 (£2.001 FRG7C00 HF gen coy digital readout RX £364.00 C5/2M 5dB glass fibre collinear £35.00 (£2.00) HAM 11 Large HF beams £145.13 (12.00) FT101Z0 HF all mode transceiver £647.00 5Y/2M 5 ele yogi £8.66 (01.03) 9502 Colorotor VHF 3-wire control £50.82 112.001 FT101Z HF transceiver Ése.so 8Y/2M 8 ele vagi £12.50 1E1.003 KR400 Medium HF 3-wire control £95.63 (£2.00/ 10Y 2M 10 ele vagi £24.18 111.501 PBM14/2M 14 ele parabeam (36.55 (£2.00) ADONIS 5%Y/2M 5 ele crossed vagi £18.00 (01.513) DENTRON MMO2G Mobile mic with pre amp £19.95 1E0.751 8XY/2M 8 ele crossed yagi £22.50 (12.00) MLA2500HF 2kw linear £695.00 AM502 Desk mic with compressor £39.95 (£0.75) IOXY/2M 10 ele crossed vagi £29.81 (E2.03) MT3000A 2kw HF ATU £275.00 AM802 Deluxe desk mic with compressor 0412M 4 ele cubical quad £18.68 (01.50) MT2000A 2kw HF ATU £175.00 £59.95 100.751 C1612M 6 ele cubical quad £24.75 1E2.003 160AT 1kw HF ATU £99.50 UGP/2M Ground plane £7.98 (C1.001 JR Monitor 300W HF ATU £59.95 MM/2M Halo with 2ft mast £4.39 110.751 ANTENNA SPECIALISTS W2 Direct reading 2kw wattmeter £69.00 C8/70cm 8dB glass fibre collinear £44.43 (12.00) ASP201 2M } A £2.95 (£0.75/ GLA1000 lkW HF linear £289.00 MBM48/70cm 48 ele vagi £24.53 (£2.00) ASP2009 Economy 2M 1 A E7.95 (10.76) M8M88/ 70cm 88 ele yagi £32.62 1E2.00/ ASP677 2M 3dB IA £14.95 (10.751 MIZUHO 8XY/70cm 8 ele crossed vagi £27.11 (12.00) ASPE667 70cm 6dB collinear £19.02 110.751 582M Hand held 2M SSB £165.00 W21 21in stand-off wall bracket £11.48 1£2.03/ ASPE452 70cm 3dB collinear £7.50 110751 Nicads £10.00 DL Double chimney lashing kit £9.23 (11.00/ Magnetic mounts for all above £8.50 110.751

All items normally in stock Carriage free except where shown in brackets All prices include VAT Send SAE for literature on any of the above

Sa me day mail order despatch - or just phone your credit card nu mber

Extensive stocks of Secondha nd equip m ent - please ph one yo ur require ments

• W e can let you co m pare the equip ment side by side in our sho wroo m •

• W e aim to provide an unbiased personal yet professional service •

A C CE S S - B A R C L A Y C A R D - INST A N T H.P. - P A R T EX C H A N G E

488 RADIO COMMUNICATION May 1979 PUBLICATIONS OBTAINABLE FRO M RSGB RSGB me mbers can obtain a 10 per cent discount on the prices listed be/ow at the time of ordering (excluding Ham Radio Magazine and Ham Radio Horizons). To obtain the discount, deduct 10 oer cent, calculated to the nearest oennyirom the total value of the order (using the latest price list) end enclose a remittance for the balance. Also enclose a recent Radio Communication address label as proof of membership.

RSGB PUBLICATIONS OTHER PUBLICATIONS Technical books American Radio Relay League A Guide to Amateur Radio 117th edn £1.71 Antenna Book (13th edn) . . . £3.86 Amateur Radio Techniques (6th edn) £3.95 Course in Radio Fundamentals . . . £2.96 Morse Code for Radio Amateurs 54p Electronic Data Book. . . . . £320 OSCAR-Amateur Radio Satellites . £4.20 FM and Repeaters for the Radio Amateur . £3.09 RSGB Amateur Radio Call Book 1979 £3.21 Getting to know Oscar from the ground up. £2.46 Ham Radio Operating Guide £3.19 Radio Amateurs Exammatinn Manual (8th edn) £2.16 RAE Questions and Answers . . . £2.00 Hints and Kinks £3.08 Radio Amateurs' Handbook 1979 (Paperback) £7.36 Radio Communication Handbook (5th edn) Vol 1 £9.36 Radio Communication Handbook (5th edn) Vol 2 £8.12 Radio Amateurs' Handbook 1979 (Hardback) £1021 Radio Data Reference Book (4th edn) . . £3.65 Radio Frequency Interference . . . £2.90 Teleprinter Handbook . . . . . £8.89 Single Sideband for the Radio Amateur . £3.52 Test Equipment for the Radio Amateur (2nd edn) £4.42 Solid-state Basics . . . . . £4.51 TV) Manual (2nd edn) £1.56 Solid-state Design for the Radio Amateur £5.80 VHF/UHF Manual . . . . £6.82 Specialized Communication Techniques . £3.19 World at their Fingertips (Paperback) £1.63 Understanding Amateur Radio £3.65 World at their Fingertips (De-luxe) . £2.76 VHF Manual £3.74 Radio Amateur Callbook Inc Log books American Callbook (USA listings) 1978 . . £9.75 Amateur Radio Logbook . . . . . £1.63 American Callbook (DX listings) 1979 . . £10.28 Mobile Logbook ...... £1.00 World Atlas (Amateur radio prefixes) . . £1.75 Receiving Station Logbook £1.54 Radio Publications Inc Beam Antenna Handbook . . £3.90 Maps, charts and lists Better Short Wave Reception (3rd edn) £3.42 Countries List/HF Awards List . . . 25p Cubical Quad Antennas £2.77 Great Circle DX map (in tube) . . £1.29 Simple, Low-cost Wire Antennas £2.89 Oscar map (in tube) ...... 43p IARU 0TH Locator map of Europe (wall map) . £1.15 Miscellaneous QTH Locator mao (Western Europe) (on card) 57p Amateur 1 elevision . . . . £2.20 UK Beacon List ...... 19p Care and Feeding of Power Grid Tubes £2.82 UK Repeater List . . . 19p Complete Handbook of Slow-scan TV £5.58 IARU Region 1 Beacon List . 19p Radio Valve Er Semiconauctor Data . £400 80-metre DXing £2.86 Me mbers' sundries RSGB pennant f2.35 RSGB station callsign plaque' . £5.50 RSGB de-fuse lapel badge' £2.85 M ORSE INSTRUCTION AIDS Callsign lapel badge' . . . £1.95 G3HSC Rhythm Method of Morse Tuition- Lapel badge (RSGB or RAEN emblem, pin fitting) . 51p Complete Course (two 3-speed 1p records and one Tie (Maroon or Blue) . . . . £1.96 ep record plus books) ...... £5.601 Radio Communication Easibinder . . . . £3.00 Beginner's Course (one 3-speed 1p record and one Car window sticker (RAEN or RSGB) (seit-adhesive) 31p ep record plus book) ...... £4 . 121 Members' headed notepaper (50 sheets) quarto 85p Beginner's 1p (0-15 wpm) plus book £3 44t Members' headed notepaper (50 sheets) octavo . 60p Advanced 1p (9-42 wpm) plus book £3 441 Radio Communication back issues (As available) . 84p Three-speed similated PO test 7in ds ep record £1.151 RSGB contest log sheets (100) . . 77p 1 Overseas oroers: add £1.12 RSGB teeshirt (large, medium or small) . . £2.25 ' Delivery approximately live weeks M AGAZINE SUBSCRIPTIONS Prices include postage, packing and VAT where applicable_ For air OST (including AR RL membership) (per annum) . . £11.84 mail despatch, please ask for price before ordering. Goods are Subscriptions for OST should be sent to RSGB, 35 Doughty Street, obtainable, less p & p. at RSGB headquarters between 9.30am and London WC1N 2AE. 5pm. Monday to Friday. Ham Radio Magazine (per annum) (incl air POSTAL TER MS: Cash with order. Stamps and book tokenb delivery) ...... £14.00 cannot be accepted. Cheques and postal orders should be crossed Ham Radio Horizons £6.00 and made payable to -Radio Society of Great Britain". Giro A/C No Subscriptions and changes of address for Ham Radio 533 5256. Magazine and Ham Radio Horizons should be sent to: Ham Please write your name and address clearly on the order. Radio Magazine (UK), PO Box 63, Harrow, Middlesex HA3 6HS. ORDER FRO M:

RSGB Publications (Sales), 35 Doughty Street, London WC1N 2AE A. J. H. ELECTRONICS (G8AQN) Proprietor: A. J. HIBBER D Tel RUGBY daytime 76473. evening 71066 Terms of Business: Cash with order. Mail order only, or Callers by appointment. S A E. with enquiries Handling Charge 40p Minimum order £1.00. Official orders accepted on a strict monthly basis. Prices no w include VAT FULL MO NEY-B ACK GU ARAN TEE ON ALL ITE MS

"KENT MODULES" STEREO CAR CASSETTE PLAYERS famous manu- HP5032-3080 VHF/UHF pin diode 50p or 4 for "FT 101 NBFM ADAPTOR" By the time you read this facturers warranty returns fully overhauled and in £1.50 advertisement we should have this unit available; working order 5 watts per channel output. con- PETS Er MOSFETS this vein give you Tx & Ax NBFM with your FT101 trols = volume, balance, tone, fast forward and re- 2N3819 "N" chan. ft 20p With only one simple internal connection. SAE for wind, auto stop. Supplied less speakers and power 2N4381 "P" chan. fet 20p full details and price. lead but we do supply power plug and circuit. LIST TIS88A "N" chan. fat 389 CONVERTOR for 145MHz requires osc. 10-7MHz PRICE over £50.00 OUR PRICE ONLY £20.00. 314204 mosfet with max. 2-5db NF @ 200MHz output £12.00. 10.7 MHz RADIOTELEPH ONE M ARKER 24db gain (RCAI £1.10 6 CHANNEL OSCILLATOR for above convertor re- OSCILLATOR UNIT built into small die cast box TRANSISTORS quires 44MHz type crystals £12.00 with internal battery brand new supply ex-stock BF115, 15p, BF152 12p. 6E166 18p. BF180 22p. 10.7MHz NBFM IF AMPLIFIER with crystal filter for £14.04 post oaid lother frequencies made to coded. BF194A 10p. BF195 10p, BEY50 20p, BFY90 90p. 7.5KHz channel spacing £26.50 UR55/U CO-AX DOUBLE SCREENED 50 ohm 209 BC108 iCIL108) plastic, 10p. BC172, BC172A, 2 vvArr AUDIO Ft SQUELCH UNIT to match above Mu., minimum supplied 5 Mtrs. BC172C 12p. MPS918 (plastic 21491811 89. ZTX107 IF unit ISM. PTE WEST MINSTER SINGLE CHANNEL 15p ZTX310 15p BSX20 20p. ST2110 aim, to 2N918 The above four boards make a superb 2 meter OSCILLATOR BOARDS for W15AM 79-101MHz FT950 MHz good VHF Tx driver 100 m/w 10p. receiver with a sensitivity of better than •25uV for Tx. coil can be rewound to suit any frequency re. RF POWER TRANSISTORS 20dB quieting. SPECIAL OFFER the above four quired for Is or Ax. New @ only 80p each. 5 for 2N5070 30MHz SSS linear 25 watt pep output 28v units for £55.00. 0.00, 10 for £5.00. stud mount with 13db gain requires only 1-25 watt LOW PROFILE RELAY 2pco. 12V coil OK for 2 mtr AE STEREO CAR CASSETTE player amplifier boards with drive, supplied with data sheet showing 30N1Hz 25 relay up to approx 10 watts PC mounting £1.75 two amp. ICs NEC.uPC 1001 H2, requires 12V D.C. watt PA unit manufacturers price alveoli £20.00 CAR CASSETTE/RADIO STEREO AMPS 5 watts 33W per channel, removed from new equipment by our price while they last ONLY £.00 output per channel. Complete with multi gang pot manufacturer, size 120mm u 45mm, supplied with kern 27MHz driver 75m/w in 400 m/w out 112v) for volume, balance, tone, Et on/off, amp consists circuit, £2.25 each. TOS case 75p each of two 5.8 watt ICs (TA7205PI Rs Et Cs on PCB FM RADIO FRONT END TUNER Units 83-108MHz 2N2631 VHF driver 1 watt M @ 50MHz gives 7.5 25mm x 100mm we supply data on the ICs Er cir- (remove three Cs and it tunes Air Bandl and 2m watts with 29v supply £1.03 cuit of complete amp. EX-NEW equipment E- very high quality and stable unit with exceptional 2N5947 marked SRF1117 FT 1•50Hz 3 watt out @ tested before despatch ONLY £2.00 sensitivity FET RF amp. NPN mixer and separate 430MHz @ 12v 689 AMPHENOL CO-AX RELAY 26v DC. fitted 50 ohm osc. AFC and AGC inputs, works from 9-15V D.C. FERRITE CORES mixed bag 100 50p "N" sockets and power rating 1 Kw CW @ with circuit; new and unused BARGAIN @ £4.00 AUDIO AMPLIFIER ICs LM380 2 watt @ 12 volt into 4 5COMHz 500 Watts @ 3 GHz VSWR @ 1GHz each. ohm 85p 1-12-1. These are new and unused and offered at a TBA641A 2-4 watts into 4 ohms @ 9 volt data VARICAP FM TUNERS 88-108 MHz, small size 70 x fraction of cost. ONLY £35.00. £1.25 55 x 30mrr. 10-7 MHz IF, 2 dual gate MOSFETS + PYE EUROPA HIGH POWER TRANSMITTER TA72C6P 5•13 watts into 4 ohms @ 13.2 volt ex' two transistors made by "Rank". Sorry no data. BOARDS minimum 25 watts RF output and will new equipment with data sheet 90p £3.50 each. tune 145 MHz; this has three channels and more ESM231 18 watts into 4 ohms @ 24 volt with data CRYSTALS OK for 2 Mtrs ie: x4 + 10.7MHz, 33•5, new only £1.80 can be added if required. This board also contains 33• 550, 33•600. 33-675, 33•700, 33725, 33750, the mic amp. and aerial filter, offered new unused TAD110 IF amp for AM/FM receivers no data £1.50 33- 775, 33•800, all £1.25 each. HC6U types. untested @ £30.00. CA3029E IF amp for FM receivers NBFM or WBFM SECOND CONVERSION CRYSTALS 11.170 HC6/U, £2.00 with data sheet TRIM MER CAPACITORS 11.155 HC6/U, 10-230 HC6/U Er HC113/U, all NE565 timer 359 lOmm dia. ceramic 2-8pf. 3-10pf, 4-20p1, 10-40p1. £1.75 each, 4,000MHz HC6/U r2.00. 741 op amp 27p all 10p each. FREQUENCY STD. CRYSTALS 1 MHz HC6/U, lOmm dia, film sermairspaced 2-25p1 8p or 10 for DISC CERA MIC CAPACITORS 5 MHz, and 10 MHz HC113/U; all £.00 each. 50p. 4-60pf 10p 10 for 75p 1003pf. 2200pf, 500vvv, 0.1mf 3vw, all 10 for 150 512 BIT SHIFT REGISTER IC's type MM5016H. 7mm dia, film semi•airspaced 1-10pf, 1-16pf 0•047m1 30inv 10 for 20p. 100pf co-axial discs Normal price over £.03, our price only 60p; two 1.4-5.5p1 all 10p 500vw very small PKt 20 for 20p. for £1.00. 7mm sq film semi-airspaced 1-3.5ot 2-100, 279f. 5000pf 500vw both types 12mm dia. 10 for 10.7 MHz CRYSTAL FILTER 0240E 12; kHz channel 2-18pf all 10p 159 spacing, 33 kHz imp. 820 ohm. £7.00 each. 10-60pf as used in PYE Westminster PAs 15p 0.01 mf 2. 5kv Sp each, 1030pf 1.2kv Sp each. CERA MIC COMPRESSION TRIM MERS CO-AX PLUGS/SOCKETS: 50 ohm "N" socket CERA MIC FEEDTHROUGH CAPs. 1CO3pf 500v. 70p. "N" plus for UR76 etc. 65p, free "N" 200- 1200pf size 15 x22rnm PC mount 20p solder in type requires 3mm hole 10 for 20p socket right angle cable mounting for UR67 75p. 75 10-40pf size 8x 13mm PC mount 89 SLIDE SWITCHES 2.p.c.o. 10p (pre-set type 10p 10 10-80pf size 9 ti 14mm PC mount 89 or 10 for 609 ohm "N" plug for RG164 75p. 50 ohm BNC right for 50p angle adaptors 50p, SPECIAL OFFER 75 ohm BNC TETFER TRIM MER 1-10pf 9rnm sq tab ends 25p, PYE COILS 5mm dia. 10m sq. base P.C. mounting with plugs b single hole fixing sockets ONLY 359 each. 1-10p1 9mm dia. PC mount 25p core 10 for 60p, as above but 4mm dia. 6mm sq. S0239 UHF sockets 4 hole fixing 50p. Screening PFTE wire ended tubular trimmer 0.5-6pf 5mm dia base 10 for 60p shields for S0239 sockets 20p. 50 ohm BNC plugs 15mm long 10p NEOSID COIL FORMERS horizontal P.C. mounting for min. coax 60p. P1259 plug for UR67 %p. JACKSON butterfly trimmers 10+ 'Opt 50p. with tags each end 4-5mm dia. 15mm long with 17 + 17pf 60p P1259 plug for UR43 65p. 5011 "N" socket 609. core new unused 6p each 10 for 50p AIRSPACED CERA MIC TRIM MERS 1-15pf lOmm IRON CORED HASH FILTER CHOKE suitable for SWITCHES (rotary/ sq 20p, 2-30p1 Ilmm sq 20p mobile Ax etc. rating approx 2A. size approx 25mm 3p 3 way with earthing ring + off position 1" dia. BY REQUEST NEW SUPPLY OF COMPONENTS cube chassis mounting 20p. std 3" shaft. 40p FOR FREQUENCY COUNTER as March 76 R.C. PHILIPS SYNCHRONISATION UNIT LOH4310 for 3v 1 pole 12 way break before make r dia. std SN7490 609 MINI COMPACT CAMERA used to synchronise shah. £1.00 NE529K £1.643 SN7473 two cameras to one monitor new in original boxes 2v 1 pole 12 way break before make 1" dia. std 3" MC10116 70p SN7475 46p £7.00, copy of handbook £1.50. shaft. 80p MC10131 £2.00 SN74121 30p SEMICONDUCTORS PUSH SWITCHES SN7400 17p SN74141 75p ZENER DIODES 400m/w 3.3v, 3.9, 4.7, 5•1, 6-3, 3 banks of 4 pole change over self cancelling for SN7413 25p SN74196 £1.05 6-8, 7.5, 8-2, 9-1, 10, 11, 12, 13, IS, 18 Er 24v all PCB or panel mounting 75p MINIATURE NIXIE TUBE ITT 58635 5 for £2.50. 10 12p each, 2 pole change over for PCB or panel mounting 25p or 10 for £1.75 for £4.50 VARICAP DIODES ITT210 lOpf @ 4v for VHF/UHF 4 pole change over for PCB or panel mounting 309 10,000 MFD 16i.rw 40p tuners to 1GHz 1513 10 MFD 354vw 15p ITTBA111 55pf @ 2v 12p or 10 for £2.00 TOGGLE SWITCH 2 pole change over with centre off. BRIDGE RECTIFIER two required 5Dri each. BEI105 2pf @ 25v for VHF/UHF tuners etc. match- 1144005 rectifier diode 10p. ed sets of 4 80p 250v @ 10e. 34 x 17 x 25mm 469 5v 1 amp regulator MC7085 TO3 case £1.60. SIGNAL SWITCHING Er RECTIFIER DIODES CRYSTAL HOLD.f RS HC25/U 13p. HC6/U 13p. 6.2v zener 12p. 1N4148 3p 10 for 209. FT243 13p. 1000pf 500v feedthrough caps, 3p each 10 for 20p. XD201 (0A79) Sp STOCK LIST NOW AVAILABLE 15p sumps 2N706 transistor 209 each. 1N54A 5p pisase.

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