Radio Nication Odio S • Ot Brit

September 1977 radio nication odio S • ot Brit

N F D 1977

Results in this issue

Thames Valley ARTS operated with all the home comforts of a member's caravan at Kempton Park Racecourse; G3GTX on the key, with G30GP

Verulam ARC's HF NFO station was visited by an "official" RSGB inspec- Keenness and determination on the face of tor (G4BOU) complete with standard Tom my Boucher, Inr op of G3OLB. at the Bristol bearer (G3JKB). They carried out a Contest Group's HF NFD station. Photo: G3TKF most thorough inspection of a great many things that did not really con- cern them and made use of an unbelievable amount of test gear they brought with them! Needless to say. G4B OU and G3JKB are well-known Dundee Kingsway Technical College RC HF members of the Verulam Com mittee. NFD station being operated by (I to r) GM3VEY, Photo G4EEI GM4BAG and GM4CUZ. Great concentration seems to indicate a difficult contact RADIO COMMUNICATION September 1977

William Munro (lnvergordon) Limited

distributors for NEC Amateur Radio Equip ment

NEC NEC

CQ110E Transceiver (Ex Stock) £645 plus VAT £80.63, Total £725.63 (Price includes Securicor Delivery)

Frequency Range 10m-15m -20m -40m -80m-160m and 11m and WWV 15MHz on receive only. Mode LSB—USB—C W—AM —FSK—FAX/SSTV Power Requirements 100/110/117/2001220/234 Volts AC or 13.5 Volts DC Input Power 280 watts PEP (240 watts on 28MHz)

Digital Readout—Separate Crystal Filters for each of LSB, USB, and CW. AC and DC power units are built in. Switched metering for "S" meter, Relative Output, Plate Current, and ALC for setting MIC Gain. The following accessories are supplied with the Transceiver-Microphone, DC Power Cable, AC Power Cable, 5 RCA Plugs, 2 Spare Fuses, 2 Jack Plugs, 2 Allen Keys and a 60 page instruction book. Built-in speaker with 3 watts output. A hybrid design utilising the best features of valves and semiconductors is used to give a high performance. 7 Valves-49 Transistors-19 FETs-128 Diodes-25 ICs. The use of the RCA low noise beam deflection valve (7360) as receiver mixer gives the CQ110E high sensitivity combined with remarkable crossmodulation characteristics.

CQ 301 2KW Linear Amplifier-10 to 160m with built-in power supply and 2 E1MAC 3-500Z Valves Ex-stock. £760 plus VAT £95, Total £855. (Price includes delivery)

SECONDHAND EQUIP MENT KW2000B with AC PSU £200 (incl. VAT) TRIO TS-510 with AC PSU £185 (incl. VAT) Please contact us for any specific item of equipment as our stock is continually moving.

We also stock Antennas and Accessories—Microwave Modules—Modular Communication Systems—Solid State Modules—Antex Products Components etc.

= 100 HIGH STREET, INVERGORDON, ROSS-SHIRE IV18 ODN. BARCLA Telephone 0349 852351 Telex 75265

HIRE PURCHASE INSURANCE ISSN 0033-780 EDITOR A. W. Hutchinson

Editorial assistant radio Mrs M. J. Collins communication Draughtsman D. E. Cole September 1977 Volume 53 No9 Secretary Mrs J. D. Brown C O N TEN TS 677 Current comment. QTC Contributions (including Members' Ads) and 680 A channel scanning arrangement for quartz crystals— all correspondence concerning the content of !. J. Dilworth, BSc, G3WRT Radio Communication should be addressed to: 684 Simple circuits for the beginner—R. S. McMillan, GM8JUY The Editor, RSGB, 687 Some experiments with high-frequency ladder crystal filters— 88 Broomfield Road, J. A. Hardcastle, G3JIR Chelmsford, Essex C M1 1SS 688 Calculation of distances from QTH Locator codes or latitude and longitude using scientific calculators—J. H. Bowen, CEng, Tel 0245 84938 MIERE, G8DET; R. C. Harvey, TEng (CEI), MITE, G4BBR; A. J. Harries 690 Technical topics—Pat Hawker, G3VA Correspondence concerning the distribution 695 Microwaves— Dain Evans, G3RPE of the journal and all other Society matters should be addressed to: 696 4-2-70—Graham Knight, GM8FFX

RSGB Headquarters, 698 RAE courses 35 Doughty St, London WC1N 2AE 699 A new look for the Radio Amateurs' Examination— R. J. Hughes, G3GVV. Tel 01-837 8888 Oscar news 700 The month on the air—John Allaway, G3FK M

ADVERTISING 703 Propagation predictions. HF propagation study

Advertising, other than Members' Ads, 704 Nominations for election to the 1978 RSGB Council should be sent to: Obituaries. Your opinion

Mr C. C. Lindsay, 705 Special event stations 2 Leyburn Gardens, They met at the palace Croydon, Surrey CRO 5NL 706 National field day 1977 results 709 Contest news Tel 01-688 5839 711 Club news 717 Looking ahead. Contests calendar Mobile rallies calendar EDITORIAL PANEL 718 Members' ads J. P. Hawker, G3VA R. F. Stevens, G2BVN 721 RSGB QSL Bureau sub-managers

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 members of the Society

ABC 20,432 copies per Closing date for contributions issue average unless otherwise notified: C) RADIO SOCIETY OF 1114.1.ateb circulation in 1976 4th of month preceding month of publication GREAT BRITAIN 1977

A • • _ - — • I South Midlands

•-••••• ESTA BLISHED 1958 19 YEARS SMC's TWO YEAR GUARANTEE ON YAESU SECURICOR "24 HOUR" DELIVERY FREE STOCKS —THE LARGEST IN THE U.K. Many may make this claim but we invite you to write for our stocklist and ask us first for your requirements.

SERVICE-REPAIRS, MAINTENANCE AND TESTING We have a comprehensively stocked, equipped, and staffed workshop to test all equipment before despatch and handle warranty work. SATISFACTION —YOURS (AND OURS) OUR AIM We consider that both parties should be contented with any transaction.

STABLE AND RESPONSIBLE DISTRIBUTION We believe that it is in the best long term interests of our dealers, our customers, and for the hobby, to provide the right equipment and maintain our services at a sensible price. We do, however, in the present difficult circumstances, reserve the right not to be undersold.

STUDY OUR LITERATURE STOP HERE FOR A COFFEE SHOP AT YOUR SINGLE-STOP SOURCE—S MC

THE FT221R, COMPLETE 2M STATION Ex-Stock

The FT22Iii. Tho muitimode USB. L513, A.M., F.M.. CW, (with semi-break•In and side tone). 2m trensceiver •••-•n- offering the choice of Phone locked VFO or 44 crystal channels, simplex or repeater (600Hz up and down shiltO with unique 'double push' auto tone burst, mains or 12V (3A) °Potation, excellent selectivity. SSS 2.4kHz (1.7: S.F.) or FM 12.kliz. Front panel adjustable VOX end mic gain, a calibrator (IMHz 10). lkHz readout and linearity sensitive squelch, clarifier with IRT and IRT with ITT (makes F.S.K. easy), swItchable "S" and centre zero tuning meter, noise blanker, serviceable plug in boards all contained in lle(14") e 5' il 11r, 2215, rigid package. 600j,Ht : ond 1.6MHz shifts over IMHz.

Now the YC221 digital readout unit for about £75 111011111•1111111m m mu m m FT221 R

- • THE FRG7, general coverage receiver Ex-Stock UNPARALLELED IN ITS CLASS AND ONLY £145 (VAT 121 %) Tho FRG7 loo general coverage solid stale receive, with specifications unparalleled in its price range- It uses a Barlow Wadley Triple-mix, drift cancelling loop for continuous, spin•tuned Inclusive coverage of 0.5 to 30MHz with calibration accuracy better than 5kHz. Frequency selection is accomplished by setting the RF (pre-selector and range switch), dialling up the required number of megahertz, then tuning the VFO knob as normal.

The receiver Is sensitive (0.5g11 for 10dB. S ,.. NIN (SSB)) and stable (within 500Hz for ano 30 mloutell otter warm up) with A.M., SSS and CW modes catered for. A 3 position audio filter, RF attenuate', dial lamp conservation switch, recorder and phone sockets are fitted, It Is mains powered, but should tr the supply fail, or portable operation be required, 8 dry cells are automatically switched in. The FT101E complete HF station—ex stock. The FT101E. A complete mains or 12e. OC station contained in a compact 301b. package, 260W, PIP of SSS (with in-built RF speech processor) 180W, CW and 80W or AM 10 10 160m (inc. 10 MHz RS). Tho sensitive and selechve (permeability tuned RF stages and 8 pole crystal filter) receiver afters: threshold adjustable noise blanker. switchable 25 and 100 kHz calibrator, tt 5k clarifier (with separate on/off switch), etc., etc. The VFO is stable and linear (readout to 1 kHz). external VFO or crystal control can be selected. with LEO Indi- cators Illuminated accordingly. Carrie' level is adlustabto for: tune up. AM and for CW Operation, whose performance with the semi break-in keying, with side tone, and the optional filter installed le of a high order. Linear and transverter provisions are made with sockets for: re/ay contacts, ALC output, all internal HT supplies, low level RF heater links nod switches, etc., etc.

New service manual for the FT101 series in stock £12.04). FT10IE SEND A LARGE (10 x 12) SAE or 15p STAMPS FOR YAESU CATALOGUE- STOCK PRICE- S'H LISTS, ETC.

SOUTH MIDLANDS COMMUNICATIONS LTD. EVENINGS —AGENTS —ALL QTHR OS B O R N E R O A D, T O T T O N Herd Office, S..2orirooms G3ZUL Stourbridge (03343) 5917 Brian Kennedy SO U T H A M P T O N, S O 4 4 D N ) Cables:Aerial Southampton GM8DOX B. el Allan (078683) 3223 Ian McKechnle Telex :477351 SNICO M M G G W3TMP Pontybodkln (035287) 816 Howartn Jones Hours of business: 9-5.30; 9-12.30 Saturday Tel :Totten (04216)7333 (31ines) GI3W WY Tandragee (0763) 710656 Mervyn Anderson

658 RADIO COMMUNICATION September 1977 Communications Ltd \e/ OF PR OFESSIO N AL EXPERIE N CE

TELOM AST WITH TA33 HA MTO W ER with TH3 Jnr. TELETO W ER with TH3 Mk. III TELESCOPIC GALVANISED SELF SUPPORTING TELESC OPIC GALVANISED

VERSATO WERS

TELESCOPIC IL TILTING SEE FAR RIGHT THE MAJORITY OF DELIVERIES ARE NO W MADE BY OUR O WN TRANSPORT.

Telescopic (20' sections) with lull tilling lacility allowing for easy antenna maintenance and altera - Irons. Tho relatively low unit weight and superior design et ground post allows easy and cheap InStallattan often without resorting to concrete. Large scale efficient production offers you e wide range ol towers at mmirnum cost 1+ 8% VAT, EX 10' telescope heavily galvanised Galvanised lattice 10' snobons. Carriage and rigging (RX) extra W ORKS) e.g. steel mast supplied with guy rings etc. or city lull rigging kit. Free standing with climbing stens. 42' £121,00 (R(4 £28) Standard P40 £212.00 Carriage £2-£7 ex-stock VAT 8% Carriage £3.£20 ex-stock 8% VAT 57' £174.00 IRK £28) Standard P60 £252.00 30' £25.00 or £43.85 cf., rigging 30' c/tv base grillage £192.35 79' £224.50 (R K £49) Heavy Duty 840 £286.00 40' £32.50 or £56.85 cjw rigging Heavy Duty P60 £313.00 50 ' £42.00 or £74.50 Ow rigging 40' ciw base grillage. P.O A 101' £303.50 ( K £76)

G WHIP HF MOBILE (Carriage 90p) VAT 126% HY GAIN HF R ANGE (Carr. extre) VAT 121% 7rd:tender 10-20m (± LF) £16.10 LF40. 80 Or 160 £4.87 BN81.l 1 1 lewd,: Balan £12.00 18AVT(WB10.80rn. Vert... £64.50 £44.40 MultImoblie 10/20( MM) £10 .00 MM40, SO or 160 .. £4.87 103BA 10m. 3 element .. £43.50 TH2MK11110-20m. 2 ele. Flexiwhip 10,1 FF) .. £13.35 FF15, 20, 40. 80 or 160 .. £5.04 153BA 15m. 3 element .. £54.50 TH3JNR 10-20m. 3 ele. £96.00 £137.00 Besemountj'hOle mount £2.65 Telescopic whip for cells £1.85 203BA 20m. 3 element .. £103.40 TH3MK11110-20m. 3 ele. 402BA 40m. 2 element .. £145.00 TH5DXX 10.20m. 6 ele. £164.50 CABLES RF FEEDERS (Carriage extra) VAT 8% 18V 10.80 Load Vert. .. £24.50 HY QUAD 10-20m. 2 ele. £151.80 UR67 5006m Heavy 36p yd UR39 75 ohm Medium .. 249 yd 12AVQ 10.20m. Trap Vert. £33.50 OB1015A 10.15m. 3 ale. £99.00 UR57 75ohm Heavy 429 yd T3278 75 ohm DI strIbution 20P rd 14AVQ 10-40m. Trap Vert. £47.30 HY TO WER Vet. £162.80 75 ohm Flat Twin .. 10p yd UR43 50 ohrn Solid Coal .. 16994 S M C TRAPPED DIPOLES (Post 45p) VAT 121% 300 ohm ribbon .. 129 el UR76 50ohm Strand Cent. 169 yd S SOOW P.I.P. 14 SWG.. £19.60 P500W P.I.P. Cu)Terylene GEM QUAD FIBREGLASS QUA D (Carriage £2-£9) VAT 12)% HP IK P.1.P. 14 SWG £21.75 braid city 75' feeder. etc. £21.75 GQ3E 2 elernent . £119.00 504E 4 element .. MOSLEY TRI -BAN D BEA MS (Carriago £3.50) VAT 12f % GQ3E 3 element . £178.00 CKIC) I ele. Cony. kit 74333 ele. 200W R.M.S. £85.00 I 1A322 °le. 300W. A.M. .. £58.50 M.USTANG 3 ele. .. £108.00 MUSTANG 2 ele. 1kW £87.59 AERIAL WIRE (Carriage extra) VAT 8% 14S WG hard drawn cu ..yd. 11p I 7(.044 cad ea standard ..yd. 20p AERIAL INSULATORS (poste.frovAT14% Cu terylene braid ..yd. 13p 7,036 cud eu standard . yd. 140 21* polyprop ribbed 18p SMCP1 8' carbon poltrgree £1.15 "T" porcelmn centre .. 38P 3' porcelain ribbed 38p ROTATORS Ex-Stock in Totten for fast delivery. VAT: Rotators 126%. Cable and daily. 8%. Carriage (ORS or post) FREE. SecurIcor delivery £1.25 extra (mainland). All rotators supplied complete with appropriate control box and instructions. CDE ROTORS STOLLE ROTOR AR20 Light VHF,UI-IF £32.00 AR30(111us. far left and centre) £39.50 AR22 VHF light HF .. £40.00 ARAD (Illus. left centre and near) £46.00 CD44" HAND II CDE AR33 AR33(de-luxe control ARAM .. £57.00 Bit Medium Duty.. .. £79.50 CD44 med. duty .. £95.ca 82100 Ham II heavy duty • . £129.04) BEARING STOLLE ROTORS 2010,220 Stolle though Rotator type £41.25 2030(220 De-Ime Stolle .. £45.50 BEARINGS CD562 CDE (up 10 e and I r rel.) LA 50 82100 Stolle (ball race) .. £10 00 MOUNTING KIT 2010 220 40121 Mounting plato £3.60 - and s Cual.T Box CABLE o LI. E 5 core-AR30(40(332030 -Per Wi• £0.22 A R20 30 AR30 40 A R22 40 33 8 core-CD44. Ham 11 -Per yd. £0.35

NORTHERN (LEEDS) BRANCH AMATEUR RADIO S.M.C. (Jack Tweedy) LTD Roger Baines, G3YBO Jack Tweedy G3ZY The Chambers, No. 3 The Parade (Chas H. Yourtg Ltd.) 79 Chatsworth Rd, Ham Stock. Roughtan Lane North Lane. Headingley. Leeds 170;172 Corporation St. Birmingham Chesterfield. Derby Woodh all Spa, Lines Tut: Leeds (05321 782326 Tel: 'Brum' (021)235 1635. Opon Mon -Set. 9-5 -30 Chat, fld (0246) 34982 Wrild Sea, (0526)52793 Open 9-5pm Tues-Saturday 9-8pm Thurs. Multi-slorey Car Park at Rear of shop. 9-5 Tees-Sat 9-5 Tuos-Sat ( - angt)

RADIO COMMUNICATION September 1977 659 -s"- / 1 / ,t \ 5 6 * 5 • • South Midlands TOTTON (HANTS. HQ), LEEDS, DERBYSHIRE

S M C THE NA ME FOU NDED ON SERVICE THE NAG 144XL LINEAR The NAG 144XL-220 is the finest 2m Linear Amplifier of its type we have yet seen. Identical in size to the FT-221 it produces about 250W RMS of clean stable output from a grounded grid 4CX 350F for a nominal 10W drive. The mains PSU using a large cut-core power transformer is built In and provides a 12V 3 area fully protected and stabilised output for 2IV only exciters. A swilchable. 10dB gnin, low noise Mosf et, receiver amplifier (filtered by a large three section helical filler), a largo coax change over relay, RF sensing (with adiustable delay) and manual control, an excellent directional coupler (for the inbuilt SWR bridge), thermal delay on switch on (anode current meter illu• mlnatod red for first 60 seconds), o thermal cut out situated in the valves exhaust stream (optical timer available to leave blower on for 90 seconds after switch oft), a grid current sensing ALC output socket, aro but a few of the star features. EX STOCK £355 + VA T. (121%)

Es DIGITAL II from KYOKUTO SCANNE R AN D CRYSTAL T.B. OPTIONS

Tho Digital 11 otters complete 5kHz slop coverage across 2 mettes and now with the Scanner 33, 25kHz channels from 145MHz upwards covered in around 10 seconds. It oflets full lock and lockout on all channels. The scanner stops on a required channel tot 10 seconds, then unless locked moves on. The bright digital readout comes from 6 seven segment LEDs. DIGITAL II, 1235: CRYSTAL TB, £10; SCANNER, £49.50 Selectable 10 or 1 watt output for simplex or duplex (up and down shifts), across ALL PRICES EXCLUDE VAT (12i %) 144-146 (rx to I49MHz) from a tiny 61' • 2' x 71'. Easily underdash mounted with the supplied mounting bracket, or slipped in place of the broadcost wireless. For strong handling, and low noise the R.F. mixer, fIrst I.F. (16-9MHz) second mixer (and LO) are all FET's. The frost end 19 tuned by varicaps by the DC output of the P.L.L. with superb selectivity provided by a 15 pole (±8kHz at —6dB ±151,11z at —70dB). Ceramic filter. LED lamps indicate if the P.L.L. Is unlocked or the squelch open. Tite V.C.O. Is directly modulated (for exceedingly linear deviation). Unitary 6 circuit block constiuction (for serviceebIlity and screening). Selective calling socket.

S OLID ST A TE M O BILE LINE A R S (UHF & VHF) FRO M KLM and A M PERE

2 or 70. Superb RF sensing and de blas nruinge- 2 metre. SSIINC WIFM, RF sensing with manual ments for all modes. Ciw mounting bracket 12V override. •Wicrostriptine" techniques

dc 10W drive 2-5' x 7-5" (8'51 12V D.C. tOW drive 2' x 6' o 10'011 ( VAT at 12111). free delivery. (VAT 12)%), free delivery. APB82A I45MHz 80W out £99.00 (Over 15 diflerent models—Sa y, details) APEI57A 432MHz 45W out £99.00 PA10(I60iBL 145MHz 160W output £160 APPOSA 432MHz 80W out £214.00

4 VHF HANDHELD VHF MONITOR RECEIVER KEN KP202 TRANSCEIVER SEIWA MR2 AND MS2 ( VAT Prices) 144MHz, FM, 2W of RF and 0 1/ of audio. Ideal for the SWL, the YL or even the XYL Immunity to image and IF breakthrough and as the monitor receiver to keep you in touch performance to rival all walkie-talkies and Tiny (2}" n 1) " 41") and light (8 ozs.) slip many a mobile sets. into your pocket or onto your belt with the C/w F plug, leather handle.'whIp case and optional case. Sensitive double conversion telescopic whip. Super1101 with 12kHz, band width, auto Fitted 6 channels S20 & S21 - choice squelch, and generous audio output cis' S (0 21 23, 24), R (3, 4, 5, 6, 7) £109.50. Nicads, Mains Charger. Earpiece, Antenna. R channel only crystal tone burst £10.00. MR2(4) 70MHz. 12 switched channels £53 Flexible stubby ant. £5.80 Case £4.90. MR2 144MHz. 12 switched channels £53 Base charger KCP2 £11.75 Ni cads £8.50. MS2 144MHz. 4 scanning channels £62 F to 1JHF adaptor £1.65 (all - V A T). Leather Case £1.90 Crystals each £2.00 ALL SMC BRA NCHES HAVE ON-LOC ATION SERVICIN G AN D CAN OFFER SECURIC OR DELIVERY SERVICES

SOUTH MIDLANDS COMMUNICATIONS LTD. EVENIN G — AGE N TS — ALL QTH R G3ZUL Stoutbridge (03843) 5917 Brian Kennedy OSB OR NE ROA D, TOTTON Hea:! Office. Showrooms GM(DOX B. 01 Allan (078683) 3223 tan McKechnie SOUTHA MP TON, SO4 ODN - , Cables: Aerial Southampton enee Telex:477351 smcomm G G W3TMP Pontybodkln (035287) 846 Howarth Jones Hours of business: 9-5.30: 6.12.30 Saturday - Tel: Totton (04216)7333(3 lines) GI3W WY Tandtagee (0763)840650 Mervyn Anderson

660 RADIO COM MUNICATION September 1977 Communications Ltd \& LIN CS., BIR MIN G H A M. Agents: N.I., SCOTLA N D & WALES YAESLI

MICRO WAVE MODULES-SPECIAL OFFER ''-'1 ALL PRICES ARE W ORLD WIDE POST FREE (H- VAT U.K. ONLY) (personal cheques, money orders, master charge, Viza etc) MM A70 4M Pre Amp, Two isolated outputs £13.00 MMC432/** 70cm Converter 14, 18 28, 144 MHz IF £22.00 70cm Converter 51 MHz IF for TV £23.00 MMC70/** 4M Converter. 4, 14. 18. 28 MHz IF £18.00 MMC435151 70cm Transverter 28 or 50 MHz 10W £97.00 MMC701••/1-0 4M Cony. 28, 50 MHz IF with LO out £20.00 MM432r* MMT432/141 70cm Transverter Dble convsn. 10W £13.00 MA A144 2M Pre Amp. Two isolated outputs £13.00 MMC1296i••• 23cm Converter 28 or 50 or 144MHz £25.00 MMC1441** 2M Converter 12, 14, 18, 24 MHz IF £18.00 MMV1296 23cm Tripler varactor 30W input £30.00 MMC144)* 2M Converter 2 or 4 MHz IF Dble cony. £8.00 MMD050 Freq. counter miniature 50 MHz 12V £62.00 MMC144/**L0 2M Cony. 28 or 50MHz IF 5 mW LO out £20.00 MMD050,I500 As the 050 but to 500 MHz £79.00 MMT144r• 2M Transverter 28 or 50 MHz 10W out £19.00 MMD500P Divide by 10 12V 2•5V pp output £25.00 Coax Slide Switches SMC-HS VHF Antennas Up to : I kW, 1-5 GHz, (1-3dB less, 1-2 : 1 VSWR, (VAT 12)% Car. 9571 50dB Isolation. 50 ohm "N" or "PL" fittings. Ex- Stock P. & P. 30p (VAT I- 8%) 250 (29 or 145 MHz) eflective DC short, TW2S10 1 in 2 out nickel 50239.. £5.40 snap mount, matching transformer, shock TWSI50 1 In 5 out nickel S0239.. £11.50 spring, tapered whip. c/w 12" cable and PL259 TWS220 2 In 4 out nickel S0239.. £11.50 plug ONLY £11.75 GDXI 80 to 480MHz Obscene, omnidirec- Coax Relays tional, 3dB5-• Excellent VSWA £37.50 12v DC 50 ohms. Silver plated. 4 weeks. 260 ("70 or 145 MHz) High gain, gutter mount, L P. zap (VAT + 8 %) tapered coil end whip, two spring fold over Power crosstalk (at 500 MHz) feint £17.15 CX120 50W 35dB Cable entry £9.50 25 Trunk lip mount for snap bases £2.95 CX230 300W 40dB BNC sockets £17.90 265 Gutter clip all. angle.. £3.95 CX600 N 600W 40dB N sockets £21.50 111 Gutter clip base, cbiz shock spring, 10' 250 260 Cable, PL259. etc £4.95 JAYBEA M 70 (4m), 144 (2m) 432 (70) (Carr. about £1) VAT 121% 05 ,2m 5 over 5 slot feed ..£11.00 PBMI0/2m 'eel° Para £20.50 CUSHCRAFT VHF OMNI (Can. 90p) VAT 121% 138/2m Ovoyb slot feed .. £14.75 PBM1412m 14 ele Para ••: Ringo Ranger ARX 6d8 gain (over 1) ultra low angle radiation. excellent 50 5XY/2m 5 element crossed £12.90 D8/70 8 over slot react £12.50 ohm match. Uses 3 o (A in phase and p stub. 145MHz version awes 9' 6' 5XY/2m 6 element crossed £16.10 PBM 18170 18 ele Pare • • £15.00 (a 11113s) 432MHz menu 3' 6' (illus. left) 10XY2m 10 element crossed £21.30 MBM48/70 46 ale Mull I •. £17•50 ARX2 Ringo Ranger 145MHz £21.50 ARX450 Ringo Ranger 432MHz £21•50 5Y/2m 5 element yag I £6.20 MBM88/70 88 el e Multi •. £23.40 AR2 3dB Ringo Vert .. £12.75 ABW144 2m Blg Wheel .. £14.50 SY/2m 8 element yag I £8•10 12XY/70 12 el e crossed .. £2440 AR25 ORO AR2 £15.00 ABWI2S ABW harness .. £7.30 10W/Om 10 ele long yogi • • £17.20 4YHm element yag I •. £10.20 CX1000 29MHz Ringo .. £25.75 ASQ1 2m Squat° .• £11.7 5 I4Y/2m ale longyagt • • £7.2.00 PMH2/70 2 way harness • • £4:75 0412m element yogi £13.20 PMH2/CCirc. phasing •. £4•10 COAX PLUGS cpa, P 30P) VAT 8% 06/2m 6 element quad • . £17.60 PMH212m 2 way harness . £5.50 P1259 Standard UHF Plug £0.49 258 Back to back female £0.80 UG175 Reducer UR43R6 £0.12 Back to back male £1.20 BANTEX VHF WHIPS (Carriage 90P) VAT 121% 00176 Reducer UR70 £0.12 'T' Adapt (2F1M) £1.20 Bol 145M1-Ir .. .. £6.35 705 ) 70MHz .. £4.00 PL259R Fin reducer plug 58CU £0.56 'T' Adapt (3F) £1.48 BOA f.g. 2n, fibreOlaSS £3.75 Trunk Lip Mount .. £5.75 PL259S "Solderions" UHF UR76 £0.51 Angle K(o.,+ 1F) £0.90 BOA s s.( 2m stainless steal £8.50 Magnetic Base Mount .. £8.50 P12595 "Solderless" UHF LIR67 £0.51 239 Socket to Phonolcar £0.60 B5U I 432MHr £5.00 Standard base unwanted deduct £0.50 P1259P Push fit UHF - £0.69 239 Socket to 3.5mm Jk £0.70 144-1 I 145FG or SS .. £3.50 UCL Mid loaded .. £0.00 S0239 4 hole socket £0.40 50230 2 hole socket £0.37 Crystal Filters and Crystals only £3.75 a pair (P & P 20p VAT 124%) YA 05M OTHERS TF30F350 350Hz F•101 CW Sol £19.80 YE W TF30H350 350Hz F*101 CW Opt £20.75 FT2F. FT2F21, FT2AUTO, FT224. TR7200(GX), CI46A. CS266IB, TF30F600 600Hz F•101 CW 6p1 £19.00 FT223 (B. 12, 18 MHz Tx, 14. 44, MS2, MFt2. (12 MHz Tx and Inc. TF301112 12kFix F•101 FM Bel £20.75 52 MHz Rn). 44 MHz Ru). TF90H601) 600Hz 9MHz CW 8p1 £16.00 SIMPLEX S (0, 20-24) SIMPLEX S (0, 12, 16, 19. 20-24). TF110F2-4 2-4kHz 9MHz SSB 601 £16.00 DUPLEX R(3-7) at least. A large TF90H12 12kHz 9MHz FM Eel £18.00 DUPLEX R (0-9) end IR (0-9) T selection of Inverse receive TF107H600 600Hz 10-7MHzC W Opt £10.00 R. crystals. YF107H2-4 2-4kHz 10-7MHzSSEMpl £16.00 FT200B, FT301(S), FT221(R). CONVERTER CRYSTALS £2.20 YFIO7H12 12kHz 10-7MH:FM Sol £19.00 FT101 (EX), FT75(B), FR101(S) 38.66612m). 42(4m.), 505 all £2.20 each. (70cm.). Carrier crystals (9 or 10-7MHz) HCIWU ea. £2 A POS TSCRIPT As you may have seen on television, radio, in the newspapers or in last month's ad, we suffered a severe fire which destroyed the majority of our stocks of antennas and fittings here in Totton. We are glad to report that we have succeeded in replacing the bulk of our stock lost in the fire and that the staff have now returned to their normal duties. We apologise for any Inconvenience this disruption may have caused and would like to thank customers and friends who arrived with boiler suits and guns boots to help and for the messages of sympathy and offers of assistance from suppliers and our direct trade competitors alike.

NORT HE RN (LEEDS) BRANC H A MATE U R RA DIO S.M.C. (Jack Tweedy) LTD Roger Baines. GlYBO Jack Tweedy. G3ZY Tho Chambers, No. 3 The Parade (Chas H. Y o ung Ltd.) 79 Chatsworth Rd. Ham Shack, Roughton Lane, 170/172 Corporation St. Birmingham North Lane, Headingley. Leeds Chesterfield, Derby Woodhall Spa, Lines Tel: Leeds (0532) 782326 Tel: 'Brum' (021)236 1635. Open Mon-Sat, 9-5.30 Ch staid (0246) 34082 W WII Spa. (0525)52793 Open 11-5pm Tues -Saturday 9-8pm Thurs. Mulii-stotey Co, Perk at Rear of shop. 9-5 Tues-Sat 9-5 Tuns-Sat (-,- appl)

RADIO COMMUNICATION September 1977 661 LO WE ELECTRONICS LTD IN LONDON comm U NICATIO NS HO USE, WALLINGTO N SH,WALLINGT ON,SURREY.01-669 6700

Stop turning the pages— You have just reached the good stuff!

NO' '410 'TRI O TR7500, £225 inc VAT. And no more crystals to buy—ever!

We are delighted to announce the imminent arrival of the newest addition to the exclusive TRIO range of top qualify transceivers—the TR7500 2 metre FM mobile/fixed station. The TR7500 fits info the TRIO product line above the established favourite. the TR72006 which continues in production of course. Following the TRIO policy of "getting it right first time", the TR7500 has been the subject of a long development study, and as a result offers features to cover all user needs. TRIO attention to detail is evident in areas such as the LED channel display which shows correct channel numbering, i.e. 20 when on S20, 4 when on R4, 0 when on SO etc. Easy to see by day, and a positive safety feature when mobile at night, the TR7500 display removes the need to remember, "did I programme R6 into channel 15 or channel 20 ?- Incidentally. the photograph is of the American market version of the TR7500 and as the American channelling is different to ours, TRIO arrange the display to suit !hem, hence the number 94 display. Typical of the TRIO attention to detail again. The design of the TR7500 is based on an advanced phase locked synthesizer which le ready programmed to provide all 40 channels from 145-146MHz with no further hand wiring required. Channel selection is by a single knob and simplex, repeater and full reverse repealer operation are fatted as standard, together with automatic tone burst and high/low power switching. The TR7500 is a little larger than the TR2200 and should therefore fit into most mobile situations. The usual TRIO accessories such as the mobile mount, microphone, power leads etc aro of course provided with the rig. The transmitter power will be well in excess of 10 watts and if the reports from Japan are correct, the receiver section should sot new standards for this type of equipment. I was asked in a recent open advertisement "could you do better than 7 7 7". In view of the TR7500, my answer must be "yes, I can l" NRD 505 - A NE W DIMENSION

The NR0505 uses very advanced techniques for providing exceptional strong signet handling characteristics. the Input to the receiver first passing through a 95MHz roofing filler to a bank of automatically selected band pass filters (thereby removing the requirement for a preselector control) to a further 95MHz low pass filter. AGC control is then applied using a PIN diode attenuate( before the signal is passed to a fully balanced RF amplifier. Up conversion to the first IF of 70511is la carried calina balanced mixer followed by a 70MHz crystal filter. The first oscillator signal is derived from a phase locked drift cancelling tools system incorporating the signal from the PTO VFO, to allow tuning over any 1MHz range. The annela phase locked oscillator system generates a clean, noise free infection signal free from miser products and the strong unwanted signals every 1MHz which occur in receivers such as the FRG7 and Barlow-Wadley. Typical of the advanced design is the use of automatic amplitude levelling of the oscillator Injection to the mixer. Second conversion is then carried out to an IF of 455kHz at which final IF bandwidth is determined. A high performance noise blanker is included in the IF system end active audio filtering matches the AF bandwidth to the signal characteristics. A 600ohm line feed and a 75ohm 455kHz IF output aro provided for remote operation or diversity use. For CW use, the BFO is tunable over a 5kHz range and (11 control allows receiver tuning Let me begin bY stating that the NR0505 is not a receiver for the amateur—at around over a similar range even when locked to ono of the stored frequencies. £1.600, how could II be. For the professional or those of you who can dig deep for the A separate high performance PLL system generates an output signal locked to the best receiver you ever laid hands on, the NR0505 le the one for you. What does it do '7 VFO, which will drive an associated transmitter or transceiver. Frequency ranges Read on: available (on ordering) will suit most Japanese or American transmitters and The NR0505 covers the range 1C0kHz to 30MHz in thirty bands each 1MHz wide using transceivers. a high performance up conversion system incorporating a significant advance on It gees without saying lhat the construction of the NRD505 is to the very highest previous dill t cancelling techniques. All modes of operation are provided, with appro- standards and full use t s made of the latest high speed Schottky and CMOS devices, priate filters for each modo end corresponding detectors. A unique feature of the together with printed wiring looms for Posible connections. NRD505 is the provision of four random access memories into which any frequency to The NR0505 delighted our jaded senses when we used tier the first time and we are which the receiver Is tuned can be placed by simply depressing a front panel button. of the opinion that it is significantly bettor than any receiver which we have used before Al any subsequent time, regardless of the frequency to which the receiver may be including such exotica as the Collins 51-S1 and the latest Recut receivers. tuned, any of the four stored frequencies can be instantly selected for monitoring. The If you want to see the NR0505, it Is now on show at Matlock but you'll have to fight store contents aro held even when the receiver is switched ofl and disconnected from your way through the crowd. It will of course be prominently displayed at this year's any supply. Leicester show. See it soon.

LO WE ELECTRONICS LTD IN LEEDS 27 CO OKRIDGE STREET, LEEDS. 0532-452657

662 RADIO COMMUNICATION September 1977 LO WE ELECTRONICS IN BIR MINGH A M 362-4 SOH O ROAD, HANDS W ORTH, BIRMING HAM. Tel 021-554 0708

••• ' T R I O WHEN QUALITY COUNTS ABOVE ALL ELSE FT R. I CO

TR-2200G X T R-3200 The TR2200GX represents the very best of TRIO The TR3200 from TRIO. Not content with having the lead in 2 metre handy portables. TRIO have gone design. It is the latest in the bile of continuous pro- a step forward and produced the best 70cm portable to match, cress from the first TR2200 and maintains the TRIO The TR3200 is a really terrific rig: over 2W out, with switched reduction to 400m W for local con. tradition of lop rurality at a reasonable price. The !acts; tailored speech response with a new limiting amplifier and new microphone, elves the crisp TR2200GX has all the features that you would want-. speech quality you like. high power output: sensitive receiver: flexible use Excellent receiver performance with double IF filleting at 10•71.4Hz and 455kHz with no less than from internal batteries or external power tieing the five limitera to guarantee noise free performance on even the weakest signals. lead supplied: built in removable telescopic antenna 12 channel capability with three channels fitted.(SU8.18,20.) Supplied complete with all the usual with flexible whip available: built in metering of accessories as the TR2200GX and including the new 510 wave high gain removable antenna. signal strength, transmit output and battery candi- Tif-3200 filled 3 ch. £171 Inc VAT. hen: fitted with twelve channels at low, low prices. VS-3200 lOW amp. and RX pre-amp £40 MBIA mobile mount £9.43 NI-cad pack £9.72 in short, all that you could want. All operator controls are placed for maximum convenience on the top face of the rig and a protec- ______.-----'------7 ( , . tive carrying case is Included In the price. MINA mount Tee matching accessories include a tOW amplifier y for moblle use, which incorporates SWR protection and a regulated supply for the TR2200GX: a quick release mobile mount and a low cost rechargeable •_- ..._•-!' ••ei battery pack. TR-2200G X filled 12 ch. £160 Inc VAT ...... '..e------VB-2200GX lOW amp £43 Inc VAT i›,i • MBIA mobile mount £9.45 Nicad pack £9.72 4,4 , f The VB2200GX Is the matching IOW mobile :1 0 1 1 amplifier for the . if TR2200GX. It will also match any of the pro- em-zero vious TR2200 series equipment. Small sloe en HI MNieet .111111t21 and low weight for easy Don't forget, the following accessories are ve.2244)Ou fitting in any vehicle provided with the TR2200GX and TR3200 .r... ---.. malte the VB2200GX a Removable antenna free must for the operator Carrying case free • ••- — 18z '-'1 who wants the very best Shoulder strap free l ofall worlds, portable Battery charger free 4. and mobile. External power lead free

FEATURES Antenna impedance: 50-75 ohme. unbalanced Following are a few of the TS-820s many exciting . Carrier suppression: Better than 40dB features. _ _ .. .-,4.7.,... - ii.....t". (i,)r,..- . Sideband suppression: Better lhan SOdB SPEECH PROCESSOR • An l'IF circuit pro- ...... - . _. an _60. „, cHnr. vales quick time constant compression using a ''' parlous radiation : Grenier than — monies more than -40dB) true RF compressor as opposed to an IF clipper. .1-...... r...,.. . .: — r --. ,, r'.- Amount of compression Is adjustable 10 the Receive sssss ilivity:Betterthan0•2µV r.C.:'-'.:- rz.=-1 • desired level by a convenient front panel control. ....-. Receiver selectivity: SSE; 2•41tliz (--19d8) '_ .•_"7:14 •:.- •-;•«•H - a. _ IF SHIFT • The IF SHIFT control varies the IF 4•41cHz (-60rIB) a ensaband without changing the receive frequency. CW • 0•5kHZ (--tiriB) Ct•l... .."•:':..., Enables tho operetor to eliminate unwonted 1.1>Hz (-60d15) - • aignals by moving them out of the paesband of the • With optional CW filter installed. receiver. This leaturo alone makes the TS-820 the Image ratio: 160-15 metres: Better than GOdB pacesetter that it la. 10 metres: Better than 50d8

PLL • The TS-820 employs the latest phase lock IF rejection: Better than 80dB 4,, 0 a TS-820 loop circuitry. The single conversion receiver Power requirements: 1204220 VAC. 5060Hz. .e. rr n 1 section performance otters superb protection 13-8 VDC (with optional DS-1A againet unwanted cross-modulation. And now, DC-QC converter) The ultimate transceiver... TRIO'S TS-820. No matter what you PLL allowsthe frequency totemain ihesama when own now, a move to the TS•820 is your best move. It offers a switching sidebande ans. LSB. CW) and Rower ConaliMPtion: Transmit: 280W. Receive: degree of quality and dependability second 10 none, and as the eliminates having to reCallbrate oath lime. 28W (heaters off)

owners of this superb unit, you will have at your finger-tips the Dimensions: 132'w a 8' h 13,,,* d combination of controls and features that, even under the SPECIFICATIONS toughest operating conditions, make the TS-820 the leader Weight:35.2lb (18kg) that it is. Frequency range: 1.8-30MHz (160-10 metres) Unprecedented demand plus the painstaking care TRIO lavishes Modes: USB, LSB, CW. FSK T S-820 £625 inc VA T on each TS-820 created an lethal backlog of orders, but happily InPul Powers: 200W PEP on SSS we ran now supply the TS•820 from stock. Once you have °per- 160W DC on CW 0 G-1 optional digital readout oled the TS-820 you will not be satisfied with anything else. 100W DC on FSK £1 2 6 in c VA T

HEAD OFFICE 119 CAVENDISH ROAD. MATLOCK, DERBYSHIRE. Tel (0629) 2817 or 2430.9 a.m. to 9 P•m. (NOTE: ALL MAIL ORDERS TO MATLOCK. PLEASE) AGENTS Alan GW3YSA, 35 Pen-Y-Waun. Oeil 'sat, hr. Pontypridd. Tel. Newtown Llantwit 3888 Send 48p in stamps for lull cato' EVENINGS AND John GJJYG. 16 Harvard Road, !boomer, Levees. Sussex. Tel. Rinerner 812071 logue, price lists and our antenna WEEKENDS S/m GM3SAN. 19 Ellis/nun Road, Bailtleston, NI% Glasgow. Tel. 041-771 0364 booklet

RADIO COMMUNICATION September 1977 663 PAUL G3VJF IC OM

Can you listen on the input channel at the flick of a switch? The IC-240 is still the best value in synthesised transceivers

£198 INC VAT

DIMENSIONS 6.15" wide 2.28" high 8.59" deep

IC-240 THE W ORLDBEATER FOR FM MOBILE

THERE ARE SEVERAL CHEAPER ALTERNATIVES BUT IF YOU LOOK CAREFULLY INTO IT YOU WILL FIND THAT TO BUY ONE IS FALSE ECON OMY

* Can bo easily program med to any channel of your choice. The IC-240 Contains * Eaoallant modulation and clipping. The modulation and clipping an the IC-240 a synthesiser instead el banks of crystals. This Contains a programmable divider are designed to provide a high quality, easy to read. signal without over doubting. which can be programmed by YOU for each of the 22 channel positions merely Mane eetli neglect this point with the result that you either have to turn up the mod by putting diodes in tho appropriate places as indicated by a chart provided in the to be read at all, and then find that you over-deviate on peaks, or you keep the handbook. deviation down and aro accused of mumblIngl The ICOM quality of modulation is well known and is hard to beat. * quick, easy .election of channels. Tho IC-240 has a single knob, 22 position, channel selector. Anyone who drives in traffic and wants to change from one popular channel lo another knows the problems of channel changing when Ibis * Really solid construction. There is nothing cheap and nasty about the 1C-240. Involves several knobs or even a single one when it has lo be used in conjunction It is a really solidly built piece of gear which is highly reliable. 01 the hundred• with a digital display which requires peering at. already sold very few had lo como back for repair under warranty, their record in * Instant facility for listening on all repeater input channels at the flick of a this respect being much better than many crystal controlled sets. switch. It Is a tremendous advantage to be able lo listen on the INPUT channel of a repealer In order to determine whether a direct OSO is possible. With the 1C-240 this is possible merely by flicking the control switch on the front panel from * Automatic PA protection. The PA has a continuously satiable PA protection OUP to SIM. system which gradually cuts down the output power as the set is fed lelo a worse VS WR. * Built in tone burst which can be completely automatic. The tone burst Is easily made automatic so that the tono Is placed al the beginning of each transmission when on Duplex. This Ise necessary feature while some UK repeaters need feeding * Very adaptable for adding a cheaply constructed scanner to cover the whole with a tone at Ihp beginning of each over rather than only for Initial opening as Pm band. Tho greatest asset of the IC-240 is the may 11 lends Itself lo the mead- recommended by the RSGB. We do this mod for you if you buy from a THANET menter In digital logic. it Is easy to design peripheral equipment lode interesting agent or shop. things such as scan the band or provide other frequencies which are not Oro. * Second-to-none receiver. The receiver on the IC-240 Is really sensitive. Simply gramrned into the set already. Several circuits for scanners will no doubt be compering maker's specs will not glve you the true picture. The re-designed published shortly and we hope to be able to otter a klt for a scanner with six digit discriminator circuit makes the 240 by lorgnent the best receivers on the market. frequency display for something in the region of £20. You can soon spend this on Ask someone who hns onel crystalst

IT WILL HAVE TO BE AN IC-240 FROM THANET - YOUR ICO M SUPPLIERS

FOR DETAILS LEAVE YOUR NA ME AND ADDRESS OR CALLSIGN ON OUR ANSAFONE (02273 63850) DURING THE EVENING WHEN CALLS ARE CHEAP HP TERMS NOW AVAILABLE

YOUR SOLE AUTHORISED UK IMPORTER FOR ICOM Access Accegs THANET ELECTRONICS Al al k 143 Reculver Road, Beltinge, Herne Bay, Kent (02273 631159)

664 RADIO COMMUNICATION September 1977 -e• DAVE IC OM G4ELP

T WO LITTLE QS0 GRABBERS

THE PORTABLE PAIR THAT ARE A PLEASURE TO HAN DLE— AND HARD TO BEAT

IC-202 SSB IC-215 FM

T WO RELIABLE LITTLE PORTABLES WITH SENSIBLE BATTERIES AND A USEFUL OUTPUT PO WER.

Both the IC-202 and its FM brother the IC-215 give a useful 3 Watts output and run from C type cells, which are about 4 times bigger than the penlight cells used in other portables and give correspondingly longer life. Both exhibit the high quality found in other ICOM equipment both in construction and In excellent transmission. Ask anyone who has one and he will tell you just how good they really are.

NE WS ABOU T THE IC-211E and IC-245E

As many of you know the IC-211E and IC-254E have proved so popular throughout the world that there is a worldwide waiting list for them. We have just had a message from Japan to say that they have managed to increase their output considerably and we therefore hope that the situation will improve shortly. However it is still a good idea to get your name down as soon as possible if you are thinking of buying one of these excellent rigs.

IF YOU LIVE IN THE NORTH WHY NO T VISIT IAN AT

64 HIGH ST., WO MB WELL. YORKS. THANET NORTHER N TELEPH ONE: (0226) 756229

see page 650 of last month's issue for a map.

T H A NE T A GE N T S

LOND ON —Terry GlIBAM (01-5689366} NORFOLK —Ted G3FE W (05088632) MIDLAN DS—Tony GBAVH (021 329 2305) SCOTLAN D—Inn GM8DOX (07868 32231 W ALES —Tony GW3FKO (0222 702982) NORTH WEST—Gordon G3LEQ(Knuteford (0565) 4040)

FOR ALL MAIL ORDERS AND SALES DURING BUSINESS HOURS

FRO M THANET ELECTRONICS IC OM HERNE BAY

RADIO COM MUNICATION September 1977 665

B • • FREE PACKET OF CORNFLAKES WITH EVERY PLASTIC MODEL! — well, not quite, as both are a little out of our line — HO WEVER ... If you don't like cornflakes. how about a BUT, you may say: "What's the catch?" FREE FT101EP Us: "Funny you should say that! We did have a condition or two in mind." (That's right --THE original and genuine YAESU M USEN, world-renowned all-band HF transceiver "Ohl— What's to do then to qualify?" to full specification) Us: "Fork out £399 plus VAT (£4.18,87) for o PM 2000 (see PI112000 FEAT U RES below left) and we'll send you that and a brand new, fully guaranteed FT101E as well!" Accurate measurement of: * PEAK ENVELOPE PO WER ON SSB "Well, why not just say 'FREE PM2000 with every FT101E'?" * RMS WATTS ON CW * SWR Us: "OK —if you insist. Here goes." Price £48.60 (without FT101E 1)

FREE W estern PEAK READING WATTMETER WITH EACH FT101E at

£448.87 INCV (£399 exc) LP24noll et period

5-WAY ANTENN A S WITCH MODEL AS W-1

* Handles 1.2 We * Earths antennas not In use * Fitted YAESU Style knob. * Mounting holes for wall or equipment. von (Incl VAT(P.&P.)

AND HERE'S AN OTHER OFFER YO U CAN N OT MISS THE FDK MULT-2000 2m. SSB,F M,C W 202 Ch. SYNTHESISED AC DC TRANSCEIVER

* Full cover 144-6MHz. * VX0 gives lull coverage between 10kilz Spacing * Rapid change of frequency and mode is possible * RIT (Receiver Incremental TunIngl allows receiver to be tuned without moving the transmit frequency. * 603kHz Repeater shill works on ell frequencies. * Tone access built.ln. * Filled narrow FM filter.

Offer Price only £299 inc. VAT!

666 RADIO COMMUNICATION September 1977 Electionics (UK) ltd

Elevate.. . with the W estower . "the STRON GER ONE"

* STANDARD TYPES, RATED AT 75 MPH WITH FULL LOAD QUOTED * HEAVY DUTY TYPES, RATED AT 100 MPH * MODELS FROM 25-119'. ALL TELESCOPE DO WN AND TILT OVER. * MODELS FOR ALL SOIL CONDITIONS, WITH/WITHOUT CONCRETE. * DESIGNED BY CHARTERED ENGINEERS TO BRITISH STANDARDS. * CONSTRUCTED OF HIGH QUALITY SPECIAL ALLOY STEEL. * STANDARD MODEL 40% STRONGER THAN SIMILAR TYPES.

A Heavy Duty is well worth the extra... Compare ...

Size Head Load at 75mph Price (inc. VAT) 3S (58ft) 125 lbs. £322.92 3HD (58ft) 250 I bs. £383.40 4S(75ft) 35 lbs. £410.40 4HD (75ft) 66 lbs. £452.52

Head Loads are for unguyed towers. Prices are for framed-post models (FP) and are carriage paid except to Scotland, Devon and Cornwall. Over-water deliveries also extra.

Heavy Duty is up to 100 ()/ stronger than Standard

Other WESTERN Products.... (Prices inc. post and VAT)

DX-33 3 band (10, 15, 20m) 3-element beam, 2kW pep £84.37 BA-1 1:1 Balun, 1kW rated, S0239 socket £5.91 AT-40 40m, dipole traps, 1kW rated (per pair) £5.91

CONNECTORS: WE-588 (S0239) UHF coax socket (single-hole) 27p. Plus 32p post up to 10 items. 50p over 10. Over 50 WE-592 L-Adapter for UHF connector, 86p 1 WE-596 UHF-to-Phono Adapter 27p f items post free.

STOP PRESS!! PM2001 VHF PEP meter coming— WATCH THIS SPACE

Agents: LES LYSKE. Gl3CDF. NEWTO WNARDS (0247) 012449 ALAN CAMERON. GM3OGJ ALLOA (0259) 214653 Westorn Elactroniu (t11) Ltd ALAN PAXTON. G4BIZ. (0,215) 654715 HEAD OFFICE (ALL Mail,Enquiraes) SHO WROO MS al LOUTH: Opon 9-12, 1-5 pdn. MON.-FRI. Sat. by appolnimenI. FAIRFIELD ESTATE SOUTH AMPTON —closod

LEICESTER: MAY'S HI-Fl. CHURCHGATE. Tel. 58662, OPW , LOUTH, LINOS, LN11 OJH cr.', Louth (0501) 4955 6) MON. -SAT. 9.6 pan., CLOSED THURS.

RADIO COMMUNICATION September 1977 667 W ATERS & STANTON TELEPHONE HOCKLEY (03 704) 6835 (2 LINES

UHF FM? THE NUMBER ONE CHOICE MULTI-Ull Note receiver incremental tuning is an absolute must on 70cms— 12Watts output some transmitters are not quite as stable as the U-11! 23 channels (9 fitted) 4 Autoscan channels Receiver incremental FDK for 70 cms Multi-Ull tuning Automatic tone-burst mi c brackets, STOP PRESS power cord etc—£249 Mosley Super TA33 inc Vat and delivery. High Power Beams In stock complete with balun 10-15- 20m £110 delivered free.

FDK QU ARTZ 16 10 channels fitted (25 channel capability) FITTED 9 channels & tone-burst QUARTZ-16... SAVE £30 Never before has such value tn 2M FM been offered al such a low price. Exactly the some power output (perhaps o 11111e more in some cases!) receiver sensitivity and size as its competitors but £30 cheaper. What's moro It ls supplied with 20 Mats giving you complete absence of spurious ix and rx responses whilst (Wring You the ehillty to add any channel frequency at a later date whether it be 254tHz or 121 spacing. You also get a microphone, mounttng bracket, power cord etc! Beat that for value. £I69 inc Carr & VAT FDK for 2 metres Multi-II IF YOU MUS T SPEN D AN OTHER £30 OR SO - - -. then wu think you have a right to expect a low additional features. Compare the Multi-11 with any other model. Does il houe:- 23 channels plus 4 auto-scan: receiver Incremental tuning; to monitor switch tar audio and frequency checking; built-In d pre-amp tor 20d8 quieting al (slur: 12 watts output minimum, remote vfo socket; centre-zero and S.meter: channels fitted Indicator light? If it does then it must be another M-il ...lilt doesn't perhaps you'd better buy a quartz-16 and save £301 FDK Multi-2700 Mk II

Fitted 7 channels & tone-burst £209 inc. VAT. Additional 3 channels £10. YOU DON T HAVE TO SPEN D £489 FOR M2700 PERFOR MANCE Although we sell many Mull, 2700 transceueers we have to adnui that you can buy Other 2 metre all-mode rigs at loss than £489. In fact for around £380 wo can sell you other models having all-modes and complete coverage of 2 metres. Of course you'll have to buy one or two extras to match the Multi 2700 performance. Tho vox unit may be extra—not a lot—perhaps £20 or no; the speech prOcessor is a must at about £50; you'll have to purchase the synthesizer unit to really appreciate the benefits of Its SEP TEMBER OFFER clear digital readout and Instant OSY facility—let's be conservative and say £00 to Want all modes 2m or 70cms During September we are offer- £100 should cover this item; for low power you can modify the rip (be careful not to do it until the guarantee has gun out) fairly simply: the OSCAR conveder works out ing the M2700 plus the MM W 144/432 transverter at £599 Inc quite reasonably at £20 and a simple switch mounted on the front panel plus a relay VAT! Is all that is needed for instant selection; finally you will find Ihnt the receive pre-send Act now and save £'s. at £10 will make a World of difference. So for £350 plus about £200 you can match the performance of the Multi-2700. For £100 less you can have the real thIngl

668 RADIO COMMUNICATION September 1977 S FAST MAIL ORDER ELECTRONIC SERVICE FDK TELEX 897406

HA M RADIO'S

LARGEST STOCKS IN THE SO UTH LARGEST MAIL ORDER SERVICE IN THE UK

To order:- BY POST Simply write, giving details of your requirements and including a cheque, postal order or credit card no. for instant despatch. BY PHONE Dial 03 704 (Hockley) 6835 giving your requirements and quoting your credit card number. No fuss! Your goods will be on the way the same day! PERSONAL CALLERS Why not take a trip by rail (2 mins from station), by car (our own 50 car carpark) by air (10 mins from Southend Airport) and brouse over our stocks. OVERSEAS CUSTOMERS. We export daily to most Euro- pean countries. All documentation Is taken care of by our office staff and deliveries can be made to you by road sea or air.

JUST PART OF OUR EXTENSIVE STOCKS A S K A B O U T O U R INS T A N T CRE DIT SC HE ME JAYBEA M VHF,UHF ANTENNAS MASTS MIC ROWAVE MODULES 4M ANTENNAS SPM 16' Portable mast £9.45 (1.25) MMT432J28 rensverter • £11)9.10 (n.c.) 4Y/4M 4 el yogi £11.45 (1.75) PME 4' mast extentlon £1.07 (75P) MMT4321114 Transverter , • £149.60 (n.C.) pli8K2f4M 2 way harness A4 4' 6' .• ir £2.37 (750) MMTI44:28 Transverter • • £38.87 (n.c.) 2M ANTENNAS £1.79 (75p) MMC144T2 or 4 or 28-30 IF cony. • • £20.25 (n.c.) 11 . ir MAX £2carr. C5f2M 5db colin ear .. £4.86 (1.50) MMC144!28 cony. LO.. .. £22.50 (n.c.) any quantity • . 5Y/2M 5 el yogi £6.96 (1.00) £8.42 (1.50) MMC70128-30 1F cony. .. • • £20.25 (n.c.) A10 10'r A1212' xJ BY/2M 8 et yogi £9.10 (1.00) £10.15 (1.50) MMC432/28-30 or 144 cony... £24.75 (n.C.) 10Y:2M 10 el yagl £19.35 (1.50) Brackets etc - MMC1296.28-30 or 144 cony. • . £28.10 (n.c.) PBM10/2M parabeam £23.00 (1.50) full range stocked send SAE for catalogue MMD050 50MHz counter .. £66.96 (n.c.) P131.11412M parabeam £28.35 (135) HF BEA MS MA0050:500 500MHz counter • • £85.32 (n.c.) 5XYi2M 5 el x'd yogi £14.50 (1.25) MMA144 2m pre-amp.. .. £14.62 (n.c.) Hy-gain TH3 MK3 10.20 .. .. £154.00 (3.00) - • 8)(Yr2M 8 el x'd yogi .. £18.10 (1.50) HY-galn TH3 JR 10-20 .. .. £108.00 (3.00) MM0500P Pre-scaler.. • • £27.00 (n.c.) IOXY,r2M 8 el a' d yogi £23.95 (1.75) MMV1296 70-23cm trickier .. £33.75 (n.c.) Mosely TA33 High power 10-20 .. £110.00 (3.00) • . PMFIf2C Circular harness 04,'2M 4 el quad .. SS £14.85 (1.50) HF VERTICALS VHF MONITOR RECEIVERS 0612M 6 el guad £19.80 (1.75) Hy.gain 12 AVO 10-20 • • . £37.68 (1.50) BELCOME AMR104 8 ell's .. . • £106.87 (n.c.) 05:2M 5 el slot £12.35 (1.25) Hy-gain 14 AVO 10-40 .. . £53.43 (1.60) N R56 silo L 11 ch 'a .. £54.00 (7011) 013 2M 8 el slot £16.55 (1.50) Hy-gain 18 AVT/WB 10-80 .. £72.50 (2.00) TM56B 230v/I2v d.c. £165.00 (1.00) £2,40 (15p) SVMK12M vertical sial kit £3-45 (750) ROTATORS )(tale for above .. x'd yuiu .. £8.40 (1.00) CDC AR30 £44.43 (1.25) SHORT WAVE RECEIVERS UGPI2M wound plane £6.95 (1.00) CDC AR40 £51.75 (1.25) Trio R30C 0.5-30m1h . • £184.50 (3.00) HO 2M halo head .. £0.09 (50p) CDC CD44 £106.87 (1.50) Drake SSR-1 05.30mth , £149.50 (100) HM.:2M halo - mast £3.55 (750) COE HAM-2 £145.12 (2.00) Yeesu FRG7 0-5-30mth . £163.00 (3.00) PMH2:2M 2-way harness £6.15 (75p) Stolle 2010 £46.40 (1.25) PHH4,2M 4-way !mines* £14.85 (1.00) Stolle 2030 £.51.18 (1.25) CABLES'& PLUGS 70cm ANTENNAS H.F. MOBILE ANTENNAS 75ohm VHF £0.11m 08/ 70cm 8 el slot .. (1.251 £14.00 G Whip trlbander helical .. £18.11 (1.00) 75ohm UHF £0.15m PBM 18/70cm Parabeam £18.95 (1.50) G Whip mullImoblle £21.37 (1.00) 50ahm UR43 Carriage £0.18m MBM48:70cm Multibeam £19.65 (1.50) LF coils for above whips .. £5.48 (55p) 50ohm UR67 Up to 20ro £0.40m MEIM89,70cm Multibeam £26.30 (1-75) 75ohm twin 200w • 800 £0.081m Resonator whips £2.08 (55P) 12XY/70cm 12 el k'd yogi £27.00 (1.50) Basemounts £2.47 (556) 75ohm twin tKw ' Over 20ro £0.24m PMH2:70cm harness .. £5.30 (750) 3(10 ohrn twin feeder £1.25 £0.09m PMH4/70cm harness .. £11.10 (1.00) VHF MOBILE ANTENNAS 5 core rotator 5.0.22m C8:70cm 8db col ineor 834.55 (1.50) Jaybeam TAS 5:8Ih 2m £11.81 (1.00) 8 core rotator £0.35m 1296MHz ANTENNAS Jaybeam U5 70cm .. £18,90 (1.00) PL259 plug £0,60 (150) Barites 1 way° 2m .. 0I5'1296 Vagi £20.92 (1.00) £3.93 (50p) S0239 chetah; socket £0.50 (150) CHIMNEY KIT Banter 5/81h wave 2m £7.14 (1.00) S0239 back-to-back . 0.55 (I5p) DL lashing lilt (Heavy duty).. £9.58 (1.25) 8antex 5:81h wave 70cm £5.62 (502) BNC UHF .. £0.00 (I5p) W ALL BRACKETS COMPACT HF ANTENNAS a pin mie...... £0.114 (I5p) W6 6' «all bracket .. £2.50 (75o) HO-1 Mini-beam 10.20 . pin socket .. £0.84 (15p) W21 21' wall bracket £9.90 (1.50) C4 vertical 10-20 Reducers for UR43 £0.16 (15p) W24HD 21' wall bracket £14.10 (1.20) LL4OX dlpole 80-40 3 terminal Jock plug .. £0,27 (150)

M AIL ORDER & HEAD OFFICE: HOCKLEY AUDIO, 31 SPA ROAD, HOCKLEY. ESSEX. TEL. 03-704 MIMI (2 Illaea) ALL PRICES INCLUDE VAT CARRIAGE AT COST AG E N TS-G3XTX J.R. Electronics. 11)(1 Cale, Ron' Lane, ROmf ord. Essex. Tel. Romford (071)6) 5E956 Access G300TEIredhurst Electronics. Willowbrook, School Lane, Bunbury. Cheshire. Tel. Sunbury 102211250700 G1.13GRX Eric Simpson, o Dross). Road. Falk1rk. StIdlooshlre. T•1. 0324-24428 Alt & MONDAY TO SATURDAY 9 A.M. TO 5.30 P.M. EARLY CLOSING WEDNESDAY

RADIO COMMUNICATION September 1977 669 SE M P.O. BOX 6, CASTLETO WN, ISLE OF MAN Tel. PORT ERIN (0624) 833714

Did you realise that the conductivity of solder is ten times more than the conductivity of copper ? You will know that it is standard practice to use double sided printed circuit boards in V.H.F. and U.H.F. construction with one side used as an earth plane to provide a high conductivity path between earth points. It Is also standard practice to "tin" printed circuits with a coating of solder. This is done to stop the copper oxidising, to make the soldering easier. It also increases the resistance of earth by about ten times. We discovered this fact some years ago, when production equipment on "tinned" boards didn't meet the performance of prototypes on plain copper boards. That's why all our V.H.F. and U.H.F. equipment is manufactured with an earth plane which is cleaned in an acid bath, washed, dried and finished with a solder through protective coating. It takes longer, but it's just one of the reasons why our equipment has the edge.

NEW! The only one available THE SENTINEL STAN DARD 2 METRE PRE-A MPLIFIER Same circuit as the one above but without the RF switching. SENTINEL TOP BAND CONVERTER Price: £7.75 r VAT - £8.72. IN STOCK.

Top Band (Marine Band) to 20 metre converter. It you miss being THE PA3 able to listen on 160 metres this provides the answer. 1-8MHz- Size only about 1 cubic Inch to fit inside your transceiver. N.F. 2-3MHz In, 14-14.5MHz out. Price £18.00 + VAT = £20.25. IN 2dB gain 18dB. Price: £5.57 VAT - £8.27. IN STOC K. STOCK, SENTINEL H.F. PRE-AMPLIFIER. These are wIdeband pre- 2 METRE CON VERTERS amplifiers from 1-40MHz. N.F. I dB, gain 15dB. Input and output Sentinel D. G. Mosfet converters. These provide a perfor- Impedances 50/75 Ohms. Size: 21" 11" 3'. Price £7.00 mance that cannot be beaten. N.F. 2dB, Gain 30dB. Supply VAT - £7.87. 12V(9-15) 15mA. Size is 21 X1¡'• . 31. IFs: 28-30MHz, 4-6MHz, 2-4MHz. These are also in stock for Marine Band to SENTINEL H.F. PRE-AMPLIFIER with change over relay. 28-30MHz and Satellite Band to 20-22MHz. 4 metres to 28- Same specification as above but including a change over relay 28.7MHz. Price: £18.00 + VAT = £20.25. IN STOCK. for switching straight through. This can be operated by your transceiver for direct connection In your aerial co-ax. Price: SENTINEL 2 METRE CON VERTER £9.00 VAT - £10.12. IN STOC K. Containinea mains power unit and RF gain control. Specifica- SEM "Z" MATCH tion as above. Size: 5' 2" front panel by e deep. Price: £22.00 4 VAT - £24.75. IN STOCK. e compact and attractive A.T.U. 80-10 metres tested at 1kW into 50 ohms. Slow motion calibrated dials. Size only ar 4" SENTINEL 2 METRE CON VERTER KIT IF 28-30MHz. 7r. 50239 and screw terminals for co-ax fed or wire aerials. Performance as above converters. Complete unit with box, Balanced or unbalanced. Price: £28.00 + VAT - £31.50. IN connectors etc. Price: £11.50 + VAT = £12.94. We will get STOCK. them going if you have trouble for £2.50, so you can't go wrong. SEM EUROPAC IN STOCK. Now includes a relay controlled by the ON/OFF switch for 70cms CONVERTERS switching the H.F. equipment between the Europa or your The most economical method of listening on 70cms is our H.F. aerial. I.E. NO PLUG CHANGING. 70cm to 2 metre FET converter. N.F. 3dB, Gain 30dB. Price: • Receive converter-2dB N.F. 30dB gain with MOSFETS. £18.00 + VAT £20.25. Size: 2¡" 11 - 31". IN STOCK. Transmit converter 200MW drive for 200W input. Spurious output-80d81 SENTINEL 70 Size only 9" x 41 front panel, 4" deep. 70cms to 28-30MHz, N.F. 3dB, gain 30dB, Size 2¡' :• 11 Price: £20.00 VAT = £22.50. Price only £100 VAT £112.50. IN STOCK. Complete to plug into Yaesu equipment. PRE-AMPLIFIERS Complete power supply for Europa £45.00 4- VAT - £50.62. IN These must be the most cost-effective items being advertised STOCK. in these pages. EUROPASS All solid state Europa. THE SENTINEL AUTO MATIC 2 METRE PRE-A MP LI FIER • Receive converter 2dB N.F. 30dB gain. Contains an RF operated relay for connecting straight into your ' Transmit converter 200M W input for 10W output, capable of transceiving aerial co-ax. Performance: 1dB N.F., 18dB gain operating into o/c and s/c loads. from selected FETS. Supply 12V nominal. Price: £13.00 + VAT • Front panel meter reads P.A. collector current. = £14.82. B/L sockets standard, S0239s £1.50 VAT £1.69 • Contains rectifier and smoothing circuits for operation off extra. 12V a.c. or d.c. Price: £80.00 + VAT = £90.00.

ALL OU R PR O D U C TS C A R R Y A 12-M O N T H GU A R A N TEE •

To order: C.W.O. or credit card. We take credit card orders from anywhere in the world, just send or phone your card number for same day service. We welcome trade enquiries from anywhere in the world. If you require more detailed information or help do not hesitate to ring or write.

670 RADIO COM MUNICATION September 1977 AMATEUR ELECTRONICS UK MAIN SOLE S PLUS- AGENT W A42 l e !•‘: t ',JAINSC. AGENT E , ELE CTR O NICS YOUR BEST BUY FOR YAESU MUSEN!

/ AS DIRECT IMPORTERS

YAESU W E OFFER \./ YOU ... 1. KEENEST PRICES 2. LARGEST RANGE 3. HIGHEST STOCKS 4. TOP AFTER-SALES SERVICE 5. BEST DEMONSTRATION 111 FACILITIES EX-STOCK DELIVERY ON THE FRG-7 PICTURED ABOVE AS WITH ALL YAESU MAIN ITEMS. NO W'S THE TIME TO BUY— PRICES WILL NEVER BE LO WER! HO W TO REACH US (EASY PRIVATE PARKING ON OUR 70 ft FORECOURT) FROM SOUTH AND EAST. We are located approximately two miles from Junction 5 of the M6 from which follow signposts to Birmingham. Within mile turn right at Clock Garage and proceed towards city. After one mile look for traffic lights at Fox á Goose and immediately over the lights take minor left fork Into Aluni Rock Road. We are located one mile from this point. FROM NORTH. Leave M6 at Junction 6 (Spaghetti) and follow left fork down to traffic island beneath motorway complex. Take third turning off to Lichfleld. One mile further on follow A4040 to the right and within 100 yards vare again to the right, approximately one mile further on brings you to the Fox & Goose. Turn right and see preceding directions. FROM THE WEST AND SOUTH/WEST. Follow M5 then M6 to Spaghetti Junction (see above). Alternatively. leave M5 at Junction 4 or 3 and proceed to inner ring road. Turn South on ring road and leave on A47 (East). We are located three miles from this point.

H O U R S: 9.30-5.30 continuous including Saturdays—Early closing Wednesday 1pm, or, if you can't make it, we will gladly ship by Securicor at no extra cost.

£2.50 for 25 pence! SensationalATLAS-210/215X 25 pence brings the latest Yaesu catalogue with our Credit Voucher for £2.50 against eventual SUPERB TECHNOLOGY FRO M THE purchase. A couple of stamps brings the Atlas U.S.A. £395 !- VAT —EX-STOCK leaflet or our used equipment list.

SU PER SERVICE FRO M YOU R LOCAL M A N! 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, TEL: WISHA W 71382 (EVENINGS: CARLUKE 70914). AGENT: W ALES & WEST—ROSS CLARE, GW3N WS, CAERLEON 422232

508-514 AL U M ROC K RO A D 1497 021-327 BIR MING H A M 8 Telex337045 6313

RADIO COM MUNICATION September 1977 671 MODULAR ELECTRONICS PROPRIETOR: P. J. CRAIG, G8CQS 95, HIGH STREET, SELSEY, NR CHICHESTER, WEST SUSSEX. P0200QL. Telephone: Selsey (024-361) 2916.

SOLE DISTRIBUTOR TO THE AMATEUR RADIO 1615139 WIRE END VARAC TOR. 7p1(4V) 5w Input HIGH QUALITY FINISHED UNITS MARKET FOR THE PRODUCTS OF SOLID STATE suitable for Mull service. Only 55p I 8%. Transverter M.E.T. 432-28-10 compatible with the FT101 SCIENTIFIC INC, Dual Mixer VHFrUHF FETO Type E420 (dual E300) or slnlilitr. Full 10.v output with low Intormodulation MANUFACTURER OF R.F. PO WER TRANSISTORS Ideal for mixers. Products £72. VAT 12 .5%. Treneverter M.E.T. USING ADVANCED ALUMINIU M NICHROME With data only £1.00 + marked WD383 (Pye) 432-50-10 an above but with 50MHz IF [74 - VAT. Both METALLISATION FOR RUGGED RELIABLE UHF Antenna Changeover Relays. Magnetic *bow, have better N.F. than 2.7d13 with 28d13 RX Oslo. OPERATION Devices 951-170-12V 50 ohm good VS WR to 1296MHz. M.E. FM15-1, Better than 13w. out when driven wlth the 2200,3 or stroller 1w FM equipment. £35 +. VAT. ALL PRICES EXCLUDE VAT AT 8% Direct cable entry for RG43 or similar cable. Price [5.75+ VAT e% M.E. FM15-2. Better then 14w out when driven with the 2200GX or similar 2w FM equipment. [35 F VAT. Type Specification Frequency Price Heidelnks suitable for Transistor amplifiers. Single M.E.L. 202 ,25 Typ 25w dean SSB Iron, the ICON IC202 2144427 1w 10dB 12.5V 175MHz £0.54 sided types. REDPOINT TYPES. Prices Reduced. VAT fully automatic changeover. Also suitable for the ICOM 21432168 tw 1011B 28V 175MHz £9.78 at 8% IC215 on FM [37+ VAT. 2145913 2vo 748 12-5V 470MHz £1.40 4Y1 4.5 deg. C per W 2.36 wilt, mounting area 2143553 2.5w 948 28V 175MHz £7.95 1-26 - £0.70. M.E.L. 40. 40w Linear amplifier. Made to your drive level 2N8080 4w 12d5 12.5V 17SMHz £3.90 6M1 2.6 deg. C per W 5 a3'85' with mounting ores Of frorn9 to 13w. You specify thedrivelevel. £40 + VAT. $01143 10w 1001 12.5V 220MHz £5.56 1.3r £1.10 M.E.L. U4 300Mw for lull 4w Output ni 432MHz• No 2145081 15w 6-adB 12.5V 175MHz £.5.32 DAU 4.5 deg. C per W 52 , 12Ornm £0.55. Switching. BNC connectors 8.24+ VAT. Duo to weight, postage is 25p 011 EACH Heatsink. No 2148062 25w 6.2dB 12.5V 175MHz £730 M.E.L. U10 2.5w tor full 10w output at 432MHz. No other goods under this postage [beige. 2148033 30w 5.7dB 12.5V 175MHz £8.40 switching. BNC. 829+ VAT. 2148084 40w 4.5dB 12.5V 175MHz £11.10 Components. VAT at 12.5% unless marked otherwise. RF2127 70w 8.6e1E1 12.5V 175MHz £23.60 DAM Superior Quality PTFE Film Trim mers, PREA MPLIFIERS FOR 144 AND 432MHz Ornrn I-5-901-113p. 2/45944 2w 9dB 12.5V 470MHz £8.22 PA1. 50 ohm In and out. Uses latest 3N204 device. Type 7mm 2-0-180-18p. 2145805 4W 8d8 12.5V 470MHz £7.51 N.F. 2d8 paln at 18 to 217dB. tj square fits most gear. 10mm 3.5.850-151, 2145045 10w 648 12.5V 470MHz £.9.46 Only E5.50 VAT. 501136 10w 5-508 12.5V 470MHz £0.10 Mullard Trnin 1-60-1519. PA.U1 for 432MHz. Gain 11dB N.F. 2.4dB. 55mm. S01083 25w 6-8dB 12.5V 470MHz £16.45 Surplus lOrnm 2.5-250-4P. square. £6.50 VAT. The Ul has been parametered S01089 40w 4.3d8 12.5V 470MHz £19.47 Mica Compression Trim mers. Very suitable for the lot compromise N.F. and has Improved Interned 2145550 10ve 52d8 13.5V 175MHz £4.60 Collector tuned circuit of Power amplifiers. performance. Une the U2 lor min N.F. bul be warned It 2145591 25w 4.4d8 13-6V 175MHz £5.50 Ciydon. 10.60pt-15p. Handles 50w. has poorer Interrnod perlormence. 2N5179Gen. purpose amp. F.T.- 90014Hz 1072 £9.72 Radlospares. 4.4001-200. Handles 70w. 2145031 UHF amp. N.F.- 2.508 at450MHz 1072 £2.13 PA.U2. Gain 12dB N.F. 2dB. The best low noise RADIO FREQUENCY CHOKES pertormance. Uses the TRW TP491. Only [7.54)+VAT. TR W. Very Low Noise. 3GFiz F.T. "T" Pack (Pin 12 uH, 0.22 pH. 0.33 pH. 0.68 uFf. 33 H. 20 PH, Both of the UHF preamplifiers can be supplied, boxed layout same as BER93,81) Interchangeable impioved 1000 pH. All at 12p+ VAT. and tuned with BNC connectori for additional £4.80. low cost repineernents for same in most circuits. FERRITES. Only genuine Mulford with correct As supplied lo Ihe Ministry. (470MHz aopficalions). characteristics. VAT 8% TP390 2.7dB N.F. at 450MHz £1.9) FX1115 singte hole Op. FX1898 6 hole 10p. FX2049 NE W! RF PO WER MODULES. Complete tuned and TP393 2.0dB N.F. at 5COMHz £2.00 double aperture transformer coro tie - 200 lop. tested, ready to install in your home•made rig. Low TP491 1.6dB N.F. at 500MHz £2.10 cost unite. 92 55rom Tuned to 50 ohm in/out. PLUGS AN D SOCKETS by COLINE. VAT at 8% MULLARD. 5GHz F.T. "T" Pack for 12.36MHz PM2-10 lop out 13.5dB gain only 400m W drive £15+ BFR90 3.2dB N.F. at 1250MHz £3.50 BNC single hole Socket 500. BERGH 2-5dB N.F. at /250MHz £4.00 81-SC 50 ohm Plug UR43 typo 5Sp. VAT. (12 .,,,I) Amphenol UHF Socket 4 hole fixing S0239 Silver Plate PM2-1515w out 10.5.113 gain only 1.3w drive 8164- VAT. NE W 41Ip. P1442-25 25w oul 8.5dB gale only 3.5v+ drive [17.504- The very latest FANTASTIC PERFORMANCE "D" VA T. (12)%) NOS DUAL GATE MOSFETS. UNBELIEVABLE '14' Plugs RG43 cable. 501, The above tiro for 144MHz use with 13.8V zupply. INTERMOD AND CROSS MOD PERFORMANCE INTEGRATED CIRCUITS VAT 8% p7,470.4 4m ou t lode. polo only 400m w &Iva £16.75 WITH TYPICAL NOISE FIGURES AT 144MHz OF MOTOROLA MC12013 Presenter with MTTL output. VAT. (124 j,',) 1• 5dB. Not a misprint 1-5dB SIGNETICS S0306 Divides by 10 or 11 typical toggle frequency 600MHz. PM70-10 I0w out 5.703 gain only 2.7w drive £16.75 • with data only f.2.00 0'/VAT. 51/ Supply. Easy to uso with datacopy. £10.50. VAT. 024 SURPLUS RF PO WER. Small quantities only. NEW, PRESCALER KIT. PCB MC12013 all components PM70-100 10w out 840 0010 only 1.6w drive £17.75 , Chock availability before ordering. to build cemotete with 2 stage input amplifier using VAT. 02; PT2125E 4V, In for 154v out at 144MHz 13.8V £2.80 VAT 3GHz "T" pack transistors. All components excluding STRIPLINE STU D RF CATV TRANSISTOR. box. Sensitivity typ. 30Mv at 432. £18 + VAT 8% The above are for 432MHz uso with 13.8V supply. Sim 2N5947. 5W Digs. FT 1.2GHz at 75mn. Hiyl, oain. AISO available as a tested board (unboxed) at [20 4 4% Specials can be made for 3134MHz for use as iniection Only 800 + 8%. In-house coded. M OTOROLA MC14961.. Uses: Multiplier, Bal Mode. source tor 1296MHz equipment. VARACTOR BOLT TYPE ITT VBC7SA later. Phase Del. etc. With Datacopy. £1.75 VAT 8% 6m In el 384MHz more then 2.5w out al 1,152MHz Only N OS SCL4001AE 18p VAT 8% NE W! Complete boxed tested PRESCALER. F..3.04) -r 8% CERA MIC CAPACITORS. VAT 12.5% Input requirement only Typ 30mV. Boxed with BNC HP5082-3080 UHF pin diodes. 659 + VAT (BM ;Neut. 5V supply. Adequate output to drive any Disc Erie type 100001-2.5p. Disc Erie type 2000 - 2.51s- 2N4-429 lin out at 1GHZ 28v only £1.00 - 8% 50MHz counter. Divides by 10 up to min 500M114 Top. Feedthrough Solder in typo: 1009p1 Erie-tip. 5001 Erie'-. Small Signal Transistors and MOSFETS, 600MHz. and you 'Joni ham to feed the rig In to pet a 7p. 406 73-6 51, 40341-60P. 35204 Third Generation ot,t uteutont. Only £26 VAT at 8% MOSFET-E1.20. BF528-900. 2N2369-15p. BC107- SPERRY BECK MAN .55' Dispinys. Sel 01 4 digit* 12p, pints-30p. BFX69-909. + (-1 and three seven segment numerals. Only £2.00 CONVERTERS Br/90[1.03. BC149 8P(12.5%)• CIL108 8P(I2.5%) , VAT 8% MEC432.28 and MEC 432-i44 NE -'.2.5dB. £21 - VAT POSTAGE: SMALL COMPONENTS 25p. HEATSINKS SEE LIST. PREA MPLIFIERS 40p. LINEARS/TRANSVERTERS 90p. MINIMUM ORDER: £1.50 U.K. VAT FREE EXPORT MINIMUM £15

CO MING SOUTH? VISIT OUR SELSEY SHOP. LARGE DISPLAY DIGITAL W ATCHES, RADIOS AND CASSETTES. COMPONENT ROOM AT REAR FOR ALL ADVERTISED ITEMS, PLUS MORE GOO DIES.

PLEASE NOTE: CLOSED ON MONDAYS DURING THE RALLY SEAS ON. ALS O CLOSED DURING MAJOR CONVENTIONS BARCLAYCARD BARCLAYCARD OR ACCESS OVER £10

672 RADIO COMMUNICATION September 1977 AMATEUR RADIO EQUIPMENT WITH PROFESSIONAL PERFORMANCE

FOR 144 MHz QUALITY PERFORMANCE .1 • THE TOP TRANSVERTER FROM THE PEOPLE WHO KNO W! MMT144/28 - 28 MHz TO 144 MHz 10 WATT TRANSVERTER

As you may already know, we are now manufacturing 14.1MHz all.modesolid.state linear trans. verter, MMT144/28, as pictured here. This 144MHz unit is fully compatible with any 28MHz drive source and provides 10 waits Continuous power output from power transistors capable of withstanding severe mismatch. An Internal aerial changeoverrelay of the PIN diode type Is incorporated which has a through- loss of less than 0.2d8. The combination of a low distortion balanced transmit mixer incorporating protected dual gate MOSFETS, to produce a spurious.free linear signal and a low noise receive converter, makes the unit ideal for all merles of transmission at 144MHz, particularly where a high degree of stability, linearity and sensitivity are of prime importance. The use of high O circuitry throughout ensures an extremely good spurious rejection end selectivity. The unit lu housed In a highly durable black diecast case, and all circuitry is constructed on high quality glass-fibre printed circuit board. The high power linear amplifier stapes are housed In a separate internal compartment, thus ensuring excellent electrical and thermal stability. If you have an HF Bands rig and you're thinking of moving on to 2 metres. the MMT144/28 must be the transverter for YOU.

SPECIFICATION Current consumption: 2-2 Amps peak Receiver converter noise figure: Better than 2.5dEt Power output: 10 welts continuous rating Frequency range: 144-146MHz Power connector: 5.pin DIN Drive requirements at 28MHz: 500m W or 5mW Input modes: S W FM. AM or CW RF Inputfoutput connectors: 50ohm BNC Relative 116MHz output: —65dB Input frequency range: 28-30MHz Sine: 187 120 x 53mm Other spurious outputs: —65d8 DC power requirements: 12 volts nominal Weight: 800g Receiver converter gain: 30dilt

500 MHz DIGITAL

FREQUENCY METER MMD050/500

GENERAL DESCRIPTION: Recent advances In MOS technology have made possible the development el this extremely compact frequency meter which far the first time offers the UM' a convenient cost-elective means of frequency measurement. A close tolerance quartz crystal in the 5MHz range together with CMOS binary divider Integrated circuits generate the accurate 400ms gating period for the main counter MOS LSI circuitry. Thls 1St circuity drives a multiplered 6-digit LED display through current amplifiers. This display is led from an internal store which is constantly updated from the main counter register and thus the display lo continuous and flicker-free fore constant frequency reading. The display uses the latest high efficiency red LEDs with a digit height of lOmm and overall display width of 45mm. SPECIFICATION: The counter has two ranger: which are selected by supplying +12 volts to one of two pins on the DIN seckeL internai diode switching brings the input in the 0.45.50MHz range to a wide. Digit Height: lOmm Display Width: 45mm band amplifier which drives a high speed ILL divider In the main counter logic. On the Case Sloe: Ill s. 80 a 27mm 50.500MHz range the diodes switch in a high speed ECL presenter and the decimal point Is changed accordingly. Frequency Ranges: 0•45-50MHr; 50-500MHz A low angle AT cut quartz crystal 1$ used giving a typical temperature stability of 0.5ppm per Sensitivity: Better then 50mV RMS over 0-45-50MHz degree C. Provision is made far getting the crystal frequency, and the accuracy of reading is Bettor than 200mV RMS 50-500MHz normally better than 200Hz at 50MHz, or 2kHz to 500MHz. The counter has reverse polarity protection and operates satislactorily from a nominal 12V dc Input Connector: 50ohm BNC Input Impedance: 50ohm supply. A suitable 5-pin DIN plug is supplied. Power Connector: 5-pin 270 locking DIN socket Power Requirements: 11-15 volts dc at 300mA approximately PRICE: £85.32 inc. VAT

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. Incidentally all ol our products are FULLY GUARANTEED FOR 12 MONTHS

MICRO WAVE MODULES LIMITED BROOKFIELD DRIVE, AINTREE, LIVERPOOL L9 7AN TELEPHONE: 051-523 4011. TELEX: 628608 MICRO G

RADIO COMMUNICATION September 1977 673 COM MUNICATIONS \e/ RECEIVER BY YAESU YeC Model FRG-7

FR G••7 M a . • I 1.1 L.e.1 NU E S U M U 1151.1 S. - U .

UNPRECEDENTED SENSITIVITY, SELECTIVITY, AND STABILITY DIAL CALIBRATIO N 0.5 kHz TO 29.9 MHz COVERAGE WITH O UT GAPS

WILL OPERATE ON DRY CELLS (12v. DC) OR 100-234 VOLTS AC.

YAESU MUSEN CO., LTD.

For further details, contact OUR AGENTS :

Amateur Electronics, South Midlands Communications Ltd. Western Electronics (UK) Ltd., 508-514 Alum Rock Road S.M. House, Osborne Road, Fairfield Estate, Alum Rock, Totton, Near Southampton, Louth, Birmingham 88 3HX Hampshire SO4 4DN Lincolnshire LN11 OJH

674 RADIO COMMUNICATION September 1977 London's Amateur Radio Radio Shack Ltd Stockist

CO M MUNICATIONS DRAKE RECEIVER

e BUILT-IN TELESCOPIC ANTENN A 0 SYNTHESIZED e GENERAL COVER AGE • LOW COST e ALL SOLID STATE e BUILT-IN AC PO WER SUPPLY e SELECTABLE SIDEBANDS e EXCELLENT PERFOR M ANCE TRIED AND TESTED WITH MANY THOUSANDS ALREADY IN USE.

£149.85 inc. V.A.T. (Free Securicor Delivery)

I-F Rejection: Greater than 50dB (til fd below 20MHz. Image Rejection : Greater than SOdB Greater than 40dB fd above 20MHz.

Audio Output Provisions: ilntaet ierdnia.laSbohsmspsePaekaekrhetwoner, dppulio; geolcilsn on front panel Antenna: Self contained telescopic whip antenna. External h connection to terminal striP.(75 ohm Input impedance unbalanced.) Muting Provisions: External mute jack (RC A typo) that provides normal Frequency Coverage: 0.5 to 30MHz in 30 ranges each tunable over 1MHz reception with closed circuit and mute with open range with a dial having 10kHz graduations. circuit connection,.

Reception Modos: C‘v. USB, LS13. AM. Power Supply: o typo "D" (1.5V) dry cell battetlea (not included). Tapped transformer 10 movido operation from 11TV Sensitivity: At least 10dB Si- N/N under the following conditions: -± 15% or 240V ± 10%-20%, 50-50 Ha source with Mode Frequency Input Level automatic switch over to batteries when ac lino la SSS 0 5.2MHz 1.0uV disconnected. 2-30MHz 0.3uV AM 0.5-2MHz 3.0uV Current Consumption: Less than 100mA quiescent at 12 V-dc. 2-30MHz 1.0uV (AM: 1000Hz 30% modulation.) Dial Lights: Momentary push button to light when on W W1' Output: Capable el 200in W output on ssb at 2MHz with input operation. Always on for ac operation. signal of 0.5,uV and 2 watis output with 5t1V Input. Clarinet : Tunes minimum of ± 2kHz and maximum of ± 5kHz. Audio Distortion: Less than 5% @, 2 watts

Calibration Accuracy: Within SkHz at all Irequencles. Size: 5.5H 13 W x 11'D (14 x 33 Y 28 cm).

Selectivity BAND WIDTH Weight: 14 lbs. (6'4 kg) Mode 6dB SSS 3kliz ± 25% •These voltages are j the open circuit signal generator voltage, Le., the voltage AM 55kHz -± 25% on the meter ol a HP Model 606 Generator.

S.A.E. WITH ENQUIRIES PLEASE ACCESSORIES AVAILABLE:

Drake HS-1 Headphones RADIO SHACK LTD. W orld Radio Si TV Handbook

188 BROA DHUR ST GARDENS, LOND ON N W6 3AY Just around the corner from West Hampstead Underground Station Access Telephone: 01-624 7174. Cables: Radio Shack, London NW6 Telex 23718 Radac KG. Giro Account No: 588 7151 Open Mon-Fri 9-5, Sat 9-12.30. Closed for lunch 1-2

RADIO COM MUNICATION September 1977 675 C O U N CIL RADIO SOCIETY OF GREAT BRITAIN President Lord Wallace of Coslany 35 Doughty Street, London WC1N 2AE Executive Vice-President Telephone 01-837 8688 D. S. Evans, G3RPE, PhD, BSc, MIM Immediate Past-President Founded 1913 Member society, International E. J. Aliaway, MB, ChB, MRCS, LRCP, Incorporated 1926 Amateur Radio Union G3FKM Honorary Treasurer J. O. Brown, LLB, FCA, G3DVV PA TR O N: H R H The Prince Philip, Duke of Edinburgh, KG Telecom munications Liaison Officer R. F. Stevens, G2BVN The national society representing all UK radio amateurs Ordinary members P. BalestrIni, TEng(CIE), MITE, G3BPT J. Baziey, G3HCT Membership is open to all those with an active interest In radio experimentation end C. H. Parsons, GW8NP com munication as a hobby. Applications for membership should be made to the general D. M. Pratt, BTech, MIEE, MIERE, G3KEP manager, from whom full details of Society services may also be obtained R. F. Stevens, G2BVN G. M. C. Stone, G3FZL C. J. Thomas, G3PSM GENER AL MAN AGER AN D SECRETARY EDITOR Zonal members Zone A. B. O'Brien, G2AMV G R. Jessop, CEng, MIERE, G6JP A. W. Hutchinson Zone B. J. Anthony, G3KQF Zone C. D. J. Andrews, G3MXJ Zone D. W. A. Scarr, G2WS, MA, FBIS Zone E. D. M. Thomas, GW3R WX Zone F. W. F. McGonigle, GI3GXP A N NU AL SU B S C RIP TIO N R A TES Zone G. A. M. Allan, GM3ZBE UK corporate: £8, including VAT Overseas: £8.

REGIONAL REPRESENTATIVES Associates under 18: £3. Students aged 18 to 21: £4.50. Region 1—W. M. Furness, G3SMM Region 2—R. C. Andreang, G4CMT OAPs with 15 years' me mbership: £4,50. Affiliated societies: £6.50(including Region 3—H. S. Pinchin, G3VPE Region 4—T. Darn, G3FGY Radio Communication): £3.25 (excluding Radio Communication), Region 5—P. F. ChIlcott, G4BBA Region 6—F. S. G. Rose, G2DRT Region 7—N. A. Smith, G3HFO Region 8—D. N. T. Williams, G3MDO Region 9—H. W. Leonard, G4UZ Region 10—R. G. Barrett, GW8HEZ COMPOSITION OF RSGB ZONES Region 11—P. H. Hudson, GW3IEQ Region 12—F. Hall, GMBBZX Zone A: Regions 1, 2 and 18 Zone E: Regions 10 and 11 Region 13—A. B. Givens, GM3YOR Zone F: Region 15 Region 14—(Post vacant) Zone B: Regions 3, 4 and 5 Region 15—H. J. Campbell, GI8FOK Zone C: Regions 7, 8, 16 and 19 Zone G: Regions 12, 13 and 14 Region 16—R. E. G. Kendall, G8BNE Zone D: Regions 6, 9, 17 and 20 Region 17—L. Hawkyard, G5HD Region 18—P. J. Fay, G3AKG Region 19—D. S. Smith, G4DAX COMPOSITION OF RSGB REGIONS Region 20—G. Mather, G3GKA Region 1 Cheshire, Cumbria, Greater Manchester, Isle of Man, Lancashire, Merseyside. HO NORARY OFFICERS Region 2 All that oart of Humberside north of River Humber, North Yorkshire, Awards managers South Yorkshire, West Yorkshire. hf—C. R. Emery, G5GH Region 3 Hereford and Worcester, Salop, Staffordshire, Warwickshire, Weet vhf—Jack Hum, G5UM Midlands. Region 4 Derbyshire, all that part of Humberside south of River Humber, Emergency com munications manager Leicestershire, Lincolnshire, Nottinghamshire. P. BalestrInl, G3BPT Region 5 Bedfordshire, Cambridgeshire, Northamptonshire. Intruder Watch organizer Region 6 Berkshire, Buckinghamshire, Oxfordshire. S. A. G. Cook, G5X13 Region 7 Greater London south of River Thames, Surrey including that part of London north of the Thames administered by Surrey. Microwaves manager Region 8 Kent. East Sussex, West Sussex. D. S. Evans, G3RPE Region 9 Cornwall, Devon. QSL Bureau manager Region 10 Dyfed, Gwent, Mid Glamorgan. Powys, South Glamorgan, West A. O. Milne. G2MI Glamorgan. Region 11 Clwyd, Gwynedd, Slow morse organizer Region 12 Grampian, Highland, Island Authorities, Tayside. M. A. C. MacBrayne, G3KGU Region 13 Borders, Fife, Lothian. Taped lecture library curator Region 14 Central, Dumfries and Galloway, Strathclyde. S. W. Coursey, G3JJC Region 15 Northern Ireland. Trophies manager Region 16 Essex, Norfolk, Suffolk. P. A. Mlles, G3KDB Region 17 Isle of Wight, Channel Islands, Dorset, Hampshire, Wiltshire. Region 18 Cleveland, Durham, Northumberland, Tyne and Wear. VHF manager: D. A. Evans, G3OUF Region 19 Greater London north of River Thames, Hertfordshire. Region 20 Avon, Gloucester, Somerset. Correspondence to RRs and honorary officers should be addressed directly to them (OTHR).

RADIO COM MUNICATION September 1977 676 CURRENT COMMENT Following the letter received from the Home Office, and "RADIO reproduced on page 594 of the August issue, the various aspects of the matter have been considered by the VHF Committee, COM MUNICATION" the Repeater Working Group and the Telecommunications Liaison Committee. CHANGE OF ADDRESS A meeting with the Home Office has taken place and we are now awaiting the reaction of the administration to the proposals made by the RSGB. Since 1 August the Radio Communkailon editorial office has been transferred to Chelmsford, and all contributions, Members' Ads, and correspondence concerning the CONTENT of the journal should now be addressed to: The Editor, • Radio Society of Great Britain, QTC 88 Broomfield Road, Chelmsford, Essex CM11SS.

amateur radio news It is stressed that all other RSGB matters, INCLUD- ING "RADIO COMMUNICATION" DISTRIBU- TION, and subscriptions, will continue to be dealt GB2RS with at RSGB headquarters. Editorial material ad- At its last meeting Council approved the suggestion of the dressed to headquarters and non-editorial matters Membership & Representation Committee that an ad hoc sent to the new editorial office will result In un- necessary delay and expense. committee be formed to investigate thoroughly the matter of the Society's news broadcasts. It is intended to consider the following aspects: geographical coverage, frequencies, modes, times and contents. It would be appreciated if members, or indeed any listeners Netherlands licences to the service, who have thoughts on the subject or have A new callsign allocation system for foreign amateurs has suggestions to make, would send their comments to: Mr B. O'Brien, G2A MV, "Tanglewood", Anthony's Way, Hes- been introduced in the Netherlands. The use of the PA9 wall, Wirral, Merseyside, L60 OBP. prefix is discontinued and the callsign will consist of the Observations from news-readers are particularly sought. visitor's home callsign followed by /PA or ;PE depending All views will be carefully considered by the committee, on the class of the original licence. Applicants for a tempor- ary Netherlands licence must send a copy of the original whose final recommendations will be placed before Council in due course. It is hoped to publish details in Radio Corn- home country licence verified by the applicants' administra- nualication but no date is given for this as the committee tion and also a copy of the official information concerning wishes to have time to make a thorough job of the exercise. the terms of the licence in the country of origin. Applica- tions must be made on a special questionnaire and accom- Aerial and mast planning problems panied by a remittance of D.FI.50 which secures a one-year licence. At least two months notice is required. Copies of the These problems abound among our members and assistance questionnaire and other information concerning the new is urgently required from those members who are both willing arrangements may be obtained by sending a 8fr by 4in sase and qualified to give advice. to RSGB HQ. It would be appreciated if any members who are solicitors At a time when efforts are being made to ease the formali- or otherwise qualified, and who possess some experience of ties necessary to obtain reciprocal licences, the new require- planning procedures, would offer their services to the RSGB ments of the Netherlands administration seem to be a back- by initially contacting Mr R. W. Price, G4BSO, 31 Broomy ward step. Hill, Hereford, HR4 OU, who is a corresponding member of the Telecommunications Liaison Committee with special responsibility for planning. Slow scan television convention The intention and hope is that a number of members in The British Amateur Television Club is organizing a slow different areas of the country will become available to give scan television convention, to be held at the University of initial advice to members as to the best method of dealing Aston, Birmingham, on Saturday 19 November 1977 from with their particular problems. 10am to 5.30pm G4BSO will be very happy to give further information to It is hoped that many amateurs will bring pieces of equip- any members who think they may be able to assist. ment to exhibit and demonstrate. All known suppliers of commercial sstv equipment have been invited to exhibit. North Bedfordshire VHF Group Lectures are being organized for the afternoon. This group has been formed to stimulate the building of Non-club members welcome. Admission charge 50p. For equipment for the vhf/uhf bands in north Bedfordshire. The further details and maps of the area send stamp for return secretary is Mr M. Dannatt, G8MCY, 83 Sandy Road, postage to: Mike Crampton, G8DLX, 16 Percival Road, Potton, Beds SG19 2QQ. Rugby, Warwickshire CV22 5JS.

RADIO COMMUNICATION September 1977 677 Scottish Amateur Radio Convention Welsh Amateur Radio Convention Adam Smith Centre, Kirkcaldy Oakdale Com munity College, Oakdale, 10 September 1977 Blackwood, Gwent 10am-6pm, 25 September 1977 Exhibition and trade stands: gam-6pm Convention: 1pm-5.30pm Trade exhibition Exhibition station Dinner: 7.30pm Exhibition of early radio equipment Admission: Convention and Exhibition, £1 payable at TV and rtty display RSGB bookstall door. Convention, Exhibition and Dinner, £4.50, obtainable only in advance from LECTURES Andrew Givens, GM3YOR, 41 Veronica "A visit to the Seychelle Islands", by R. Brown, G3LQP/ Crescent, Kirkaldy, Fife KY1 2LH. VQ9RB. "The launching and post-launch control systems Facilities for the disabled. Bar open throughout the day for Ariel 5. one of the UK satellites", by J. Wright, G3VPW, of the Appleton Laboratory. "Layman's guide to amateur The centre is situated close to Kirkcaldy railway station, radio" (BBC Wales film). which Is on the main Aberdeen—London railway line, and on one of the main roads through the town quite close to Increased parking space this year. Talk-In from 9am, GW3WTZiA on S22 and GB3BC/R6. the main shopping centre. Overnight accommodation details from R. B. Davies, GW3KYA, 16 Vancouver Drive, Penmain. Blackwood, Gwent NP2 OUQ, tel 225825. Third old-timers 3-5 and 7MHz activity event Admission: 50p at the door Contacts between British and Dutch old-timers will be renewed during the period 3-5 October 1977 inclusive of the annual event arranged by RAOTA and the OTC of the would appreciate contacts from radio amateurs or swis Netherlands. Activity periods will be (a) 0900-1130gmt, who worked or who are now resident in the East Anglian (b) 1330-1530gtnt, (c) 1730-1930gmt. area. This is the area bounded by lines from north London Working frequencies, and the times that co-ordination and to Rugby and the Wash. Those wishing to give information information stations will be available each day, are: or assistance should seek further information from either of 3-5MHz telephony, Periods (a), (b) and (c): 3,605-3,695kHz the following: Mr P. J. Wright, G3SEM, cio BBC (East), with co-ord/info on 3,600kHz from G2PT or G2NR and St Catherines Close, All Saints Green, Norwich NR1 2ND, PAODK or PAOYZ. or Mr A. Othen, G8FSZ, RSGB HQ. 3.5MHz ew. Periods (a) and (c): 3,550-3,570kHz. Co-ord info on 3,550kHz from G2PT or PAOPN or PAOZQ. Put pen to paper 7MHz telephony and 7MHz ew. Period (b) only: 7,075- Ideas for new books on subjects of amateur interest are 7,095kHz and 7,025-7,035kHz. Co-ordfinfo on 7,075kHz always welcome and should be sent to: The Book Editor, (ssb) or 7,025kHz (ew) from G2RQ or PAOPN. Radio Society of Great Britain, 35 Doughty Street, London Participants (all welcome) are asked to call first on the WCIN 2AE. appropriate co-ord /info frequency and then QSY up for All that is required in the first instance is a short descrip- contacts within the bands given above. tion of the book (approximately 200 words) and a suggested

UK FM Group Legal Fund At a joint committee meeting of the UK FM Group (London) The Cardiff RSGB Group and UK FM Group (Southern) which was held recently, it present their was decided that a joint legal fund should be set up in order to have funds available with which to take legal action to JUBILEE CABARET stop jamming and interference to repeaters. The fund has 7.30pm for 8pm, 17 October been set up jointly by the two groups and will be administered by four trustees, two from the committee of each Roath Conservative Club, Cyril Crescent, group. Cheques should be made payable to "UK FM Roath, Cardiff Group Legal Fund" and can be sent directly to: Barclays Members and their guests will enjoy: Bank, 17 High Street, Frimley, Surrey. Alternatively, donations can be handed to the treasurer or Ragchew Chicken and chip supper any committee member of either the London or Southern CABARET (including BBC artists) FM Group. A record will be kept of all donations (which Treban may be made anonymously if desired) and all monies will be Dave Burns returned if the fund is wound-up, otherwise the fund will be Bernard and John disposed of at the discretion of the trustees. Guest comedian Dancing Wartime activities (RSGB publications will also be available) The BBC at Norwich is researching a television programme Tickets £2 each (including raffle), from Cardiff RSGB on the wartime (1914 to 1945) activities of radio amateurs Secretary, M. Fereday, 9 Mill Race Close, Lisvane, Cardiff who were involved in intercept or surveillance duties, and

678 RADIO COMMUNICATION September 1977 contents list. Each proposal will be carefully evaluated and the book editor will be pleased to give prospective authors NE W BOOKS FRO M RSGB any further advice or assistance required. OSCAR- --Amateur Radio Satellites Hilomast Ltd by Stratis Caramanolis Clarbrook Engineering Ltd have transferred their tower Already a best-seller in its original German edition, and mast building business to a new factory at Maldon, with over 7,000 copies sold, the first-ever book on Essex, where in future the company will be known as amateur radio satellites has now been translated into Hilomast Ltd, reflecting the considerable interest in this English and up-dated for this edition. product. The full address is Hilomast Ltd, The Street, The first half of the book discusses the background Heybridge, Maldon, Essex, CM9 7ND. Tel Maldon (0621) to the subject, including orbital geometry, satellite 56480. anatomy, communication principles and telemetry, in some detail. Only after the reader has a clear understanding of the basic principles of communication satellites does the book go on to describe satellites of the Oscar series and how they can be used for communication and experimentation, including QRP RSGB BOOKS tests and sstv. Various methods of plotting Oscar orbits are discussed and the reader is shown how to interpret published orbital data. Although the treatment of the subject matterthrough- out the book is essentially non-mathematical, relevant Whatever are they talking about ? equations and worked examples are given where desirable, and the text is amply illustrated with many "Without a doubt, this is the standard textbook on diagrams, charts and photographs. the subject and anyone with only the slightest interest Chapter titles are as follows: Planets and their in vhffuhf operation should have a copy on his book- orbits; Satellites and their orbits; Anatomy of a shelf." satellite; Satellites as relay stations; Fundamentals Radio ZS of telecommunication via satellites; Telemetry "No serious vhf-er should be without this book. The systems; Satellites of the Oscar series; Operating reviewer's copy is always kept close at hand." With amateur satellites; Learning with AMSAT- C)ST Oscar satellites. 192 pages £3.80 40p p&p The RSGB VHFRJHF Manual of course! Got your copy yet? Radio Amateurs' Examination

404 -{- xii pages Third edition £6.65 inc p & p Questions and Answers Compiled by the RSGB Education Com mittee This book is a collection of model answers to typical Radio Data Reference Book Radio Amateurs' Examination questions, and should prove invaluable to candidates as a revision aid. It (4th edition) demonstrates that adequate answers to such questions need not be "long winded", and will assist the by T. G. Giles, G4CDY, and G. R. Jessop, G6JP candidate in developing a concise answering style It is a sad fact of life that the more textbooks one has, the which could save valuable examination time. longer it seems to take to dig the odd fact out of them, The book is arranged in the same format as the whether one wants to know the input resistance of a examination, with chapter titles as follows: Ele- common-emitter stage, the attenuation of UR77 cable, or mentary electricity and magnetism; Elementary just the BBC1 channel number of the Llanddona uhf tv alternating current theory; Thermionic valves and transmitted Then again, one might be left struggling through a pile of dusty volumes trying to find the melting semiconductors; Radio receivers; Low-power trans- and freezing points of soft solder, the transconductance mitters; Propagation; Aerials; Measurements. equation of a fet, or the clearance size of an MS screw. 120 pages £1.70 -1- 30p p&p Phewl As you have probably guessed, all these little gems are in this new edition of the Radio Data Reference Book, and much more. As before, the aim of the book is to present a wide range of essential reference data In convenient form without The "Radio Communication needless repetition of basic theory. Handbook" costs the earth! The text has been completely revised and a good deal of new material added, including sections on transistors, Actually, we must confess that it is "dirt" cheap when heatsinks and modern filter design. For greater ease of one considers the amount of information packed into reference it has also been rearranged into nine subject its 816 large-format pages. For less than the price of a areas, as follows: Units and symbols; Basic calculations; simple station accessory one gets a superb reference Resonant circuits and filters; Circuit design; Aerials and transmission lines; Radio and tv services; Maps and library in two handy volumes, created by radio meteorological data; Materials and engineering data; amateurs to help you get the best out of your hobby. Mathematical tables. Happy digging I 190 , x pages £3.00 plus 65p p&p Volume 1 464 -1- xvi pages £9.36 inc p&p Volume 2 324 -1- xii pages £8.12 inc p&p

RADIO COMMUNICATION September 1977 679 Oscillator A channel scanning input Other diodes-4F arrangement for 1000p Positive applied RFC RFC voltage A quartz crystals to engage X C2 - 1000p 47Is< > Ro <› Current limit by I. J. DILWORTH, BSc, G3WRT* cetOmA

HE units to be described allow scanning of up to nine

Tchannels and are applicable to transmitter or receiver Fig 1. Basic arrangement oscillators which can be crystal or vfo controlled. For nbfm a squelch circuit is described which can be used to stop the commercial designs. Figs 3a and 3b illustrate values which scan on a channel when a signal appears. A switching circuit have been found suitable for 8MHz using parallel mode allows skipping of unwanted channels or halting the scan on crystals and 45M Hz using series mode crystals. a single channel. The circuitry is readily adapted for use in The output of these oscillators is in the range of 0-8-2V commercial vhf/uhf transceivers which incorporate diode peak to peak and should prove adequate for receiver local crystal switching or alternatively can be used as an "out- oscillator drive and transmitter multipliers while still main- board" unit, connected via the vfo socket. taining adequate stability of the quartz crystal. A perennial problem associated with switching techniques Switching circuitry of this type is parasitic oscillations which are caused by stray The requirement for the crystal switching configuration is inductance and capacitance. Consequently it is important to that parallel or series mode crystals can be switched without keep lead lengths short in order to avoid any instability. loading the crystal and hence affecting its activity. Fig 1 illustrates the basic arrangement used for parallel and series Scanning system mode crystals in the range 4-60MHz. The standard load Reference to Figs 4a and 4b will indicate how the system is capacitor is assumed to be 30pF. arranged. Fig 4a illustrates the led type display of the A voltage applied to point A sufficient to drive the diode channels, a mos type shift register provides the heart fo the into conduction effectively connects the crystal to the oscil- design. This simply scans sequentially along its outputs lator. By using a fast switching diode with small residual recycling at the end of the sequence. The squelch circuit capacitance, the no bias condition isolates the crystal and detects the presence of a signal and via the control circuitry hence exhibits only a very small loading effect on the oscil- stops the scanner on that channel. Switching is incorporated lator. The rf chokes provide an ac block and hence are re- to allow missing a channel or holding etc. quired to be a high impedance at the crystal or overtone The seven-segment version in Fig 4b is identical to the frequency. Combining nine of the basic configurations leads above excepting the seven-segment decoder and additional to Fig 2, the full switching circuit. circuitry to provide synchronization, colon flashing etc.

Oscillator configurations Scanning circuitry An almost universally applicable oscillator which has pre- As briefly mentioned, a mos type shift register can be used sented little difficulty in experimentation is the Colpitts to good effect in this application to drive the crystal switches, arrangement. Not surprisingly this is used in very manj? and while this can be used directly with little current consumption, it does not provide enough current capability to simultaneously drive indicator lights, which are necessary for • University of Essex. Dept of Electrical Engineering Science. Wivenhoe Park. Colchester CO4 3SQ. channel identification. Because this is an essential feature,

1k RFC 1000p 1 --- i-Osclilator Input

CI 32pF p. y,tyrd,r, R D ¶N914 ,C2 2 12 202F var.a1,2

Fig 2. Full switching bank

680 RADIO COMMUNICATION September 1977 +V To suit V +V

100p I--11»- Output Crystal bank --111.- -1 2N2369

(a) ( b )

Fig 3a. 8MHz parallel-mode crystal oscillator Fig 3b. 45MHz series-mode overtone crystal oscillator transistor drivers are used which not only switch the diodes The mos outputs drive BC108 type devices directly. but also provide enough current for led type diodes. Fig. 4c Strictly, base resistors of loon or so should be incorporated illustrates the arrangement. It is worth noting that by con- in order to limit the base current, but with the loading used necting pin 15 to the relevant output stage, scanning of in this application they are superfluous and are therefore 2, 3, 4 ... 9 is possible, the nine-stage sequence is shown here. omitted. With a 9V rail, 30mA drain current through one The mos circuit can be powered from any convenient BC108 is permissible, je 10mA for the diode switch and 10mA source in the region of 3-15V and so does not have to be for one led indicator (see Fig 6). stabilized at + 5V as in the case of ttl, and of course requires The scan stop function is performed by TRI, TR2, while a fraction of the power. TR3 allows holding the scan on a specific channel. The led in The CD4001 package contains four NOR gates, two of TRI collector glows when the scan has been stopped, which are used to form the clocking oscillator. Because of indicating that the squelch is inoperative, this proves very squelch considerations the clocking rate is made deliberately useful when accessing repeaters for example. A small stand- slow and with the values illustrated each channel is scanned ing current is present through the led to provide bias for TR2 for 0.1s approximately; in practice this has been found when the circuit is scanning; however, this is not sufficient to satisfactory. cause confusion between the off and on states of the led. A

Pene.ver Hold. miss, scan - Receiver crystal oscillator switching bank Receiver Hold, m ss,sca crystal oRescl il'alc'ir omit lung bank Tranknutter (a) Transmitter (b) crystal 1- 11,» osc dialer bank Transmitter Transm,tter MOI scanner crystal ox,ilator Control bank circuit 0 o 000 00 0 Scanrung MOS scann Oscillator LED d play

Decoder and Squelch amp 7-segment Squelch amp drivers and and Scanning gate From h.t•'' Fro m oscillator recelver LED receiver duscrim ,natOr discriminator

0.01 Seven• segment display

Fig 4. Scanning circuit

TransIStOe driver stages (c) 711 162 (>4.4V to stop scan whin 0.7V level is required to stop the scan. If it is required to hold +0.6V 761 q v. +9V) the scan on a specific channel a similar voltage level on TR3 stop 4.711 base prevents TR2 being biased on. Scan { Control Squelch circuit TRI, 2 and 3-111C100 A few circuits have been experimented with; generally, however, the configuration in Fig 5 has been found very successful. A broadly tuned LC network selects the high

RADIO COMMUNICATION September 1977 681 CD4001 Mute Squelch pin 11 input switch A OB

+9V See text 33k or fig 7

0.001 0.047 0.1 Si From receiver A A BC109 detector Output

C12 :10k

c-i Switch L to resonate at -L1.-10ki-12

Fig 5. Squelch circuit plus switch frequency components at the receiver detector (ie noise) Channel indicator systems which (hopefully!) disappears when a signal appears. With Two methods are readily implemented. noise present the squelch level control RV1 selects the (a) A single led using different colours for simplex and required level of gating and the signal is amplified by TR4, repeater channels, and a third (say, yellow) for the local TR5. The rectifier and integrator generate a voltage which repeater provide a pleasing display. These can be driven switches TR6. To miss out a channel D3 is used. By applying a directly from the transistor driver on the scan board via positive voltage via this and the 33kI resistor a channel can a I k CI resistor. However, this does not provide any be missed whether a signal is present or not, ie rendered sophistication of channel switching. inaudible provided the af section is muted by the squelch The reader will no doubt be able to configure his or her switch. own arrangement; a suggested circuit which provides The time constants associated with the noise rectifier simple operation is illustrated in Fig 6. The use of one pole ensure positive squelch action. It is quite permissible to two-way centre-off switches can provide all the functions increase or decrease the time constants by varying the capaci- required; which, together with diode switching, allows tors C12, C13, but the scanning oscillator period may then blanking of missed channel LEDS. This arrangement have to be adjusted to ensure positive action. The sensitivity proves to be much neater than using two switches of the squelch circuit is excellent and can be adjusted to stop (it hold and miss) for each channel, and operationally on very noisy signals. it is more convenient.

Channel 0 Channel 1 Channel 2 +V 0 Trtii i 1111 1 1 Channels 3 to 8 From CD4017 CD4C17 CO4017 pin 3 pin 2 111P. pin 4

hold

RFC RFC RFC scan Crystal •"/ 3 switches o miss Switches are centre off, two-way- hold 1 3 miss hold miss hold miss - 0 - --0 Note that centre position is always scan scan connected to the LED Irrespective of LED 1 LED 2 LED 02 scan physical position Channel 0 shown in hold position si V i Si 0 V S1 V s ,

hold

All diodes can si be 0490 or 1N916 Channels3 to 8 To LED3 to 8 1k to 2.2k miss

Fig 6. One possible switching arrange ment (see text) }

682 RADIO COMMUNICATION September 1977 (b) A more sophisticated display using a seven-segment Fig 7. Seven-segment indicator led display has the advantage of providing num- bered channels; using a cmos decoder minimizes the current requirements and one has the added advantage of not needing a stabilized high current 5V supply rail. Fig 7 illustrates thecircuitry involved. As before, two NOR DL704 Comm on gates are used as an oscil- cathode lator in the same configur- display ation using the CD4017 as a decimal output for the crystal switches. A 4023A device contains all the circuitry to decode the input point C (colon) To crystal switches clock pulses for display of and selector arrangement. f ig 6 0 to 9 using a seven-segment DL704 type common 5 '6' Volts RL R 1 6 —1.- +5 15011 1.5k 1315 cathode display. Current To squelch, f ig 5 IC 9 --b.- +9 33011 3.3k drivers are necessary, how- +12 470f1 3.3k ever, to drive the display, 004017 If May need adjustment to obtain equal charging rate of capacitors in squelch circuit a cheap driver device being a 2N3708. The last output digit of the 4017 is used to reset the 4026 counter to zero, simultaneously the display is enabled via the remaining two NOR gates in the 4001

device connected to form a latch. In this way synchro- One channel of nization is assured and the display will not be activated diode switching u It until this condition is reached in the count. The colon segment is arranged to flash at the clock frequency and serves to indicate channel scann ing even if synchronization of the two counters is not complete and hence the main display is blanked off. Pin 11 of the 4001 latch can be +V Tuning used to ensure the squelch does not open before synchro- control nization is achieved by routing another resistor-diode combination parallel to path A in Fig 5.

Very gOOO mechanical rigidity is recu'red for good results

Fig 9. Variable local oscillator. Tuning diode D is varactor Further sophistication type or IN918 with reduced frequency swing One useful modification would be to include selectable delay on the squelch switch in order to prevent the scan starting when listening to a fluctuating signal. This can be achieved scanning clock. Operationally it is better to have this facility either by keeping the squelch open or by inhibiting the switchable. Fig 8 shows one possibility in principle. The crystal switching arrangement can be used for a vfo/vco input to allow reception of channels for which crystals are ifeitth taut not available. The circuit of Fig 9 has been used to good effect although great care in the stability of construction and rigidity of leads is necessary to achieve useful results.

Conclusion The circuitry presented has been in use for over a year. Needless to say, it has proved a very useful means of monitoring many channels at "once". Parallel connection of 4528 Monostaele transmit crystals to the receive bank ensures the maximum Cu ana AA are selected for reeired de'ey convenience in operation. or hang 1.me Impatt Electronics, PO Box 12, Lincoln, have available printed circuit boards and component kits in addition to Fig 8. A possible modification to include selectable delay ready-made units for this project.

RADIO COMMUNICATION September 1977 683 RVIa Simple circuits for 25k

Cl 1000p the beginner RI 150 81A91 'Coaxial I braid LI

,nn er by R. S. McMILLAN, GM8JUY* • L2 De? -v. I braid I I D2 C3 R2 _ 10001F L 0A91 Igko 150 Introduction This article was written with the beginner to vhf in mind. RVIb 1,4 25k The author's own experiences as a new G8 +3 who does not work in any branch of electronics, gave rise to a hunt for simple, functional and relatively cheap designs. The article SI 500»A • describes some equipment the author found, and still finds, handy in the shack: Fig I. SWR bridge circuit diagram A simple, easy to make swr bridge for tuning transmitters and monitoring antenna conditions in the shack. R1,R2 1500 min skeleton pre-set D1,D2 0A91 A noise limiter for inclusion in older or basic receivers. RV1a,b 25kfl tandem linear pot -I- knob A noise generator to aid receiver alignment and performance C1,2,3 1,000pF disc checking. L1,L2 aim n lengths lot 16swg bare copper wire or *in An audio filter to assist the copying of ssb or Cw on older or copper coated steel welding rod 1911 500i,A moving-coil meter basic receivers. S1 SPST min toggle Die-cast box 51in by nin or similar No claims are made as to the originality of the material. Solder tags 4 It is simply a collation of ideas from various sources which Sockets 2 off 50239 have fulfilled the requirements of the moment. BA bolts 8 off to suit the S0239 sockets Coaxial cable 6in of UR67

A simple swr bridge (Fig 1) are gently pushed towards each other, causing the braid to The bridge is built in a die-cast box; the one used in the increase in diameter and decrease in length. The braid can prototype being similar to the RS Components 509-305. Two then be removed and stored, still bunched, until required for S0239 rf connectors (4-hole mounting) are fitted directly refitting. opposite each other halfway down the long sides of the box The inner core of the cable, complete with polythene and high enough up from the bottom to allow all four insulation, is then cut to match the distance between the mounting screws to be fitted. The box sides should be marked pins of the two S0239s plus in. Bare and tin in at each end off and drilled to give four mounting holes for each con- of the cable. nector. These holes should preferably be threaded to accept Measure and cut two pieces of I6swg corer wire 3fin BA bolts which will pass through the holes on the S0239s. long to form LI and L2. The prototype uses in copper- The box sides must also be drilled to clear the rolled-over coated steel welding rod (easily available from garages) flange which secures the insulator on the rear of the S0239s. which have the advantage of being straight compared with When fitted, the S0239s must lie with their flanges flat against coiled copper wire. Copper wire can be straightened by the outer surface of the box sides (see Fig 2). The two screws clamping one end of the coil in a vice and pulling hard on on each S0239 nearest the open top of the box are also the other end of the required length. Clean and tin in at fitted with solder tags. each end of both lengths. Place two l¡in strips of pvc tape, sticky side up, parallel on the bench. The tapes should be approx 2in apart. Place the Bridge unit UR67 inner across the tapes so that the tapes are an equal The bridge clement is made from a piece of UR67 coaxial distance from both ends of the UR67, and at right angles to cable into which two pick-up lines (LI and L2)are introduced. it, then press the inner on to the tapes. The lines are connected to diode detectors and, after decoup- Centralize LI lengthwise to the UR67 inner and lay LI ling, the output is fed to a 500 aA meter. A potentiometer is parallel to and tight up against the inner. Roll the inner over included to allow the unit to accommodate various power LI to make the tapes hold LI tight against the insulation levels. of the inner. Do not roll it too far since the same tapes must also hold L2. L2 is fitted in the same way as LI but is spaced Bridge construction 180' round the inner from LI (see Fig 2). Once both LI and The outer cover is removed from a piece of UR67 about L2 are secured, cover the entire length of LI and L2, except 6in long. The braid is then "bunched"; that is, the two ends the ¡in tinned at each end, with one turn of tape, applied in the same way as the original two strips. • 64 Eglinton Street, Coatbridgc ML5 31IF Remove the right-hand socket. Locate one end of the

684 RADIO COMMUNICATION September 1977 --Long side by adjusting the terminating resistors for minimum reflected of box power pick-up as indicated on the meter.

Solder tag Open the box to allow access to the bridge element. Connect the transmitter and a dummy load, known to be 50f1 at the operating frequency, to the S0239s. Power the L2 transmitter and select the position of Si which gives the lowest reading on the meter: this should be the reflected power. Adjust RI or R2 (depending on which line is selected LI $0239 by S1) for minimum meter reading. If required, increase the socket reading on the meter by adjusting RV1 to ensure that the minimum point is observed correctly. The pre-set resistor should be sealed with nail varnish or measured with an ohm meter and replaced with an equivalent fixed resistor. The fixed resistor should be of the moulded carbon type. Fig 2. SWR bridge construction Stop the transmitter, remove the cables connecting to the bridge sockets and connect them to the opposite socket, je UR67 inner into the left-hand S0239 pin and position the if the transmitter was connected to the left-hand socket, it inner so that LI and L2 lie equidistant from the bottom of should now be connected to the right-hand one. Select the the box. Solder the inner to the pin of the left-hand S0239 other position of SI. This reverses the direction of pick-up and place one turn of pvc tape round the joint. Slide the from the bridge, allowing the second line to sense reflected braid, still bunched, over the UR67 inner and LI and L2 by power. Adjust the second line exactly as the first. Seal or passing it through the hole drilled to accommodate the right- substitute the resistor, then close and secure the box sections. hand socket. Refit the right hand socket and its solder tags. Set RV1 for full scale on the meter, using the position of At the same time locate the end of the inner in the pin of the Si which gives the highest reading on the meter with the socket. When the socket is secured, solder the inner to the connections to the bridge as they will be in the normal situ- pin and tape the joint in the same way as the left-hand ation. It may be that it will be found more convenient to socket. Spread out the braid, making it as tight as possible connect the transmitter to the left-hand socket when in normal over the inner/L1 and L2 assembly. Locate the left-hand end use, in which case this is the way it should be connected for this of the braid against the box side, covering the pin of the step. S0239, and after bending down the solder tags to contact Having set RVI to give fsd on the meter, reverse SI and the braid solder the tags to the braid at the left-hand socket. observe the meter. With a good dummy load, there should Caution: solder the braid as quickly as possible to avoid be very little showing on the meter, indicating a good swr. overheating it! Stretch the braid out tight and trim the This position of Si should be marked REFLECTED or right-hand end of it as required to allow the braid to com- 'REVERSE. The other position of SI (the one which gave fsd), pletely enclose the right-hand S0239 pinfUR67 joint and should be marked FOR WARD. A scale may be marked adja- contact the box side. Check for any "rogue" strands which cent to the knob of RV1 giving a useful reference to the might cause a short to the inner. If none is found, bend down transmitter output, into the same load conditions, over a the right-hand solder tags and quickly solder them to the period. Any change in transmitter output would require an braid. adjustment to RV1 to obtain fsd. The scale does not need to Carefully locate the ends of LI and L2 and, using a small be calibrated, merely marked at the point where fsd was ob- pair of nail scissors, cut holes in the braid strands to expose tained when using, for example, one specific antenna. the tinned ends of LI and L2. Carefully fold back the braid strands to create holes of about in diameter. Lightly solder Results the area around the holes to trap the folded strands. This Tests carried out by GM3KMG and GM4AUP showed a gives short-free access to the ends of the pick-up lines. very low insertion loss at 144 and 432M Hz. The accuracy of Solder DI and RI to LI, and D2 and R2 to L2, as shown in the bridge was not checked at 432MHz, since it was intended Figs 1 and 2. Caution: use long nosed pliers or other heat- for use at 144MHz, but it was accurate at I44MHz. sink on the lead of the diodes when soldering or damage may result! The diodes should be as close as possible to the pick- up lines. The layout of the components from LI and L2 A simple noise generator should be as uniform as possible. Fit Cl and C2 as close as What is a noise generator? It is a simple yet effective method possible to the diodes. of obtaining a signal of constant amplitude over a wide Install MI, RV1, Si on the top of the box: the layout may range of frequencies. The unit described covers from 90MHz be altered to suit the user. Take care that when the box is to beyond 500MHz. This signal is not on a spot frequency closed the components on the top do not foul the bridge unit. like a signal generator or a transmitted signal but on all Wire the components on the box top to the bridge unit as frequencies between these points simultaneously. per the circuit diagram. Carefully check all wiring for faults, What use is this? If the generator is connected to the then close the box and secure the lid. Check the bridge antenna socket of a receiver via a piece of son coaxial cable, element for any short between the inner and the braid. If all and the receiver tuned to, say, 145.5MHz, the S-meter read- is in order the bridge can be connected to a transmitter and ing can be noted and compared with the reading obtained tested. at, say, 144.5MHz. Since the generator output is constant between 90 and 500MHz, any variation in S-meter reading Testing will be caused by the receiver. This gives a useful check of The pick-up lines must be correctly terminated. This is done receiver performance over the band and, if the readings are

RADIO COMMUNICATION September 1977 685 al In the author's case the QRM comes from a central 10X heating pump in the house next door. Depending on the pump load the level of QRM can blot out even local signals. With the noise limiter switched in. the signals are at least readable, although by no means noise free. This circuit has one advantage in that when the spst SI is open, the module is completely out of circuit and therefore cannot produce "funny effects", a problem with some circuits which are merely bypassed when not required. The circuit can be built on Veroboard and connected to the receiver on the detector side of the capacitor feeding the volume control. Switch Si should be mounted where convenient. DI and D2 are BA100/BA114 or 1N916 types.

BC107 An audio filter This filter is very useful for inclusion in the cheaper type of Fig 3. Noise generator circuit diagram hf receiver, especially a general coverage rig. It can be adjusted to cope with ssb or cw. It also has the advantage of recorded, the same test done over a period of time will show providing some amplification, sufficient to drive hi-z phones any deterioration in receiver performance. The same test direct, which compensates for any insertion loss. could be done to compare 144 and 432M Hz converters on an The circuit is based on a 741 dil op-amp with a "bridge-T" hf rig. filter built into the feedback line. Do not be put off by the The noise generator can also be used as described to tune dual supply configuration, the —9V line consumes only 2mA up a receiver, since the receiver will accept it as a normal and does not even require to be switched off. It can be nothing signal on the frequency to which the receiver is tuned. The more than a PP3 battery. This has lasted, in the prototype, S-meter can simply be peaked for maximum. The unit gives more than a year without being switched off. an output of approximately 21.4V up to and beyond 500MHz. The circuit uses the base emitter junction of a silicon transistor, reverse biased, as a noise source. The noise is 741 amplified by a fet (TR 1) and fed via CI to point X. Point X can be used as the output or, if a lower output is required, it Cl can be fed through a 3dB attenuator formed by R3, 4, 5. The 0.1 prototype gave about 214V at point X. This was reduced to 1j4V by an attenuator. The circuit can be built on Veroboard and should be housed in a diecast box. A small switch in the battery line and a Belling Lee or other rf connector can be fitted in the lid. The Veroboard can be supported from these inside the box, giving easy access to the components when the lid is removed.

A noise limiter A noise limiter is something which some people swear by From and some people swear at! It is not a magical device which volume C3 removes all the QRM from a received signal (the author control O-2 wishes it was!). Where it can help is with pulse noise, eg electric motor or ignition interference.

From Existing wiring To volume detector control Fig 5. Audio filter circuit diagram

SI (min spst) switches the filter network on and off and RV1 adjusts the bandwidth. Layout is non-critical and can be built on Veroboard or similar. The ± 12V and —9V supplies are, of course, with respect to the circuit ground rail. It should be noted that an ic holder (8-pin dil) is used. This makes it very easy to install and remove the ic with no risk of damage due to heat from soldering. All unused pins on the ic are left open circuit. Capacitors Cl, 2 and 4 are polyester, C3 disc ceramic, and Fig 4. Noise limiter circuit diagram C5 electrolytic.

686 RADIO COMMUNICATION September 1977 Some experiments with high-frequency ladder crystal filters

by J. A. HARDCASTLE, G3JIR* 330 A 25p 10p 10p 10p 25p lk D E

Output Part 4. SSB transmitter filters Input

Feedback Since the publication of the first three articles on ladder Fig 22. SSB filters. (a) Lower sideband. (b) Upper sideband crystal filters [1-3] correspondence [4] and published sugges- crystals to the same peak loss frequency. Fig 22 shows the tions [5] have pinpointed a need for a cheap ssb transmitter circuits which were used. They are slightly different from filter using crystals which are not necessarily identical in Figs 16 and 17 because of the need to trim each crystal to the frequency. These notes describe briefly two filters which use peak frequency. Cl to C4 are 40pF compression trimmers crystals removed from an ITT 445LQU901A filter. although the actual capacitance setting is noted by each trimmer because it reflects the amount by which each crystal's 445LQU901A 50kHz channel filters frequency was shifted and may be helpful to constructors. These filters contain eight crystals whose reference numbers indicate that there are four pairs of nominally identical Tuning crystals. As shown in Table 1 they fall into two groups of The filters are tested using the test set of Fig 12[2]. During four frequencies which arc sufficiently similar to allow them tuning each crystal must be isolated from its neighbours, and to be used in a four-crystal ssb filter. upper and lower sideband filters each need a slightly different procedure to be followed. In Fig 22(a) the first crystal is isolated by linking points B SSB filters and E. The parallel resonant frequency (le frequency of Figs 16 and 17 [3] showed how a high performance could be minimum output) of XI is then moved closer to the passband obtained from a few crystals if all the selectivity were concen- by increasing the capacitance of Cl. To tune the second trated on one sideband. They were adjusted to provide section. point A is linked to B, point C to E. and C2 is uniformly high selectivity over a wide stopband and it has trimmed to tune X2 to the same frequency as X I. The same been pointed out by John Haine, ex-G8CEG, [4] that the procedure is applied to the remaining sections to complete rate of cut-off can be further increased by tuning all the the tuning.

o o

10 10

20 Fig 23. SSB filter frequency re- -(13 20 o sponse. (a) Lower sideband (b) Upper sideband 30

. 40

10680 82 84 86 88 90 92 10700 2 4 5 8 10 12 ;4 482 Acacia Avenue, Huyton, Liverpool ( a ) Frecuen y (kHz/ (b) Frequency (kHz 1365TP.

RADIO COMMUNICATION September 1977 687 Table 1 is positioned to the passband the steeper the rate of cut-off; however, a point is reached when the passband becomes Crystal case Fig 22 Series resonant Parallel resonant reference reference frequency (kHz) frequency (kHz) restricted and this is illustrated in Fig 23(a). This filter would 0074 X1 10,6807 10,6999 give a better overall response if the rejection notch were 0074 X2 10,680.9 10,6916 moved slightly higher in frequency. 0075 X3 10,6813 10,702.5 A transmitter incorporating these filters requires a lowpass 0075 X4 10,6813 10,7011 filter to limit the audio bandwidth before it is applied to the 10,720.0 0076 X5 10.7006 modulator. Without this additional filter the bandwidth of 0078 X6 10,700.3 10,7199 the transmitted signal will be unnecessarily high. 0077 X7 10,702.8 10.722.8 0077 X8 10,7010 10,722.7 Conclusion These additional designs have been reported to show that the In the upper sideband filter, Fig 22(b), the peak rejection cost of filters need no longer be a barrier to home construc- frequency is determined by the series resonance of the tion of ssb transmitters, even if new crystals have to be pur- crystals. To tune the first section, A is linked to B, and B to F. chased at commercial prices. In this case reducing the capacitance of CI will move the sedes resonance of X5 nearer to the passband so it is useful to set all the trimmers to maximum capacitance initially. For References the second section, A is linked to C, and C to F, and simi- [I] "Some experiments with high frequency ladder crystal larly for the remaining sections. filters", J. A. Hardcastle, G3.11R. Part 1, Radio Communication December 1976. Performance [2] Part 2, January 1977. Fig 23 shows the frequency response of each filter. The [3] Part 3, February 1977. choice of the best maximum rejection frequency will prob- [4] Private communication, 17 January 1977. ably require several attempts at tuning. The closer the notch [5] "Technical Topics", Radio Communication June 1977.

Calculation of distances from QTH Locator codes or latitude and longitude using scientific calculators

by J. H. BOWEN, CEng, MIERE, G8DET;* R. C. HARVEY, TEng (CEI), MITE, G4BBR; and A. J. HARRIES

NU MBER of methods have been described for:calculating 2. G8DET QTH, QTH Locator code AL23b Athe distance between two stations whose positions are Longitude 2 (0) + (0-57) =-. 0.57°E defined by QTH Locator codes. Some methods make use of Latitude 2 (51) -I- (0.73) = 51.73°N computers while others use programmable calculators, both Due to the fact that the QTH Locator code system does being very efficient, especially when a large number of not define a unique location, stations have been worked calculations are required as in tallying up the score for a on 144M Hz with the same QTH Locator codes separated by contest. The authors feel, however, that there is also a need 26° of latitude, je 2,889km. Reference to a map will show for a method of calculating these distances using relatively if the correct latitude (or longitude) has been chosen. A cheap scientific calculators, in fact one machine currently maximum error of ±7km is possible between two European available at under £10 does the job admirably. stations due to the relatively large area covered by the QTH The described process is in two main parts, the first being Locator code tertiary "square". The error may be halved the conversion of the QTH Locator code into degrees if the actual latitude and longitude, expressed in decimal longitude east and degrees latitude north. Locations to the degrees, is used for the home QTH. For dx record purposes west of Greenwich are expressed as negative degrees east. the latitude and longitude for both stations should really The conversion is easily accomplished with the help of be used together with a multiplier of 111.12. Table 1 which assumes the QTH is in the centre of the QTH The second stage involves the calculation of the distance Locator code tertiary "square". between the defined QTHs, and the standard formula for I. G4BBR QTH, QTH Locator code YLI0e. this is given at the foot of this page.t Longitude I (-4) + (1.90) —2.10°E A number of calculators have been tried on the above Latitude 1 (51) + (0.90) = 51.90°N formula and all those listed below will work out the distance without having to resort to pen and paper during the calculation: 62 St Clere's Way. Danbury. Chelmsford. Essex. Hewlett Packard Scientific range;

t Distance = Cos -' [Sin(Lat 1) x Sin (Lat 2) + Cos (Lat 1) x Cos (Lat 2) x Cos (Long 1—Long 2)] x 111km where Long I and Lat 1 is the location of the home QTH and Long 2 and Lat 2 is the location of the distant QTH.

688 RADIO COMMUNICATION September 1977 TABLE 1

Latitude and longitude shown for Europe, extend as required

QTH Locator code conversion to longitude degrees east

Table 1 (a) 1st letter U V W X Y Z A B C D E F G H I J K L M N O P Q R S T U V W X Y Z —12 —10 —8 —6 —4 —2 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50

Number et 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 4s 46 47 48 49 50 51 52 53 54 55 56 57 58 59 so 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 so

Table 1 (b) 1-43 1.63 1-83 f, g, h Last letter f, g, h -03 .23 •43 -63 • 83 1•03 1.23 a. e,J -10 .30 -50 • 70 -90 1.10 1.30 1-50 F70 1-90 a, e, b, c, d -17 -37 •57 -77 •97 117 1-37 1-57 1.77 1.97 b, c, d

Longitude degrees east Table 1(a) + Table 1(b)

QTH Locator code conversion to latitude degrees north

Table 1(c)

2nd letter V W X Y Z A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A B 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67

Number 01 11 21 31 41 51 61 71 to to to to to to to to 10 20 30 40 50 60 70 80

Table 1(d) -02 d,e f Last letter d, e,f -90 •T7 -65 -52 .40 -27 -15 -19 -06 c,g,J e, g, I •94 .81 -69 .56 •44 .31 .35 a, b, h a, b, h .98 -85 • 73 .60 • 48 .23 -10

Latitude degrees north — Table 1(c) + Table 1(d)

Texas Instruments SR50A and SR5IA; Rockwell 44RD and 51R; Commodore CBM SR7919, 1800, 4148, 4190 and 5190; TABLE 2 Prinztronic Scientific 5001. Time precluded further models being evaluated; if in doubt Using 'RPN' Using 'ALGEBRAIC' calculator calculator try the calculation using the authors' example. The calcu- (Using a store) (Using brackets) lated distance is 184km. LONG 1 ENTER t LONG1 EJ LONG I E Table 2 shows the key stroke operations for some of these LONG2 E LONG 2 E LONG 2 E types of calculator including Reverse Polish Notation (RPN) and the algebraic (sometimes called logical) range. 1E 3 ECM E E Some variations may be required but these should be minor LAI 1 LATI LAI I 13:13 E MI E 1E 3 ones. The calculator should be used in the Degree Mode. LAT2 LAI 2 E LAT2 ELM E No key should be pressed until the calculator has completed LAT1 BIB E an operation and produced a display. Westerly longitudes LAI 2 E113 LAT1 13E3 LAI 1 should be entered as: LAT2 EMI LAT2 1313 13031 E E I RC L 111 LONG r n or LONG 1333 111 E FMB cos-11 Cos -0 may be obtained by pressing keys marked 111 111 E a ICOS-I , b IARCOSI or c [ MI and then 13:13 Display= answer in kilometres A second function E may need to be pressed priOr to using a If additional stores are available these may be used for latitude, function eg 1313 longitude and constant as required. o

RADIO COMMUNICATION September 1977 689 Heavy base Metal bridge technical topics r Pat Hawker, G3VA (-NNE often finds that many people, including quite a few amateurs, are positively curious, if not actually dis- believing, when some of us claim to prefer cw to phone r. operating. The appeal of cw is something that very few Gap \ writers have ever really explained. Personally I suspect that adjustment some fairly complex psychological factors are involved, as in so many other apparently straightforward questions of Fig 1. "Sideswiper" morse key built by G400 in 1938 but still personal choice. But one exception was the classic "Morse, giving good service. With modern plastics and epoxy resins he believes that a neater key could be built today at very low keys, keying and codes" by John Piggott, G2PT (RSGB cost Bulletin, May 1956) written before quite a few of the present generation of cw addicts were even born. He noted: "The previous symbol. We were interested to see recently in aesthetic pleasure undoubtedly enjoyed by many cw men is Spalding Radio News (No 19, Spring/Summer 1977) details seldom discussed . .. the attractions of skilful morse of a sideswiper key built by Dennis Hoult, G400, in 1938 operating arc very real. This is 110I to advocate 'down with and which, despite intervening use of various other types of telephony' but rather to proclaim 'long live cw!' ". keys and keyers, he claims "is the easiest and most com- Geoffrey Vore, W9QBJ, in QST in 1974 wrote: "The fortable of the lot ... with a little practice one can become greatest reason for cw remains its complete satisfaction as an quite proficient and easily vary speed of sending without operating medium; solid contacts with moderate to low turning a knob or altering the position of weights! With power, simplified equipment (and expense) and a minimum materials available today—plastic forms, epoxy-resin of ulcer-producing tensions make cw operation sheer adhesives etc they should be even easier to build than in pleasure." Again that emphasis on the pleasure of cw 1938". Fig 1 shows how a short length of blade is clamped operating. at one end to the base and at the other to the paddle. With the Oracle and Ceefax teletext systems now providing telegraphic transmissions to the home at an average APE K—ambidextro us paddle of 50,000wpm and actually sent in bursts at rates of several A novel idea for a home-made paddle for portable or mobile million wpm, it might seem that manual cw at around 20wpin operation of electronic keyers is described by Vidi la Grange, must surely be due for retirement soon. But I have yet to ZS6AL, in Radio ZS (May 1977). The idea is to convert a hear the most enthusiastic teletext addict claim to find standard three-contact jack plug into a keying paddle which reading words on a tv screen a particularly pleasurable plugs into the keyer in those situations where a separate operation in itself! heavy fixed-station dual-lever paddle is inconvenient. The paddle can be turned round in the socket to change the Thoughts on morse keys respective positions of the dot and dash contacts; the paddle The pleasure in cw is clearly dependent upon satisfactory is also suitable for use in the squeeze mode: APEK in fact man/machine interfaces, je the morse key and the actual stands for "ambidextrous paddle for electronic keyers". sounds coming from the headphones. Each form of morse ZS6AL describes construction as follows: key seems to attract its own advocates: the straight "pump- "Obtain a standard three-connector jack plug and remove handle"; the "sideswiper"; the "bug" (auto-dots); the shell; cut off ground connection close to jack body. Drill "elbug" (auto dots and dashes); the "squeeze" mode; and and countersink two opposing holes in plug shell about 8mm "touch" keying. from unthreaded end. The holes should take two 2.3mm by It is not always appreciated that there can be wide differ- 4mm countersunk machine screws. Take two small solder ences in the "feel" between different designs .of the same lugs and connect about 60mm of thin flexible hook-up wire form of key; recently for instance I was fascinated to find to each. Fit one lug to each screw on inside of shell and how an old brass straight key could be improved beyond secure with a nut. Find suitable flat washer which fits over recognition by simply lengthening the arm by about lin. threaded part of jack body and having outside diameter There also seems to have been a marked revival of interest slightly bigger than shell. Prepare two strips of spring brass in the sideswiper form of purely manual key since John about 0.5mm thick, 5mm wide and 40mm long. De-burr Myers, W9LA, wrote in QST a couple of years ago of its edges and bend as shown in Fig 2. Solder strips to rim of flat individuality and the ease with which a short length of hack- washer in opposing positions (simplify this by temporarily saw blade could be made into a key that "gives real character assembling plug). Mark off on underside of each strip the to one's fist". The sideswiper is a sideways moving key with positions of screw heads fitted to shell. Disassemble plug, a contact to each side (as in the bug) but with no automatic clean and tin positions marked on strips. Form small blob formation of either dots or dashes. One simply makes each of solder at these points and file them lightly to give flat alternate symbol on the opposite side of the key to the contact surface.

690 RADIO COMMUNICATION September 1977 Remove the ground lug Solder

Solder blob 20k

Keyed circuit 25 • • 20k 100 0C15R

Flat wash Spring brass Paddle hand le 4

Relay Position of hole (see text) nci 12V Electric tape Paddle handle —9-- 1_ 4 1 250

To collector

Fig 2. Details of ZS6AL's ambidextrous paddle for electronic keyers built using a standard three-connector jack plug for rnrn3 1 4 II 8 use when the fixed station dual-lever paddle is inconvenient

"Solder the two hook-up wires to inner and outer lugs of RELAY jack. Leave wires long enough to survive twisting when o putting jack together. Shape two pieces of old printed- 78° circuit-board to taste or as shown to form paddle handles. Fix them to brass strips with small amount of epoxy. Finally 11100 ) To keye0 circuit one or two wraps of electric tape cut to correct width should 111 -11›.

be wound on to jack shell to provide necessary damping of 10 To -ve othenvise too-springy brass strips. rail

"Contact spacing and spring tension can be adjusted by Fig 4. G3P D's version of ZL3FX's electronic dot, manual dash means of long-nosed pliers. If spring tension is too high, a keyer to overco me need for a particularly sensitive relay small hole drilled through spring at position indicated should do the trick. Then find out by experiment which side activates dots or dashes and mark it for convenience." which "regenerates" or reshapes the waveform to "all or nothing" levels, fed via a zener diode to a relay-driver stage. Automatic keyer The relay contact is in parallel with the normal key or keyer. Although digital electronic memories are increasingly being ON8FM uses this sytem in conjunction with a small used as the basis of automatic keyers, it should not be for- Philips cassette recorder and with break-in so that he can gotten that the ordinary tape recorder can still provide auto- hear any station breaking into the automatic CQ call and keying by using pre-recorded tapes in conjunction with a de revert to manual operation. Since the operator records his relay energized by rectifying the audio output of the re- own -fist" using, for example, a cw monitor, the problem corder, although the simplest systems are not really suitable does not arise that has been noticed on the bands with some for use with small cassette recorders. of the digital systems: automatic CQ calls with good timing A novel and rather more elaborate system (Fig 3) has and at high-speed, followed by a stumbling contact where been described in Radio-REF (No 7, July 1977) by M. the deficiencies of the actual operator are all too evident! Oudart, ON8FM/FOPF. This operates with an af input of only about 0-1V, incorporating a BC109 amplifier after Eldot keyer which the signal is rectified in a voltage-doubler arrangement In the March 77, we included ZL3FX's design for an and the dc level used with a Schmidt-trigger (two 2N3415) electronic dot, manual dash keyer which used a sensitive

+12V

Fig 3. The automatic keyer used by 0148F114 in conjunction with a small cassette tape recorder

RADIO COMMUNICATION September 1977 691 relay actuated by the collector current of a small audio shortwave receivers remains debatable", pointing out "these transistor. He used a home-made relay with some 2,000 circuits are very sensitive to load termination and the input turns of 40 gauge wire and the core of an audio output impedance of most crystal filters changes significantly over transformer. F. Lees, G3PD, attempted to build one of these frequencies outside the passband". DJ2LR then added: keyers but found he could not locate a suitable relay, and "Because of the difficulty in providing wideband impedance tried making one without success. As a result he settled for matching in Errs at high impedances, in my opinion medium- the circuit arrangement shown in Fig 4 which he finds quite to high-level double-balanced (diode) mixers offer an ad- satisfactory, although a little noisy in operation; it also vantage over fet mixers." requires a 12V supply and the relay (RS Components A recent note from Professor Rohde draws attention to a transistor relay type 34-9254 and 11-pin base type 401-712) new mixer he has developed using neither diodes nor Errs is a little pricey. Consumption key-on 100mA, key-off lrnA. but 2N5109 catv-type bipolar transistors in an active system The OC16R is not critical and almost any suitable power of extremely high performance (incidentally in the July TT type could be substituted. the text reference to these devices wrongly gave 2N5019, the It would seem that if a sensitive high-speed relay is avail- diagram correctly gave 2N5109). He writes: able, the original arrangement has advantages, but the "Since modern catv transistors with very low noise G3PD key widens the scope for more readily available figures have a much better gain-bandwidth product, new relays. types of rf feedback can be applied and linear operation can be achieved for second, third and higher imd products that Compact speech-processor for tin were not available with either valves or silicon Errs. Even the A short item by C. J. Blankendaal, PAOCJB, in Electron development of the VMP4 power Errs did not solve the (July 1977, p360) describes a compact speech processor problem because of high input and feedback capacitances. (Fig 5) which can be used with a dynamic or ceramic micro- "Fig 6 shows a new double-balanced mixer using four phone in front of most nbfm transmitters to provide suitable 2N5109 catv-type bipolar transistors in a feed-back arrange- shaping and processing of the audio. It is based on an ment that was outlined in my Ham Radio article. The rf feed- arrangement described in the Motorola Engineering Bulletin back, together with the impedance stabilization stemming EB57. The af output of 5 to 15V could be used directly to from a unique application of the transformer, avoids the phase or frequency modulate a transmitter but the output drawbacks of fet mixers while giving a higher intercept point can be reduced by means of R19. Pre-emphasis of 6dB/ at the same drive level and a low noise figure and stable gain. octave is applied between 300 and 3,000Hz but the active "The emitter resistors reduce the amount of flicker noise filter then rolls off the audio at —18dB/octave. in the system and a 40dBm intercept point is achievable with I3dBm local oscillator drive and there will be very little Improved active mixer degradation with +10dBm drive." In several recent items, we have referred to the controversy DJ2LR enclosed an interesting set of comparative spectra regarding the optimum approach to mixers of really wide of a double-balanced mixer with four hot-carrier diodes, 7dBm oscillator drive with two carriers of OdBm applied; a dynamic range. The advantages of the "double-balanced" double-balanced mixer using a U350 in accordance with the approach are now generally conceded, but should Schottky Siliconix application note; and that achieved with the mixer (hot-carrier) diodes or power Errs be used? The fet approach of Fig 6. Third-order imd products are suppressed by some has been ably argued by Rafuse, Oxner and Racal (for the 65dB, compared with 35dB with the U350 mixer. He points 1772 receiver) but there are clearly problems in reproducing out that "for the same amount of local oscillator drive this their results, as G3RZP brought out in the July TT In his Ham Radio article of October 1976, Ulrich Rohde, means a 30dB improvement with roughly the saine component costs and about the same noise figure". DJ2LR, suggested that fet double-balanced mixers offer advantages in test instruments but "their application in This is thus clearly an active mixer of extremely high performance, although I feel that amateurs must be careful to appreciate that this does not mean that conventional mixers are now obsolete. Everyone would agree that it is a "good thing" to have a receiver that will take all the rf that a " 0•41 : IC1.. MC3401 large antenna can provide from the mass of 250kW broad- D1 MS D6150 cast stations, particularly on the 7MHz band. But equally 100k vcc • — 9Vdc R4 R2 1M R7 1M ! 1M

C3 R11 C5 R12 5 01 a DIP 100k 0 61 200k C2 0.001 C8 C4 500p Voul.

R3 — 12e• 2M 2M

Fig 5. Compact speech-processor for fm based on a design in Motorola Engineering Bulletin EBS7 as used by PAOCJB

692 RADIO COMMUNICATION September 1977 Local osc Heater /loosen

Fig 6. The improved active IF double-balanced mixer of 1511F I extremely wide dynamic range as developed by DJ2LR using catv-type bipolar transistors

one must accept that many amateurs successfully use receivers which have only limited dynamic range and with intercept points negative rather than positive to OdBm. The early FT101 did not show up well in any list of "intercept points"; nor by current standards did the Collins KWM2 or sufficiently predictable nor sufficiently stable for this appli- their "S-line" receivers. But many amateurs were (and are) cation. reasonably happy with the results achieved with these In seeking some alternative form of capacitor, it occurred equipments. Proneness to imd has not prevented the FT101 to G3JIR to look up the characteristics of coaxial cable. The from becoming possibly the most widely used of all hf miniature Uniradio 95 (available from RS Components as transceivers! It is not every hf receiver that has to cope with catalogue number 388-158) has a very convenient capaci- the sort of situation on board naval vessels where receivers tance of 1COpF/m which represents 1pF/cm. This enables are using whip antennas just a few feet away from trans- stable capacitors of values up to about 10pF to be made in mitting antennas being used at the same time. quite a small space. At some £4.77 for a 50m reel the cost is So although dynamic range is a very important and very not insignificant and represents about 0.1p/pF, but it does useful way of sorting out receivers, we need not become allow the production of fairly predictable odd-value capacitors. For example, 2-7cm of cable was measured as 3pF, obsessed about this aspect of performance. If by good front- end selectivity one can reduce the number of very strong and an 8cm length as 8.9pF; measuring the length over the signals reaching the mixer one may (except on 7MHz) find part of the cable covered by the braiding: see Fig 7. things not too bad, particularly if one can cunningly per- He points out that if one side of the capacitor is to be suade all the other local amateurs that it is much more fun earthed such capacitors have the further advantage of pro- on vhf! viding their own electrostatic screen.

Predictable "gimmick" capacitors Battery burping Jack Hardcastle, G3JIR, in the course of his experiments It might be thought that after so many years of battery with crystal filters found that he needed some low-value charging there would be little new to uncover about the capacitors which could not be satisfied by standard values. process, though actually this seems to be far from true. For He was anxious not to use pre-set trimmers because of the example, quite a few years ago Joe Cropper, G3BY, drew constant temptation to alter their settings. He felt that the attention in Ti' to "dirty dc" charging in which an ac com- standard form of amateur "gimmick" capacitor, consisting ponent is retained to cause an "electrolytic shake up" and of two pieces of insulated wire twisted together, was neither noted that this technique was particularly useful in keeping torch and cycle batteries going through several charging cycles even though these are usually thought of as expendable primary cells. This idea has been included in several editions It of Amateur Radio Techniques although one seldom hears of it being used. But an echo of this idea is now attracting considerable attention across the Atlantic in the charging of both lead- acid and the larger categories of nicad cells. One reason for this interest in battery charging, as I found on a couple of Fig 7. Short lengths of miniature coaxial cable used to form low-value capacitors of predictable value as used in crystal trips to the USA, is that the television companies over there filter experiments by G3JIR have very rapidly swung over to using lightweight electronic

RADIO COMMUNICATION September 1977 693 cameras and U-matie video recorders instead of film time between burps is controlled by RIO. Capacitors C2 and cameras for "electronic news gathering" (eng). This rush to C3 charge to 20V. When relay KI activates, a negative electronic journalism soon brought the tv teams into contact charge is dumped into the battery. with all those problems of JP operation so well known to "Burping continues after the battery is fully charged. But amateurs. One heard complaints of multi-connector plugs the time between burps should be adjusted to correspond to and sockets that were too easily damaged; the difficulties of the chemical activity in the battery—a short time for high establishing instant microwave contact with base because of activity when the battery charge is low, and long when near unfamiliar sites and/or interference from competing teams; full charge. The duration of the negative pulse is short, so it the need for much maintenance of electro-mechanical will not harm the battery. But be careful—with the battery equipment; power consumption that showed up the limita- mounted in an automobile, the alternator rectifiers can be tions of batteries (often carried in battery belts developed damaged if the positive cable to the battery is not removed." for earlier film operations); leakage of silver cadmium batteries and short life of nickel-cadmium unless charging Radioactive meters conditions were carefully observed.... A note by ZL1VP in Break-in (January/February 1977) Most of these problems are being rapidly overcome (and draws attention to the radiation (three times maximum it is salutary to see how quickly American development dosage level permitted by New Zealand's National Radiation engineers can move when they need to). One of the rece,nt Laboratory) which he detected coming from the luminous innovations is the use of battery chargers that burp; that is dots on a meter taken from a wartime ZC1 transmitter (a to say, they apply short higher-voltage pulses during the type which has been widely used by New Zealand amateurs). charging process. It is claimed that this tends to shake gas Subsequently a number of other ZC1 meters were tested with molecules loose from the battery plates, so preventing the roughly similar results and a radiation*pectrometer analysis molecules from insulating portions of the plates and hence detected the element radium. Meters dabbed with luminous reducing the effective charging current by raising the internal paint were at one time readily available on the British surplus resistance. market and some must still be in use, though we have no idea By using this burping technique it becomes possible to use how these compare with the ZC1 meters. larger charging currents and significantly shorten the ZL1VP points out that the greater risk exists when ser- time taken to recharge a battery. For instance, with some of vicing these luminous meters. He writes: the sealed cylindrical nicad batteries used in eng it is said to "Inhaling tiny dust particles of the luminous meter face dots be possible to recharge these fully in 15 to 20min, compared (which physically crumble off the painted brass meter plate) with conventional charging times of up to 16h. or ingesting similar small particles carried via skin contact to In an "Ideas for Design" note in Electronic Design 12, food could be injurious. Should it be necessary to service 7 June 1977, John Okolowicz describes a burp charging unit these meters do so in a stainless steel sink. When completed, (Fig 8) for conventional I2V lead-acid car batteries. This scrub your hands and the sink with soapy water. delivers 20V burps at controllable intervals from once every "As laboratory radiation levels defined are for maximum 2s to once every 2-¡min, using a 555 timer ic. He states: limits, exposures at lower levels will not free you from all "This burp-control circuit can be added to just about any risks; less, the safer, proportionately. existing I2V charger. The 555 timer is connected in a free- -Lastly, check that box of old meters and clocks. It could running mode and has independent on and off times. The be time for a clean out."

¡ RI 01 30 A v Ammeter 5w 7)2 0 to !OA 12V Charge 03 SCR! 135 R2 het 1N4001 30 7\0 4 21,11843 5w mDA9721 R4 iVV Toad F41X 47 P LAI +0 1W SCR 2 C106Y1 .1-05 7'100 RLA Time control A DI 2 1 Burp P& B KUP 1N4001 tab./ lIght To 2V 110/5 12V 120 battery R8 C2 Cl r -r a ik 12000 I TRI t:100 40V 2N4237 25V L

Fig 8. Burp-control circuit added to a 12V battery charger in order to apply 20V pulses to a charging battery at intervals adjustable fro m about 2s to 2j-min, determined by the setting of the time control resistor R10 (Electronic Design)

694 RADIO COMMUNICATION September 1977 most interested in trying to arrange schedules for these bands. microwaves G4BEL (Cambs) reports that on 21 May he worked PAOVV (Delft) on 2.3GHz, when signals were S9 ± 20dB, The Dutch station was using just 2W fm but G4BEL was using his full rig: 20W ssb into a dish 5ft in diameter fed by a Dain Evans, G3R PE* log-periodic feed. His receiver is the W2CQH interdigital design (QST January 1974) with two "Birkett Specials" as rf Microwave round tables preamplifiers. So far G4BEL has worked only two other A second round table will be held at 2pm on 8 October in the stations on this band, G3LQR and G4BYV. This is hardly Department of Electrical & Electronic Engineering, Mappin the fault of inadequate equipment on his part. Street, Sheffield. There are a number of new callsig,ns appearing at these Another in the series of round tables will be held at the intermediate frequencies. For example, GM3JFG and IBA Engineering Headquarters, Crawley Court near Win- GM3PLL now have wide-band equipment for 3-4GHz, and chester on 13 November. G8ARH can now generate 2W at 5.7GHz. Apparently G3BNL had a contact on the latter band from his new home 1-3GHz news in Harrow with G8ADC on Dunstable Downs, a by-no- One of the facts of life a columnist has to live with is that the means easy path. Perhaps now would be an especially day after writing of the lack of news, cg about activity on appropriate time to try and produce an accurate record of 1.3GHz, then literally the next day the letters begin to arrive. those who are active at these intermediate frequencies. For example, G4BYV reports that on 22 June PAOVV (CM72d) in Delft worked GW8CFQ, and he wonders if The GB3ALD lOGHz beacon this contact is in any way a "first". GM8BJF also worked the On 14 July the new lOGHz beacon GB3ALD came into Delft station from St Abbs Head (YP) and was also heard S9 service. This is sited on the nearest of the Channel Islands, by SM6HYG, whose transmitter unfortunately was not Alderney, which is approximately 901(m south of Portland working at that time. On 10 July G3OSS in London worked Bill. The beacon uses a Gunn oscillator which feeds a DKIZD (EN) at S5/7, SK6AB and SM6FHZ, all with 15W sectorial horn antenna of 15dB gain. The main beam covers rf and a single quad-loop Yagi. His receiver used a BFR91 the south coast from at least Start Point to Beachy Head, preamplifier to a Microwave Modules converter. The although it surely will be heard in other directions, cg in distances covered are of course in the region of 1,000km. France, which at its nearest point is only about 151cm away In a later letter, G4BYV summarized other recent contacts. according to my map. Both G3LTF and G3JXN worked SM6FHZ, and the latter The beacon has already been heard by G3VPF at Ring- also worked SK6AB. G8LEF (Huddersfield) recently had a stead Bay. G4CNV has also heard it from his kitchen at contact with SM6ESG, and a newcomer to the band, Preston near Weymouth. The signals display the deep fading G3WSN (Chelmsford), worked ON6AT/A (BL) despite the characteristic of this type of over-water path. On the evening latter using only 500mW. G8GML (Cambs) has also worked of 31 July some of the fades were associated with the passing the DK1ZD station. of ships, which surely indicated that super-refraction was G3LQR (Suffolk) has worked the following stations: one of the propagation modes operating at that time. The SM6FHZ, DK1GJ (FO), DK1UC (FN), DC8BB (EL) and same morning it was heard by both G3J VL and G8D1C from ON6AT/A. G4BYV (Norfolk) has worked DK1UC and the latter's home on Hayling Island. Even from the bedroom DJ8X0 both S9, DC8BB, DK1ZD and ON6AT/A. Appar- window the antenna height was less than 10m asl! Later that ently the beacon D1301Z (EN) is off the air while it is being evening G3JH M heard the beacon from a site 10km north modified. G4BYV's current score on this band is 106 of Chichester, over what must be a path length of 170km — stations in 26 different locator squares. and this must be some sort of record. G3SBV (Streatham Common) reports that he and his Clearly this and the other lOGHz beacons are proving junior operator G8LXZ are now operational on 1,296MHz invaluable in indicating one thing that badly needs to be using the 5W ssb generated from the G3LTF/G3WDG demonstrated—that openings at this frequency may be far mixer described in the January 1976 issue of Radio Com- more common than we tend to believe. In this, the detailed munication. The antenna being used is again a single quad- observations supplied by G8BCO and G8ARO for the loop Yagi. A 2C39 pa is being constructed. G3RQZ, who is a London beacon GB3LBH on the morning of I July are a local, has also been encouraged to come on. G3SBV raises most valuable record of one particular event, and something again the topic of an activity evening on the band. Directly I would like to see more of in the future, if possible. on 1,296MHz? GM4DIJ and GM8BJF are considering the possibility of establishing a 1,296MHz beacon in the Edinburgh area. Commercial Gunn oscillators This would be sited at the university's electrical engineering The standards amateurs demand in terms of reliability of tuning and frequency stability from their Gunn oscillators department and would have a clear take-off to the west, is really very high indeed. After all, an If. bandwidth of through north to the south-east. 100kHz at lOGHz represents just one part in 100,000 which 2.3, 34 and 5.7GHz news is pretty good going for a free-running oscillator. Under- standably, much effort has been put into the design of such GM3FYB will be on the Isle of Man over the weekend 10/11 oscillators by amateurs, with much success in some cases. September with equipment for 2.3, 14 and 5.7GHz. He is Apart from the Gunnplexer units which were designed • 4 Upper Sales, Chaulden, Hemel Hempstead. Herts. (continued on page 698)

RADIO COMMUNICATION September 1977 695 France by working F1CFD. The equipment is an FT620 prime mover and a Modular Electronics 432MHz trans- 4-2-70 verter with a 54MHz video converter between the camera and the transverter input. Using this equipment two-way fast-scan contacts have also been made with Gl8AAZ and : ::ham Knight, GM8FFX* GJ8GDX. Pictures have been received from F1ANH and F5YX/M. On Guernsey the outstanding signal from GU3HFN in the August 70MHz contest was due to the four-over-four Convention—British style antenna which was mounted on an 80ft mast. The Guernsey club is now hoping for some northern GM contacts to get The Winning Post Hotel at Twickenham is the familiar into the "Real DX" section of 4-2-70. setting for the 1978 VHF Convention which will be held there on Saturday 25 February. Plans are already being made to involve the audience in the talks and seminars which New transistors will be held in the school adjacent to the hotel during the Following the success of the SD306 transistor two new day. The emphasis in the evening will be on informality—no devices of interest to vhf enthusiasts are announced by Sig- speeches or dinner jackets—but bring a partner as VHF netics. The SD307 is suitable as a mixer with 15dB conversion Committee member G3DAH has already suggested the first gain at 600MHz, and the rf transistor SD308 has a gain of RSGB disco. 20d13 at 1GHz with a 4.5dB noise figure.

Convention—American style First "Supreme" of 1977 goes to G3FIJ It is interesting to know that British vhf equipment is selling G5U M, the vhf awards manager, reports that it was dis- tinctly unusual to be asked to issue three 432MHz Senior well in America and that two British companies had stands Awards in one week. They went to Colin Morton, G3DY, of at the recent Dayton. Ohio, convention. Ian Barton, G3TYE, of Polar Electronic Developments and Richard Porter, Peterborough (No 34), Angus McKenzie, G3OSS, of North London (No 35), and Frank Howe, G3FIJ, of Colchester G3VXK, of Microwave Modules were amazed at the atten- (No 36). As G3F1J already held two Seniors, No 39 for dance which exceeded 25,000 visitors. Both companies not 144MHz and No 25 for 70M 1-17, securing his third Senior only sell their full British range in America but also make automatically qualified Frank for Gold Leaf Supreme special converters and transverters specifically for the Award No 17. American 50MHz band. There is a large swing back to vhf Details have not been published for some time of the ssb in the USA and it is good to see British designed and present FMD certificates which are issued free to qualifying manufactured equipment being exported in quantity to members by G5UM. Standard and Senior awards are America. obtainable for each band but with different qualifications. These are: First G-DL crossband 70/432MHz Standards Awards On 11 July Rolf Nietind, DK2ZF, in QTH locator FNO4j 70MHz-3 countries and 30 counties heard G3ZEZ at Clacton-on-Sea on 70MHz cw at RST539. 144MHz-9 countries and 40 counties Rolf replied on 432MHz and this is believed to be the first 432MHz-3 countries and 20 counties crossband 70MHz to 432MHz contact between England and Senior Awards Germany. Next day Rolf worked even further to G3RJR at 70MHz-6 countries and 60 counties Birmingham, a distance of 859km. Both GB3SU, the Derby- 144MHz-15 countries and 60 counties shire beacon on 70.695MHz, and GB3SX in Sussex on 432MHz-9 countries and 40 counties 70.685MHz have been good signals in Germany on several A special Gold Leaf Supreme Award is available to occasions and DK2ZF is interested in further crossband members holding three Seniors or two Seniors and a contacts. Rolf, who uses a Jaybeam four-element antenna 1,296MHz award, so far 17 amateurs have achieved Gold and a Microwave Modules converter for reception on status. 70MHz can reply on either 28.750MHz, 144.120MHz or Further details of the above RSGB awards and many other 432.200MHz. For skeds contact DK2ZF at 2407 Bad international awards are contained in Amateur Radio Awards Shwartau, Lerchenstr 10. obtainable from RSGB HQ.

Channel Islands firsts Events for your diary Syd Smith, GJ8EZA, worked UC2AAB at a distance of This year's Scottish Convention is being held at the Adam 2,074km via sporadic-E on 8 July at 1135gmt. This is believed Smith Centre in Kirkcaldy on 10 September. G3RPE, to be the first-ever contact between Jersey and White Russia. G3OUF, G6JP and G3DAH are among the vhf personalities Syd has overcome the problem of living in a valley in a who will be attending this event. Further details from most unusual way. His antennas are mounted on a 50ft GM3YOR. tower at the top ola 200ft hill near the home location. At the A large attendance is guaranteed for the popular North top is a remotely-controlled 40W linear and a pre-amplifier West Convention at Lancaster University on 17/18 Sep- fed from 250ft below by an FT221R. tember. Pat Gowen, G3I0R, the acknowledged Oscar expert, GJ8EZA is also active on 432MHz television and recently will be giving two lectures on satellite communication—one made the first fast-scan television QSO between Jersey and for Oscar beginners and another for advanced Oscar users. Full details of the event arc in the July Radio Communica- • PO Box 49, Aberdeen AB9 8M. tion.

696 RADIO COMMUNICATION September 1977 The University of Aston, Birmingham, is the venue on Moonbounce 19 November for a slow-scan television exhibition and David Price, GW4CQT, at Cwmbran, is following in convention being organized by The British Amateur Tele- G3LTF's footsteps by becoming interested in 432MHz vision Club. The event lasts from 10am to 5.30pm. Further moonbounce. He has just completed the special antenna; details from G8DLX, QTHR. a very large array of 12 16-element quads, all made in his workshop. It is mounted at a height of 30ft, the full steering gear is being tested, and all the phasing harnesses are finished. Sporadic-E reports May, June and July have all been good months for those Tropo conditions amateurs working sporadic-E dx. As these reports are of The Glenrothes group expedition by GM3YOR and scientific interest to many people it is again proposed to deal GM3OLK got off to a good start when they tested the with them in detail. equipment from near Peterhead. From the rare square of ZR Tim Hordley, GW8BXQ, (XL26g) caught an early opening they worked stations all over Britain on the three vhf bands. at 0950gmt on 25 May when he worked 1T9JLG in locator However, by the time the expedition got to the Shetlands the GY74j at a distance of over 2,000km. On 14 June, Jack Hum, good conditions had faded considerably. G4DZU and G5UM, was listening on 70.26MHz fer any mobiles on their G4CMV were good signals on 144MHz, as was G8GXP way home when he found the frequency was useless due to who unfortunately did not hear GM3OLK/P calling from S9 signals from eastern Europe navigation transmitters and ZT square. Contacts were also made from Shetland on Polish radio stations. Changing quickly to 144.050MHz cw 432MHz but not over the distances worked a few days brought a contact with LZIFO and an incomplete QS0 with earlier. John Aitken, GM8NFG, at Deerness, Orkney LZ2DAX. Jack says it was particularly noticeable how fast Islands, recently acquired an FT22IR and has been a good the 144MHz cw operators realized there was an Es opening. signal in the London area with his IOW of ssb. It will be most On 25 June Andy Brown, G4EZT, and Graham Brant, interesting to see how John fares in the next aurora. On G8KBW, were in the middle of a radio tour around the 13 July DL7QY in Berlin had a good cw contact with West Country and had stopped to operate from a 600ft as1 EI6AS in WN59g. site near Barnstaple in Devon. After working some stations Conditions on 432MHz were very good in the first two 300 miles away on fm they suddenly heard two Spanish weeks of July, with GM3UU in Aberdeen working Nor- stations on 145.500MHz. They quickly changed over to their wegian stations with an indoor dipole. LA6HL and LA3EQ Trio TS7010 on ssb to work in quick succession HG90C, have joined LA3WU on 432MHz ssb and all three have been 0E3GHA, HG5KDQ, 0E3XUA, HG5AIR, HG4YF, working many British stations. G8AGU in Devon has been SP9AFI/9, 0E5UKL, 0E6KUG/P, HGIKVP/P and finally working his usual pile of dx including many German stations, YU1NOU in locator JEO9h at a distance of 1,900km. They DM2CPA and 1,145km to OZ5GF. noted that the opening lasted from 1400 till 1615gmt. On the same day Dave Price, GW4CQT, worked many Austrian Meteor scatter on 144MHz and Hungarian stations but found it frustrating that the Clause Neie, DL7QY, worked GW4CQT on 16 July in a opening was confined to a small area, albeit 2,000km away. QSO which took one hour to exchange 26/R27 reports. On 8 July Paul Widger, G8AGU, in Devon, worked Fourteen bursts and seven pings were received during the UC2AAB near Minsk in locator NN18c at a QRB of contact via sporadic meteorids. Dave Price, GW4CQT, has 2,079km. On the same day GM6XI/M in Kintyre (XP53a), been spending a lot of time concentrating on sporadic GM8BKE in Glasgow and GM4DGK/P at the Cairn o' meteor contacts and has been rewarded by contacts with Mount (YQ08g) all worked strings of Italian, Hungarian YO2IS, DM3ZBA and SM7AED. and Yugoslavian stations on ssb around lunchtime. On 12 July Ron Marriot, G3LTN, at Banbury, Oxford- shire, worked Y02IS, HG8KP and HG5KDP at S9 signal The grapevine strengths. This opening was quite short, lasting only from Interesting to see items from 4-2-70 being reprinted in a 1404 to 1427 gmt. number of publications varying from Wireless World to the Anyone who has worked sporadic-E dx this season is Belfast Telegraph and on tv teletext... G3NMY and asked to please send reports to GM8FFX indicating beam G8M WV in Norfolk have a nightly sked on 144.420MHz heading, locator, signal strengths etc; all the reports will be with both stations beaming to GM hoping for, breakers... collated and sent to the RSGB Propagation Studies Com- No reports yet of reception of the Lannion beacon on mittee and to the various other interested bodies detailed in 50-1MHz QTH locator hunter G3POI wonders if anyone last month's report. would like to make a boat trip to St Kilda (VR) or to Rona(XT) ... VHF manager G3OUF has been to the USA to get first-hand information on their repeater scene and to Data transmission study Ed Tilton's sun research project.. . Both GB3TW and There are now quite a number of amateurs in the London GB3NEE were off the air recently while workmen painted area who are taking advantage of the new licence conditions the IBA mast—apparently the painters would not work if by sending data on the 144MHz band. In view of the in- any of the high power transmitters were operating. creasing numbers of data operators the VHF Committee may suggest 144.550MHz as a data calling frequency. This would Late news leave 144.500MHz and 144-600MHz as calling frequencies The first auroral opening since May was noticed by G3IPV for sstv and rtty respectively. Details of QS0s and equipment at 0520gmt on 29 July when Swedish stations were heard used by data operators would be appreciated for inclusion working to Norway on cw. SK6JF/OY arrived ok in the in 4-2-70, as would comments on frequencies. Faroes and has been worked on 144MHz. GM3GNRIP at

RADIO COMMUNICATION September 1977 697 outer London 12-14 September. Details from G3ZKE, QTHR, tel 01-485 7065. REAL DX 1977 London (Paddington). Amberley Street Evening Institute, 70MHz G4CVI—GM3ZBE 650km Paddington. Thursdays commencing 29 September. Enrolment 144MHz G3ZEM —U05BF 2,400km 8 and 12 September. Details from G8ELB, tel 01-864 4411 ext 39. G8AGU —OZ5GF 1,145km Loughborough. Loughborough Technical College, Radmoor, 432 MHz Loughborough, Tuesdays, 6-7pm morse, 7-9pm theory and practical, commencing 20 September. Enrolment 6-8pm, 12-14 Sep- tember. Fee: £8.05. Details from head of department of electrical engineering, tel 0509 215831. Orkney and GM8M.IV'P at Lowther were both in big Newcastle-upon-Tyne. Gosforth High School. Gosforth. demand during the 144MHz QRP Contest. Best dx for the Newcastle-upon-Tyne. Theory, Tuesdays, 7-9pm; morse, Thurs- G M3OLKIYOR Shetland expedition was DC1XC who was days, 7-9pm, commencing in September. Details from G3FPE. OTHR, tel Newcastle-upon-Tyne 668439. worked on 144MHz and even on 432MHz. YU4BYZ in Newtownabbey. Technical College, Newtownabbey. Commenc- locator IE17f was the first ms station heard via the Perseids ing September. Details from the principal. at Aberdeen. GB3LER, the Lerwick beacon, came into Newport. Newport ARS, Brynglas House, Brynglas Hill. Newport. Mondays, 6-8pm, commencing 19 September. Fee: £7. Details service on 30 August. from GW3YTJ, 2 Durham Road, Newport. Finally, thanks for all the letters and reports. Please send St Austell. Mid-Ccrnwall College of Further Education, Palace details of your 4-2-70 activities to PO Box 49, Aberdeen. ri Road, St Austell. Tuesdays 7-9pm. com mencing 27 September. Enrolment 5-7.30pm, 21-22 September. Details from G4DND. QTHR. tel St Columb 479. Sheffield. King Edward VII Lower School, Darwin Lane, Sheffield 10. Wednesdays 7-9pm, commencing 28 September. Details from G3JON, OTHR. RAE Courses 1977-8 Southend-on-Sea. College of Technology, London Road, Southend-on-Sea. Enrolment 5-7 September. Details from G3KMT. (See also the list on page 627 of the August issue) OTHR, tel Southend-on-Sea 353931 est 043. Swindon. The College, Regent Circus. Swindon. Mondays 7-9pm, Aldridge, Walsall. Tynings Lane Evening Institute, Aldridge, commencing 12 September. Enrolment 1, 2, 5 September. Details Walsall. Tuesdays com mencing 20 September. Enrolment 15-16 from G3NPM, tel Swindon 29141. September. Wellington. Telford ARC. Details from G8MXS. Bangor, Co Down. Technical College, Bangor. Mondays and Wigan. Wigan Adult Education Centre. Parsons Walk, Wigan. Thursdays, commencing 20 September. Enrolment from 7 Septem- Mondays com mencing 19 September. Enrolment 12, 15, 19 Sep- ber. Details from GI3WSS, QTHR; tel Ho lywood 4277. tember. Fee: £13. Details from G3RCA, QTHR. Belfast. Cregagh Technical College. Com mencing during Septem- ber. Details from college principal. Birmingham. RAE Mondays and Wednesdays commencing 19 September. Morse Thursdays com mencing 22 September. Enrol- ment during week commencing 12 September. Details from G3KPT, M ICROWAV ES OTHR. Boreham W ood. Boreham Wood College of Further Education, (Continued from p 695) Elstree Way, Boreham Wood, Herts. Tuesdays and Thursdays, 7-9pm, commencing 20 September. Enrolment 4-8pm, 7-8 Sep- especially for amateur use by Microwave Associates. Gunn tember. oscillator/transceiver units are available from various Brentwood. Brentwood Adult Education Centre, Brentwood, manufacturers in the UK. including AEI, MESL. Mullard Essex. Thursdays, 7.30-9.30pm. Enrolment at Bishops Hill Centre Rayleigh Road, Hutton, 7-8.30pm, 13 September. Details from and Plessey. It would be most useful to learn of experiences centre, tel 0277 216722. with these devices so that the information can be passed on. Brldgnorth. Bridgnorth College of Further Education, Stourbridge Road, Bridgnorth. Wednesdays, 7-8.45pm, commencing 14 Sep- tember. Enrolment 6.30-8.30pm, 7-8 September. Fees £10 (e for Pre-amplifiers for 1.3, 2.3, 3.4 and 5.6GHz students under 18). In the 1/77 issue of DUBUS-INFO, DL7QY gives details Chippenham. Chippenham Technical College. Cocklebury Road, (including pcb layout) of pre-amplifiers for these bands Chippenham. Enrolment 2-4pm, 6-8pm, 1-2 September. Details from head of engineering department or course tutor at college. based on relatively inexpensive NEC stripline transistors, Crawley. Adult Evening Centre, Sarah Robinson School, Ifield, details of which are: Crawley. Mondays, 7-9pm, commencing 26 September. Enrolment 1-3GHz 2.3GHz 3.4GHz 5.6GHz 7-9pm, 14 September. Details from course tutor, tel Crawley 22540. gain NF gain NF gain NF gain NF Dudley. Dudley Technical College, Dudley. Tuesdays, 6.30-8.30pm, dB dB dB dB dB dB dB dB commencing 13 September. Details from head of electrical engin- NE73435 12 3.8 7 4.8 — — — eering and science department, tel Dudley 53585. NE02135 13 2.0 11 2.8 6 3.8 — Harrow. Hatch End High School, Harrow. Wednesdays, 7-10pm, NE57835 14 1.7 12 2.5 7 3.5 5 5.5 commencing 28 September. Enrolment 10am-3pm. 17 September N E22235 16 1.5 14 2-2 9 3.2 7 4.3 at Nower Hill High School. Details from G8ELB, tel 01-864 4411 Est 39. G4BBR reports that these devices are available in small Knottingley. Knottingley High School, Knottingley. Tuesdays, quantities from Auriema Ltd, 442 Bath Road, Slough Sil 7pm. Enrolment 19 September. Details from G3HC W, QTHR. Leeds. Airedale and Wharfedale College of Further Education, 613B. Prices range from about £3 to £13. Calverley Lane, Horsforth, Leeds LS18 4RO. RAE Tuesdays, 7-9pm, This remarkable issue of DUBUS also includes 3.4 and commencing 13 September. Morse Mondays, 7-9pm. Enrolment 5.6GHz converter designs, and a 100W linear amplifier by 5-6 September, 6.30-8.30pm. The college also hopes to hold an advanced amateur radio course designed for newly-licensed ama- W6I0 M which uses a pair of 2C39s. teurs, covering choice of equipment, its adjustment and detailed operating procedure. Details from R. G reenhalgh, GBLEX, head of Waveguide components engineering, tel Leeds 581723. If only in self-defence, may I be permitted to point out that London (Chingford). Friday Hill House, Simmons Lane, Ching- lord. Mondays, 7.300m, commencing 19 September. Enrolment on waveguide 16 and 20 components, for 10 and 24GHz first night. Fee: £8. Details from G8EAY. tel 01-500 6034. respectively, are available from: Don Hayter. "High Peak —, London (Holloway). Grafton Radio Society Holloway Institute. Telegraph Lane, Fourmarks, Alton, Hants. A sae will Whittington School, Highgate Hill, N19. Mondays, 7-10pm. commencing 19 September. Enrolment: ILEA areas. 8-9 September; produce a list. TI

698 RADIO COMMUNICATION September 1977 Acknowledgements are made to City & Guilds of London A new look for the Radio Institute for their assistance in the compilation of this Amateurs' Examination article. Copies of the syllabus pamphlet, price 40p, are available from the Sales Section, City & Guilds of London Institute. by R. J. HUGHES, G3GVV, Chairman of 46 Britannia Street. London WCI X 9RG. Advisory Committee for Radio Amateurs' Examination of the City & Guilds of London Institute oscar news The purpose of the RAE is to provide a basis from which a potential radio amateur may commence "self-training, intercommunication and technical investigations", without causing interference to other services. Starting with the May 1979 examination, there will be changes both in the syllabus, and in the form of the exam. USSR amateur system RS The major syllabus change is the elimination of valves Circular 1273 from the International Frequency Registration and the substitution of transistors. In recent years both Board, an organisation of the ITU, provides advance details valves and semiconductors have been included but the former of a planned satellite network to be established by the USSR. arc becoming obsolete—by removing them from the syllabus A summary of the information is given below: instructional time is saved, and it is considered that a person General information. The USSR Administration wishes to with a knowledge of semiconductors is capable of inves- inform member countries of the ITU that the USSR is tigating the use and application of valves without causing working on the establishment of an amateur satellite service avoidable interference. There is a reduction in the syllabus system. This system ''RS" will be based on 3-4 satellites on a content relating to basic electricity and magnetism. Additions circular near-polar orbit. The amateur satellite stations are to the syllabus include specific reference to single sideband designed for multiple access with retransmission and fre- and frequency modulation. quency translation without demodulation on a real time The examination will consist of two separate papers. The scale. first, lasting one hour, will deal with licensing conditions and Date of bringing into use: 1977-78. transmitter interference: the second, lasting lt hours, will Number of satellites: 3-4. deal with operating practices and procedures, and with Orbital information: theory; there will be a 15min break between the two papers. Inclination, 82. Altitude of apogee and perigee, 950km A candidate must take both papers at his first entry; if he (circular orbit). Period, 102 min. fails one paper, he need only retake that paper. Uplink characteristics: Both papers will consist of multiple-choice questions 145.8-1459 MHz (100kHz bandwidth). Quarter-wave (Paper 1 with 35 questions. Paper 2 with 60 questions). receiving antenna, circularly polarized. User uplink power, A multiple-choice question consists of a sentence in which 10-15W to 10-12dB antenna. Transponder receiver noise a question is either asked or implied, followed by four possible temperature, 3000°K. answers, only one of which is correct. The candidate is Downlink characteristics: required to select the correct answer. Here is an example: 29.3-29.4MHz (100kHz bandwidth). Half-wave transmitting antenna, circularly polarized. Transponder power, Poor frequency stability of an amateur transmitter can result 1.5W peak to OdB gain antenna. in Maximum conununieations distance: 6,000km (3,700 statute (a) The generation of parasitic oscillations. miles.) (b) Operation outside the amateur bands. (c) A reduction in power output. From the advance publication orbital information it seems (d) Difficult adjustment of the power amplifier stage likely that the "RS-Oscars" will be launched piggyback with the meteor meteorological satellites from the Plesetsk launch The main reasons why multiple choice questions have been site. introduced are: This new series of Soviet amateur radio satellites is (i) a much wider coverage of the syllabus can be given; welcomed in the spirit of international friendship and (ii) there is no choice of questions, so that all candidates co-operation. are attempting the same questions; It will be noted that the output of repeaters using IARU (iii) there can be no variation in marking standards by channels R8 and R9 fall within the uplink passband of the different examiners, as all marking is carried out by an Soviet satellites. This could cause problems, particularly in electronic mark-scanner; West Germany where there arc a number of repeaters using (iv) Because candidates are not required to express their these channels. answers in their own words, their performance is Preliminary information indicates that probable determined primarily by their technical knowledge and "windows" for the launch of the first Soviet satellite are 1 understanding. and 17 October.

RADIO COMMUNICATION September 1977 699 the month on the air

John Alloway, G3FKM

HE writer has received a copy of a letter from the TNigerian Ministry of Communications (Radio Services Branch) which quite clearly states that amateur licences are not being renewed until the state of emergency in Nigeria is lifted. This seems to indicate that only activity from 5N2NAS is officially approved and that other users of 5N2 calls are doing so without permission. Thus, an administration which could quite possibly support the amateur radio service in 1979 is being given the worst possible impression of radio amateurs. A sorry state of affairs indeed. Tim, BV2A BV2B, the only amateur on Taiwan DX News The Italian national radio society, ARI, will be celebrating its 50th anniversary during September. During the month the He has an FTIOIE and vfo and is likely to be active from special station IK5OARI will operate from Florence and will 2200 to 0200. Those looking for a 9U5 contact may try be active on all bands. It will be good for the "DGM" searching for 9U5CA in the 14,285-14,295kHz area after Award (see "Awards"). 2000, especially on Sundays. A group of Italian amateurs operated from San Pisto Is— G8KLB recently visited Tim, BV2A (see picture). He also off Italy in the S Adriatic Sea and said to be administered by holds the callsign BV2B and this is used for ssb contacts. He the Italian Navy. Their callsign was IJ7EX and the DXCC often operates from 2300 on Saturdays until 0200 on Sun- status of the islands is being investigated. days, and between 1100 and 1400 on Wednesdays, and The expedition to Palmyra Is and Kingman Reef seems to prefers 14,025, 14,040, 14,218 and 14,250kHz. The Taiwan have been a great success. In all, 16,150 contacts were made, government recognizes amateur radio, but at present no over 10,000 from Kingman: 2,900 of these were with Japan, facilities are provided for taking the required examination. 416 with Europe, 210 with C and S America, and 1,500 with Tim was licensed before the war and operates under limita- W6! Over 6,000 QS0s took place on 14MHz and the writer tions—he is confined to the frequencies mentioned. would like to join the many who consider this to have been V U2TN was heard by the writer to say that he hoped to one of the best operations for many years. visit VU4 during October or November—this is presumably WA6KWQ/KW6 is shore based and fairly active. C21EF the Laccadive Ls. No further details are available. is said to join in the SEANET activities on 14,320kHz from Ted Henry, W6UOU, and his wife (who is also licensed) 1200 quite often. set sail for a round-the-world cruise early in August. Their W1JFL reports mail difficulties between himself and first stop was to be in the E Caroline Is and then they were A51PN. It seems that he has logs for the period 18 August expected to go to E Malaysia, and afterwards across the 1972 to 16 September 1974 only, and that A51PN is not Indian Ocean to the Middle East and Africa. active just now and does not know when he will be back on DX News Sheet says that those who still need a QSL from the air. WIJFL also has logs and QSLs for Don Riebhors AC3PT should apply direct to him at The Palace, Gangtok, operations from CT4AT, XU1DX, C31ME and ZB2DM. Sikkim, India. S21AB has been reported to be crystal controlled on ZK1BA left the Cook Is early in August, and VRIX was 14,150, 14,195 and 14,250kHz, and to be heard after 1100. due to leave the Gilberts at the end of the month. The Phanh, XW8AL, is now living in Paris and is FODAJ. ZK1BA trip to Manihiki has been postponed. Other former Laotian amateurs are XW8FN who is now ZS2MI has been active and workable again—at around WB31DA, and XW8BS who is W7KRP. 1400 on 21MHz, and is also said to be on from 1300 at JTOOAQ made 5,500 contacts from Mongolia. He has now week-ends on 14,200, 14,300, 28,200 and 28,300kHz. returned to the USSR and is UC2LBI. Most QS0s were on HC8RG has been putting a good signal into Europe after 3-5 and 7MHz. UW3HY is said to be going to Franz Josef 2200 on 14,180kHz most Wednesdays. Land as chief radio operator and a result of this may be an Stations in Canada have been heard using CY prefixes in increase in activity of the only station on the island, place of their normal VE. This is believed to be celebrating UK I PAA. HM The Queen's Silver Jubilee. Prefixes in the AA series An American amateur connected with the USA Embassy came into normal usage in the USA from the end of July. in Douala may be on the air with a Ti call from mid-July. They will start to be issued in the 4th and 6th call areas where no more I x 2 calls are available for extra class • 10 Knighilow Road, Birmingham B17 8QB, licensees. Following this the series AB to AL will be used.

700 RADIO COMMUNICATION September 1977 "DX News Sheet" Geoff Watts' DX News Sheet has been published again since February, but for UK subscribers only. Geoff was ill until 31 January and can no longer cope with all the work involved in sending DXNS to over 1,000 overseas readers and in dealing with foreign money exchange. The only copies now going abroad are those sent in exchange for overseas dx bulletins. However, if an overseas amateur or listener wishes to receive DXNS it is suggested that he or she finds a friend in the UK willing'to forward the sheet each week, and to whom all payments must be made. It is not possible for these copies to be sent direct but they will be sent to the UK "agent" each Tuesday for forwarding. Your scribe has always recommended DX News Sheet for all those who are interested in activities on the hf/mf bands. It gives a great deal of information on addresses for QSLs, contests, dxpeditions, and activity by regular stations. A trial subscription (nine issues) costs £1, and other rates will be quoted on enquiry. Geoff's address is 62 Belmore Rd, Norwich NR7 OPU. The Prefix, Zone and Country List is also published by Geoff Watts-this is a complete listing of countries, prefixes, CQ and ITU zones, obsolete prefixes, USSR club stations, SE34CA (G3ANJ, A4XFC), Gordon Tho mas had just called CQ and other interesting facts. Its 15 pages cost 35p (inland) or Italy and was wondering which call to write down first hi! Gear, FT200 to a centre-fed long wire via an atu and balanced $1 or five mcs for overseas-no foreign cheques can be feeder. QTH Limassol Photo: CARS accepted.

QSL corner Any comments on the above should be forwarded to any In response to the plea in July "MOTA" for information on of the addresses given in the yl item on page 437 of the June the present whereabouts of former VS9 stations, a letter has Radio Communication, or by joining the yl nets on 3,710kHz been received from G3NAC (J. Hem, 45 Long Lane, Wil- at 1100 (Monday) or 1400 (Thursday). Support is needed and lingham, Cambs) concerning his operations from that part of interested ladies are invited to assemble in the tea room at the world. He still has his VS9AAA logs (he made 43,250 Granby Hall at 2pm on Saturday 29 October for a chat and QS0s!) as well as those for G3NAC/VS9, VS9HAA, cup of tea. VS9KAA, VS9AAA/VS90, VS9AAA/ZE, VS9HAA/ZE, VS9AAA/4W1 and VS9AAA/VS9M, and will confirm contacts appearing in these if details are given in g,mt and with The SE Asia Convention correct date. Incorrect times or dates will not be investigated. This year the convention will be held in Bangkok, and the Roger Wheeler, G3MG W, reports that he has lost contact Radio Amateur Society of Thailand invites overseas ama- with A4XGQ. He has thousands of cards for him but cannot teurs to attend. It will take place from 18 to 20 November, forward them as he has no current address. Those still need- at the Erawan Hotel, Bangkok. There will be an opening ing an A4XGQ card should send theirs to G3MGW, 26 luncheon, followed by lectures and an exhibition, and a Ladysmith Avenue, Brightlingsea, Essex, together with a grand banquet on the 19th. During the convention RAST sase. will arrange tours. Registration costs $25 and covers all Dalmo G. Pontual, PY6CN (PO Box 1351, Bahia 40.000, meals. For more details contact: SEANET 77 Contest Brazil), would like to contact the operator of the S Georgia Manager, Ismail Razak, 9M2FK, 281-C, Jalan Pekeliling, station VP8IE, active in 1968. Bukit Glugor, Penang, Malaysia. (G3FKM has a small quantity of information sheets.) BYLARA A meeting of yl operators/listeners was held at the 1977 Welcome Drayton Manor Rally with a view to forming a British The following joined the Society during July: EA1TA, Young Ladies Amateur Radio Association. Suggestions as F1CCP, F6A,JW, F6BQH, F6I3VD, F6DPH, I3KMR, to the need or purpose of such an organization would there- OZ27Y, SM6EUZ, VE3A0G, VE3R11, VK4HK, VK5Z1P, fore be welcomed. The following points are put forward as VK6WH, VP9IM, WA6GGH and WB9TDU. BYLARA's aims: (1) to further yl operating in the UK; (2) to promote friendship among fellow enthusiasts, (3) to Contests stimulate interest amongst YLS in amateur radio, and (4) to VK/ZL/Oceania Contest offer help in matters arising from or relating to yl interests. 1000 I October to 1000 2 October (phone) These objectives may be achieved by the following: (a) meet- 1000 8 October to 1000 9 October (cw) ings on the air, (b) meetings in person-at selected rallies, Exchange RS/T plus serial QS0 number (from 001). Con- (c) special representation to the RSGB on radio matters, tacts with VK or ZL count two points, with Oceania one (d) a special yl award, (e) a newsletter, and (f) the production point. Final score is total QS0 points multiplied by the sum of up-dated lists of yl operators. total of VK/ZL call areas worked on each band. Entries may

RADIO COMMUNICATION September 1977 701 be single- or multi-band. Logs should show date, time, QTH Corner station worked, band, number sent and received. Each new AIXVL via GISTP, 49 Broad Rd. Wickham Market. Woodbridge. call area worked should be underlined and a separate log Suffolk. submitted for each band. A summary sheet should be en- C31NB via F9AP. A. Pattelat, 29 Rue St Maur, 75011, Paris, France CGICR VEI ABM, 91 Harbourview Dr, Sydney, NS, BISSAS, Canada closed and should include name, address and callsign, FPOCJ via II8CJO, 3066 Grand View Dr, Allegan, Mich. 49010, USA. details of equipment used, and QS° points and multipliers FPODE via WB8NBT 220 Sanford Cl. Zeeland, Mich. 49464, USA. IJ7EX I7VCA. PO Box 1, 1-70100 Bari, Italy. for each band. A signed declaration that all rules have been KG6RE Via JAVILT, Y. Maruyama, 204 Gonaka, Shinozuka, KOzaki, observed should be included. Listeners may enter and only Hoigun, Alchl 441-01, Japan. KA M vie /CA WS, USA CC-J, SSA-S. Commend Radio Stn, APO, VK and ZL stations should be logged-date, time, call, San Francisco, 96331, USA. station being worked, RS/T of the VK/ZL, serial number W ASK WDrK W6 AI Gordon, 3222 Hill St, San Diego. Cal, 92106 . USA. TFIF Box 1058, Reykjavik. Iceland. being sent, band, and points claimed should be noted. VPSW W via W614EYX. 1730 Woodmere Drive, Jacksonville. Fla, Scoring is otherwise the same. Logs should reach WIA Con- 32210, USA. VP2MVP via WEMCSK, 1839 Dunroamin Lane, Fayetteville, Tenn. test Manager, GPO Box 1002, Perth. 6001, W Australia, no 37334, USA. later than 31 January 1978. ex-Y.111AN ZLIBNE, R. Boole, PO Box 71, Kawerau, New Zealand. ZM7AT via WB6DXL. W. Ellison, 16630 Lawnwood, Vallnde, Col, 91744, USA. The CQ WW DX Contests ZMINIM vie W6FWX, Dick Alfaro, 1812 Webster SI, San Francisco, Cal, 94115, USA. 0000 29 October to 2400 30 October (phone) 3V1113Z now via DL1HH, H. Groh, an Der Bohn 5, 6236 Eschborn. 0000 26 November to 2400 27 November (cw) Niederhoechstadl. W. Germany. ex-5N2AAU W. Senior, Birkenau, Bundarra Rd. Armidale. NSW 2350. All bands 1.8 to 28M Hz. Exchanges consist of RS/T and CQ Australia. zone number (UK is in zone 14). One point is gained for SWIBE via KS6DV, L. A. Gandy, C8 82, Pago Page. 96799. American SWIDF Samoa. contacts with one's own continent and three with others. Only multiplier credit may be claimed for contacts with one's RSGB QSL Bureau, G2MI, Bromley, Kent, BR2 7NH own country. The multiplier is the total number of DXCC and DARC countries, plus zones, worked on each band added together. There are three categories of entrant: (a) single-operator single- or multi-band, (b) multi-operator, mode, or mixed. The areas to be contacted are as follows: single transmitter (all band), and (c) multi-operator, multi- D4. Lisbon, CT3, CN8, Cadiz, El, F, FC, London, Flatholm transmitter. In category (c) several transmitters may operate Is, Isle of Wight, GI, GM. HB, HV. Bologna (14), 15, Rome simultaneously, but only one signal may be radiated on each (10), Sicily, Sardinia, JA, Buenos Aires, ON, Rio de Janeiro, band. Entrants should use separate log sheets for each band Stockholm, Gotland (SM1), Leningrad, VEI, VOI, V02, and follow the layout of the official form with 40 QS0s per Sydney, VP9, Massachusets, NY/NJ, Missouri, Illinois, VU, sheet. Log and summary sheets may be obtained from CQ ZB2, YU2, and Tripoli (5A). 1I4FG M and IP1TTM are by sending a large self-addressed envelope and !RCS to special stations. IK5OARI will be active during September CQ W W DX Contest Committee, 14 Vanderventer Av, and will also count. All contacts must have been made since Port Washington, LI, NY, 11050, USA. This is also the 1 January 1973, and applicants should send a list of QSLs address to which entries should be sent; they should be post- held (certified by an IARU society awards manager) plus log marked before I December for the phone section and before details and return postage to: ARE. V. Scarlatti 31, Milano, 15 January for the cw. Italy.

Results of the 1977 WAB LF Phone contest have arrived The Certificato del Mediterraneo (CD M) from GM4ELV. In the single operator section scores were Also issued by ARI. For confirmed contacts (since 1 June as follows: G3DDK (263.070), G4BWP (241,995), G4FQ0 1952) with a fixed station in at least 22 countries on the list (240,980), G3W WX (141,810), G3VVE (132,345), G3XFW plus 50 stations in peninsular Italy. It is issued in mixed or phone classes. The countries list is: EA, EA6, EA9, CN8, F. (68.365), G3YOL (53,560), GW4DKZ (43,170), G4AVA 7X, FC, IS, IT, OD, SU, SV, SV (Dodecanese), SV (39.600), G3JZP (37,410), GW4CM W (35,640), G4BLR (21,440), GM4DZX (18,600), G3EJF (12,750), G3JVU (Crete), SY (Mt. Athos), TA. YK, YU, ZA, 9H. ZB2, 5B4, 3A2, 3V8, 4X4 and 5A. Send certified list (as for DGM) (12,250) and G3ILO (3,750). G4AVA/M (2,695) and G W4CM W/M (2,205) entered the mobile section, and plus log details and 10 IRCs to: ARI HF Awards Manager G3OUR (106,735) and G30MT/P (57,165) the multi- I8KDB, G. Nucciotti, Via Francanzano 31. 80127 Napoli, operator section. G3ABG scored 2,415 on 1.8MHz and Italy. G3FKM has a small supply of leaflets describing ARI G3OUR (1,125) on the same band as multi-operator. The latter was also the only 7MHz multi-operator entry. Lis- awards. Please send sase. teners were BRS29330 (176,910), Susan Coombes (166,505), BRS38225 (146,850), BRS35509 (123,670) and Ian Lumb Official Bulletin No 660 from ARRL included the informa- (58.780). tion that the proposal to start DXCC from scratch again in 1980 was rejected at the board meeting in July. From another source news has been received that a special satellite Awards DXCC will be available from 1 October. It will not have The Diploma Guglielmo Marconi endorsements. Issued by the ARI free of charge to those who have contacted (or listened to) the localities where Marconi worked. The Worked AB Britain Award Forty QSLs (or 35 plus one from the official commemorative Please note that from 7 June 1977 the sales of WAB books station II4FG M and one from any other G Marconi Mem- has been taken over by Mrs J. E. Lacey, Oak Tree Bungalow. orial station) must be held. The DGM can be endorsed for Lambourn Woodlands, Newbury, Berks RG15 7TR.

702 RADIO COMMUNICATION September 1977 Band reports 14MHz SEPTEMBER 1977 At the time of writing, conditions on the hf bands had USA-East W1-4 S

deteriorated slightly and a fairly long series of "low normal" USA-West W6,7 S I l , days was forecast. The Zurich observatory reported the Caribbean 6Y5,FM,T I S ,012Z1=1 CI:2M M = mean sunspot count for June as 38.4—in June 1976 this was Brazil PV S ref-4u . lob 12.4; lowest days were only eight but the highest (the 25th, South Africa ZS S 3 ; 26th and 27th) reached the seventies. The Russian inter- SE Asia HS, 9M2 s : : ,CE=IIIM mlizr=3 ference has continued in spite of official complaint and is 1 ; 1 rzazzt.,,e« Australia VK S : 1, beginning to cause some to think that action should be taken L ¡ to "black" Russian amateur activities. Japan JA S i ,IZEZ =1=n Once again many thanks to those who sent in items for Time (GMT) 00 2 04 06 08 lb 12 14. 15 20 222224 24 this month's column, and to the following for supplying information for this section: G2HKU, G4RZ, GSM., G6GH. 21MHz SEPTEMBER 1977 , 1 G M3LYY, G3RCA, G3RZf, G4DSE, G4EAN. G4EHQ USA•East W1 -4 S r -zer .1 and A8961. USA-West W6,7 s , Caribbean 6Y5,FM,Te S i I .•••••••z•z/2• ,•,./A • I 7MHz. 0500 CO, CX, FO8AP,F08EX, KS6FFIHR3 (QSL WB6DXL), Brave PT S ; JA8U111,q, WEMEMAITG, IL2-21.4, ZS1HF. 0600 CE, W6, VK, IL, 4M7PF. South Africa ZS S , or- wee"; ." ..00 14MHz. 0200 KB3BSF (QSL W3EEK). 0500 KL7IIP. 0600 FOBET, SE Asia HS,9M2 S C. ,...• Z. (2 /27,'".1 i W6/1/V7, VR6TC, ZK1DR. 0700 K1DRIWC6A, FO8EX. 0800 KH6, Australia V K S ; ; 1‘eria e KS6DV, KX6BU, ZL, 3V8BZ (QSL to DL1HH). 5W1s AU, BE, BE. 0900 KH6DL (ex-KJ6DL), ZM7AT. 1000 H M2JN (QSL JA1HBC), Japan JA s ' t VR4BT, ZM7MM, 3D2RM. 1300 HS1WR. 1400 SP2EFU,V W, XT2A E. Time (O w l) T) 00 02 04 0608 10 12 14 16 19 20 22 24 1600 3B8DL. 1700 LZ1CY;02 (QSL LZ Bureau), TR8LE. 1800 J28A0. 1900 TU4FOC, VP8ML (QSL W4M WT). 2000 W4YHK VQ9, 5Z4WL Short path 11- 5days • 12 =226-20days (QSL DL3WL). 2100 C5AAD (OSL via G2M1), WB5LBJ DU (QSL to K7LAY), VP5MA (QSL to WB4LFM). 2200 FMOBZK (QSL to FY7AS), LOng path openings on more than 20days in the month FMODON, XP1AB, IL4NH. 2300 H13MOG (W31-INK). VP1WS, VS6BE. 21MHz, 0800 EP, JA, ZS. 1100 A9XV. 1400 ZS2MI. 1700 A4XFZ, EL2EU, VP2IVIBB, 5Z4HZ, 9G1JX. 28M Hz—Occasional Europeans. DX News Sheet notes that HF PROPAGATION STUDY G4DY0 has now contacted 115 countries on the band during 1977. Predicted HPFS (MH: ... 10) for September 1977 Acknowledgements to the authors of the following for G MT - 00 02 04 06 08 10 12 14 16 18 20 22 24 items obtained from their publications: DX News Sheet Aden 147 130 143 232 268 286 286 291 303 238 190 155 147 Ascension 161 154 144 130 251 284 291 301 310 323 280 182 161 (Geoff Watts), the 29 DX Club Bulletin (VK6RV), Long Skip Bahrain 139 124 147 221 260 272 272 272 260 234 181 148 139 (VEIAL/3), The West Coast DX Bulletin (WA6AUD). Bangkok 120 112 153 204 235 246 248 246 210 190 169 139 120 Barbados 150 128 126 119 152 233 253 253 251 257 251 213 150 DX'press (PAOTO), CQ Magazine (W1WY), the Ex-G Beimuda 144 117 117 114 117 205 234 238 233 234 235 208 144 Radio Chtb Bulletin (W3HQ0), and RSZ Newsletter Boggle 147 125 121 116 144 174 251 247 246 248 247 214 147 Buenos Aires 153 143 138 134 150 257 276 276 276 293 277 204 153 (9J2KL). Cape Town 154 144 130 206 270 290 298 305 322 314 247 178 154 Please send all items for October issue to reach G3FKM Colombo 130 121 154 218 255 265 266 263 261 227 187 144 130 Cyprus 130 117 126 196 235 255 262 252 260 247 188 140 130 no later than 9 September, and for November by 8 October. Dakar 149 139 131 149 235 275 282 289 289 310 274 182 149 Denver 136 115 106 103 112 111 155 188 205 213 202 173 136 Fairbanks 133 121 116 130 150 150 158 161 171 171 169 140 133 Falklands 157 144 139 139 145 256 277 281 286 304 276 197 157 GH oibnr:kllae r,ro 94 87 83 105 148 174 176 173 174 176 158 112 94 Honolulu 114 111 148 194 221 232 235 197 178 164 152 136 114 Propagation predictions 133 116 110 115 183 141 133 126 154 195 178 145 133 Iceland 91 79 79 89 130 147 157 157 153 154 140 105 91 Jamaica 147 122 119 114 143 164 234 238 234 237 234 206 147 Lagos 162 154 136 188 263 289 296 305 322 328 257 178 162 Propagation conditions in both the northern and southern hemi- Las Palmas 141 128 121 131 202 243 248 244 247 258 233 166 141 Lima spheres are about even during September. At the same time Los Angeles 154 133 130 122 155 168 262 256 257 263 257 213 154 seasonal changes mean that slow improvements will occur In dx 136 115 106 103 119 111 114 177 204 208 195 187 136 conditions on the ht bands, to reach their maximum during October Mann 108 98 98 147 183 208 208 205 210 208 172 120 108 Mauritius 152 134 140 235 27/ 290 295 301 309 284 218 159 152 and November. As solar activity is now increasing in the 11-year Mexico 140 114 102 106 145 130 185 219 219 224 213 186 140 cycle of sunspot activity, the 28MHz band will be open to traffic Moscow 98 93 93 155 180 194 202 200 200 194 149 119 98 with South America from about 1500 to 1930gmt and with Africa Nairobi 154 138 139 225 272 291 293 301 314 296 224 163 154 from about 1000 to 1900gmt towards the end of the month. Traffic New Deihl 122 116 155 210 243 252 255 251 232 185 155 140 122 with Central America, South-east Asia and Australia on 21MHz New York 141 119 114 111 Ill 173 205 221 223 225 216 190 141 will improve slightly. Short skip conditions will tend to cease Osaka 114 111 128 180 200 211 201 171 145 140 138 136 114 Perth 131 121 154 218 253 263 235 204 188 166 150 144 131 towards the end of the month. Rio de Janeiro 158 144 140 136 183 268 277 280 277 290 277 202 158 Longer nights and the coming of autumn mean almost no dx SeychellesSalisbury 158 144 136 219 275 295 298 307 324 308 234 169 158 during the latter halt of the night on 14MHz. For this reason 7MHz 154 133 141 235 267 280 282 293 307 280 211 152 154 will become the main carrier of dx during this period. Contacts on SuvaSingapore (s) 122 116 155 210 243 252 255 251 251 232 176 136 122 this band and on 3.5MHz will be possible when the greater part of Suva Cl) . 124 115 114 158 187 195 202 192 152 177 144 135 124 the path lies in darkness: this is most important for 3-5MHz. Longer Sydney (s) 152 159 139 180 187 163 153 150 121 161 244 185 152 nights and the decline of static will improve dx on 7 and 3•5MHz. 114 111 148 194 221 232 200 187 177 147 148 1313 114 Sydney (I) 152 133 13e 122 159 135 125 120 117 120 187 209 152 Local traffic will be interrupted by the dead zone at various times Teheran 133 121 154 2113 255 265 266 263 271 237 1(30 144 133 in the latter half of the night. Vancouver 134 119 111 111 129 125 126 153 161 176 185 155 134 The provisional sunspot number for July 1977 from the Swiss Wellington (s) 114 111 122 178 195 194 192 173 159 143 143 126 114 Federal Observatory was 21.2. Sunspot activity was largely con- Wellington (i) 149 147 139 143 143 124 110 110 111 158 194 192 149 centrated in the first and last weeks of the month. The predicted For informelion on the use of this table, see page 284, Radio Communication April smoothed numbers for November, December and January 1978 1976. Please send reports lo Mr .1. Spurling. G4A01, 15 Tibbs Hill Road, Abbots are 29, 31 and 3.3 respectively. Langley, Watford, Herts WD5 08E.

RADIO COMMUNICATION September 1977 703 Mr J. Partington, G5PX Nominations for election to Jack Partington died on 9 July aged 80 years. He was well known in the Lancashire and Cheshire area for his activity on 160m, and the 1978 RSGB Council among oft operators and SWLs. Mr W. H. Segrott, G8SI Bill Segrott died on 17 July. He was active over many years and had a wide circle of friends in the amateur radio field. The Articles of Association require that not later than 10 September in each year the Council will send to each member entitled to vote Mr R. Silverthorne, GW2BG a list of those Council members who retire by rotation or for any Reg Silverthorne died on 24 July. He had been licensed since the other reason on the succeeding 31 December. The list must indicate days of the 1,000 and 400m bands, and operated on all bands until those members who are willing to accept nomination for re-election just before his death, He was particularly well known on 3.5MHz. and the list must also indicate whether the vacancies are to be filled In public life he was twice Mayor of Abergavenny. by election of an ordinary member or on a zonal basis. The following members retire at the end of this year: Mr F. WaIklett, G8AV W Fred Walklett died on 16 April aged 55. He was well known in the Ordinary members Lancashire area and further afield although active only on vhf. Dr E. J. Allaway, G3FKM, (by rotation) who will accept nomination for re-election. Mr W. Wardrop, G3M O W Mr D. M. Pratt, G3KEP, (by rotation) who will accept nomination "Wally" Wardrop died at the end of last year and has been greatly for re-election. missed by the wide circle of friends he gathered around him on ht bands. Zone E member Mr D. M. Thomas, GW3R WX, who does not wish to be nominated We have also been advised of the deaths of: at this time. Mr A. A. Bain, GW5KK, on 9 July: Mr R. C. Harris, G2BAB, on 8 July. Not later than 10 October next any 10 corporate members may nominate any qualified member to fill one of the above vacancies, by delivering in one closed envelope to the secretary of RSGB, their respective nominations in writing together with the written consent of such member to accept office if elected. Each such nominator shall be entitled to nominate only one member for election. In the same envelope, nominees should include brief biograph- ical details of themselves for publication in Radio Communication at your opinion the time the election is held.

QSL BUREAU The Editor Radio Communication Sir— What a collection of selfish, parsimonious misanthropists obituaries there are in the world, and in our Society in particular. G8WS has already been soundly dealt with except on one point which I would like to mention later, and now we have "times are hard" G3KTL. The November 1976 Balance Sheet shows a total expenditure of £120,520. The only item which specifically mentions cost of QSL The Society records with regret the deaths of the following radio Bureau also includes Beacons and Intruder Watch. The sum amateurs: against these items for 1975-6 is £1,868. If we count all this sum as QSL Bureau it is 1.5 per cent of expenditure. As a part of the £8 Mr J. C. Ayling, G3PN A annual subscription 1-5 per cent is—wait for it-12p. To forestall John Ayling died on 22 May aged 62. He was a keen vhf and iP possible (incorrect) objection, if it is taken as a percentage of operator, and an active member of the Reigate ATS since 1959. He subscription income, £87,956, the percentage is two per cent, or 16p was awarded the Norman Keith Adams prize in 1963 for his article per annum. on hydraulic masts for portable use. So we all contribute about 1p per month to finance a first-class QSL Bureau and, since reading G3KTL's letter fiercely objecting to Mr R. G. Day, G3Z WX paying this sum on the grounds of hardship, I cry myself to sleep Gordon Day died on 20 June at the age of 58. He was a keen sup- every night. So touched am 1 by his desperate poverty that I am porter of Wakefield DRS and a stalwart com mittee member. prepared to raise my subscription to £8.12 to relieve him of his distress and give myself a quiet night's sleep—and 1 have been, Mr H. Ford, G30 MG from the Government's viewpoint, unemployed for the past year. Henry Ford died on 10 June aged 64. He was a founder member of He says QSLs are now largely a "fun thing". So when we, before the South Birmingham RS, its chairman for many years, and the the war, received a card for a contact or report, we got no "fun" out first member to be given a life membership. He was active on 20, of it ? QSLs have always been a "fun thing" and G2M1 and his many 80 and 160m. helpers, the sub-managers, have been spreading "fun" for many years and I, for one, am very grateful. Mr E. P. Inman, G2DRA Now to G8WS. I never fail to hear him on 20m long path any Ted Inman died on 15 July at the age of 68. He had held a licence since 1932 and remained active until just before his death. He was a morning he is on. Often I hear him when, after I have called a station, I find it has gone back to G8WS. Hitherto I have philosophically member of the VHF Century Club. shrugged my shoulders and envied his luck. 1 find 1 have been Mr W. R. Lawrence, G3PDS mistaken. His ability to get any station available gives him no joy. William Lawrence died on 12 April. He was a founder member of He knows he can work them easily (his words). Therefore he says of the South Birmingham RS and its treasurer for many years. He he has no need of QSLs and does not see why those who do should was also a member of the Midland ARS. He was well known on top not pay extra for what he has not had to pay for in the past and has band. no desire to pay for in future. I, on the other hand, the inevitable loser In any radiation contest Mr C. B. Pretty, G3BND with G8WS or any other beam station, have, at the age of 62, never Bernard Pretty died on 29 July. He was licensed in the early post- yet lost my sense of wonder at being able to talk over long distances. war period and at one time was a keen constructor. His recent My "garden" is L-shaped with leg of 1211 A Mosley V3Jr stands interest was vhf fm. on the ground no more than 411 from the nearest brickwork. No

704 RADIO COM MUNICATION September 1977 radials are really possible—none at all on the south side of the vertical. Yet my Great Circle map on the wall behind me has pin- THEY MET AT identified contacts in all parts of the world with those "fun" QSLs to prove it. The majority long path. I never cease to be astonished. My praise and warm regards go to W6UA, whose exposition of THE PALACE the true "ham spirit" cannot be bettered. Others have put on record for all time (I assume the Society fulfils its statutary obligation to the national libraries) that they strongly deplore the possibility that a minute fraction of their subscription might benefit other members and not them. By the same post as this letter I sent a QSL air mail to a listener in Tokyo In reply to a report I did not need received via G2MI. The reason? The printed wording on his very plain card was original and amused me. It gave me added pleasure to provide him with a pleasant surprise. No doubt some would find such behaviour quite incomprehen- sible, but Charley Wein will understand and so, it seems, will the Mayor of Haringey. As Charley says, "Its what amateur radio Is all about". B. R. Meredith, G2CYV ORIGIN OF FM The Editor Radio Communication Sir— World al their fingertips, chapter 23, p166: "In June 1935 the Society published what was probably the first technical description in the United Kingdom of Frequency Modulation". I have one of Cassell's "Work" handbooks titled Wireless Tele- graphy and Telephony in which a previous owner's signature appears dated 1925. Chapter 11, p139: "Present methods of attaining the desired object" (ie modulation) "require that a wireless transmitter capable of radiating electro-magnetic waves of constant wave- Peter Balestrini, G3BPT, RSGB Emergency Com munication length and amplitude be employed at the sending station, and that Manager (left) in conversation with Max Halphen, F8TH, either the wavelength or amplitude (or both) of the emitted waves manager of AURA REFPC, au service de la protection civile, be varied at audible frequency by the current changes through a suitably connected microphone". on the Raynet stand at the Alexandra Palace Exhibition This appears to refer to fm of some kind, and it seems improbable that some technical information on how to achieve fm had not been published before 1925 at the latest, and quite possibly in the UK. Can any RSGB members throw more light on this question. And for the sake or stirring it in W-land, perhaps Armstrong was not the "inventor" of fm. Hugh H. Oak-Rhind, G2AUD REVERSE TVI The Editor Radio Communication Sir—As a follow-up to the letter from G3KRC about tv licences ("Your opinion", February), may I draw readers' attention to para- graph three of the normal television broadcast receiving licence? It reads: "The apparatus shall be so maintained and used that it does not cause undue interference with any other wireless tele- graphy". Could this be of help to fellow amateurs who have problems with tv time-base radiation. R. Brothwell, G4EAN

Les Hawkyard, G5HD, VHF Contests Com mittee secretary Special event stations (left) talking to Lyall Herdman, GP M, Contest Com mittee secretary a decade ago, at the Alexandra Palace Exhibition

10 September, National Scout Camp The Sutton & Cheam RS will be operating an exhibition station at "Walton Firs" National Scout Camp. Cobham, Surrey, from 10 am to 5pm. Callsigns G3DCZ/A. G4A DM/A and G4BOX/A will cover 80, 20/15 and 2m. Over 1,500 Cub Scouts will be at the camp, and contacts with all stations, particularly those with Scouting connections, will be welcome. 17/18 September, Southlands Arts Festival The Civil Aviation Authority RS will operate a station at the South- Give for those who Gave lands Arts Festival, The Green, West Drayton. Middlesex. using G4CAA/P. Talk-in on 2m and 70cm. and a demonstration of fast- scan tv. 18 September, Chichester & D ARC WINGS APPEAL The Chichester & D ARC will be active from the QTH of the late e Gerry Marcuse and will especially welcome contacts with old- 1;<,{ timers. Callsigns G2NM on 80m and G3ISO on 2m. Details from k4c, ete G4ETU, tel 0243 88069. 25 September, Bulmers Railway Centre During Septe mber The British Rail ARS will be operational on the last of the open days at the steam depot, Whitecross Road, Hereford, using the callsign G3SC W/A.

RADIO COMMUNICATION September 1977 705 NATIONAL FIELD DAY 1977 RESULTS

"Amazing", "Fantastic", "Wonderful", "Best yet", are typical of the many com ments received this year about propagation conditions NF D Trophy and the record scores achieved by entrants in both the Open and Channel Contest Group 3,356 points Restricted sections. Although certain parts of the UK suffered from the weather, the really excellent conditions on all the ht bands seem to have provided compensation for the torrential rainfall and flood- Gravesend Trophy and ing reported by many groups. Scottish NF D Trophy While a few entrants still regret the demise of the two-station Glenrothes & District ARC 2,803 points low-power event, the majority have clearly Indicated that they like the present rules and prefer the use of licensed power. There were one or two adverse comments about the decision to allow the use Bristol Trophy of the GE prefix as it was felt this gave an unfair advantage to the Swansea ARS 2,570 points less common GE2, GE5. 6E6 and GE8 entrants and to the Broms- grove group who sponsored a special certificate for working their Frank Hoosen (G3YF) Me morial Trophy club stations and other GEs. The use of the GE prefix was open to all groups, but only 42 of the 93 total entrants used It In the contest. Telford & District ARS 1,953 points Judging by the overall results in both sections, it seems doubtful if the use of the GE prefix provided any real advantage. Leading scores on individual bands

Open section 1.8MHz Gloucester ARS 430 points The 1976 battle for top honours between the Glenrothes & DARC 3.5MHz Shefford & D RS 720 points and the Channel Contest Group was again joined In NFD 1977. Last 7MHz Edgware á D RS —"A" 1,070 points year. Glenrothes took first place with Channel as runners-up, but 14MHz Telford & D ARS 1,953 points this time, the position Is reversed with Channel. GE4D AA/P, lead- 21MHz Glenrothes & D ARC 568 points ing the field with a record number of QS0s and points. They used 28MHz Swansea ARS 682 points a Drake 4C combination with a separate SB-301 receiver, a three- band cubical quad at 60ft and separate dipoles at the same height. Analysis of their logs shows that their operators, G3FXB and Overseas station giving most points to entrants G3MXJ, achieved the record average of 40 plus contacts per hour Leonard Snowdon (9HICH) 900 points for the duration of the contest and at peak times they exceeded 55 per hour. Their 970 contacts and 3,356 points win them the NFD Shield. Glenrothes, GM3YOR, operated by GM3OLK, GM3YOR, GM3ZSP and GM4ALK. made 806 contacts (average 33-5 per hour). As there between 70 and 300ft, centre-fed 132-138ft multi-band wires open- are a greater number of entrants in the Open section than in the wire led, 138ft off-centre fed wires, trap verticals, loops, 35ft base- Restricted, they receive the Gravesend Trophy, and being the fed verticals and other odd-ball "secret weapons" that clearly did highest GM entrant, they also receive the Scottish NFD Trophy not work as well as expected by their designers. What is a single- together with the certificate for 21MHz. Glenrothes used an FT1018 element echelon ? transceiver, a TH -3 triband Vagi and separate dipoles for the three If bands. Scottish NFD Trophy The 1976 winners of the Restricted section, the Racal AR Group, As noted earlier, the winners are the Glenrothes ARC, with the G3RACIP, with 660 contacts, changed sections this year and are Kingsway Technical College, Dundee, GM4A AF/P, as runners-up. placed third. They also used an FT101B transceiver with a quad, lazy-H and dipoles. 113MHz In a year when conditions on the higher frequencies were so good, Restricted section the attention paid to top band might be expected to be less than The excellent band conditions also helped the leaders In the usual. However, the Gloucester ARS, G3MA/P, spent 64 hours on Restricted section to achieve record scores. The Swansea ARS, the band and made 84 contacts, 56 of them being with the 65 groups G W5ZLIP, third in 1976, are this year's winners of the Bristol claiming points on 1.8MHz. They used a mixer vfo-ba-2E26 pa trans- Trophy. Using a modified FT101B fort.8MHz and an FTDX500 for the mitter and a Marconi-tuned trap dipole. Operators were G3MA, other bands, with a 264ft multiband doublet (feed method un- G3XMM, G4CSC, G4FMN and G5BM. specified), team. GW3GLY, GW3IN W, GW30AY and G W3NJ W, Groups less dedicated to the medium frequencies spent two made a total of 688 contacts. hours on the band making 250-300 points. At that rate of scoring the In second place are Croydon:SRCC, GE6LXIP, who also changed band is good value and it is surprising that several groups omitted sections this year. Their operators, G3BFP, G3IAS, G3JLB and its use entirely. G6LX, worked 586 stations. Croydon used a 138ft wire, fed off-centre with open line, and an FT101B transceiver. 3.5M Hz The Northern Contest Group, GE3VM W/P, took third place from The greatly improved hf band conditions this year are reflected in 588 contacts. They used a FT101E transceiver and a 2081t aerial the lower scores on 3.5MHz. As will be seen from the overall centre fed with open wire feeders 30ft high. tabulation, many of the leading groups, especially in the Open As will be seen from the breakdown of QS0s per band, the leaders section. were able to almost dispense with operation on this band. made good use of 28MHz. Their results will confound those who The band leader this year is Shefford & DRS, GE3FJE/P. which consider that a high-gain beam is a pre-requisite for successful operated exclusively on this band, making 301 contacts. Operators 28MHz operation. were G2DPQ, G3DOT and G4B WP. In second place are Bury Radio Many entrants in the Restricted section have asked that the report Society, G3BRS/P, who made 270 contacts. includes greater information about the aerials that were used. This Favourite aerials were dipoles among the Open section entrants presents a problem, as many groups have not disclosed the feed and longer wires fed with open-wire line among the Restricted method used, and in some cases the exact length of the wire. By section. As usual there was a good supply of European portable checking the inspection reports and by a certain amount of detec- stations workable during most of the contest period from the tive work, it seems that 11 groups used centre-fed wires in the 260- majority of UK areas. There was a sprinkling of east coast USA in 270ft range, either as horizontal aerials or as inverted-Vs. The next the early hours of the morning and a few of the sharper-eared popular aerial was the trap dipole based on the 3.5-28MHz W3DZZ were rewarded with some six-point ZL contacts around 0530. design and fed as a Tee for 1 -8MHz. Of the nine groups that used this design, three were mounted as inverted-Vs, the others being 7MHz horizontal. The G5RV was also very popular, either as a 102ft or a Some very high scores were achieved on the band and contacts double-sized 202ft version. with VK, ZL, JA, W and VE were included in over half the logs. The remaining entrants used end-fed wires that varied In length Many of the leading stations obtained extra points by working the

706 RADIO COM MUNICATION September 1977 OPEN SECTION Number of Posn Group Callsign 1.8MHz 3 5MHz 7MHz 14MHz 21MHz 28MHz Total contacts 1 Channel Contest GO GE4DAA/P 184 61 413 1.819 293 586 3,356 970 2 Glenrothes & D ARC-"A" GM3YOR1P 258 132 543 1,008 568 294 2,803 806 3 Racal AR Gp G3RACIP 332 199 469 726 309 444 2,479 660 4 Guildford & D RS-"A'• GE6GSIP 266 218 426 619 262 410 2,201 622 5 Cornish RAC GE4CRC.P 208 121 119 820 364 558 2,190 587 6 Bromsgrove 6 ID ARC GE3VGG,P 266 144 127 1,044 279 320 2,182 608 7 Medway RC Gp G3ZYV'P 162 205 450 828 173 324 2,142 602 8 Torbay ARS-"A" GE3NJA.P 248 149 250 882 433 176 2,138 612 9 Bracknell ARC GIBRA P 374 457 509 524 119 104 2.087 604 10 Leyland Hundred ARO GE3GGS, P 336 134 422 488 262 434 2,076 529 11 Bristol Contest GP GE5YEI P 186 330 437 695 120 309 2.068 594 12 Addiscombe ARC GE4ALE,P 234 343 439 663 224 118 2,021 608 13 Maidstone YMCA ARS GE3TRFJP 352 218 439 827 59 103 1.995 596 14 Reading ARC GE3ULT1P 290 339 423 542 155 206 1,955 550 15 Telford 60 ARS GE3ZMEiP o o 0 1,953 0 o 1,953 640 16 Hereford ARS GE3YDD1P o o 0 1.861 0 0 1.861 583 17 Norfolk ARC GE4ARN.P 236 341 336 581 171 116 1,781 570 18 Mansfield RS G3GQC/P 0 265 293 1,137 54 28 1,777 579 19 Kingsway Tech Coll, Dundee GM4AAF!P 196 329 205 433 337 200 1,740 432 20 Verulam ARC G3VER1P 162 332 672 330 76 146 1,718 530 21 Oxford University RS G3OUR,P 282 112 612 469 87 104 1,666 478 22 N W Kent Contest Gp GE3XRX1P 270 285 232 681 149 42 1,659 466 23 Horsham ARC GE3TNO,P 226 260 473 533 121 24 1,637 508 24 Hull & D ARS GE3AM W.P o 454 420 694 49 o 1,617 559 25 Greenock & D ARC GM3ZRC P 76 161 149 608 232 370 1,596 426 26 Leicester RS G URS P 234 402 284 436 115 54 1,525 44.3, 27 "The Hamsters" GM3SSB,P 0 147 325 462 159 424 1,517 401 28 Chelmsford ARS G3WSP411. 162 177 382 476 156 140 1,493 439 29 Crystal Palace 60 RC G3VCP P 342 211 210 404 172 152 1,491 410 30 Bangor & ARS G13)(RO1P 244 118 199 440 185 298 1,484 418 31 Catterick Garrison ARC G3CID2P 288 291 280 138 184 202 1,385 370 32 Grimsby ARS G3CNXIP 340 222 217 223 220 o 1,222 350 33 Scarborough ARS GE413P P 222 167 113 378 193 136 1,209 327 34 Colchester RA G4CRA!P 316 443 289 69 23 12 1,152 331 35 Ilford RSGB Gp GE3XRT ,P 260 342 235 311 o 0 1,148 357 36 Ayrshire ARO GM3 WIL/P 16 78 313 319 143 96 1,111 313 37 Edgware & D RS-"A" G3ASR/P o 1.070 0 o o 1.070 339 38 Edgware & D RS-"B" G3GC P 27 267 0 220 223 18 1,002 277 39 {Dundee RSGB Gp GM3NHQ P 13 424 352 194 0 983 298 Farnborough & D RS-"A" G3RRAiP o 983 o 0 0 983 308 41 Southdown ARS G3WOKiP 318 196 313 14 56 897 290 42 Bury RS G3BRS/P 21 647 0 0 0 0 855 309 43 Worthing & 0 ARC GE3 WOR/P 120 247 331 53 0 751 249 44 Easinglon & Hartlepool ARC GE4APN!P iits 354 112 74 50 738 259 45 Sheflord á 0 RS GE3FJE1P 720 o o 0 0 720 301 46 West Kent ARS GE3WKS!P 70 297 256 41 8 672 214 47 Maidenhead & D ARC G3WKX/P 597 o o o 0 597 229 48 Thornton Cleyeleys ARS G4ATH'P 44 19 289 113 22 487 155 49 ClitIon Battery Wireless Club G3JKY P 402 o 0 0 0 402 t 55

African, Middle East and Bermuda portables, which were readily Second place is taken by another single-band entry, that of the available during the night. Hereford ARS, GE3YDD'P; operators G3HV X, G3WRA and The band leader was the single-band entry from the Edgware á G4CNY employed an FT101B and a two-element quad. DRS "A" station, G3ASR1P, who made 339 contacts, a substantial increase over the 1976 band leaders' total. The operators were 21MHz G3V W, G3GC and G3SJE and they used a T4XB.R4C combination With 14MHz open for virtually the whole period of the contest and working into a V-beam 461t high. with double points available from 28MHz, entrants had to decide Runners-up on the band were the Farnborough á D "A" station, how much time to spend on 21MHz. Many groups gave it short shift, G3RRAIP, who were also a single-band entry. They used an FT- or used It as a fill-in between sessions on the other bands. These 101 Et transceiver and a Delta-loop aerial to make 308 contacts; may have been wrong tactics, as those who used the band found operators were G3RRA, G3SVL, G3SZG, G3TMQ and G3VAA. In that conditions were generally good with world-wide dc and Euro- third place is the multi-band entry from the Verulam group, G3VER P.' pean portables workable at a rapid pace for long periods during the All three band leaders entered the Open section of the contest to daylight and evening hours. avoid the limitations of a single simple aerial at a lower height. As part of their eflort to make a high overall score in the Open section, Glenrothes "A" used the band to good purpose and made 14M Hz 178 contacts. In second place, the Torbay "A" station, GE3NJA;P, Conditions can only be described as superb, with the band open made 128 contacts. Both Glenrothes and Torbay used TH3 tri -band for (ix for most of the contest period. Vagi beam antennas and transceivers. Some excellent short skip into Europe, particularly at the start and There was a close contest for third place on the band between the on the Sunday morning, combined with a 10-h opening to the whole Cornish group, GE4CRCiP, in the Open section with a tri -band of North America throughout the night gave the single-band beans, and Swansea, GW5Z1..P, the Restricted section winners, entrants a Field Day to remember, and must have provided the with a centre-fed long-wire. Both stations had similar claimed operators of the multi-band stations with the unusual dilemma of scores, but in checking Cornwall gained the edge by virtue of a when exactly to QSY If! A short but unusual opening to VK,ZL more accurate log. around 0330-0430 was also noted, and a few JAs appeared in some logs. 28MHz The band leader and winner of the Frank Hoosen (G3YF) Memorial USA, Canada, Bermuda and Brazil were worked on this band for Trophy is the single-band entry of the Telford & DARS, GE3ZME,P, the first time in many years during NFD. This sentence will possibly with an all-time record 14MHz score of 1,953 points from 640 con- surprise those clubs who in their comments dismissed the band as tacts. The equipment used was a Yaesu FT101E with a TA32 being disappointing. antenna at only 30tt. The operators were G8AX. G3UKV and These results were achieved by groups operating in both sec- G4A UY. tions, Croydon and Bracknell in the Restricted section, and Swansea

RADIO COM MUNICATION September 1977 707 RESTRICTED SECTION N urn ber of Posts Group Callsign 1.8MHz 3-5MHz 7MHz 14MHz 21MHz 28M Hz Total contacts 1 Swansea ARS G W52LiP 270 113 290 857 358 682 2,570 688 2 Surrey RCC (Croydon RSGB Gp) GE6LX/P 268 279 496 648 178 414 2,283 586 3 Northern Contest Gp GE3VM W/P 236 362 474 494 268 158 1.992 588 4 Stockport RS G6UCi/P 278 398 388 637 179 60 1,940 565 5 Oxford & O ARS GE2DU/P 278 223 442 607 296 58 1,904 553 6 Sunderland RSGB Go G3RDIIP 262 359 499 475 163 102 1,860 552 7 Reigate ATS G5LK/P 320 348 456 314 117 230 1,785 488 8 Worcester 6 0 ARC G3GJL/P 346 168 314 373 251 258 1,710 467 9 G4KF Contest Gp 258 234 511 419 41 100 1,563 412 10 Cannock Chase ARS 4 Blake School RC GE3UBG/P 306 294 399 361 134 48 1,542 415 11 Crawley ARC G3TIR/P 360 111 365 464 110 120 1,530 421 12 Sutton Si Cheam RS GE2D MR.P 332 290 232 382 253 34 1,523 454 13 Harlow 6.0 ARS GE6UT/P 250 601 476 124 68 0 1,519 544 14 Hinkley Point (Bridgwater) GE4EBU/P 298 255 192 416 288 60 1,507 436 15 Havering & D ARC G3TTB, P 304 265 404 328 97 5 1,403 432 16 Verolam ARC (St Albans) G3JKSIP 270 425 220 389 12 84 1,400 415 17 Torbay ARS— B' G3GO W/lo 100 208 176 533 303 40 1.360 408 113 Garondon School RC G3MKXIP 0 326 481 195 305 42 1,349 388 19 Gloucester ARS G3MA/P 430 266 375 36 230 o 1,337 376 20 Liverpool D ARS 03AHO/P 326 167 358 453 o 0 1,304 370 21 Guildford 6 D RS—"B" 5500/P 0 401 581 142 54 116 1.294 404 22 Vange ARS GE3101iP 74 256 362 377 152 54 1.275 404 23 Government Communications ARC G3SSOiP 208 255 299 352 159 o 1,273 364 24 White Rose RS GE3XEPIP 378 216 201 302 169 0 1,266 362 25 Stourbridge & 0 ARS GE601/P o 283 104 605 32 234 1,258 382 fBlackpool & Fyide ARS GERGG/P 0 86 352 497 189 12 1,244 359 26 1Stroud ARS G3EKDIP 354 291 308 263 o 3 1.244 337 23 Glenrolhes 6 D ARC—"B" GM4BRM/P 246 201 237 389 70 1 1.221 349 29 Radio Club of Worksop G4CRE/P 174 211 384 244 56 4 1,117 333 30 South East Kent (YMCA) ARC GE3YMDiP 224 434 384 es 1,1to 357 31 Brockland Group GE3GIHTP 6 349 545 165 0 1,065 343 32 Newbury d D ARS G3WCIIIP 195 388 220 106 64 1 1.044 315 33 Thames Volley ARTS G3TVS/P 314 216 348 96 51 1,025 283 34 Chinglord RSGB Go GE83M/P 0 190 377 371 80 1.018 356 35 Perth 40 AR Group GM4EAF/P o 249 635 97 a 1,017 307 36 Caterham Radio Gp G4APL/P o 121 199 544 87 5 1,009 336 37 Gt. Yarmouth 6 0 RC G3YRCIP 214 160 350 265 8 997 316 38 Eccles & D RS GE3GXI P 0 84 226 422 86 818 274 39 First Contest Group GE4FCG/P 56 196 116 417 o 785 235 40 Alnsdale RC GE4E1D/P 76 177 53 160 122 6 654 180 41 Preston ARS G3KUEIP 244 109 42 208 26 629 190 42 Echellord ARS GE3UESflo 0 o D 0 303 303 102 43 Farnborough 6 D RS—"B" G4FRS/P 256 4 a 0 o 263 89 14 DEC (UK) Electronics & ARS GIESSI;to 0 32 12 o o 44 13

and Channel in the Open were but a few who managed to contact A selection of com ments from competitors stations across the Atlantic. "Restricted section excellent substitute for old NFD"— White Rose. Also, there was good European traffic on the Sunday, together "Very fair rules"—Liverpool. with UA9 and 5Z4. Some idea of activity can be seen in that Swan- "No changes, please, in the rules"—Hinkley Point. sea, GW5ZL;P. made 116 contacts and Channel, GE4DAA/P, 103, "Rules ok"—Croydon, and others. which with the multiplier resulted in the best NFD results for years. "Busiest NEO since 1949"—Scarborough, and many oth&s. Next year could see a lot more activity on the band. "DX contest tactics necessary"—Channel. "A fine contest with fantastic conditions"—Southdown. Check logs "Still think the old contest was better"—Garendon School. A considerable number of logs were received Irons fixed and "A muddy good time was had by all" —Sutton. portable stations in the UK and overseas. The HF Contests Com- "Would have been better if we were a sub-aqua club"—Garendon mittee is very grateful for these, as they do help with the checking. School. The overseas station contributing most points to entrants was "Can the HF Contests Committee bring back the sun ?"—Edgware. Leonard Snowdon, 9H1CH, who gave 900 points using all bands "Thanks for the 10 0 drop in temperature—but you overdid itl"— 7-28MHz. Next was ZE1NFDIP who contributed over 300 points, Maidstone. with El5W W ,P and ZS6NFD/P sharing third place with 192 points. "We don't really know how to describe our aerial"—Hinkley Point. No logs had been received from the A6!P or VP9:P groups at the "Part way through the contest our FT401 was pulled off the table as time this report was being prepared. a car moved off the site complete with the power cable"—Crawley. Check logs were also received from G3KRC, G3NYY.'P, G3RPBIP, "We only allowed for 400 contacts in our logs and ran out at 0530"— GE3USE, G6NK, G3VQ0, EP2V W, OK1C1J, OK1M AA, OK1DK W, Maidstone. OK2BBJ, OK2PA W, OK2YAX, OK3BT, OK3CAU, OK3IF. OK3YCA ; "You were a bit mean with your log sheets"—Croydon, Guildford, all of which proved of great value in checking and the operators Cannock, Sunderland, and others. concerned are thanked by the com mittee. "You obviously didn't expect us to do well as you only sent a few log sheets"—G4KF Contest Group. Inspections Representatives of the FIF Contests Committee visited 39 groups in the Open, and 25 groups in the Restricted sections. In all but two of these inspections, the com mittee is satisfied that entrants were How the leaders used the bands operating within the rules and spirit of the contest. There were two Number of QS 0s entries where the equipment in use at the time of the inspection 1-8MHz 3-5MHz 7MHz 14MHz 21M Hz 28MHz did not tally with that shown on the cover sheets for the entries. GE4DAAd' 36 20 133 582 96 103 For future NFDs, the committee is considering the possibility of GM3YOR/P 56 44 169 309 178 50 deducting up to 50 per cent of the checked scores from any group G3RAC/P 64 71 139 229 82 75 for discrepancies of this kind. G W5ZL/P 52 40 84 279 115 118 The committee thanks all those who acted for them in making the GE6LX/P 51 88 141 192 51 63 inspections. GE3VMW P 46 139 137 157 81 28

708 RADIO COMMUNICATION September 1977 "Use of GE prefix caused problems"—Farnborough. "Too many stations tried to work us a second and third time"— Cannock. contest news "Could not start erecting station until after last race and then a mast nearly got trampled on by horses"—Thames Valley (from Kempton Park Race Course).

Com ments from the HF Contests Committee A total of 93 logs were received within the due period. This compares with 103 for the 1976 contest but, in addition to those who submitted entries, there were another 14 groups who started NFD Coventry and Rugby DF Qualifying Event results but had to give up part way through because of equipment troubles, Twenty teams assembled in Bucknell Woods for this contest. Good bad weather or lack of operators. Several groups were flooded and signals were heard from Station "A" but some competitors had were forced to take shelter In nearby buildings, another group dis- difficulty in hearing station "B" due to QRM. At 1330 competitors qualified themselves for breaches of the rules. All these sent In were allowed to leave; some went northwards, some went south- check logs which were most useful for checking purposes. II these wards and others remained in Bucknell Woods under the mistaken 15 non-entrants are added to the 93 contestants, the total taking impression that one transmitter was hidden close to the start. part in NFD compares very favourably with last year. Station "A" was in a southerly direction, five miles from the The committee regrets that the standard of log keeping was not as start, and hidden In thick undergrowth in Wicken Woods. Station accurate as in the past and most entrants have lost points or have "B" was in a northerly direction, 11 miles from the start, near had their logs rescored. The main errors noted by the checking Charwelton, and was hidden in a disused underground water tank sub-committee relate to wrong callsigns, wrong reports and serial near the tunnel entrance on the old Central Railway Line, numbers, and bad arithmetic. In spite of the misgivings of some Peter Woollett was the first competitor to locate a transmitter, entrants, the GE callsign did not appear to cause problems with log signing in at Station "A" at 1417, closely followed by Bill North. keeping. Station "B", despite its hiding place, was found by half a dozen A number of groups seem to have trouble in deciding how many competitors before 1445, and just after 1515 Bill North arrived to points to claim for a particular class of contact. The rules are quite locate his second transmitter. clear, so the difficulty must be lack of geographic knowledge. NO— Time of arrival AS, A9, EP and ZS are not in the Commonwealth—not even for Peon Name Club Station "A" Station "B" NFD I The USSR call areas 1 to 6 are in Europe and count two 1 W. North Mid-Thames 1417; 15151 points, not three as was claimed by over 25 per cent of the entrants. 2 G. Whenham Coventry 15281 1438 Most European countries use /P to signify a portable station, and a 3 A. Simmons Mid-Thames 1530 1443 suffixed number, such as YU3XXX/1, indicates that the station is 4 T. Ouse Mid-Thames 1531 14361 operating from a /A location, In this case In the YU1 call area. Such 5 P. Tyler Mid-Thames 15311 1442 contacts are with fixed stations and count as two points not four 6 J. R. Vickers Stratford 1532 1444 7 C. Plummer Medway 1535 14371 as was claimed by many entrants. 8 P. Lisle Mid-Thames 1537 1437 The problem of duplicate contacts seems to have bugged most 9 M. Hawkins Chelmsford 1430 1553 groups and there are numerous comments and complaints about 10 I. Butson Chelmsford 14118 1554 the difficulty of persuading calling stations that a DSO had already 11 E. Mollart Mid-Thames 14291 1555 taken place. Without exception every log contained duplicates, and 12 D. Holland South Manchester 1433 1556 while many of these were correctly marked there were still a sub- 13 P. Woollett Dartford Heath 1417 1557 14 B. R. POOlo Mid-Thames 1515 1559 stantial number that had slipped through. Unmarked duplicates 15 J. Drakeley Slade 1602 1516 have been penalized at four times the claimed score for the contact. 16 C. Wells Mid-Thames 1540 1603 As mentioned in the report for the Restricted section, there are a 17 P. J. Yentas Salisbury 14181 — number of entries where the details of the aerial used as shown on 18 A. Butcher Chelmsford 1429 — the cover sheet are vague, or even ambiguous. The committee 16 B. Bristow Mid-Thames 14301 — appreciates that some groups may wish to protect their own 20 J. McBurney South Manchester 1534 — A. Simmons and G. Whenham qualify for the Final. interests by not disclosing feed methods, multi-banding techniques etc, but it is necessary that the committee has these details so that they can confirm that the entry is within the rules for the Restricted section. If required the committee will respect the wishes of any Salisbury DF Qualifying Event results group who asks that exact aerial details are not published in the Eighteen teams assembled at the start just off the A345 near the NFD report. SW end of Boscombe Down's main runway. Station "A", operated by G2FIX, was hidden in thick gorse and In conclusion undergrowth in the densest part of Stockton Woods 13 miles W The checking this year was carried out by five members of the HF of the start. Some 300ft of wire thrown over parts which seemed Contests Committee under the overall co-ordination of BRS20249, quite impregnable made things a little tricky. who also provided the various tabulations. The report was compiled Station "B", operated by G4AJD and also hidden in undergrowth, by G6LX, with band summaries by G3IAS, G3MXJ, G4FAM, G6LX was at Millersford Plantation 13 miles S of the start. With 130tt of and BRS20249. The preliminary paper-work, log sheets, cover sheets aerial and 130ft of counterpoise running under the main grid system, and organizing the site inspections was done by G3KKQ. a strong signal was provided at all times, but with rather odd bear- The adjudicators scrutinized 38,449 contacts and were able to ings. cross-check a substantial proportion of these. Checking and report The contest was organized by G2FIX, supported by members of writing took a total of over 250 man-hours; but this is not the end of the Salisbury ReiiES and ably supervised by Sir Evan Nepean, the task, as now the committee has to analyse the many comments G5YN. from entrants, particularly those that relate to the rules and the Timo of arrival conduct of the contest. As was mentioned In last year's report. Pose Name Club Station «A" Station "B" discussions are in progress with other IA RU Region 1 national 1 G. Whenham Coventry 14501 1558 societies with a view to finding common ground for the harmoniza- 2 B. J. Mahoney Rugby 1502 1601 tion of NFD rules. A considerable amount of work has already been 3 P. T. Tyler Mid-Thames 1500 1811 done and it is expected that the matter will be discussed at the 1978 4 D. E. Newman Slade 1617 1438 IARU Region 1 Conference. 5 W. J. North Mid-Thames 1450 1623 B. Bristow Mid-Thames 1623 1459 And so to NFD 1978. As the first weekend in June Is the preferred 7 I. R. Butson Chelmsford 1625 1451 date, and there is no clash with either the Continental Whitsun or 8 C. D. Plummer Medway 1501 1625 our own Spring Bank Holiday, it will be held over the weekend 3-4 9 A. W. Butcher Chelmsford 15001 1625 June. Let us hope that conditions will be as good, if not better, 10 T. C. Gage Mid-Thames 15011 1630 than for 1977, so that it will be a bumper weekend with even higher 11 P. Yentes Salisbury — 1457 record scores. We hope to see you all in NFD 1978. 12 B. R. Poole Mid-Themes 15021 — 13 J. R. Vickers Stratford On Avon 1545 — A last word—to those responsible for posting those precious 14 C. Wells Mid-Thames 15451 — logs to the adjudicators—please make sure the postage stamps are 15 P. Woollett Dartford Heath — 1559 of the correct value. The under-paid postage dues were quite high. Three competitors did not find either station. Next year the logs will be returned to the sender, B. J. Mahoney and D. E. Newman qualify for the Final.

RADIO COMMUNICATION September 1977 709 Summer 1 8MHz Contest results The following general rules, published in the January 1977 issue of Radio Com munication, will apply: 1, 2, 3, 4a, 5a, 6a, 7b, 8, 9a, 10a, A total of 51 logs was received for this contest and in general the 11-22, contest was well received, although several operators com mented This contest is timed to coincide with an IARU Region 1 event. on the lack of activity during the last hour and suggested that the Contestants wishing to enter the IARU contest should complete a contest could well have finished at 2359gmt, although one operator Multiband Summary Sheet and the following multipliers should be did suggest that the finish be extended to 0500gmt. Several com- used on that sheet only: 432MHz, 1; 1,296MHz, 5; 2.304MHz. ments were received on the lack of activity from GW and Mersey- 10. side, and a check of logs received shows there was little or no The VHF Contests Committee Trophy will be awarded to the activity from the following English counties: CBE, DHM, IOW, leading station on 1,296MHz. LCN, MSY, SLP, WKS and YSS. GM3ZSP operated from East Lomond Hill in Fife with an inverted-V with the apex at 150ft, while G3SJJ operated from 011erton with an inverted-V, apex at 150ft, and 3 2.% dipole at 220ft. 432MHz Cumulative Contest rules Most of the checked logs contained some inaccuracies and in 2000-2230gmt, 8, 16, 24 October-1, 9, 17, 25 November fact only one of the top 10 logs contained no errors, after re-scoring All entries and checklogs to: VHF Contests Committee, c,o and checking only very minor alterations had to be made to the R. J. Taylor, G4BEL, 12 The Rampart, Haddenharn, Cambs CB6 3ST. positions of the leaders. The following general rules, published in the January 1977 issue G3KDB of Radio Communication will apply: 1. 2, 3, 4b, 5a, 6a, la, 8. 9a, 10b. 11-22.

SINGLE.OPER ATOR 31 G4ELZ 306 Posn CaHelen Score 32 GM1GK 293 1977 BARTG Contest results 1 GM3ZSP'A 555 33 G2FNK 260 2 G3XUD'A 544 34 G3JEI 252 If a sum mary of the contest were to be made in the minimum of 3 G3XVF ,A 541 35 G4C28 251 words, these would be: "The best yet!''. This was the result of a 4 GIEOK 534 36 031L0 75 number of factors, the main one being a period of improved condi- S G3YMC 531 37 G3ULY 68 tions prior to and during the contest, and these conditions produced 6 G3R WL 530 contacts by both long and short path routes at the same time of day. 7 G3NYY 500 MULTI-OPERATOR As a result of the increased interest in the rtty mode, the number 8 GI3JEX 499 Porn Callsign Score of entries was 40 per cent up on last year, and the number of con- 9 G4FA M 497 G3SJJ A 598 10 GOEIXT 494 2 G3VUM 403 tacts by the leading stations increased by about 50 per cent. In the 11 GaCB0 493 single-operator section there were 107 entries of which 13 were UK 12 G3NKS 484 OVERSEAS ENTRY stations headed by G3YYD in fifth place. Of the 15 stations in the 13 G3SJE 482 Peon Callsign Score multiple-operator section, three were G stations, headed by G3ZRS 14 G3WUX A 477 1 HB9AFI P 243 in sixth position. In the swl section, T. Musson, BRS27262, was in 15 G3YLG 462 2 PAOORP 240 16 G3KOR 454 sixth place. 3 DK6PB 226 17 G3ZJK 444 4 DJ60Z 145 18 G3TLF 441 5 1(", 0J5G W 114 19 G3GC 127 F8EX 114 9th BARTG VHF RTTY Contest rules 20 G3ZSU 426 DLIYA 60 W hen. 1800-23055ml 10 September 1977 and 0700•1200gml 18 September 1977. 21 G4ALG 425 Who. Licensed amateur radio stations within Zones 14 and 15 who are permitted to 22 G3OVL 420 use Illy as a mode of communication. Portable operation Is allowed but must be from 23 G3DCZ 417 DISQUALIFICATIONS ene location for the whole duration of Ihe contest. Contest logs from SWLs will also 24 G3HGE 410 G3WOK,'A See rule 58 ii be very welcome. 25 G4ER W 408 G1CVVH Bands. 144 end 432MHz. Cross-band contacts will not be valid. 26 G3OZM 386 G4CSC All late entries Stations may not be contacted more than once on any one band during the entire 27 G5MY 373 631G W Period of the contest, but an additional contact may be attempted with the same station 28 GICMY 351 if the other band is used. Contacts by means of satellite or repeater will not count 29 GICIUS 343 CHECK LOGS RECEIVED FRO M for points. 30 G3ZDV 1A 314 G5ZT G W8PG Messages will consist of: Time of start of contact. Time in one and to consist of a lull four-flgure group. The use of the expression "Same" or "Same as yours" .111 not be permilted. RST report. No me' three-figure system. June Microwave Contest results Message number. Thin will consist of a three-figure number starting at 001 for the first contact made, and numbers will continue In a consecutive manner Irrespective Entries for this once-popular contest have reached an all-time low, ol the band used. Numbers will cortInue in sequence throughout the total period of with only four stations bothering to compete for placings. Activity the contest. 0TH locator (normal five•symbol locator) or 0TH given either as a town generally was also down despite conditions being reported as above orase bearing and distance in kilometres from a town, and the town must be capable average and the 10 GHz Cumulative running concurrently. The VHF of Identification on a normal tourist map. Contests Com mittee will have to look closely at this contest to see Points. All two-way illy contacts will score In accordance with the distance chart whether it should continue in its present form, be modified to shown below. 0-50km scores 1 point 250-300km scores 11 points attract more entries or be phased out entirely. 50-100krn scores 3 points 300-350km scores 13 points Congratulations to the band winners who will receive certificates. 100-150krn scores 5 points 350-400km scores 15 points G3VPK 150-209km scores 7 points 100-150km scores 17 points 200-250km scores 9 points and pro rata. Scoring. II both bands are used the two scores will be added - each band scoring at the same rate, le there is no multiplier for the 432MHz band. Peon Calisig n Score 050e QTH Best Me K m Note. Proof of contact may be requested in cases where the station worked does not 3,456MH. appear on any other contest logs received. 1 G8AGN P 162 2 ZN52 61 GehlAJ P 66 The final results will be tabulated into two categories, (I) Western Europe and 2 G W8ADP P 77 1 YL25 G3BNL.P 77 (21 UK stations only.

5.760M He G W8ADP. P 77 1 YL25 G313NL,P 77 Additional notes (a) In order to achieve maximum computability and to implement the IARU recom- IOGHz mendations, a speed of 45.5 bauds should be used. 1 G3KSU,P 650 10 2434 G3VPF:P 89 (b) To avoid confusion and congestion around the recognized iffy calling frequencies, 2 G W413RS P 624 a YL25 G8ARC:e P 116 end to make more effective use of the bands, the use of vlo operation by participating 3 G8AGNI. 90 2 ZN52 61 G8MAJ,P 86 stations is encouraged It possible. 4 G W8AEXP.P 43 1 YL25 G3WO G 13 Logs. Use one log per band. Logs to contain the following: dale, time ol start ol contact, RST report sent, message number, time received, callsign of station worked, his RST and message number (which may be combined: for example, 599001), 0TH locator or 0TH received, estimated distance and points claimed. It will be helpful to UHF 432MHz-2.3GHz Contest rules include your own 0T1-1 locator or 0TH at the top of each log sheet. Awards: Certificates will be awarded to the top scorers and runners-up in each 1600-1600gmt, 1-2 October 1977 country. The Judge's decision will be final and no correspondence can be entered All entries and checklogs to: VHF Contests Committee, c:o Mr L. into In respect 01, nconoot entrieS or logs received after the ctosIng date for entries. Hawkyard, G5HD, 100 Shirley High Street. Southampton, Hants All logs must be received by 15 October 1977 to qualify, and should be sent to: SOI 4FB. D. F. Beattie, G3OZF, "Mayorin", Churchway, Stone, Aylesbury, Bucks, England.

710 RADIO COMMUNICATION September 1977 RSGB Region 1 Regional Meeting

3pm Sunday 16 October 1977

Grappenhall Co m munity Centre, Bellhouse Lane, Grappenhall, Warrington, Cheshire RSGB affiliated societies and clubs, and RSGB groups, are invited to submit items for inclusion in "Club News" to their The meeting is open to all RSGB members resident in Region 1. regional representatives (not direct to the editor). Items of news and dates of forthcoming events should Admission Is free. Light refreshments will be available. reach RRs by 25 September for the November issue. The venue is off the A50 close to the junction of the M6/M56 to the south-east of Warrington. Ample parking facilities. REGION 1-RR W. M. Furness, G3SM M, 113 Coniston Avenue, Talk-In on 2m. Further details from G3SMM, OTHR Sale, Cheshire M33 3GT. Ainsdale (AARC)-8, 22 Sept; 6, 20 Oct; 3 Nov. Ainsdale Scout Headquarters. For details contact G2CUZ. Blackburn (East Lanes ARC)-FIrst Thursday In each month, 7.30pm. YMCA. Blackburn. Sec E. A. Lomax. G4DGR. West End University of Manchester (Uo M -loS&TARS)-G3CXX is active PO, Accrington, Lancs. on all hf bands and G8FOT on 2m and perhaps 23cm. Items for Blackpool (B&DARS)-First Monday in the month. Phone G5ND club/magazine/newsletter, or letters from intending members grate- (Blackpool 64508) for details of venue. fully received by sec. cio UMIST. Bolton (B&DARS)-Main meeting first Wednesday in each month North Western Repeater Group-Informal meetings on the third informal meeting third Wednesday in each month, 8pm. Bolton Thursday in each month. 8pm. "Globe Club", Willows Lane, Recreation Club, Kensington Place, Bolton. Hon sec G4FSN (ex Accrington, Lancs. Details from sec G4FZN. G8LXD). Preston (PARS)-Thursdays fortnightly commencing 8 Sept. Bury (BRS)-Main meeting on the second Tuesday of the month. 8pm. "Windsor Castle" (private room), St Pauls Square, Preston. RAE classes and morse instruction every Tuesday as well as Sec G8KTM. informal meetings of club members. 13 Sept ("Railways in Switzer- Salford (Dial House RS)- Wednesdays. 5.30-9.30pm. Dial House, land" by G8FDG), 11 Oct (Constructional competition and film 21 Chapel Street, Salford, Lancs. Net channel 145-25MHz fm-the night), 9 Nov (Giant surplus equipment sale-if you have any club station G3WDH monitors this frequency every club night for surplus giants, bring them along 1). Alternate Tuesdays-Noggin any other station. Details from sec G8JCM, c/o M38 at above and Natter, with G3BRS on the air (cw and phone). 8pm. Mosses address. Youth and Com munity Centre, Cecil Street, Bury. Sec E. R. Thirkell, Stockport (SRS)-Second and fourth Wednesdays in each month, G4FQE, Rochdale 32730. 8pm. Blossoms Hotel, Buxton Road, Stockport. Sec G3FYE. 14 Sept Carlisle (C&DARS)-Mondays, 7.30pm. Currock House, Lediard (Mini-lecture "Dials and scales" by G3NUQ). 28 Sept ("Computers" Avenue, Currock, Carlisle. A very full programme of lectures and by Peter Whalley), 12 Oct (Multimeter project by G8CZ W). New demonstrations has been arranged for the coming months. Full members and visitors always welcome. details from G8DVD. Thornton Cleveleys (TCARS)-First and third Wednesdays in Chester (C&DARS)-Tuesdays, 8pm, except for first Tuesday in each month, 8pm, morse practice from 7.30pm. St John Ambulance the month. YMCA Chester. Further details from the ASR. G3PYU. Hall, Fleetwood Road North (next to "Gardner's Arms"), Thornton. Douglas (loM ARS)-Mondays fortnightly, Keppel Hotel, Creg-ny- Details from sec A. Bullock, G8MKO, 26 Lancaster Avenue, Bea. near Onchan. Sec GD4F WQ (ex GD8LFA), Douglas 22295. Thornton Cleveleys, Blackpool. loM amateurs ask that UK and other amateurs who request direct UK FM Group (Western)-19 Sept (AGM 8pm for 8.30 at Wirral QSLs from GO should send IRCs, as UK postage stamps are not Mercury Motor Inn, Backford Cross, Chester.) 6 Oct (Informal accepted by the Manx Post Office. meeting), 3 Nov (Informal meeting). 8.30 p.m. Legh Arms, Knutsford. Eccles (E&DARC)-Tuesdays, 8.30pm. White Swan. Worsley For details of group apply G3LEQ, tel Kniitsford 4040. Road, Swinton. Sec G4AEQ. Warrington (W&DARS)-Tuesdays. 7.45pm. Grappenhall Com- Lancaster University (UoLARS)- Wednesdays, 8pm. Furness munity Centre, Bellhouse Lane, Grappenhall, Warrington. Sec College. Visitors are welcome, as are sheds on ht and 2m-club R. E. J. Staples, G3MMD, 3 Willow Close. Lymm, Cheshire, tel callsigns are G8DOU and G3ZBY. There are RAE and morse test Lymm 3533. classes. Enquiries to John Morris. G4ANB, Dept of Physics. Wigan (W&DARS)-First and third Wednesdays in each month. Leyland (LHARG)-Second Monday in each month, 7.30pm. Poolstock Cricket Club, Keats Avenue, Poolstock. Sec A. Cunliffe, "Rose & Crown", Ulnes Walton, Leyland. Details from G3XII. G4E11, 50 Langholm Road, Garswood, Wigan. Liverpool (L& DARS)-Tuesdays. 8pm. Conservative Association Winsford (Mid-Cheshire ARC)- Wednesdays. Technical Activi- Rooms, Church Road, Wavertree. Sec G4EST. ties Centre, rear of Verdin Building, Verdin Comprehensive School, Liverpool (North Liverpool RC)-Tuesdays, 8.30pm. Informal Grange Lane, Winsford. RAE class 7pm to 8pm. Morse class every meetings. "Nags Head", Thornton. Crosby, Liverpool 23. Visitors third Wednesday. Net nights 160m Mondays, 8pm, 2m (fm) Tuesdays welcome. Sec R. Porter. 11 Cranmore Avenue, Crosby, Liverpool 8pm. Sec G8HAV. L23 OQD. Wirral (WARS)-First and third Wednesdays in each month. Liverpool University (UoLARS)-Meeting at lunchtime and on 7.45pm. Sports and Recreation Centre, Grange Road West, Mondays, 5pm. Club shack, Reilly Building. The club is active on all Claughton, Birkenhead. Sec G3DLF. bands 80/2m -callsigns G3OUL G8JUL. Details from hon sec, c/o Liverpool Luncheon Club-members wishing to attend should Students' Union or co GW4FJK. contact G3VQT or G2AMV. Manchester (M&DARS)- Wednesdays 7.30pm. 203 Droylesden 1977 North-west A mateur Radio Convention-1718 Sept, Road, Newton Heath, Manchester 10. Sec G8IYX. Lancaster University. Full details from J. R. Morris, Dept of Physics, Manchester (South Manchester RC)-2 Sept (Mini df). 9 Sept Lancaster University. ("DX on top band" by R. P. Smith. G3SV W), 16 Sept (Home-brew test gear-various members), 18 Sept (DF national final run by SMRC), 23 Sept ("DF techniques and review of df national final" by D. C. Holland, G3WFT), 7 Oct ("RTTY", speaker to be announced), 14 Oct ("More reminiscences" by D. Barber, G2AKR), 21 Oct UK FM Group (Western) ("Radio noises" by P. Jones, G2JT), 28 Oct (Discussion evening- Annual General Meeting the future of amateur radio and other topics), 9 Nov (Annual dinner). 8pm. Sale Moor Community Centre, Nooris Road, Sale. Informal 7.30pm for 8pm, 19 September 1977 meetings Monday evenings at "Greeba", Shady Lane, Baguley. Wirral Mercury Motor Inn, Backford Cross, near Chester Full particulars from sec 63V1 W. tel 061-973 3355. Members are asked to try and attend Manchester University (MUARS -G3VUM). Interested parties should contact G4A0S, QTHR.

RADIO COM MUNICATION September 1977 711 The chairman of the Society's M & R Com mittee wishes to Bromsgrove (B&DARC)-9 Sept (Surplus sale), 14 Oct (Film thank all ARs, ASRs and club and society representatives in show), 15/16 Oct (JOTA). 8pm. Avoncroft Art Centre, Bromsgrove. Region 1 who attended the evening gathering following the com- G9JTK. mittee meeting in Manchester on 14 July. Burton-on-Trent (B upon T&DARS)-7 Sept (Df exercise from T-junction at Yoxa11-7.30pm), 21 Sept (Df exercise from five lane Region 1 area representatives. Add: Central Cheshire-G3LEQ ends, Needwood-7.30pm). G3ACR. and Cumbria (North)-G3VIJ to the list in the May issue. Cannock Chase (CCARS)-First Thursday in each month (Busi- ness meeting), other Thursdays (HF and vhf club stations, natter- nites, morse classes, talks etc). Visitors welcome. 9pm. Bridgtown Social Club, Walsall Road, Greenock. G4CHI. Coventry (CARS)-Fridays, 8pm. Baden Powell House, 121 St REGION 2-RR R. C. Andreang, G4CM T, 6 Beech Avenue, Nicholas Street, Radford, Coventry. G8DMI. Bilton, Hull, Humberside. Coventry Technical College (CTCARS)-Mondays and Thurs- Barnsley (B&DARS)-Fourth Friday in each month. 7.30pm. days. 7pm. Winf ray Annexe of the College. G8ISJ. King George Hotel, Peel Street, Barnsley. Sec G3LRP. Coventry (University of Warwick ARS)- Wednesdays during Denby Dale (DD& DARS)- Wednesdays, 7.30pm. Pie Hall, term. Talk-In on S20. 7pm. Cryfield Farm, University of Warwick, Denby Dale. Visitors always welcome. Sec G3FQH. Coventry. Vice-president G8MIA. Goole (G&DARS)-Fridays, 7.30pm (during school term only). Hereford (HARS)-First and third Fridays in each month. Civil Goole Grammar School. Details from chairman G3VBI. Defence HQ, Gaol Street, Hereford. G4CNY. Halifax (Northern Heights ARS)-7.45pm. Peat Pitts Inn, Ogden, Lichfield (LARS)-First Monday and third Tuesday in each month, Halifax (four miles north of Halifax town hall). Sec G3MD W. 8pm. Swan Hotel. Tuesday meetings are natter-nites. Sunday net Hornsea (HARS)- Wednesdays, 8pm. Rear of Victoria Hotel, noon, 21-150MHz. G3RTY. Hornsea (facing Hornsea Mere). Grateful thanks to all help for our Lichfield (Chad RC)-Alternate Wednesdays, com mencing 14 rally and attendance RR2 Rep. Sec G4CHH. Sept, 8pm. The Naval Club, Burton Old Road, Lichfield. G4ESK. Hull (H&DAR S)-Fridays, 7.30pm. Dorchester Hotel, Beverley Mid-Warwickshire (MWARS)-5 Sept (Surplus sale), 19 Sept Road, Hull. Sec G3LZQ. ("Home-made printed circuit boards" by G8J WC), 3, 17 Oct, 7 Nov. Hull (HUR&ES)-Friday 1pm, Room 313B, Union Building. All 8pm, 61 Emscote Road, Warwick. G8CXL. amateurs invited. G8HUC is active on 2m ssb. Enquiries to G4FVP, Redditch (RRC)-Second and fourth Thursdays in each month, 210 Whitehall Road, Tyne and Wear, during vacation or to Clive 8pm. WRVS Centre. Salop Road, Redditch. G3EVT. Davies, Union Block, during term. Leeds (White Rose RR)- Wednesdays, 7.30pm. (Lectures start Shrewsbury (Salop ARS)-Thursdays, 7.30pm. New members welcome. The Albert Hotel. Smithfield Road, Shrewsbury. Joint 8pm). Sec G4DZI. secs Bob Carter, 11 Ash Close, Sutton Farm, Shrewsbury SY2 61-IU, Leeds (LUUARS)-Tuesdays, 8pm. Union Annexe (second floor), and Dave Doody, 56 Ellesmere Road, Shrewsbury SY1 2QP. Woodhouse Lane. All new students welcome. Sec G4CNG, QTHR, Solihull (SARS)-20 Sept (Surplus sale), 18 Oct (AGM). 7.30pm. or at "E" block, Lupton Flats, Alma Road, Leeds 6. during term. The Manor House, High Street, Solihull. G4EQF. Otley (OR&ES)-Tuesdays, 8pm. 14 Back of Court House Street, Stoke-on-Trent (S-on-TARS)-Thursdays, 7.30pm. 2A Race- Otley. Sec G8DFZ. Scarborough (SARS)-Fridays, 7.30pm. Scarborough Technical course Road, Oakh III, Stoke-on-Trent. G4C WN. Stoke-on-Trent (North Staffs ARS)-First and third Mondays in College, Corby Road, Scarborough. Sec G3RTN. PRO Charles each month-lectures etc. Second. fourth and fifth Mondays in each Whitaker, 1 Ryefield Close, Easel eld, Scarborough. month-natter nites. Raynet and club station G4BEM. Newcomers Sheffield (SU&PRS)-University- Wednesdays in term, 1pm. welcome. 7.30pm. Harold Clowes Community Centre, off Dawlish The "Red Deer", off Main Street, Details G4BXN. Polytechnic-This club must expand this year if the Students' Drive, Bentilee, Stoke-on-Trent. G3YBY. Stourbridge (StARS)-Informals on the first Tuesday in each Union is to continue financial support. Details G4CYA, QTHR, tel month, 9pm. "Shrubbery Cottage" public house. Heath Lane, Sheffield 303030. Oldswinford, Stourbridge. 19 Sept ("Radio in prisoner of war Sheffield (Association of Sheffield ARCs)-Mondays, 7.45pm camps" by Tom Douglas, G3BA), 17 Oct ("GB3BM repeater" by (note first Monday in month, during term). This group meets to Haydn Bate, G8A MD). 7.45pm. Longlands School, Brook Street, bring together the several smaller clubs in the area and to provide Stourbridge. G4CLX. a joint newsletter. 3 Oct (Junk sale), 7.30pm, room 3107, Sheffield Stratford-upon-Avon (S-on-A& DARC)-Meetings will be Polytechnic. AGM, 8.30pm, room 3106. Details G4CU W, QTHR, tel resumed in Sept. New members welcome. G4EXR. Tel Stratford Sheffield 363927. Sheffield (ARS)-Third Monday In month, 8pm. Sheaf House 5638. Sutton Coldfield (SCRS)-Second and fourth Mondays in each Hotel. New club nets with slow morse on 144.18MHz and 28-75MHz, month. 7.30pm. Central Youth HQ, Clifton Road, Sutton Coldfield. both frequencies, 8pm, 2nd, 4th and 5th Mondays. Sec Mrs Liz Furness, 4 Goodere Drive, Polesworth, Tamworth, W akefield (W&D ARS)-7.30pm, mes Road School, Wakefield. Staffs B78 1BZ. Sec G3W WF. Tam worth (TARS)-Second and fourth Mondays in each month. York (YARS)-Fridays. 7.30pm (except for the third Friday in the Indoor Sports Centre, Corporation Street, Tamworth. New members month). United Services Clubroom, 61 Micklegate, York. Visitors welcome. G4 EU F. always welcome. 10 Sept (Special event station G3H W W on behalf of York Scout Council at Snowball Plantation, Stockton-on-Forest, Telford (T&DARS)- Wednesdays, 7.30pm. Phoenix Centre, near York. (Plus JOTA in October.) 21 Oct (Annual dinner), Abbey Webb Crescent, Dawley. Visitors welcome. G8MXS. Tel Much Wenlock 357. Park Hotel, York. Sec G3WVO. Willenhall (W&DARS)-Alternate Wednesdays. Morse classes Fulford (FARS) -Tuesdays 7.30pm. 31 George Street, York. Rag available at the end of each meeting. "The Three Crowns", Stafford CNE WS, morse, RAE assistance etc. Sec G5KC. Street, Willenhall, G3YHN, XYL. RR2 thanks all secretaries for their help. W olverhampton (WARS)-12 Sept (Natter-nite), 19 Sept (Dis- cussion on the modification of commercial radiotelephone equipment), 3 Oct (AGM), 10 Oct (Natter-nite), 17 Oct (Members' slides and films), 31 Oct (Natter-nite), 7 Nov ("The Yaesu Musen FRG-7 receiver" by Peter Burden, G3UBX, and John Cook, G8EDG). 8pm. REGION 3-RR H. S. Pinchin, G3VPE, 61 Cole Bank Road, Neachells Cottage, Danescourt Road, Stockwell End, Tettenhall, Hall Green, Birmingham B28 8EZ. Wolverhampton WV9 9PH. G8EDG. Birmingham (Birmingham University RS)-Every Tuesday Worcester (W&DARC)-5, 17,26 Sept (AGM), 3 Oct. 8pm. The Old during term, 7pm, Students' Union. G3IUB. Sec G4CKK. Pheasant, New Street, Worcester. G4DX E. Birmingham (Midland ARS)-20 Sept. 18 Oct (AGM). 8pm. Room 110, University of Aston, Gosta Green, Birmingham. G3ZKQ. Birmingham (Slade RS)-Alternate Fridays, com mencing 16 Sept. 8pm. The Com mittee Room, Church House, Erdington, Birmingham. G4FGF. REGION 4-RR T. Darn, G3FGY, Sandham Lane, Ripley, Birmingham (South Birmingham RS)-Shack night Fridays. Derbys. 7.30pm. 7 Sept, 5 Oct ("Video" by 651(S), 2 Nov (AGM). 8pm. Derby (DA DARS)- Wednesdays, 7.30pm. Morse classes Tues- Hampstead House, Fairfax Road, West Heath, Birmingham days and Fridays when arranged, 119 Green Lane, Derby. 7 Sept 631 3QT. G8KPA. (Bring and buy sale), 14 Sept (Surprise night), 21 Sept ("Hi-fi, the

712 RADIO COMMUNICATION September 1977 modern curse for interference", causes and cures by G3VG W), Reading (RARC)-23 Aug (Brewery visit!), 6 Sept (Junk sale). 28 Sept (Film or video show), 5 Oct (Junk sale), 12 Oct (Technical 8pm. White Horse, Emmer Green, Reading. Sec G4CCC. topics). Derby (NH ARG)-Fridays, 7.30pm. Nunsfield House, BouIton Lane, Alvaston, Derby. Grimsby (GARC)-First and third Thursdays in each month. REGION 7-RR N. A. Smith, G3HFO, 7 The Byeways, 8pm. Alexandra Social Club, Cleethorpes. Leicester (LRS)-Mondays. 7.30pm. Club House, Giirose Estate Surbiton, Surrey KT5 8HT. A meeting of affiliated society representatives In Region 7 was held Cottage, off Groby Road, Leicester. The Leicester Club were the on 30 June. The main subjects discussed were misuse of repeaters, winners of the East Midlands Amateur Radio Group Contest which was held in the spring. the RSGB International Radio Com munication Exhibition at Alexandra Palace in May, and methods of recruiting new members Mansfield (MARS)-First Friday in each month, 7.30pm. "The New to affiliated societies using information from HQ on new members Inn", Westgate, Mansfield. of the RSGB. Another meeting will be held in September to co- Melton Mowbray (MM ARS)-7.30pm. St John Ambulance Hall, ordinate views on the future of the RSGB in preparation for the Asfordby Hill, Melton Mowbray. Nottingham (ARCON)-Thursdays, 7.30pm. Sherwood Com- Regional Representatives Conference on 24 September. munity Centre, Mansfield Road, Nottingham. Addiscombe (AARC)-Tuesdays, 9pm. "Spreadeagle", Portland Nottingham (NURC)-Alternate Thursdays during term time. Road, Woodside. Sec G3SJX. Details from Roger Dixon, G4BVY, c/o Students' Union or QTHR. • Ashford, Middlesex (Echelford ARS)-Second Monday and last Loughborough (ARC)-Loughborough Students G8KSZ, Thursday In each month. 7.30 for 8pm. St Martin's Court, Kingston QTHR, would like to hear from anyone interested in joining the Crescent, Ashford, Middlesex. Sec G3TDR, tel Staines 56513. club in the new term. Bexley Heath (North Kent RS)-Second and fourth Thursdays, QRP Club-This very active international club Is now run from the 8pm. St Mary's Institute, 2 North Cray Road, Bexley. Sec G4ARQ. Nottingham area; they put out a very good newsletter with some Coulsdon (CATS)-First Thursday in each month, 7.30 for 8pm. very interesting QRP circuits. 10th Purley Scout Hall, Chipstead Valley Road, Coulsdon. Third Morse at Mablethorpe-A repeat of the morse class of a few years Monday in each month, 7.30 for 8pm. 1st Purley Scout Hall Purley ago will be held, numbers permitting, at the Ten meson Secondary Park Road. Purley. Sec G4DLD, tel Burgh Heath 59956. School, Mablethorpe, on Wednesday evenings com mencing In Cray Valley-First and third Thursdays. 8pm. Eltham United September. Further information from G4CTE, QTHR. Reform Church Hall, 1 Court Road, Eitham, London SE9. Sec G3Y WO. Croydon (Surrey Radio Contact Club)-First and third Wednes- days in each month, 7.30 for 8pm. TS "Terra Nova", 34 The REGION 5-RR P. F. ChlIcott, G4BBA, 258 Coneygree Road, Waldrons, Croydon. Sec G3F WR, tel 01-657 3258. Peterborough, PE2 8LR. Crystal Palace (CP&DRS)-Third Saturday In each month. Bedford (B&DARC)-1 Sept (SSB FD plans), 3/4 Sept (SSB FD), 7.30pm. Emmanuel Church Hall, Barry Road, London SE2'2. Sec 8 Sept (Junk sale), 15 Sept (The "kiss" principle by G8BNE), G4AVV, tel 01-653 4340. 22 Sept ("Get going on rtty" by G4FEV). 8pm. United Services Club, Guildford (G& DRS)-Second and fourth Fridays In each month. Broadway. Sec G4FEV. Model Engineers HO, Stoke Park, Guildford. Sec G4BHQ, tel Cambridge (C& DARC)-Fridays, 7.30pm. Corporation Yard, Guildford 76375. Victoria Road. Sec G4B AO. Kingston (K&DARS)-Second Wednesday in each month. Cambridge (CU WS)-Tuesdays during term. Sec G4DZY, 8.15pm. Berrylands Scouts and Guides HO, Stirling Walk, Raeburn Christ's College. See us at society's fair on 4/5 Oct. Avenue, Surbiton. Sec G4APG. Corby (CTCARG)-Mondays, 7.30pm. Corby Technical College. New Cross (Clifton ARS)-Fridays, 8pm. 225 New Cross Road, Clubhouse and GB3CI in grounds. London SE14. Details from R. A. Hinton, 68 Camilla Road, Ber- Dunstable (DDRC)-Fridays. 8pm. Chews House, 77 High Street mondsey, London 5E16. South. Sec G3WXS. Reigate (RATS)-FIrst Tuesday In each month, 8pm (Natter March (M&DRAS)-Tuesdays, 7.30pm. 2 Grays Lane. Sec G8GNE. nights). Marquis of Granby, Hooley Lane, Redhill. Third Tuesday Northampton (NRC)-Thursdays, 8pm. Spencer Dallington Com- in each month, 8pm. Constitutional Centre, Warwick Road, Redhill. munity Centre, Tintero Avenue, off Gladstone Road. Sec G8LHR. Sec G3XSZ. Peterborough (GPARC)-22 Sept ("Use of components" by Sutton and Cheam (S&CRS)-14 Sept, 7.30pm. Ray's Social John Costin, G8BSO), 27 Oct ("Weather on rtty" by G. E. D. Club, London Road, Cheam (Junk sale). 22 Sept, Sutton College of Allcock). 7.30pm. Southflelds Junior School. Sec G4BBA, tel 65213. Liberal Arts, Cheam Road, Sutton (G8SM on the stereocode Peterborough (PR&SS)-3rd Friday each month, 7.30pm. Scout method of reading morse). 20 Oct, Sutton College of Liberal Arts. Hut, Occupation Road. Sec G3EEL. 26 Oct, Ray's Social Club. Sec G2DMR. Shefford (S&DARS)-Thursdays, 8pm. Church Hall. Sec GBH HO. Thames Ditton (Thames Valley ARTS)-4 Oct (South Midland Communications). 1 Nov, (G3XZV on antennas). 8pm. Giggs Hill Green Library, Giggs Hill Road, Thames Ditton. Sec G3ZN W. Wimbledon (W&DRAS)-Second and last Fridays in each month, 8pm. St John Ambulance HQ, 124 Kingston Road, Wimbledon REGION 6-RR F. S. G. Rose, G2DRT, 84 Cock Lane, High S W19. Sec G3XTC, tel 01-644 3698. Wycombe, Bucks HP13 7EA. Banbury (BARS)-Fridays, 7.30pm. 43 North Bar, Banbury. New members and visitors welcome. Sec S. L. Terry, tel Banbury 4769. Bracknell (BARC)-Mondays, 8pm. Coopers Hill Centre (adjacent to station). 12 Sept (Inter-club quiz), 26 Sept (Natter-nite), 10 Oct REGION 8-RR D. N. T. Williams, G3M DO, "Seletar". New (Cheese and wine), 24 Oct (Wa), 7 Nov (Film nite). Other Mondays, House Lane, Thanington, Canterbury, Kent. cw classes. Sec G3YMC. Brighton (B&DRS)-14 Sept ("Oscilloscopes" by G3XUS). 8 Sept Burnham Beeches (BBRC)-First Monday in each month, 8pm. ("Radio interference"-GPO), 12 Oct ("Computers" by G3XJG), Hedgerly Scout HQ. Sec Peter Flynn, tel Farnham Common 2609. 28 October ("Aeronautical radio" by G30EM). Further details from High Wycombe (Chiltern ARC)-Fourth Wednesday in each N. Hewitt. G8J FT, 74 Carlyle Street, Brighton BN2 2XW. month, 8pm. 42 Castle Street, High Wycombe. Sec G4FRL. Burgess Hill (Mid-Sussex ARS)-7.45pm. Marie Place, Burgess Maidenhead (M&DARC)-16 Aug (Demonstration-"PCB tech- Hill. Details from G3PEQ. niques" by G3ZLQ). Red Cross Hall, The Crescent, Maidenhead. Canterbury (East Kent RS)-Details of future venue and pro- 24 Aug (Informal). 8pm. The Beehive, White Waltham, gramme from G8GHH. Milton Keynes-for next meeting please ring sec G3THC, tel Chichester (C&DARC)-First Tuesday and third Thursday in Milton Keynes 316730. each month. Lancastrian Boys School. Details of future events Newbury (N&D ARS)-First Monday in each month, 7.30pm. from G4ETU, tel 0243 88069. Newbury College of Further Education, Oxford Road, Newbury. Crawley (CARC)-United Reform Church Hall, lfield, Crawley. Sec G4EEE. Details of future events from G3MGL. Oxford (O&D ARS)-Second and fourth Wednesdays in each Dartford (DH DFC)-Second Friday in each month. The Scout month, 7.30pm. Civil Service Sports Club, Marston Road, Oxford. House, Broomfield, Dartford. DF hunts 11 and 23 Sept, details from Visitors welcome. Sec G4BHR. Jeanette Maggs, 25 Leybridge Court, Eltham Road, Lee SE12.

RADIO COMMUNICATION September 1977 713 Dover (South-East Kent YMCA ARC)—Details of future events Pembroke (PRSGBG)—Last Friday in each month, 7.30pm. from G8KEN, 14 Victoria Road, Capel-le-Ferne, Folkestone. Defensible Barracks, Pembroke Dock, Dyfed. Details from sec Eastbourne (Southdown ARS)-24125 Sept (Return visit to Radio G W3XJQ. Club de Normandie, Rouen, France), 3 Oct (Second annual junk Pontypool (PRSGBG)—Tuesdays, 7pm. Education Settlement, sale). Chaseley Home, South Cliff, Eastbourne. Details from sec Park Hill Road, Pontypool. Details from GW3JBH. G8CVV, pro G3LFZ. Port Talbot (British Steel Corporation ARS)—Thursdays, Gravesend (GRSGBG)—Mondays, 7.30pm. The Windmill Tavern, 7.30pm. BSC Sports and Social Club, Margam. Details from Shrubbery Road, Gravesend. G W4ESV. Hastings (HERC) (ITT(H)S&AC)—Details of future events for Rhondda (RARS)—Every other Thursday, 7.20pm. Transport both units from G8DNO. Employees' Club, Porth. Details from GW3PHH. Horsham (HARC)—First Wednesday in each month. Civil Defence Sully (S&DS WC)—Mondays, fortnightly, 7pm. Sully Bowls and HQ, Moons Lane, Brighton Road, Horsham. Details of future events Social Club, 58 South Road, Sully. Details from sec GW8JHF. from G3NPF. Swansea (SARC)—Tuesdays fortnightly, 7.30pm. The Commercial Maidstone (MY MCAARS)—First and third Fridays devoted to the Inn, Killay. Details from sec GW4AYJ. beginner, RAE and morse tuition, 7.30pm. Alternate Fridays, a wide range of lectures and use of the club shack. Melrose Close, Loose, Maidstone. Details from Harry Poppy, G8KMX, tel Maidstone 61792. Medway (MARTS)—Fridays, 7.30pm. Aurora Hotel, Gillingham. REGION 11—RR P. H. Hudson, G W3IEQ, "Silhill", Dinas Details from P. J. Poole, G4EVY, 5 River Drive, Strood, Rochester, Dinile, Caernarvon LL54 5TW. Kent. Rhyl (R&DARC)—It is regretted that this club has been closed Ramsgate (Kent Coast ARC)—Details of meetings from G4DTA. until further notice. Tunbridge Wells (West Kent ARS)—Details of future events Conway Valley (CVARC)—Second Thursday in each month. The from G8LMV. Quaries, Llandulas, Colwyn Bay. Worthing (W&D ARC)—Details of future events from P. J. Bangor (UCN WARS)—Thursdays, 7.30pm. School of Engineer- Robinson, G8MSQ. Tuesdays, 8pm. Adult Education Centre, Union ing Science, Dean Street, Bangor. Prospective members please Place, Worthing. contact the sec. Kent Repeater Group—Details of membership and events from G3XDV, 5 Lambs Walk, Whitstable. Kent. Sussex Repeater Group—Information available from G8HVV. REGION 12—RR Frank Hall, GM8BZX, 45 Priory Cottages, Lunanhead, Forfar, Angus DD8 3NR. Aberdeen (ARS)—Fridays, 8pm. Cowdray Club, 5 Fonthill Road, REGION 9—RR H. W. Leonard, G4UZ, 4 Start Bay Park, Strete, Aberdeen. 9 Sept (Closed), 16 Sept (Talk on the FT221R and TR7200G), 23 Sept (Mini-lecture and extraordinary general meeting), Dartmouth TQ6 ORY. 30 Sept (Latest repeater information), 7 Oct (Junk sale), 14 Oct (Talk Camborne (Cornish RAC)-1 Sept ("An introduction to rtty" by on the IC201 and IC211E), 21 Oct (AGM), 28 Oct (Presidential G4CVY), 6 Oct ("The 70cm repeater" by G3TDJ), 3 Nov (Sale of surplus equipment). 7.30pm. SWEB Clubroom, Pool, Camborne. address), 4 Nov (Junk sale). Sec GM4BKV, Dundee (Kingsway Technical College ARC)— Wednesdays, Cornish net each weekday on 3.715MHz 10am, and on Sundays 6.30prn. Kingsway Technical College. Sec Robert Officer, 17 Broom- 3-692MHz at 11am. Visitors to club meetings most welcome. Full well Gardens, Monikie, Broughty Ferry, Dundee DD5 3QP. details from G3NKE, tel Camborne 712419. Inverness (Technical College ARC)—Meetings commence Exeter (EARS)—Second Monday in each month, 7.30pm, Com- second Wednesday in September, 6.45pm in room C30. Club munity Centre, St Davicis Hill, Exeter. Details from G3H MY. activity presently at an all time low and it is hoped for a much Newquay (N&DARS)—Alternative Wednesdays, 7.45pm. Trevi- more enthusiastic winter session. As a project the club recently glas School, Newquay. Details from G8GOR, tel Newquay 4168. built an rtty converter which will be in use during the winter period. North Devon (NDRC)—Second Wednesday in each month at Sec John Reid, 37 Mac Ewen Drive, Inverness. QTH of G4CG, fourth Wednesday at QTH of G2FKO. Full details Lerwick (ARC)— Wednesday evenings at Annsbrae House, from G4CG. Lerwick. Sec GM3HTH. Plymouth (PRC)—First and third Tuesdays in each month. 7.30pm. Moray Firth (MFARS)— Weclnesdays, 7.30pm. Elgin Technical Virginia House, Bretonside, Plymouth. Visitors most welcome. College. Sec GM8LVG. G4EJO. Saltash (S&DARC)—First and Third Fridays in each month. Perth (P&DARG)—The club are presently investigating the possibility of operating a repeater in the Perth area. Full details of 7.30pm. Burraton Toc-H Hall, Saltash. Sec G8LLR, tel Plymouth meetings etc from sec GM4DQJ. 771135. Torbay (TARS)—Fridays, with special meeting on last Saturday of each month. 24 Sept ("Speech processors"). 7.30pm. Rear of 94 Belgrave Road, Torquay. Torbay net, weekdays 3.756-3.764MHz, Mondays to Fridays 1030, Saturdays 0930. Visitors to club meetings always welcome. Full details from G3UIQ, tel Newton Abbot 3025.

REGION 1O—RR R. G. Barrett, GW8HEZ, 23 Carshalton Road, Beddau, Pontypridd, Glam. Barry (BCoERS)—Thursdays, 8pm. Barry Rugby Football Club, Reservoir Road, Barry. Details from sec GW3VBP. Blackwood (BARS)—Fridays, 7pm. Oakdale Community Centre, Oakdale near Blackwood. Details from sec GW3KYA. Bridgend (Glamorgan VH FUHF Group)—Second Wednesday in each month, 7.30pm. NCB Social Club, Tondu, near Bridgend. Details from sec GW8HEZ. Cardiff (CRSGBG)-11 Sept (Mobile picnic, Porthkerry Park, Barry, from 12 noon), 12 Sept ("The Time Code Clock" by G W4C0J), 10 Oct (AGM and constructors' contest), 17 Oct (Social evening—cabaret, music and dancing at Roath Conservative Club, Cyril Crescent, Cardiff). 12 Sept and 10 Oct, 7.30pm, Pantmawr Inn, Pantmawr Estate, Cardiff. Details from sec GW3VO W, 9 Millrace Close, Lisvane, Cardiff. Merthyr (Hoover ARS)—Mondays 7.30pm. Hoover Social Club, Pentrebach, Merthyr. Details from sec GW8HHY. QTHR. Bob Kerr, GM4FDT, (left) with George Pople, GM4DKL, who Newport (NARC)—Mondays, 7pm. Adult Education Settlement, operated a demonstration station at a recent Hobbies & Brynglas Road, Newport. 12 Sept ("Linear amps" by GW3N WS), Crafts Exhibition in the Com munity Centre, Lairg, Sutherland. 10 Oct ("Oscilloscopes" by GW3N WS). Details from sec GW8MER. Photo: A. M. Smith

714 RADIO COMMUNICATION September 1977 REGION 13-RR A. B. Givens, GM3Y OR, 41 Veronica Crescent Kirkcaldy, Fife KY1 2LH. Berwick upon Tweed (Border A RS)-First and third Fridays In each month, 7.30pm. Roxburgh Hotel, Berwick upon Tweed. Details from GMBH°. Dunfermline (DARS)-Second Wednesday in each month, 7.30pm. CCTV Studio, Pittencreiff School, Maitland Street, Dunfermline. Details GM3MGX, tel Limekilns 313. Edinburgh (E&DARC)-Tuesdays, 7.30pm. City Observatory, Carlton Hill, Edinburgh. Details from GM4B WT, tel 031-668 1119. Edinburgh (Lothians RS)-Second and fourth Thursdays in each month, 7.30pm. Adult Education Centre. Riddles Court, High Street, Edinburgh. Details from GM4BYF, tel 031-447 3201. Glenrothes (G&D ARC)-First Sunday in each month and every Wednesday. 7.30pm. Old Primary School, Provosts Land, Leslie. Fite. Details from GM3YOR, tel Kirkcaldy 200335.

REGION 14-RR (Post vacant) Glasgow (WoSARS)-16 Sept ("RSGB"), 30 Sept ("RTTY" by GM3SZP), 28 Oct ("VHF ta" by GM8BBA). 8pm. 22 Robertson Street, Glasgow. Details from GM4FIDM.

REGION 15-RR H. J. Campbell, 26 Kilcoole Park, Belfast BT14 Bally mena (BRC)-Tuesdays. 8pm. 86 Old Cullybackey Road, Ballymena. RAE and morse classes. Fridays, club night; Sundays, special projects, 3pin. 2 Sept (AGM). Sec GI8LSF. Bangor (B& DARS)-First Friday in each month, 8pm. Redcliff Road, Bangor. 2 Sept (AG M). Sec GI4AA M, 14 Manse Road, Bangor. Belfast (QUoBRC)-Tuesdays, 8pm. Queen's University Radio G3NYK (bottom right) operating G4BPO, the 14MHz demon- Club, 37 Fitzwilliam Street, Belfast, All welcome, stration station on the air during the Families Open Day at Belfast (CoBY MCARC)-Club now active at new address, the PO Research Centre, Martlesham YMC A. Wellington Place, Belfast. Belfast (BRSGBG)-Third Wednesday in each month, 8pm. 90 Belmont Road, Belfast. 21 Sept (AGM). Come along and help arrange winter programme. Further details from GI8FOK. Vange (VARS) -Thursdays, 8pm. Youth Hall, Barstable Tenants' Carrickfergus (CYMC ARC)-Last Monday in each month, 8pm. Com munity Association, Long Riding, Basildon. Details from Mrs Carrickfergus YMCA. New members very welcome. Sec C. D. Thompson, 10 Fearing Row, Basildon SS14 1TE. Morrison, GI8KZU, 3 Donegall Square, Carrickfergus, Co Antrim. Mid-Ulster RSGB Group-First Sunday in each month at QTH of GI4BAC, 4 Sept (AGM). Sec GI3W WY. North Ulster (NURSGBG)-For details contact GI3UHL. QTHR. REGION 17-RR L. Hawkyard, G5HD, 100 Shirley High Street, Southampton, Hants. Basingstoke (BARC)-First Saturday and third Wednesday in each month, 7.30pm. Chineharn House, Popley, Basingstoke. Sec G3CBU. REGION 16-RR R. E. G. Kendall, GBBNE, " Wesley", Basingstoke (UK FM Group, Southern)-Chineharn House, Ranworth Road, Hemblington Corner, Blofield, Norwich Basingstoke. Details from PRO G8ECO. NR13 4PJ. Bournemouth (Wessex ARG)-First and third Fridays in each Chelmsford (CARS)-First Tuesday in each month, 7.30pm. month, 7.30pm. The Dolphin Hotel (club room), Holdenhurst Road, Marconi College, Arbour Lane, Chelmsford. Details from R. Brooks, Bournemouth. Sec G. Cole, G4EMN, tel Bournemouth 20027. 30 Rowan Drive, Heybridge, Maldon. Chippenham (C&DARC)-Tuesdays, 7.30pm. Sheldon School, Colchester (CRA)- Wednesdays, 7.30pm. 114 Ipswich Road, Hardenhuish Lane, Chippenham. Sec G8BXG. Colchester (above Candor Motors). Details from G3YAI. Fareham (F& DARC)- Wednesdays 7.30pm. Porchester Com- Great Yarmouth (GYRS)-Last Thursday in each month, 67 munity Centre, Room 9. Sec D. Thompson, tel Fareham 2799. Southdown Road, Great Yarmouth. Details from G3NHU. Farnborough (F& DRS)-Second and fourth Wednesdays In each Harlo w (H& DRS)-Tuesdays, 8pm. Mark Hall Barn, First Avenue, month, 7.30pm. Railway Enthusiasts' Club, Access Road, off Hawley Harlow. Details from G3WUX. Lane, Farnborough. Sec G4FEA. Ipswich (IRC)-14, 28 Sept (To be arranged), 12 Oct ("Mellor data" Guernsey (GRES) -Tuesdays and Fridays, 8pm. Details from sec by G. Mellor), 9, 30 Nov ("Aerials" by C. Chambers. G8KET). GU8ITE. PO Box 100, Guernsey. Ranelagh Road School, Ipswich. Horndean (H&DARC)-Second Thursday in each month, 7.30pm. Loughton (L& DRS)-Second and fourth Fridays in each month, Merchiston Hall, Horndean, Net Sundays 6.30pm, 21-40MHz, Sec 8pm. Loughton Hall, near Debden station. Details from G8DZH. G4CHO. Lowestoft (L&DARC)-Fridays, 7.30pm. Morse class every Jersey (JARS)-Sundays, 10.30am, and Fridays, 8pm. Le Hocq Tuesday. YMCA, Park Road, Lowestoft, Tower, St Clement, Jersey, Sec Mary McTaggart 19 Parade Road, Martlesham (MRS)-7 Sept (TX(rx test session-G4FZZ), 5 Oct St Helier. (Postal mechanization and automation). Details G3ZNU, PO Res Poole (PRAS)-Last Friday in each month, 7.30pm. Poole Tech- Centre, Martlesham. nical College. Sec Graham Tizzard. tel Poole 4641 est 34. Norwich (Norfolk ARC)-7 Sept (Visit of RSGB President), Portsmouth (P&DRC)- Wednesdays, 7.30pm. Portsmouth Com- 14 Sept (Air traffic control), 21 Sept (CW tuition), 28 Sept (Surplus munity Centre, Malins Road, Buckland, Portsmouth. G3CNO. equipment auction), 5 Oct (CW tuition, committee meeting), 12 Oct Salisbury (SR&ES)-Tuesdays, 7.30pm. Salisbury Activity Centre, (Special general meeting), 19 Oct (CW tuition), 26 Oct ("Crystals Wilton Road. Sec G3FIX. and crystal oscillators" by D. Hill). Southampton University (SUARC)-Tuesday evenings, also Norwich (U of East Anglia R&EC)-Details from P. Gowen, informal meetings every lunchtime in the clubroom, Old Union G3I0R. Building. Sec A. George, G4ESZ.

RADIO COM MUNICATION September 1977 715 Great Lumley (AR&ES)—Alternate Wednesdays, 7.30pm. Great Lumley Community Centre. Assistance with RAE and morse if required. All amateurs and SWLs welcome. Sec G8JLQ. Hartlepool (HRC)—Mondays, 7.30pm. Methodist Church Hall, Grange Road. Sec G3N WIJ, 73 Eamont Gardens, Hartlepool. Middlesbrough (PO ARC)—Sec G8CDP, 48 Grange Road, Hartlepool, Cleveland, Morpeth (Northumbria RC)—Now meets Thursdays, British Legion premises. Gambols, near Blyth. Sec G4AVO. Newcastle-upon-Tyne (Tyne and Wear Repeater Group)— First Wednesday in each month. Arts Common Room, University of Newcastle. Open to all amateurs and SWLs. 23 Sept (The group cordially invites all radio amateurs and SWLs to meet the RSGB vhf manager, Mr David Evans, G3OUF, at a question and answer session about the future of vhf amateur radio). 7.30pm. Refresh- ments provided. Sec G3URE. South Shields (SS& DRS)—Fridays, 7.30pm. Trinity House, Old and new members welcome. Sec G8BQF, 67 Lauderdale Avenue, Middlesbrough (Teesside Repeater Group)—Last Tuesday each month, 7.30pm. 196 Marton Road, Middlesbrough, Cleveland. All amateurs and SWLs invited but first contact sec Mrs Pauline Bland, G8MBK, 5 Belgrave Drive, Normanby, Middlesbrough, Cleveland. Two distinguished speakers attended a meeting of the Tyneside (TRS)—Mondays. 8pm. The Community Centre, Vine Wessex ARG on 20 May: Ken Alford, G2DX, talked on "The Street, Wallsend. Sec Alex Frazer, 35 Percy Street, Tynemouth. early days of wireless", and Dud Charman, G6CJ, gave his fascinating well-known talk on antennas. Left to right: Roy Scott, G2C21-1, club vice-chairman; G2DX ; Frank Hicks. Arnold, club president; and G6CJ REGION 19—RR D. S. Smith, G4DAX, 151 Hamper Mill Lane, Oxhey, Watford, Herts. Southampton (SRSGBG)—Second Saturday In each month, Acton, Brentford & Chiswick (ABCRC)-20 Sept (G3CCD as Lanchester Building, Southampton University; Wednesdays, the FOUT in France), 18 Oct (2m antennas). 7.30pm. Chiswick Trades clubroom. Kent Road; both at 7.30pm. AR G4CO M. and Social Club, 66 High Road, Chiswick. Sec G3GEH, tel 01-992 South Dorset (SDRS)-7.30pm. Lecture Hall, South Dorset Tech- 3778. nical College, Newstead Road, Weymouth. Details from G3Y WG. Barking (BR&ES)—Mondays (Constructional), Wednesdays Swindon (SD&ARC)—Alternate Wednesdays, 7.45pm. Clubroom (CCTV techniques), Thursdays (Informal). Morse classes Tues- above Coldharbour Public House, Blunsdon, just north of Swindon. days. 7.30pm. Westbury Recreation Centre, Westbury School, Sec G8K WC. Ripple Road, Barking, Essex. Sec N. Dowsett, 44 St Anne's, Winchester (WARC)—First and third Fridays in each month. Barking. 7.30pm. Antrim House, St Cross Road, Winchester. G4BKE. Cheshunt (CDRC)—New premises—Church Room, Church Lane, Wormley, Hens. Wednesdays, 8pm. Chingford (Silverton RC)—Fridays. 7.30pm. Friday Hill House, Simmonds Lane, Chingford E4. Visitors very welcome. Sec G4AJA. REGION 18—RR P. J. Fay, G3AKG, 5 Harland Way, The Glebe, Washington, Tyne and Wear NE38 7RB. tel 01-529 2282. Ealing (EDARS)—Tuesdays, 8pm. Northfield Community Centre, Durham (DUARS)—Alternate Wednesdays during term. Physics Northcroft Road, London NW13. Newcomers and old-timers very Dept, Durham University. All local amateurs are welcome to join. welcome. Sec M. E. J. Cummings, G8KPN, tel 01-997 5947. Talk-in by G4DUR on R5 or S20 before all meetings. Easington (AR&EC)—Tuesdays and Thursdays, 7.30pm. Easing- East London RSGB Group—Sum mer break until September. Do not forget "Small box of tricks competition". Build something into ton Village Workmen's Club. RAE and morse tuition if required a 2oz tobacco tin. Rules from sec J. Bundock, G4CJQ. (the club has a good RAE pass record). ATV can be received on Edgware & District RS —Slow cw under club call G3ASR/A now 625 lines. The club Is now equipped with an hf transceiver as well on 144.175MHz, Mondays 8.30pm, and first and third Thursdays as other gear. Sec G4C01. 7.30pm. Reports greatly appreciated. Sec G4BZY, tel 01-952 2495. Harrow (RSH)—Fridays, 8pm. The Roxeth Community Centre, Scott Crescent, West Harrow, Middx. Sec G4FBK, tel 01-864 1412. Havering (H&DARC)— Wednesdays, 8pm. British Legion Club, Western Road, Romford. RSGB Region 18 (NE England) Holloway (Grafton RS)-7.30pm. Holloway Institute, Archway Annexe, Highgate Hill, London N19. Sec G3ZKE. REGIO N AL LEC TU RE Ilford RSGB Group—Thursdays, 8pm. 50 Mortlake Road, Ilford. Details from D. T. Sapworth, G3YM W. Scarborough Lecture Theatre Northolt (British Airways European Division ARS)—First University of Durha m Monday in each month. Trident Club, Western Avenue, Northolt, Middlesex. This club is open to non-BA employees by invitation. (By arrangement with the Durham University Radio and Contact G3OUF, tel Amersham 21573 for details. Civil Aviation Electronics Society) Sunday net at 1100-1200gmt on 3.68MHz, listen for G3NAF or G3BEA. Co m mencing 6.30p m (sharp) Saturday 8 October Shelbourne (SRC)— Wednesdays 7pm-9pm (Electronics for 1977 beginners), Thursdays, 7pm-9pm (Club evenings). Shelbourne Speakers: Youth Centre, Hornsey Road, London N4. South Kensington (Baden Powell House Scout ARG)—Third Mr "Dud" Charman, G6CJ, with his famous "Aerial Tuesday In each month. 8pm. Baden Powell House. Queensgate, Circus" South Kensington. Mr B. O'Brien, G2AMV, Zonal manager Southgate (SRC)—Second Thursday in each month, 8pm. The Green, Winchmore Hill, London N21. Sec G4AEZ, tel 01-366 7166. All amateurs and SWLs welcome St Albans (Verulam ARC)-22 Sept (G3KFE), 27 Oct ("Early experiences of radio com munication" by C. Martin). 8pm. Market Talk-in by G4DUR on R5 and S21. Entrance on South Road Hall, St Albans. Second Thursday of month (Informal meetings). (A1050) Details from sec G4OUS. Details from G3AKG, QTHR, or at your local club Stevenage (S&DARS)-15 Sept ("Amsat" by G3R WL). 6 Oct (Zone C manager—G3MXJ), 20 Oct ("Intruder watch" by GS M, 3 Nov (Junk sale). 8pm. Canteen, Hawker Sidley Dynamics Ltd,

716 RADIO COM MUNICATION September 1977 Gunnels Wood Road, Stevenage, Herts. Talk-in on S20. Sec Bristol (BRSGBG)-26 Sept (Brains trust), 31 Oct (Geology of the G8KMV, tel Stevenage 54689. Bristol area), 28 Nov (Regional rep). 7-9.30pm. Small lecture theatre, UK FM Group (London)—Second Tuesday in each month, 7.30pm Queen's Buildings, University Walk, Cliften, Bristol 8. Sec G4FRG. for 8pm. Grove Park Hotel, Junction Bolton. Spencer Roads, Grove Cheltenham (CRSGBG)—First Thursday in each month. 80m. Park. Chiswick. The Old Bakery. Chester Walk, Cheltenham. 1 Sept (The Society President). Sec G3KII. Gloucester (SARS)—First Thursday in each month. 1 Sept (AGM). Chequers Bridge Centre, Painswich Road, Gloucester. Sec G3MA. REGION 20—RR G. Mather, G3GK A, 8 Hills Close, Keynsham, Weston-super-Mare (WsMARS)—Second Friday in each month, Bristol. 7.30pm. Room Lewis M2, Worle School, New Bristol Road, Worle. Bath (B&DRG)—Tuesdays, 8.30pm. The Crypt, Ascension Church, G3PQE. 35a Claude Avenue, Oldfield Park. Bath. Sec N. S. Cridland, Flat 3, Yate (Y& DARC)—First Saturday in each month, 8pm. G3RQN 30 Paragon, Bath. BA1 5LY. QTH. All welcome, including SWLs. Local chat channel S24, Bristol (BARC)—Tuesdays, 7.30pm. The University Settlement, 145.6MHz, 2100 Wednesday and Saturday. Further info from G8LGC. Barton Hill, Bristol 5. Sec G8KGE. Yeovil (VARS) —Thursdays, 7.30pm. Hut 101, Houndstone Camp Bristol (Shirehampton ARC)—Fridays, 7.30pm. Twyford House, (three miles W of Yeovil, off A3088, info at main gate). S20 Ern talk-in. Shirehampton. New members most welcome. G4B WB. Sec G3NOF.

Looking ahead Mobile rallies calendar

10 September—Scottish Amateur Radio Convention, Adam 18 September Peterborough Mobile Rally, Walton Secondary Smith Centre, Kirkcaldy. School, Mountsteven Avenue, Peterborough. Talk-in static n G3DQ W on 2m. Details from 17-18 September—N W Amateur Radio Convention, University of G3EEL. QTHR, tel Peterborough 62881 .65423. Lancaster. 25 September Harlow & D ARS Rally, Netteswell Comprehen- 25 September— Welsh Amateur Radio Convention Oakdale sive School. Harlow. Details from G3WUX, Community College, Blackwood, Gwent. G8FRG, G3YDI, QTHR. 15-16 October—Jamboree on the Air. 27-29 October—ARRA Exhibition. Granby Halls, Leicester. 2 December—RSGB AGM, IEE, Savoy Place, London WC2.

1978 2 April—Northern Radio •Societies Association Convention and Exhibition, Belle Vue. Manchester. Details from G8BCG or G4BVE, QTHR.

Contests calendar

18 September DF Final South Manchester 18 September 10GHz Cumulative (Rules In May issue) 1-2 October UHF (432MHz-2•3GHz) 8-9 October 21128MHz (Rules in June issue) 15-16 October 7MHz Phone (Rules in June issue) 23 October 70MHz Fixed October- November 432MHz Cumulative 5-6 November 7MHz CW (Rules in JunelJuly issue) 5-6 November 144MHz CW 12-13 November 2nd 111MHz The RSGB stand at the RNARS rally on 19 June, with Len 4 December 144MHz Fixed Nevvnham, G6NZ, the man behind the stall

Members of the Southampton University Radio Club alongside the 1929 Dennis bus, nicknamed the "Toastrack" and maintained and run by the engineering faculty of the university, at the Longleat Rally on 12 June. Left to right: C. Bryant, G3WIE, and xyl; C. Debney, G3ZY W ; R. Taylor, G4FDG; A. Lincoln, G4CIG, and yl; I. Mercer, G3ZER; M. Bayes, G4DIC; A. George, G4ESZ; J. Spicer, G8LJU; J. Old, G4D MY; F. Baldry, G810P; A. Ward, G8KGG, and R. Keech, G8M KL

RADIO COMMUNICATION September 1977 717 TS700G, TR7000A, Datong UC.1, Microwave Modules 500MHz counter, all as new, for sale to best offers. G8DLP, QTHR. Tel 021- 556 3324 daytime. rmembers' ads Multimobile G-whip, 101520 plus 80m (slightly damaged) and 160m coils, new price over £30, bargain at £16.50. MK Products factory assembled sstv PCBs, 5FP7 tube, almost finished psu, £38. Coder CR70A gen coy rx, £21. Prices include carr. G4BVH, QTHR. Tel 0273 504634. These subsidized flat-rate advertisements are accepted as a service Liner 2, fitted preamp. mic, Belcom R115E psu, manual, mobile to members of RSGB. They must be submitted on the Members' mount, mint cond, £115, no offers. Radio Com munication Handbook, Ads order form printed in alternate issues of Radio Com munication, 4th ad, £5. 2m 5:03 whip, hinge type, no base, £3. Smith. Tel Worc or on a postcard similarly laid out. Each must be accompanied 354679. by a recent Radio Communication wrapper addressed to the Latest model IC240 with IC3PA psu, all mobile fittings etc. 6-el advertiser, as proof of membership, and a remittance by postal quad. All just three months old, still under warranty, hardly ever order or cheque for 75p (stamps not accepted). They will not be used, first £200 secures. Buyer collects or deliver at cost. GW3CBA, acknowledged. Those not clearly worded or punctuated will be QTHR. Tel Barry 737793. returned. No correspondence concerning this service can be Heathkit SB200, £150. Hy-Gain 203BA BN86 balun, £50. G4DJC, entered into. QTHR. Tel 0245 69034. The closing date for each issue is the 1st of the preceding month, FT277 Mk2, exc order, £290. Heathkit 5E3300, SE1400, completely but no guarantee of inclusion in a specific issue can be given. overhauled and revalved, exc order, £180. Francis and Lewis 40ft Valid advertisements not published in the issue following receipt lattice tower, as new, £60. Devices Sales Ltd Heatpen recorders will be held over until the next issue. with handbooks and paper, £150 each, G5UG, QTHR. Tel 0934 25961. Trade or business advertisements, even from members, will not Datong UC ,1 up-converter, £80. Yaesu FR1011:1D digital rx. fitted be accepted for Members' Ads but should be submitted as classi- extra 5MHz xtal, £380. Reason hope to need tx. Could deliver fied or display advertisements in the usual way. Traders who are reasonable distance. Riminton, 17 River Mount, Walton-on-Thames, members must enclose a signed declaration that the items for sale Surrey. Tel Walton 20898. or wanted are part of, or intended for, their own personal amateur FTDX500 tx(rx, 560W, p.e.p. a.m..'ssbicw, spare valves, KW E-Zee match, SWR50A, 501.1 dummy load, Instruction manuals, £285. station. The RSGB reserves the right to refuse advertisements, and S. Williams, 7 Oddfellows Street, Scholes, Cleckheaton, W Yorks accepts no responsibility for errors or omissions or for the quality f3D19 5NX. of goods offered for sale. Advertisements may be edited or abbre- Pye Monoscope tv test card generator, test card G, in 511 by 19in viated as necessary. blower cooled rack, wkg order, £25 ono. Prefer buyer inspect and collect. G4FEV, QTHR. Tel Bedford 64148. Post to: MEM BERS' ADS, RSGB, 88 BROO MFIELD RO AD, Twenty-six 4m Cathodeon xtals made to Pye specs for Cambridge CHELMSFOR D, ESSEX CM1 1SS. and Bantam, £1.25 each or £20 lot to clear. 4-el 4m Jaybeam, boxed, used one contest only, £8. Pye F30AM base, £150. Setak. Tel Do not post to RSGB HQ or Advertising Representative. Caterharn 47892. Liner 2 ssb tx or. with latest PA1 preamp, £120 or exchange for IC202. 90W a.m, tx, modulator and psu, £20. G8KKA, QTHR. TC10 tx, mk2. TC7 rx, mk2. Magnum 2 linear. 10-el Jaybeam. All exc cond, with circuit diagrams, instructions, etc, deliver 50 miles, FOR SALE £225 or will separate, buyers to collect. Wanted: quality hf taira. G8KD W, QTHR. Tel 08277 2348 evenings. D FM:60MHz, 50mV sensitivity, 100Hz res, 6— digit led, sup leading Trio JR500S rx, 80-10, no-mods, exc cond. box, £40. Wanted: zeros, prof pcb, case 8 by 2 by 5, £42 ono. Buyer collects. Tel mobile fm;a.m. rig, Cambridge. Storno or similar with several ch 01-648 5895. control gear, must be wkg 2m. Les Boddington, 1 Davenport Drive, Complete station comprising Yaesu FT200, FP200, mic, type D Castle Vale, Birmingham 35. Tel 021-748 7569. morse key, home-brew swr meter, 1pF dummy load, 25ft mast and Liner 2, preamp. R115E power supply, £140. TR2200G, 13ch, nicads, various antenna bits and pieces incl makings of TA31, £245. £130. 2m fm pa, 1W in. 18W out, preamp, £25. Lafayette HA600A G3UAO, QTHR. Tel 076-31 5245 evenings. gen cov rx £35. Microwave Modules 2m converter. 2-4MHz if,, £13. Yaesu FR101D, manual, mint cond, 2m ground plan antenna and All ono. G8FSL, QTHR. Tel 01-360 5221. two 301t galvanized steel poles. £320 ono. Buyer collects. Must sell, moving. Whittingham, 351 Woodham Lane, New Haw. Weybridge, Pair Pye Pocketphones, nicads, charging pcb, RB2 xtals, tx output 400m W, some spares, £33.50 plus post. 2m 40673 mosfet Surrey. Tel Byfleet 43124. FRDX400, ideal swl ru. 10 to 160m, exc cond, very little used, £135. preamp. £4. 1750 xtal toneburst, £5. All good clean wkg cond. G4E0 W, QTHR. Tel Rornsey (Hants) 512475. Martin Oakcrott, Kingston Lane, East Preston. Sussex. Tel 0843 CR100, clean, oh, must be collected, £15. Xtals: HC6U 33.200, 20592. Shack clearance: G3HT A ht amateur bands rx, Electroniques 51-900, £2 each; HC18U, most wire leads, 10-250, 10-300, 10.800, front-end, 0-multiplier etc, £45; H W7 3-band tars, still under 33-200, 33.375, 33 -440, 34 -4825, 34-825, 35.000, 35.658, 37.325, 40.000, guarantee, £50; 0X4OU with vfo, exc cond, £40; Panda Cub tx. 43-333, 44.600, 45-000, 74.825, 78 .525, 80-506, 81.506, 84.506, 88.304, 88.975, 90.833, £1 each. G3HBG, QTHR. working cm only, £15. G4FEQ, QTHR, Tel Leeds 863361. SS M Europa, £70. MM 70cm to 2m converter, £13. Tripler, £13. FR5OB rx. vgc, £65, G8KNO, 55 Greenway Rd, Taunton. Tel Yeovil Joystick UFA, system J, unused, £34. Pye Cambridge AM1OD hi- 25129 evenings. band. unmocl, complete, £20. G4FGJ, QTHR. Tel Oakley 3304. !corn IC202, very nice rig, little used, as new, £135. G4FAI, QTHR. Save £40. Nearly new Microwave Modules 70cm transverter, Tel 01-807 3537. MMT432;28, together with Jaybeam MBM48-el Multibeam, £90 the K W201 amateur bands rx, 1-8-28.8MHz, double cony, ssb, a.m., ow. pair. Two new Sylvania 6JB6 pa tubes (Drake NCX etc), £5. Tyler, xtal controlled first mixer, switched usb, lsb, 1kHz readout, 1kHz 94 Alexandra Ave, Luton, Beds. Tel 0582 25519. xtal calibrator, handbook, vgc, £110. Revill, 74 Setworthy Drive, FT101, including fan, est spkr, mic, exc cond, £275. HQ1 Minibeam, Stafford ST17 OPP. Tel Stafford 63387. Stolle 2010 rotator, £65. 8Y/2m Vagi, brand new, £8. Dual swr TH3JR Thunderbird 3-el, 3-band beam, good cond. £70. G3NUG. bridge, rf field indicator, with traps, terylene guys, shackles, £15. QTHR. Tel Radlett 4435. Buyers collect. G4CEU. QTHR. Tel Southend-on-Sea 526431. KP202, fitted SO, S20, S21, S22, R6, R4, with extra xtal R7, nicacl Pye PTC331 20W a.m. tx with fm using Burns phase modulator, batteries, leather case, helical whip, £100 ono. QM70 transistor 2n1 vxo for most 1m channels, £20. Two 2m to 70cm Bay 96 varactor transverter, 2W output, 12V supply, £40. G4CLA, QTHR. Tel 061-370 fripiers, £10 each. 8MHz Emu vfo, £8. Marconi TF390G sip gen, 3160. 10-150MHz, £10, Communication receivers: AR88D, £50; BC342M, Datong filter, model FL1, unused, £40. Storno Viscount, 4ch, 145, £35; both with fm discriminators, spares and handbooks. Micro- S20, 522, R7, fitted preamp. £35. G3YJD. Tel Watford 45133. wave Modules 70cm converter, 28-301.f., £18. DL6S W 2m converter, Grundig TK reel-to-reel tape recorder, with mic and tapes, little 28-30 if., £10. 1-15W 2m converter, 6-8 O., £8. Rs atu, 3-xtal calibrator used, almost as new, £20 ono. Prefer buyer collect. G3MA, QTHR. and preselector, £10. G8EZJ, QTHR. Tel Reading 476873. Essex Telecoms 2m colinear, £20. Mosley RD5 amateur bands If you want a JR500S with top band, phone 01-460 7148 and ask for swl trap dipole, £10. Bantex 2m mobile whip. £5. Heath code practice Phil, G8MDA, and have £40 ono in used oncers handy, or write to oscillator and key, £7. Morse records, beginners, advanced and 97 Nightingale Lane. Bromley, Kent. check record, £3 set. G8HPA, QTHR. Tel 078-73 71842.

718 RADIO COM MUNICATION September 1977 BC348 6-band rx, £25. Professional nuvistor converter, 145MHz, Heathkit HW101, £200. SB102, £135. Depth sounder, £35. Hustler £12. Ancient 144MHz tx, £10. Each with mains psu and sets spare whip, 15, 20, 80, £30. Q-multiplier, £7. HP13, £25, HF dummy load valves. Many xtals, random frequencies, all 50p. SAE for list. G5UM. wattmeter £35. AV-3U millivoltmeter, £12. Some Fleathkit ssb filters Tel Leicester 416473. and hf tx¡rx xtals. Offers. G4BZU, QTHR, Tel Cheltenham 26530. K W202, £175. KW Vanguard, £30. 1340, £15. Heathkit dummy load, Yaesu FRG7 rx, nearly new. £120. Sommerkamp FL200B tx, £115. £5. Tel Cheltenham 20409. Owner renewing gear. G4FVR, QTHR. Tel Scarborough (0723) Yaesu Musen vfo FV400S, new cond, £40 ono. YD844 desk mic, 74539. £10. 18AVT vertical, £35. Graves, G4BCP, Woodpeckers, Hillside PF1 tx/rx, RB4, above average cond, new batteries, charger, and Road, Rothbury, Northumberland. Tel 066-92 20846. ac psu for rx. Bantes 58 432MHz whip. KW E-Zee match. Ac psu. FT200, FP200, 80-10m, tx/rx, vgc, £230. HQ1 minibeam, £35. KW 6-3V 3A, 300V 70mA. Offers. G3XLL. Tel Mellis 596 evenings or E-Zee match, £15. G4DFS, QTHR. Tel Barnsley 790386. weekends. Som merkamp FRDX500, exc cond, £150 ovno. Buyer must test Liner 2, £85. Hy-pain 18AVT.WB, £40. Stolle rotator 2010, £30. and collect. Kavanagh, 5 Nada Road, Highcliffe, Christchurch, Bantex 2m whip and mag mount, £10. All as new. Collect and Dorset. Tel Highcliffe (042 52) 6914. inspect. G and D 2m converter, 28:30 if., ac supply, £10. G3OSH, H W202 fm rig with Heathkit psu and xtals for tx/rx on SO, S20 and 22 St Peters Close, Horton, Nr Ilminster, Tel Ilminster 3349. rx only on S21, 522 but room for more, mint cond but must sell as 70cm PA 2X4CX250B commercial with filters, £35. Coder AT5 tx hopefully going hf, £85 ono. G8JOH, QTHR. T28 rx switching unit and dc psu, exc cond, £40. AVO8 comp with Storno COL662 uhf fm 6W tx/ru, control box and access tone, prods and leather case, £50. 2m pa 150W, £20. antenna, xtals fitted for RB4 and SU8, up to 12ch available, £75. Wanted: For collection 2C1 tx;rx. G8BSR. Tel Telford 460096. Tel Ipswich 0473 310442. Tired of talking to yourself? Try my auto-reset repeater timer, Mains transformers, oil filled: 1,185V-0-1,185V, 360mA, £8. 500V- times multiples of basic time period, marked by three "pips". No 0-500V 250mA, 3 x 6-5V 5A, £4. 230V-0-230V, 2 x 6-3V, 6A, £3.50. connections to your rig requirec1-5aA quiescent current. G8KKP, Mains psu, stabilized, suitable for Liners or fm equipment, adjust- QTHR. able from 8 to 18V dc, 3.5A, £20. SAE enquiries. Carr extra. G4DFE, Original manuals for AR/38-D. HRO 527, BRT400'402, CR300, All OTHR. good cond; valves 832, 832e, 866. All items £1 each incl post. Single meter swr bridge SWR10, £4. Pair Eagle FR65 10W 8f) G2QY, QTHR. Tel Cheltenham 20105. spkr chassis, £8. Wanted: FLDX400 tx. SP400 spkr 444 mic. Heathkit HD-10E electronic keyer, perfect, with manual, £25. G8KAX, QTHR. Class D wavemeter with book, mains, £8. Medco 1p filter 75f.), Business forces ORT: FT200B with FP200, as new, less than 10 unused, £5. GW3YUC, 30 Wern lsaf, Penywern, Dowlais, Mid hours use, £230. TA33JR with AR22R, £49. Liner 2, fitted preamp. Clan). £105. G3ZVC module with hl preselectoridriver components, £50. Give-away prices. I have a large quantity of xtals, microwave G2DAF tx mk2 wkg fb 10-80, £40. Tel Reading 694761 evenings. components, rtty equipments, Pye tx:rxs 4m, 2m, low, medium and FT200, psu, vgc, full 10m coverage, new PAs and driver, £200. ITT high power, SL600 ICs and many other items to clear. Send sae for Starfone FM10 fitted S20, S22, base station psu/spkr, sleeve and large list. Shepheard, G W3XNS, Bryn Tawet, Belmont Road, mic, full service manual, £70. G3IKN, QTHR. Tel 0344 26197 after Bangor. 6pm. FT200B, showroom cond, little used, £255 ono. Belcom Liner 2 Pair ch walkie-talkies, suitable conversion 28MHz, £12. Z-Match mk2, vgc, £130. 18AVT WB plus radials, £40. CT373 test set incl atu, £15. Pair Richmond teak bookshelf spkrs, £6. Wanted urgently: at osc, valve voltmeter and distortion meter. lovely cond, £25. Trio TR2200 or similar 2m tx/rx. Electronic keyer for 'MM. G4CRH, G8JFV, QTHR. Tel 08867 685. QTHR. Tel Chipping Norton 2724. Heathkit HW100 five-band tx/rx, mint cond, with ac power supply, Kimber-Allen 37 note keyboard, gold dp contacts, pcb, unused, spkr, Shure mic and compressor amplifier. Excellent complete £30. Carlsboro Wah-Swell pedal, £12. Valve 2m converter, requires station. £198. G3WY, QTHR. Tel Evesham 45497. 300V and 6-3V, £3. Two 10H chokes, £1 each. Four 5,000eF 35V TRIO 7200G, mic, power lead, car mount, manual; also PS5 mains electrolytics, 50p each. G8GNI, QTHR. Tel 01-361 9364. power supply/digital clock: 58 whip; all six months old and perfect; Collins 455kHz xtal filters, 500Hz bandwidth, £10. DX100U with 20% off list prices. GW3YVC. Tel Cardiff 755190. spare valves, manual, £35. BC221 with mains psu, manual, £18. TS500 P5500 80-10M, 180W pep, ssb-a.m. exc cond, £150. 6146 valves, new, boxed, £3. HRO BS and GC coils, S-meters, most G4FBA, QTHR. Tel Pontefract 85941. other parts. G3AAK, QTHR. Tel Ringwood 3078. Property late G8DY0 FT200 FP200, £240. Europa 2 MTV. £80. Bantam, fully wkg on 2, good cond, £40 ono. ZVC ssb with pre- TR7200G and vlo 30G, £190. Trio mc50, £10. Hansen SWR3, £5. select, pa, and psu wkg on 80m and 20m, 100W out, £90 ono. Pye a.m, base station. 6 slats, £15. Tuning fork strobe, 125Hz. Mini- G4FA W, QTHR. Tel Ipswich 58815. beam 10-15-20, £25. Lattice tower 30ft 4-el Yagis, ah i tube, 2in odd Marine vhf tx/rx, 25kHz channels, ITT type STR20B, 12,24V dc lengths, offers ? Tel 0502 63022 evenings. 10W, comp with manual, handset, channel xtals, £140 carr paid. 75ft lattice mast, six sections, £150. Pye compact charger SU8, Valves: QVD8-100B. £3.50; QZ06-20. £1.25; 59254M, £2; 1625, £1. £50. Starphone SUB, RB4 charger, £65. Pye Vanguard (tx only) SO, Racal Mobical u¡I ssb 10-7MHz filters, £20 pair. G3JMJ, QTHR. S20, S22, S32, R3, R6, R7. 144.4. 24V, mains psu, £30. All negotiable Tel 073-271 3467. (carriage extra). G8AXLI, QTHR. Debenham 215. JVC Nivico TD-694 stereo tape deck, as new, in maker's box, RAE home study course, £9 ono. Details from G8JBK, QTHR. Tel swop mobile rig, ht or vhf or why ? 18AVT with radials and UR67, Colchester 230318. £35. G4DRI, QTHR. Tel 01-440 7137 after 7pm. Heathkit SB303 ht rx fitted with optional cw and a.m, filters plus Liner 2, fitted with 2m rx preamp and 10m tx preamp for use with SI3600 matching spkr, £230 ono. G8JBK, QTHR. Tel Colchester 0M70 70cm transverter, QM70 28/432 transverter, 10W output, 230318. audio speech processor, plugs, cables, manuals as supplied, Trio TX599 JR599 and SP599, £350 or why? Need FT301S or buyer collects, £140 ono complete. G4FAZ, QTHR. Tel 030-57 71053 similar 12V low power rig. G8ETR, 43 Freemantle Road, Bagshot, evenings. Surrey. Tel Bagshot 74576. Yaesu FRG7 gen coy rx, mint cond, sale due to bereavement, Hallicrafters S27 RX 27-143MHz manual, £38. SR42 tars wkg 2m, £130. G4EJH, QTHR. Tel 0272 843897 evenings. £28. IOXY 2m Yagl, £16. PC5 audio amp, £4. Want kw E-Z match, Complete homeimobile station: Drake TR3, RV3 vfo, ac psu, TA-31/32 triband beam. G4AFY, QTHR. Tel Kidderminster 63358. spkr, DC4 psu, mobile harness, mount, Hustler antenna, resonators K W2000A, mains psu, manual, good cond, £160 ono. G4EHF, for 1015,20m, mic, owner buying new Drake-Line, £300 ono. Tel QTHR. Tel Brighton 508136. 0474 4694. Creed 7B + power supplies, £25. Terminal unit AN:UR8!A, £20. Drake T4XC, R4C 160 to 10m, W WV 10MHz, 15MHz FL1500, AC4 Datong frequency agile filter, little used, £40. Yaesu FRG7, as new, psu, mint cond, recently realigned, £800 complete. Heathkit SB200 £145. Linear 2 .< 813 (G2DAF type), £40. GW4ACO, QTHR. linear, good cond, £180. Buyers collect. G3SVH, QTHR. Tel 0922 FT250 with ac and dc psus, vgc, £170. Heath SB220 2kW linear, 414524. mint, £250. Hy-gain TH3 mk3 with balun, boxed, £50. Magnum 2m K W200B, first class cond, ac pas. £205. Class D wavemeter, 1.8- transverter 200W, vgc, £70. G3SPJ, QTHR. Tel 01-311 8405. 8-0MHz. £7.50. Nombres sig gen £5. Martin 3-speed 2-track tape Fiat Hallscrieber 2.50, portable Haliscrieber tx/rx 5.00, RAK 15600 recorder, £8. G4CMU. Tel Burgh Heath 54497. kHz 2.00, Decca projection tv oft ers, S27 rx mains/6V otters, ATE 6A Microwave Modules MMT144:28 2m transverter, with leads, as distortion rx 6.00, 7,TR2 reperf 3.00,18 tapetx 1.50, R1475 rx mains'12V new, £75 ono. G8LYT, QTHR. Tel 061-428 8594. 6.00. Collect. SAE list. G3DSK, QTHR, Skyfon superhet transceivers, 3ch, 1W, 8 transistors, 1 ic, stalled K W2000B with matching spkr.ac power supply, like new, almost 11 m channel for conversion to 10m, as new, cost £80-£90, cash unused, £210. Heath SB610 monitor scope in same cond, £60. required. Nigel. Tel 01-508 4444 (Loughton) daytime. G3KAS, 73 Rawcliffe Lane, York. Tel 0904 27123.

RADIO COM MUNICATION September 1977 719 Eddystone 880 high stability communications rx 30 x 1MHz bands W ANTED 0.4-30-6MHz, good cond, £180. R1155 rx converted 240V, £20. 27ft 5U4G valve, 8uF electrolytic capacitors for CR100 rx. Good price antenna mast, tubular steel base, tilt-over lattice, aluminium pole paid. G8AED, QTHR. top section, £20. G8JDE, QTHR. Tel Sambrook 375. Drake 28/213Q or rx of similar performance, amateur bands or gen FR508, £75. PR40, £8 ono. Two mains transformers, 300V at 15mA, coy, will collect. Power calibration chart for Asahi swr and power 300V at 15mA, 4V at 2A, 4V at 0.2A and 4kV at 2mA, 2V at 2A, 2V meter ME-IIN, will copy and return, all costs refunded. G4CHL. at 2A. £1 each. Two tc caps, 0-1iF 7kV, 15p each, Resistors 1%. QTHR. Tel Gravesend 68233. carbon film 2W 70, 30k0, 33k0, 40k0. 2p each. 120(2 ww1 W,I.p each. Prop pitch motors and 50Hz Selsyn motors. G8TR, QTHR. Enam copper wire 80p/lb. sae for info Sept only. All items + carri- TC355D frequency counter. KW-VF0/46 for KW200013. Datong age. G4DSE, QTHR. clipper. Technical Associates peak-notch filter, bandpass filter, Racal ssb demodulator unit for use with RA117 rx 100kHz Input audio compressor. G2FUU, QTHR. Tel Nazeing 2274. less outer covers, £20. 1-4MHz le filters 2.35MHz bandwidth in Faulty CR100 or B28 rx, any cond acceptable, even incomplete, sealed unit containing six crystals type 6hu. £3. All plus carriage. state price. Bentley, 27 De Vera Gardens, Ilford, Essex, Tel 01-554 G3ZDB, QTHR. Tel Epsom 24814 after 6pm. 6631. FT101 160-10m inc 27MHz cb, cw filter, phone, SP101. Yaesu mobile Disabled swl seeks mach filters for 51..14. I seek minute all-band tv and desk mics. Osker SWR200. All fb cond. £320 ono. RCA AR8516L for tvi monitor and AR88 S-meter. G3JZV, QTHR. Tel 0702 691791. com m rx 15kHz-30MHz less psu and cabinet, boxed, new spare Mast, Versatower type P60 or W60, galvanized or equivalent. Rotator valves included, £100 ono. G3TZL, QTHR. Tel 07017-22384. type CD44 or Ham 2. Triband 3-el beam, type TA33 Jr or equivalent. Microwave Modules MMC144/28L0 converter, bnc sockets, as G4AXT, QTHR. Tel 0509 31005 after 5pm. new, £13.50 plus post. G8AYY, QTHR. Yaesu FTV2.50 2m transverter or 2m Europa transverter for F11016 ta/rx, must have manuals. G2BNZ, QTHR. Tel Bolton 654749. Midy VN trap dipole 80-10m, £30. HQ1 Mlnibeam with spare elements, £35. Liner 2 with preamp, mobile mount 10-el Vagi, SSB 80m tx/rx suitable for mobile/portable operation, preferably 30/50W 12V. Also antenna. G4CKA, QTHR. Tel Macclesfield 25154. Halo, ac psu, £110. Tech Ass bandpass filter, £13. Buyer collects. G W3YPF, QTHR. Tel 0248-680 630. Creed 7B, silence cover, Creed tape reader. All replies answered. G4AEI, QTHR. Tel Reading 85123, ext 7614, during wkg hours. Satellit 2000 gen coy rx, with ni-cad and ssb unit, mint cond, £100 Two UEL Cubs (Pocketset 467) 12-5kHz, with batteries and ono the lot. Easton. Tel North Shields 70429 after 6.30 pm. charger. UEL F4B70 base, 12.5kHz if possible. G3NNY, QTHR. Tel EC10 mk2, mains psu and battery pack, fitted Burns FMD1 fm Luton 0582 412513. detector, £125. HRO-M gen coy rx, model RCE, 2-30MHz, psu, Panoramic display unit, Eddystone EP20 or EP15, or why? Must unmodified, £25. Poulter, 119 Aragon Road, Morden, Surrey. Tel be first class, no junk. G2HIX, QTHR. Tel 0246 6215 (Chesterfield) 01-330 3031 after 6pm. evenings. Liner 2, PA3 preamp, mobile mount, manual, inc delivery UK main- FT75. Spares for Cambridge AM1OD spkr and mic. GW3ACF. Tel land, £125. 2m 6-el Q6 quad, 10 months old, £14. Complete photo- Briton Ferry 812475. graphic Cibachrome equipment, Inc M301 enlarger, lens etc for Transformer for linear, size no object, 2kV ac to 4kV ac at 300mA prints from slides, as new. £175. G4CHD, QTHR. Tel Cheltenham plus. Valves for linear: QY5-500 3-1000Z, 4-1000A or why? G3CWI, 53178. QTHR. Tel Leic 415501. Trio JR500S rx, 80-10m built-in spkr, opposite sideband xtal fitted, S8102, must be mint, prefer factory built. Price and details to exc cond, with manual, £65 ono. G8LYF. Tel Tedburn-St-Mary G W3TM P. QTHR. Tel 035-287 846. (near Exeter) 485, Antenna couplers or multi-couplers, one antenna in, several out. Atlas 210X, European model, plus noise blanker and •ac psu, Loan to copy or buy manual for vlf rx 881-M, good price paid. HP431, superb performance for only £425 complete. Buyer inspects and 432 or similar power meter. Fletcher, 62, Moorbridge Lane, Staple- collects Cambridge area. G3NAC, QTHR. Tel 0954 60584. ford, Nottingham. Tel 0602 397446. Eddystone EC10 mk1 rx, £35. 18AVT/WB, £37. Buyers collect. Kokusai filter, type MF455 15CK with sideband xtals if available, Gibson, 1 Tamar Gardens, Walney Island, Barrow-in-Furness, urgently required. G3AMF, QTHR. Tel 01-989 9224. Cumbria, New awl requires amateur bands rx for about £50. Service informa- Creed 7B printer, vgc. 50 baud synchronous motor, £25. Electronic tion urgently required for Philips GM5655 scope, will copy and keyboard unit, 54 key, uncoded, £8. G4DUM, QTHR. Tel Crayford return if required. Bob Enright, 23 Gorham Drive, Tonbridge, Kent 526460, TN9 2DU. Tel Edenbridee 5231 wkg hours. Marconi Elettra short wave rx, 150kHz-30MHz, provision for mic or Redifon GR410 ssb ta/rx (military C14 version). Plug-in if, unit tape deck, modified for ssb or a.m., complete with manual, £60. type A620413. Audio unit type 6203A. SSS generator/demodulator Green L, Davis 2m te, 20W a.m., 12V or 240V, with 70cm adapter, unit type 6202A. Must be in good wkg cond, GR410iC14 or GR410T comp with Shure 201 mic, £50. G5SN, QTHR. Tel Southend 554846. for spares. G3UCT, 27 Glen Road, Fleet, Hants. Tel Fleet 6998. FT101, 80-10m, exc cond with Osker SWR200. £220. Pair 6HF5s Early books by John Scott—Taggart. Early horn speakers. Eddy- with bases. new, £5. Pair QQV6-40s with bases, £8. G3i1MB, QTHR. stone 6-pin shortwave plug-in coils. 10-stop bandset capacitor. Tel Lowestoft 69321. 0.0002 slow-motion reaction capacitor. Eddystone 3(2 spkr in round FTDX560 with fan, dynamic mic and Datong rf clipper, all vgc. die-cast case. Brown's type "A" headphones. Early wireless G4BYK, QTHR. Tel 0482 811386. magazines. Early Telsen components. N. Richardson, 2 Edna Eddystone 880 .5-30.5MHz, 30 bandspread ranges, unique precision Road, Maidstone, Kent. receiver, complete manual, £75. 5ft 6in rack on rollers, £3. Wanted: Pye a.m. Bantams plus battery chargers and rechargeable/dry for overseas amateur rtty printer 4-row keyboard. ST-6 tu afsk ose. battery cassettes, any band considered. Manual for R43 mk2 ground- No junk please. G8LT QTHR. Tel 032-732-321. to-air tx/rx. Your price paid. G3ZDG, 40 Midsummer Meadow. RA17 exc cond, cabinet, £300 ono. Pocketphone PF2FMB R6, SO, Inkberrow, Worcs. Tel Inkberrow (0386) 792933 after 6pm. £55 ono. Bantam R6, S20 £30. Ranch Cambridge 4M a.m, comp Ayo valve characteristics meter complete with manual and in good batteries, £25. Wayne-Kerr video oscillator 10kHz-10MHz, £12. wkg order. Tel (0533) 552809. Solartron double-beam scope with handbook, £30. Wanted: Bird Atlas 215X or 210X. G3VH A, 2 Church Avenue, Clent, Stour- UHF elements UHF/SHF attenuator. G8ANZ, QTHR. Stonehouse bridge, W Mid. Tel Bellbroughton 730484. 4123. Sig gen TF144G, Avo8, vtvm No 3 CT208, Ayo valve tester CT160, Telford TC9 te. mixer vfo. A3 xtal or vfo F3, vio; TC7 mk2 te, with wattmeter absorption rl No 2 CT211 or CT417, mains psu for BC221- G8AEV mk2 2m converter, A3 Al, A3J. F3, buyer collects, £60 ono. Ak. External cond unimportant provided cheap, complete and G8FOR, QTHR. accurate. G3UCT, 27 Glen Road, Fleet, Hants GU13 9QS. Tel Fleet Versatower P60 with Mustang antenna and TR44 rotator, £365. (02514) 6998. Atlas 210 with de-luxe mobile mount and antenna matching tran- AR88, must be unmodified and in good wkg cond. Will collect up to sistor. £375. All items few hours use only and In new cond. Carr 50 miles personally, or arrange collection from Northern England. extra. J. L. Barry, 13 Mill Rise, Bourton, Gillingham, Dorset. Please state price. John Winter, 122 Threewells Drive, Forfar, K W2000B and ac psu, exc cond, recently checked by manufacturer, Angus, Scotland, Tel Forfar 4671. £200. Mosley V-4-6 trap vertical antenna, 10-40m, buyer collects, £28. New 4CX2.50B and uhf base. HF dum my load, noise bridge, Pp G3MCA, 1 Mosslea Road, Orpington, Kent. Tel 0689 56497. filter. 2/10m cony. For sale: morse learning course, records and FT200B, FP200B, plus Yaesu ptt mic, perfect cond, very little used, books, £2. Richardson, 30 Westbury Ave, Southall, Middx. Tel buyer collects, £280. G4BQV, QTHR. Tel Horndean (0705) 592629. 01-575-1454 after 6pm. H W12.+IW32 spare valves complete set, brand new and unused, Eddystone 888A nc. Codar AT5 tx, CT53 sig gen, state price and includes two pa 6GE5s, £15. DC inverter psu G3LGK type, suits condition. Manuals for CR100 rx, CT212 test oscillator, CT375 bridge. H W12/1-1W32'K W2000, £12. G4BP W, QTHR. Tel 0283 813395. Buy or borrow to photocopy. G4DS K QTHR. Tel Wakefield 72383.

720 RADIO COMMUNICATION September 1977 RSGB QSL BUREAU SUB-M AN AGERS (At 1 September 1977)

G2: J. W. Russell, G2ZR, 55 Holcombe Close, G4BAA-BZZ: R. F. Rawlings, G3WBV. 74 The Lindens, Bathampton, Bath BA2 6UP. Fieldway, New Addington, Surrey CRO SEL. G3 and G4 two-letter E. G. Allen, G3DRN, 30 Bodnant Gardens, G4C A A-CZZ: P. Jobson, G3HLF, 41 The Avenue, calls, G5 calls: London SW20 OUD. Gravesend, Kent DA11 ONA. G6 calls; G8 calls: Mr & Mrs A. J. Mathews, G6QM, 62 Ashlands G4DAA-DZZ: D. Buckley, G3VLX, 16 Wood Ride, Pelts Road, Hesters Way, Cheltenham GL51 ODE. Wood. Orpington, Kent BR5 1P X. G3AAA-DZZ: C. A. Bradbury, BRS1066, 13 Salisbury Avenue, G4EAA-EZZ: P. C. Barry, BRS22730, 32 Rutland Avenue, Cheltenham GL51 5BT. Sidcup, Kent DAIS 9DZ. G3EAA-HZZ: S. L. Newport, G4DEV, 101 Elibank Road, G4FAA-FZZ: Mrs A. R. Burchmore, G8LXK, 49 School Lane, Eltham, London SE9 10J. Horton Kirby, Dartford, Kent DA4 9DQ. G3IA A -KZZ : P. Lumb, G3IRM, 14 Linton Gardens, Bury St G 4G A A-GZZ : B. R. George, G3Z0H, 43 Magnolia Drive, Edmunds, Suffolk IP33 2DZ. Biggin Hill, Kent. G3LAA-NZZ: C. A. P. Henderson, G4FA M, 76c The Avenue, GB: C. Turner, G8NL, 56 Sunny Bower, Tottington, Beckenham, Kent BR3 2ES. Bury, Lancs BL8 3HL. G30AA-PZZ: J. H. BrazzIII, G3WP, 43 Forest Drive, Chelms- GD: W. P. Wald, GD3G0X, 1 Mount William, ford, Essex CM1 2TT. Summer Hill, Douglas. Isle of Man. G3RAA-RZZ: Mrs C. Pope, G4CMM, 136 Ridgeway Drive. GI: R. R. Parsons, GI3HXV, 45 Erinvale Avenue, Bromley, Kent BR1 5DD. Belfast BT10 OFP. G3SAA-TZZ: E. G. Allen, G3DRN, 30 Bodnant Gardens. GJ: L. D. Woolf, GJESA AZ, 57 Elizabeth Avenue, London SW20 CUD. St Brelades, Jersey, Cl. G3UAA-VZZ: M. Newton, G3UK W, 2 Marlowe Court, Gar- GM: D. R. Macadie, GM6MO, 11 Marchmont Road. forth. Leeds, LS25 1PR. Ayr KA7 2SB. G3WAA-XZZ: F. G. Rylands, G2VF, 39 Parkside Avenue. GU: W. E. Butt. GU2FZC. "Meo Voto". Green Millbrook, Southampton. Hants SO1 9AF. Lanes, St Peter Port. Guernsey, Cl. G3YAA-ZZZ: H. R. Boutle, G2CLP, 14 Queen's Drive, G W: J. L. Reid, GW3ANU, 28 Waterston Road, Bedford. Cardiff CF4 2SS. G4A A A-AZZ: C. Johnson, BRS31379, 118 Harvest Road, SRS anl A D. Bourne, G4CY W, "Roughways", Chub Smethwick, \Marley B67 6NG. numbers: Tor, Yelverton, Devon PL20 6HY.

1-10,1VED211. "Jilloetp" tbt trettb 1R-(g f:TI RS GENERATORS anb proinb gntennac ic=s AT KEENEST PRICES! Send for HANDBOOK containing full details of Antennas and 300-4000 W ATTS AC, 6-24 VOLTS DC other technical information. 33 pages 50p. Refundable upon INCL. THE NE W E3S00--1151230V AC & 12V DC purchase of Antennas. CO OKERY BOOK SO ME ANTENNAS £2.25 Inc!. Postage Mustang 3 Elements, 10, 15 and 20 metres .. £108.00 MICRO WAVE TA-33 Jr. High Power Model Incl. Balun LEADING MAKES OF MICROWAVE OVENS FROM £199 inc. VAT 3 Elements, 10, 15 end 20 metres .. £98.50 TA33 Jr. 3 Elements, 10, 15 and 20 metres .. £85.00 KEE NEST PRICES INCL U DE U K DELIVERY TA32 Jr. 2 Elements, 10, 15 and 20 metres .. £58.50 Open Toes-Sat 10.30-1.30, 230-6.30 (Ansafone out of hours) TA M Jr. Rotary dipole, 10, 15 and 20 metres .. £36.00 FARNCOMBE ST, FARNCOMBE. ELAN 3 Elements, 10 and 15 metres £69.50 ASHLEY DUKES GODALMING (Tel 23279) SURREY TD-2 Trap Dipole 40 and 80 metres £32.50 TCD-2 Trap Dipole 40 and 80 metres com- pressed . £39.50 V4 Jr. Trap Vertical 10, 15 and 20 metres .. £26.50 RACAL RA17 CO M MUNICATION RECEIVERS IS" Rack Mounting 05 to Atlas Trap Vertical 10, 15, 20 and 40 metres £48.00 30 mC/S in 30 Bands t MC,S wide. Eflective Scale Length 14511.6" corresponds to 100 KCiS Power 100-125 or 200-250 S WL ANTENNAS VAC Crystal Filter, IF Bandwidths 100C G to 8KC/S in SI. Switched Stages. S WL-7 Dipole 11, 13, 18, 19, 25, 31 and 49 BFO and Crystal Cal. A tow o123 Valves 807 and BORA used. Internal Speaker, metres . £25.00 Air Tested in good used condition with Mains Lead. Book wills Circuit. £225 Carriage Approx. £10.03. Now In Metal Case, Louvred. RD-5 Dipole 10, 15, 20, 40 and 80 metres .. £25.00 Orbit Vertical 11, 13, 16, 19, 25, 31 and 49 RAII7E Frequenc, Range 1-30MC S. Bandwidth 100C.'S to 13KC,S. In 6 bands. metres .. £43.00 Includes S Meter, has additional IF Stage (1MCIS and 1.7MC;S) Slow motion Prices correct at time of going Io press. B.F.O. usinp 27 valves BG7 and 809, rest as RA17. Price in Metal Louvred Case, as new condition with Handbook and Circuit. £300. Carriage Appro.. £10.00.

MOSLEY 196 Norwich Road, All our sets are bought direct from the government. ELECTRONICS New Costessey, LIMITED Norwich. NR5 OEX JOHNS RADIO AdnsIntatrathi• Add,.., only ENGLAND 424 Bradford Rd, Batley, Yorks (All antennas available ex works carriage and VAT extra) Phone Batley 478159 or Leeds 496048

RADIO COM MUNICATION September 1977 721 REG. WARD & CO. LTD. K.W. YAESU 103 VS WR Meter and FT101E Transceiver £429.00 combined Power Meter .. £16.00 FT2008 Transceiver and 107 Combined 8•Z March, FP200 PSU . • £289.00 VS WR and RF Power Yaesu 3010 all solid stale Indicator. Dum my Load tow £599.00 and Antenna Switch lor FR101 S Receiver £269.00 3 outlets .. • ces.ao FR101 D Receiver £390.00 K W Dummy Load. son (en- incorporating cased with 50230) • • £16.00 FT4018 £I65.00 A mateur Radio Bulk Buying Group Trap Dipole Co-axial FT224 VHF(FM 2rn Mobile Feeder £26.00 Transceiver £1443.00 RTTY TER MIN AL UNIT Tree Oleole with Balan £29.00 Y0100 Monito rscope £1113.00 3-way Antenna Switches £259.00 (tot co.as) £7.50 New G/C Receiver FRG.7 £144.00 SHURE MICROPHONES Technical Associates Audio Model 444 £10.21) Model 201 £9.50 Compressors £21.00 AII u&pve prices plJt VAT al f2¡%.

USED EQUIP MENT FR101S FB condo. £250.00. K W201 Re and handbook, complete, with external HeathlUt "Q" niultlpiler, £130.00. FT.200B/FP.200 TCVR: used low hours only on receive only £310.00. AGENTS FOR G2DY M ANTENNAS

Valves tor Yaesu. etc., 613Z6, GU8, 661:76, 12AX7A, 12BY7A. 12AUT, OvISOC, 614 0, Eurocat model ST5B 61-1F5. 01.06, 6EA8, 6066. 61468.6606. RCA Valves lor KW equipment. etc. Sentinel 2m Preamps and 2m convertors/Europa transverters, J Beams and Stolle * Tuning indicator arrangement using LEDs to aid receiver rotators. 140' 14g ant. wire, insulators, 52 6, 75 ohm co-ay. and UHF plugs, sockets tuning. and reducers. G-WhIp mobilo antenna, WIghtraps, Most couplers. Hy-Gain * Built-in AFSK oscillator for use with AM, FM, or SSB verticals. SWR 10 (Twinmeter). SWR/P WR Meters. transmitter. A MTRON KITS * Input gain control and level indicator to give correct TRADE INS WITH PLEASURE. OUR STOCK OF GOOD SECOND-HAND operating conditions. EQUIPMENT CHANGES DAILY-LET US KNO W YOUR REQUIREMENTS. * Front panel controls for Duo to currency fluctuatIone price el Imported equipment are liable to alteration. ADD 121% VAT to all prices except used equipment. 170Hz 425Hz shift HP TER MS AVAILABLE CARRIAGE EXTRA ON ALL ITEMS NormatReverse shift Normal 'Reverse AFS K ACCESS/BARCLAYCARD Receiver Transmit AXMINSTER, DEVON EX13 5DP Telephone 33163 * Housed in attractive metal cabinet 11i." 3Y B. * Built-in mains P.S.U. for electronic circuits and teleprinter magnet. * Ready assembled, tested and guaranteed for 12 months. * Price only £70.00 VAT (£8.75). , R.T. eib I. offer the finest selection of caer. (£1.25). * Version without AFSK oscillator £60.00 VAT (£7.50) first-class new and fully overhauled and carr. (£1.25). G3PLX RTTY VIDEO DISPLAY UNIT ; second-hand communications and Set of printed circuit boards: £14.85. Veroboards also available at £4.30 each. Set of i.c.s including program med 74188s, £56.15; 2513. electronics equipment in the U.K. £8.50; AY5-1013, £6.25; 2102-1, £2.85; 5N74188. £4.00 each or ready e Constantly changing stocks of a raft range of equipment. programmed £9.50 per pair. Post: add 20p. Ie Cash or Hire Purchase term. easily arranged. • Part exchanges welco med. KEYBOARD KIT • We are 'spot cash' buyers for aimait all electronic equipment. Catronics Ltd are proud to announce the introduction of the world's Send S.A.E tor our latest list o, over 50 receivers and many other inter- first modular Keyboard Kit available to the home constructor. Sating Item., The printed circuit board is designed to take a maximum of 54 keys but clay be assembled with a smaller number of keys for a R.T. & I. ELECTRONICS LTD. simpler keyboard. Ashville Old Hall, Ashville Road, London Ell Tat: 01-539 4986 The board is not dedicated to any specific coding, allowing it to Am>_ be used for any project whether it requires ASCII, Baudot or any other code. This makes it suitable for many projects including: E.T.I.-System 68 MPU (54 keys). RariCom -G3PLX RTTY VDU (36 keys) Auto morse sender, etc. The Keyswitches themselves are single pole push-to-make type BRICOM and require no extra mechanical mounting arrangements. A legend sheet is provided with each kit enabling the constructor SOLID STATE BROADBAND AMPLIFIER to label the keys to suit individual requirements. Prices: Kit for 35 station Keyboard: £31.25 Nominal output 200 Watts RMS £35.55 £39.85 Selective L.P.F. for maximum harmonic suppression £44.15 Frequency range 3-30MHz. Full V.S.W.R. protection. Please add 50p for postage. Receive Pre-A mplifier gain 10dB nominal CATRONICS LTD R.F. Switching, just TWO connections. AE and Driver C O M M U NIC A TIO N S HO U SE (Dept. 707) PRICE £235.00 20 W ALLIN G T O N SQU A RE W ALLIN G T O N, SU R RE Y, SM6 8RG 25 Byd mill Gardens, Hieworth, Swindon, Wilts. SN6 7BS Telephone: 01-669 6700

722 RADIO COM MUNICATION September 1977 D1ODES/ZE NE RS SOCKETS/BRIDGES TRANSISTORS, LEDS, etc. 1 N9I4 100v 10mA .05 8-pin pcb .25 ww .45 2N2222 NPN .15 1N4004 400v IA .08 14-pin pcb .25 ww .40 2N2907 PNP .15 1N4005 600v 1A .08 16-pin pcb .25 ww .40 2N3740 PNP IA 60v .25 1N4007 1000v IA .15 I8.pin pcb .25 ww .75 2N3906 PNP .10 1N4148 75e 10mA .03 22-pin pcb .45 ww 1.25 2N3054 NPN .35 1N753A 6.2v z .25 24-pin pcb .35 ww 1.25 2N3055 NPN 15A 60v .50 1N758A 10v z .25 28-pin pcb .35 ww 1.45 TIPI 25 PNP Darlington .35 1N759A 12v z .25 40-pin pcb .50 ww 1.95 LED Green, Red, Clear .15 1N4733 5.Iv z .25 0.1.747 7 seg 5/8" high corn-anode 1.95 Molex pins .01 To-3 Sockets .25 1N5243 13v z .25 XA N72 7 seg corn-anode 1.50 1N52448 14v z .25 2 Amp Bridge 100-pry 1.20 FND 359 Red 7 seg corn-cathode 1.25 1N524 513 15v z .25 25 Amp Bridge 200-pry 1.95

C MOS - T T L - 4000 .15 7400 .15 7473 .25 74176 1.25 74H72 .55 745133 .45 4001 .20 7401 .15 7474 .35 74180 .85 74H101 .75 745140 .75 4002 .20 7402 .20 7475 .35 74181 2.75 74H103 .75 745151 .35 4004 3.95 7403 .20 7476 .30 74182 .95 74H106 .95 745153 .35 4006 1.20 7404 .15 7480 .55 74190 1.75 745157 .80 4007 .35 7405 .25 7481 .75 74191 1.35 745158 .35 4008 1.20 7406 .35 7483 .95 74192 1.65 74100 .35 745194 1.05 4009 .30 7407 .55 7485 .95 74193 .85 74102 .35 745257( 81231 .25 4010 .45 7408 .25 7486 .30 74194 1.25 74103 .30 4011 .20 7409 .15 7489 1.35 74195 .95 74104 .35 4012 .20 7410 .10 7490 .55 74196 1.25 74110 .35 741500 .45 4013 .40 7411 .25 7491 .95 74197 1.25 74120 .35 741501 .45 4014 1.10 7412 .30 7492 .95 74198 2.35 74130 .45 741502 .45 4015 .95 7413 .45 7493 .40 74221 1.00 74L47 1.95 741_504 .45 4016 .35 7414 1.10 7494 1.25 74367 .85 74151 .45 741505 .55 4017 1.10 7416 .25 7495 .60 74155 .65 741508 .45 4018 1.10 7417 .40 7496 .80 74172 .45 741509 .45 4019 .70 7420 .15 7510BA .35 74 173 .40 741510 .45 4020 .85 7426 .30 75110 .35 74174 .45 741511 .45 4021 1.35 7427 .45 74100 1.85 75491 .50 74175 .55 74 LS20 .40 4022 .95 7430 .15 74107 .35 75492 .50 74 L93 .55 741521 .25 4023 .25 7432 .30 74121 .35 241123 .55 741522 .25 4024 .75 7437 .35 74122 .55 741532 .40 4025 .35 7438 .35 74123 .55 74H00 .25 741_537 .40 4026 1.95 7440 .25 74125 .45 74H01 .25 74500 .55 741540 .55 4027 .50 7441 1.15 74126 .35 74H04 .25 74502 .55 74LS42 1.75 4028 .95 7442 .55 74132 1.35 74H05 .25 74503 .40 74 LS51 .65 4030 .35 7443 .85 74141 1.00 74H08 .35 74504 .35 741574 .75 4033 1.95 7444 .45 74150 1.00 74H10 .35 74505 .35 741586 .75 4034 2.45 7445 .80 74151 35 74HI 1 .25 74508 .35 741590 1.30 4035 1.25 7446 .95 74153 .95 74H15 .30 74510 .35 741593 1.00 4040 1.35 7447 .95 74154 1.05 74H20 .30 74511 .35 7415107 .95 4041 .69 7448 .95 74156 1.15 74H21 .25 74S20 .35 741_5123 1.00 4042 .95 7450 .25 74157 .65 74H22 .40 74 540 .25 7415151 .75 4043 1.25 7451 .25 74161 .85 74H30 .25 74550 .25 7415153 1.20 4044 .95 7453 .20 74163 .95 74H40 .25 14S51 .45 7415157 .85 4046 1.50 7454 .25 74164 .60 74H50 .25 74564 .25 7415164 1.90 4049 .80 7460 .40 74165 1.50 74H51 .25 74574 .40 7415367 .85 4050 .60 7470 .45 74166 1.35 74H52 .15 745112 .90 74 15368 .70 4066 1.35 7472 .45 74175 .80 74H53J .25 745114 1.30 4069 .40 74H55 .25 4071 .35 4082 45

9000 SERIES LINEARS, REGULATORS, etc. 9301 .85 8266 .35 LM320K5 (7905) 1.65 LM340T-24 .95 LM723 .50 9309 .35 8836 .95 LM320K12 1.65 LM340K-12 2.15 LM725 1.75 9322 .85 MCT2 .95 LM320T12 1.25 LM340K-15 1.25 1M739 1.50 95H03 .55 8038 3.95 L10320115 1.65 LM340K-18 1.25 1114741 9-14 .20 9601 .75 LM201 , .75 LM 339 .95 LM340K-24 .95 1M147 1.10 9602 .50 LM301 .25 7805 1340T-51 .95 LM373 2.95 LM 1307 1.25 LM308 Mn)' .75 LM340T-12 1.00 LM380 .95 1M1458 .95 LM 309H .65 LN1340T-15 1,00 LM70918.14 PIN) .25 LM3900 .50 MEMORY CLOCKS LM309Ki340K-81.85 1M3401-18 1.00 LM711 .45 LM 75451 .65 745188 (82231 3.00 LM310 1.15 NE555 .50 1702A 7.95 LM311Dimina .75 NE556 .95 MM5314 3.00 LM318 s.iiiio .65 NE565 .95 MM5316 3.50 2102-1 1.75 INTEGRATED CIRCUITS UNLIMITED NE566NE567 1.351.75 21021-1 1.95 SN72720 1.35 TMS6011NC 6.95 7889 Clairemont Mesa Blvd. San Diego, CA 92111 U.S.A. SN 72820 1.35 8080AD 15.00 No Minimum 8713 1.50 All prices in U.S. dollars please add postage to cover method of shipping. Oiders 8723 1,50 Over $IDO (U.S.) will be shipped at no charge. Payment should be submmed 8124 2.00 with order in U.S. dollars. Orders shipped same day as received. 2)0713-4 4.85 24 Hour Phone (714) 2784394 MesterCharge / liankAmericard

RADIO COM MUNICATION September 1977 723 Can YOUR Antenna QM 70 ELECT R011, ICS hi It L it do all this? LET US You've read our ads with their recent testimonials and user histories-so this month we thought we'd remind readers of the selling points of the CONVERT YOU JOYSTICK VFA (World Patents) Q M70 ELECTR ONICS now offer you the most comprehensive * Only 7' 6' long, comes in 3 easily assembled sections. range of Amateur VHF and UHF Converters available today. * Tunes 0.5.30MHx. no gaps NE WLY INTRODUCED are our Dual Band Converters * Matching Antenna Tuner. which are designed for the operator who wishes to listen to the * No harmonic resonances- moans that the highest efficiency transfer of 432434 and 434.436 MHz bands. power and waveform from TX to ether takes place. In turn this ensures that TVI and other spurious emissions are just not •ubstantially present. OUR RANGE OF CON VERTERS now include all those * Low angle radiation as an effective ground plane-that husbanded below. power goes on to reach destination with the least number of loss-making skips. For 4 Metres 70'28 £19.00. * Gives receiver additional front end selectivity and gain-reduces cross. For 2 Metres 144,28 £19.00. mod and out of band blocking. For 70cm 43228 £27.00. * Your installation can be "tailored" to space available. Install VFA on mast or chimney or in roof space with a long or short feeder-or SIMPLY 432-434128 £31.50. STAN O IN THE SHACK. One delighted user proved his VFA by opera- 4321144 £27.00. ting FROM A BASEMEN T! 432-434/144 £31.50. ALREADY IN USE BY AMATEUR TRANSMITTING AND SWL STATIONS W ORLD-WIDE AND IN GOVERN MENT COMMUNICATION. Available with either Belling Lee or SNC sockets. Please state which are required at the time of ordering. All IF's 28-30 250w. p.o.e. OR for MHz or 144-146MHz as indicated. SYSTEM 'A' the SWL £36.00 See our previous adverts for details of our other products. Agents: Peter Avill G3TPX, Dorton 2517. Gordon Adarns G3LEC1. Knutsford 4040. (Both OTHR). 500w. pep. Amateur Electronics. Amateur Radio Exchange. Craylord Electronics. D P (improved 'IX Hobbs. Leo Electronics. Waters 6 Stanton. SYSTEM `J' on receive) £42.60 All prices Include VAT and UK Mainland carriage. All units gueranteed tor 12 months. Large SAE for lolly descriptive literature.

Q M70 ELECTRONICS LIMITED PARTRIDGE SUPER PACKAGES Severnside South. Bewdley, Worcestershire DY12 2DX. Manu facturers and suppliers of VHF equipment lo the Amateur and Professional user. CO MPLETE RADIO STATIONS FOR ANY LOC ATION

All Packages feature the World Record Joystick Aerial (System 'Al, with 81t. % let feeder, all necessary cables, matching communication headphones. Dellv. Securicor our risk. ASSEMBLED IN SECONDSI BIG CASH SAVINGS! PACKAGE No. I. As above with R.300 RX. SAVE £17.261 £210.55 G. W. M. RADIO LTD.

PACKAGE No. 2. ALL PRICES Include VAT and Post!packing

Is offered With the ERG? RX. SAVE £12.21 , £193.11 RADIO TELEPHONES

PACKAGE No. 3. 100kc s CRYS TALS in 12v oven. Er Racal units, £2. DPCO JENNINGS Vacuum relays, 48v colt, new, £5. New low priced package, featuring the all.solid GRASSLIN Elapsed woe meters, 2" square, 240v 50cyc.100,000 hours max. by tenths. state SMC 73 Rs., with all the Partridge extras. New. £2.50. SAVE £17.28! £154.86 Admiralty Pattern 160100 PARALLEL ROLLING RULES. Solid brass, f.13 or pal- ished £11. Complete in wood box. RECEIVERS ONLY, inclusive deliv etc. G.E.C. Air Traffic Control Transmitters, 10 watts A.M. around 121 Mc¡s. AC moms, £10. R.300 £184.50 FRG7 £162.00 SMC 73 £128.81 VITAVOX CN224 Table Microphone stands, new and boxed and professional quality. £6. Just telephone your card number- AIRLITE model 62 head and boom mike sets, £5.50. CA MBRIDGE Lo Band FM or AM complete cable, box, mike and speaker, £35. phone 0843 62535 (or VANGUARD units only single channel valve Lo band, no accessories, £11. 11111111 M 62839 after office hours) ISOLATION TRANSFOR MERS. Double wound 0-250In, 0-115-250 out or vice BARCLMCARD 1 versa.250watts. 5' • 45' 3. weight 12 lbs, shrouded type, £4.50. W ATTMETERS, or write for details, send Absorption AF No. 1 (CT44) 200 microwatts to 8 watts at 2.5 ohms to 20,000 ohms, £12. I. BC.201 FREQUENCY METERS. Complete with charts, less power supply. These 9p stamp are recently recalibrated. £20. INTRUDER ALAR MS. Photo electric. Tx1Rx and control unit. Put a lIght beam over NOTE: All truces are those current at time of closing for press, inclusive of garage drive to open doors? Max span 10It. £10. 1217..‘ VAT and carriage. RECEIVERS B40. Two only £50 each. One only Marconi Atalanta, £150. OSCILLOSCOPES CT436 double beam. good workers, £75. G3 CE D G3VFA METERS. 500Y De. modern plastic type, £2.50 new and boxed. B44 Mk 3. 60 to 75 Mel's Hal controlled AM, no battery lead or mike, £10. Last of the many. Mikes ex-Naval outdoor Ilse. Large rubber mouthpiece cancels out Wind noise. Moving coil 20;30 ohm. t.e. TRANSFORMERS. 0.250 In, outputs, 5v 6a, 70v 2a, 5v 3e. 450.0-450v 310rna, 6.3e So, 6.3v 3.5a, 350-0-350v 3700m. 6.3v in. new, oil filled and potted, PPTRIDG 6 weight 30Ibs. 6' 61" 61'. £5. gMagr:: "7/,g5 .f:-/YCL ;i/Vi« Carriage charges are for England and Wales only. za-TAVINIC Ternis: Cash with order Early closing Wednesday Box 6, Partridge House, Prospect Rd., Broadstairs, CTIO I LD G. W. M. RADIO LTD. 40.42 PORTLAN D ROA D, W OR THING, SUSSEX Telephone 34887 (Call ers by appointment)

724 RADIO COMMUNICATION September 1977 N.B. 2 ALEXANDER DRIVE, HES WALL, P . M . ELE C T R O NIC NEW WIRRAL, MERSEYSIDE, L61 6XT Tel: 051-342 4443 (4.30-7.00Pni) SE RVIC E ADDRESS Cables: CRYSTAL, BIRKENHEAD. Toles: 627371 VAT -PRICES EXCLUDE VAT, W HICH SHOULD BE ADDED AT THE HIGHER RATE (125%) FOR ITEMS MARKED (H) AND AT THE LO WER RATE (8) FOR ITEMS MARKED (L)-OVERSEAS ORDERS (Inc. Eire and Channel lees) NO VAT CHARGEABLE. 2M TX & RX CRYSTAL AVAILABILITY & PRICE CHART CRYSTALS FOR THE NE W BRITIS H 70C M CHANNELS Wo aro stocking the following channel, RIZIO (43460)432 00). 082 (434 65/43.3 05). RB4 CRYST AL D D (434 -70/433.10), RB6 (434-75)433-15h SU8 (433-20), R810 (43485)433.25), RB14 (434-85,/ FREQUENCY 433 .30, SU18(433.45) and SU20(433.50)-TX and RX for use with: PYE UHF Westmin- RANGE z D D ii D 7 ster (VV15U), UHF Cambridge (U10B), PockotIono (PEI) and STORNO COLICQM 662 USE (TX or RX) allot £2.36 plus VAT (H). For the U450L Base Station we have iha TX cryStals tor all the end HOLDER abovechannels plus the RX crystals for SUS and R814 also at £2,36 plue VAT (H). The ).‹ ,•., )lc ›lc x ic X IC RX crystals for REQ. 084, 086. OBIS. SUIS and SU20 for uso In the U4501 Bane Station, w 1- ›- cc tc t- w I- . . together with the TX end RX crystals for tire remaining SU channels (SU12-433-30. I I I I I I 2 I RTTY. SU16-433.40 and SU22.433-55) for all the above equipments are available at OUTPU T 2 2 2 .2... £2.90 plus VAT (H) delivery as per class (h) 2w items. FREQUENCY .1.t...g. - z e . 4rn CRYSTALS FOR 70.26MHz-HC6iU 44.030 b b b TX 8.7825MHz and RX 29•7800MHz . . at £2.36 each + VAT (H) 44.41433-2 .. c b b RX (•7466MHz . . at £2.90 each + VAT (H) 44.480 .. b e b 10•245MHz "ALTERNATIVE" I.F. CRYSTALS -E236 + VAT (H). For uso In 44.800 .. b b b PYE and other equipments with 10-7MHz and 455kHz IF., to get rid el the "hirdy" lust 44-850 b b b acre.> cr I 4MHz•TX-HC6/U 4MHz•TX-HC6/U I cr acre.> 45.000/SO .. a shove 145 .0MHz. In HC6/1...1. HC18/IU and HC25,U.

45.0501R2T .. b CRYSTAL SOCKETS -H U M, HC13 ,11 and HC2.5(1J (Low loss)16p each • VAT 45 -075IR3T .. b (H) it 10p P. 8. P. per order (P.1. P. free If ordered with crystals). o 45•1001047 .. b CONVERTER/TRANSVERTER CRYSTALS -HC18,1) 451251051 .. b All nt £3.00 + VAT (H). 38 6666MHz (144128), 42M1-le (70128), 58MHz (1441281. 70MHz 45 1501R6T .. b (144)4). 71MHz (144)2), 95MHz (342152). 96MHz (1.290;432 144), 101MHz (432(28). 45.175/R7T .. b 101.50MHz (43428), 105.6666MHz (1,295,28) end 116MH: (144128). 45.200/R8T .. a - cr cr cr cr I 6MFIr-TX-HC251U 45 3001512 6MFIr-TX-HC251U .. I cr crcr cr b CRYSTALS SPECIALLY MANUFACTURED FOR AMATEUR USE 45.3501S14 .. b TO CUSTO MERS REQUIREMENTS cr cr cr cr cr cr a a a a o a a o cr IIMHz-RX-HC6/U IIMHz-RX-HC6/U cr o a a o r• a a a >on, a cr cr cr cr cr cr cr cr cr cr mmmmmmmm cr cr crn cr 12MHz-TX-HC25/U 45 12MHz-TX-HC25/U .4601S16 cr .. crn cr cr mmmmmmmm cr b Now supplied to our new Improved amateur specification tot. ±30P0m 0-60 C.

45 .5001S21 .. adl.tol. ±30porn) as follows: In HCOU 1-5.2MHz £3.95 + VAT (H) end HC61112-105MHz 45 -5251S21 .. and FICISIU and HC25/Li 4-105MHz £3.00 VAT (H) Delivery usually 4-6 weeks. 45-5501522 .. Please givo circuit conditions (I.e. load In pl Mc.) when ordering. Fundamentals 45 -5751523 .. (1-6.2IMHz) will be supplied to 30pf conditions, and overtones (21-105MHz) to

45.603/5248MH,TX-HC61Ij cri .. cr a cr cartes resonant conditions unbent otherwise specified. For details of closer tolerance . . . SIIDODD SIIDODD 45-650/020 .. 0 crystals please send S.A.E. . ,

45.615103R .. 0

. TEST EQUIP MENT FREQUENCY STANDARD CRYSTALS - 45 .700/R4R .. 100kHz in FIC13/U, £2.95 + VAT (L) 45-725105R .. 7DID b

, 1Mv AHTz(La)nd 5MHz in HC6IU and 10MHz and 10.7MHz in HC6IU and HC251U. £2.80 -

45.750jR6R .. 000 0 b . . 45.7751R7R .. b

uwee mmmmmmmm a a cr cr cr a a cr cr a • cr cr cr cr 11)MHz-RX-HC6/U 11)MHz-RX-HC6/U cr cr cr cr • a cr cr a a cr cr 45.800/R8Rcr a a .. mmmmmmmm uwee 0 0 a BURNS ELECTRONICS . cracrucre.o 45 -05 .. 000 o 0 oomvecrurr b We are tho Northern Appointed Agents for BURNS KITS etc, ano can supply most 1 l of their products front stock. PRICES: (a) £2.36. (b) and (c) £2.90 -i- VAT (H). AVAILABILITY (a) and (c) stock Hems, normally available by return (we have M ODULAR CO M MUNICATIONS SYSTEMS over 4,(k70 Morns in stock). (b) Four weeks normally but It is quite possible we could For Ihe RTTY enthusiast we can recommend and supply the "IVICS" range cit Prod- be able lo supply Inam stock. N.B. Frequencies as listed above but In alternatIve ucts. This Includes terminal units. AFS keyors, magnet drivers for TTL Interface, holders andlor non-clock loads are available as por code (b). telegraph distortion measuring adaptor, RTTY audio processor, power units, etc. etc. ORDERING. All we require to know is (I) Output frequency, (2) Crystal frequency For the CW man we have the "MCS" CW filter which gives three stereos of aclIce range. (3) The holder, and (4) Either the load capacitance (pfs) or equipment.11 Is not filtering. Please send S.A.E. for full detail, of tho "MCS" range. eartential to glee the exact frequency. though it would be of assistance In quote It 11 ANZAC MD-108 DOUBLE BALANCED MIXER known. 5-5()OMHz supplied with full details for only £5.95 plus VAT (L). JAPANESE AND AMERICAN EQUIPMENTS With the over Increasing populerity ci Japanese equipments we have further expanded our range ol stock crystals. We can now supply for YAESU(FT2F.FT2FT. FT2 Auto. CRYST ALS FOR PROFESSIO N AL USE F7224), moat of the ICO M rangn and the TRIO-KEN WOOD range. We can also /nerdy from stock crystals for the HEATHKIT H W202 and HW17A. CRYSTALS TO CO M MERCIAL SPECIFICATIONS We can supply crystals to most commercial and MIL specifications, with an exprase YAESU FT221 CRYSTALS NO W IN STOCK. ALL AT £.90 VAT (H). All popular channels-Fur repeater use advice slat frequency required as earlier models have service for that urgent order. Please send S.A.E, for detalle or telephone between difierent shift stale to later FT221R. We can oleo aupply the crystal to Wye NORMAL 4.30-7pm and 88k lar Mr. NorcliCo. "tune to RX" worldng (as FT221R) For 70 cm we can supply the 1-6 MHz shift ata) for direct use with n MICRO WAVE MODULES MMT4321144 which we can supply for TER MS: CASH WITH ORDER - MAIL ORDER ONLY -S.A.E, WITH ALL £133.00 VAT (H). SPECIAL OFFER I If ordered with gansvorter 70cm shift crystal ENQUIRIES -PRICES INCLUDE P. 8. P. (BRITISH ISLES) EXCEPT WHERE FREEI I STATED -OVERSEAS CHARGED AT COST.

CRAYFORD ELECTRONICS SUM MER SALE G MT N 661WX ANTEC HELICAL FLEXIBLE AERIALS 10% OFF ALL PRICES FOR CASH & NO PART We can supply a wide range for frequencies Iron: 68.503 MHz. They are con- EXCHANGE structed using a tapered copper-plated steel hells, and covered In a neoprene TRIO JR599 CUSTOM SPECIAL, 160.2m. Mint .. £170.00 material. giving strength and flexibility. All are currently ex.stock. YAESU FT-224. 2m Transceiver, 8 channels 150.00 For 145 MHz :- LINER 2 as new . . . .. • • 130.00 FX2200GX For Trio 2200GX £2.25 TRIO 7200, 10 channels .. 130.00 FXUHF With PL259 plug Y RIO 2200, 7 channels, all accessories .. 110.00 FXBNC For modified 2200. 2200G, KP202, etc. YAESU FR•5013, 160-10m, all stale + cal. .. 90.00 FX nrinTNC For Pye PF70, otc. £4.22 A RAC 102, 3e: end 10m receiver.. •• 80.00 F8560 For Storno 500 series 65.00 For 433 MHz:- OSKER SWR•200 . 22.00 FXUBNC With EINC Plug . • ••• ••• ••• £2.76 BELCO M 12V DC PSU .. •• • • 16.00 EXUntInTNC For Pye PF70 UHF series " W2AU" Batons AMIDON TOROIDAL CORES. SAE for details. EXU4 WIth 48A threeid-mod/flod PEI £2.13 Others available, a,‘ unit coming soon for 3200GX TMP ELECTRONIC SUPPLIES SAE Enquiries and lists Post 20p VAT EXTRA 124% 3 Bryn Clyd, Leeswood, Mold, Clwyd. CH7 4RU. 6 LOVELACE CLOSE, W EST KINGSD O WN. SEVENOAKS. KENT, Tel: Pontybodkin 848 (035 287) TRIS 6DJ 24 Hr. Answer Service 047485 2577

RADIO COMMUNICATION September 1977 725 CONSTRUCTIVE INNOVATION Each of the products below pioneered new techniques and new performance standards. Sometimes the benefits are obvious, sometimes they are subtle. We like to think that Datong customers appreciate both kinds. FRE QUE N CY-AGILE AU DIO FILTER R.F. SPEEC H CLIPPER M O DEL FL1 M O DEL RFC Processes speech as a SSB A versatile bandpass or band- signal at 60kHz to increase reject filter with fully variable its ratio ot average to peak bandwidth and centre frequency levels without adding har- plus unique search(lockitrack monic distortion. Improves capability for automatic removal talk power of SSE1. FM, and of heterodyne whistles. Improves AM transmitters without in- reception ol C W. RTTY. and creasing the peak trans- SSB. Connects between receiver mitted power. Connects and loudspeaker. between microphone and Adds fulirecelvIng coverage horn transmitter. (See articles by UP-C O NVERTER MO DEL UC/1 90kHz to 30MHz to existing re- Dr. D. A. Tong. Wireless ceivers or transceivers tuning 28- World Feb. 1975. 79-82 and 29MHz or 144-145MHz. The full Oct. 1976, 77-81). range la coverodin thirty 1MHz wide synthesiser controlled segments. Also works as a two- metre converter. Con- nects between receiver and antenna. Also available with alternative Input connectors and as The descriptions above are brief. Please send tor free coptes of our data sheets and read the full story. printed circuit module Geis Please note that the following revised prices will maul/ from August 22nd; UCa. £105.00; ELI. £52.00: (MODEL RFC/M). RFC/M. E.21 .50 ; RFC. MO M (with either Jan. 4-pin or sleeve lack input connector). All plus VAT at 121%. Prices include delivery within UK. A range of accessory leads is also available, full price list on request. D AT O N G ELE CT R O NIC LIMITE D DSpence Mills, Mill Lane, Bromley, Leeds LS13 3HE. Tel: Pudsey (0532) 552461.

THE TU8 AUTOM ATIC TELEPRINTER TERMINAL

The latest in the family of RTTY Terminals from Churchtown Electronics brings you professional performance for the discerning Amateur.

Become_ Featuring • Automatic Motor Control a radio You can now receive signals in your absence. • Electronically Protected Receiver Power supply for safe continuous operation. • Receives and transmits 170-400-850Hz shifts using latest IARU approved amateur. frequencies. Learn how to beco me a radio- • C. W. Identification. amateur in contact with the whole • As with our previous models you have both L. E. D. & outputs for 'scope world. We give skilled preparation tuning. for the G.P.O. licence. • Single switch operation when using a vox transceiver gives you that fast break In. • High stability AFSK oscillator using Integrated circuits for low distortion. Br ochuqe, milker, oblielion to. RCK97 • Fully self contained unit approx 12' w 5' h 8 deep. BRITISH NATIONAL RADIO Outputs cart be simply interlaced to drive most visual displays or FSK generate rs. & ELECTRONICS SCHOOL

The low cost, high quality automatic for £218.00 + VAT. Total £245.25. Ea 15C. JerzeY i Channel Islands- stock from NAME CHURCHTO W N ELECTRONICS ADDRESS Saint Merryn, Cornwall PL28 8ND (0841) 520535 (Mock cope picateli

726 RADIO COMMUNICATION September 1977 NOTE NE W Shop Hours 9.30am to 5.30pm Mon. to Sat. Easy access to the MS, MEd, M62, M63 STEPHENS-JA MES LTD PHONE NU MBER 47 W ARRINGTON ROAD, LEIGH, LANCS W N7 3EA TEL 0942 678790 NO PARKING PROBLEMS SWL Tuning Unit Mk 1 2-30MHz .. £17.50 YAESU MUSEN 2m 8 Element .. £9.11 SWL Tuning Unit Mk 11550kcs-30MHz £25.00 FTIOIE Transceiver 2m 10 Element £19.35 NY-KING Morse keys .. £8.75 FT2006 Transceiver PBM1412 Parabeam . £28.35 KATSUMI BRIS electronic koyer £50.72 FT40113 Transceiver .. 2m 5 over S .. £12.37 FT221 Transceiver .. 2m 8 over 8 .. £16.59 S.T.E. MILAN FRIO'S Receiver .. 2m Ground Plane .. £6.42 ARAC 102 2 band Receiver.. .. £100 00 FRIO'S Digital Receiver 2m Crossed DIptee £9.124 Atal 222 144-146MHz AM-FM TX £126.00 FRIOID Receiver .. SPM Portable Mast .. £9.50 ARIO 28-30MHz Receiver Module £77.50 FRIOID Digiloi Receiver 8 Element Crossed 2m £18.11 AT 144-148 Transmitter Module £50.00 FL2I00 Linear Amplifier 6 Element Crossed 2m £14.51 AD4 FM Discriminator .. £5.00 TO-100 MonilonleOpo 2m 4 Element Quad .. £14.85 AA1 Audit) Module .. • . £4.25 YD844 Desk Microphone 2m 6 Element Quad .. £19.80 AGIO Tone Generator .. £4.50 10866 Hand Microphone DiV70cms £14.06 AT23 10 Channel Crystal Tx Module £45.00 FRG7 Receiver.. .. P8M/18.70cma £16.85 AT20 10 Channel Crystal Ra Module £50.00 MBM48/70cms Multlbeam DRAKE £19.85 AL8lJnear Amplifier Modulo £7.00 R4C Receiver .. £450.00 MBM88170cms Mullibeam £26.32 AS15 stabilised 12V de board £9.00 1410 Transmitter £450.00 AK20 2M FM Transceiver £170.00 TR4C Transceiver £475.00 MICRO WAVE MODULES AK20 FM Transceiver Kit £110.0e MMC144 2nt Converter .. AC4 AC Poe . £90.20 £20.25 Burr 20 Electronic kern' . £106.00 MMC,144 LO .. MS4 Speaker .. £21.02 £22.50 MMC70 SSR-1 Receiver £185.00 £20.25 TECHNICAL ASSOCIATES MM C/70 LO .. £22.50 SPR-4 Receiver £510.00 Audio Compressor -- £23.62 MMC432 Low Pass Filter £18.00 £24.70 Notch Filter £25.60 MMCI 290 .. £28.12 Bend Pass Filter .. £25.60 DECCA COMMUNICATIONS MMA144 Pre-amp £14.62 Crystal Calibrator . £21.37 KW204 Transmitter .. £241.25 MMV1269 £33.75 Preseloctor £25.70 KW107 Antenna Match £95.63 MMT432128 £109.12 KW 109 Antenna Match £118.12 MM0050 £69.75 SECONDHAND EQUIPMENT KW Antenna Switch £9.00 £28.12 Liner 2 Transceiver £135.00 KW Batan £9.56 MMD 05015000 Frequency Counter £88.87 Eddystone EB35 Rociase' £70.00 KW1000 Linear £281.25 MMT 432/144 £149.62 Grundig Sat null Receiver £90.00 KW202 Receiver £236.50 MMT 144/28 £80.87 Eddystone 770U Receiver £150.00 KW Traps • • £9.56 Yaosu FT221 VHF Transceiver .. £295.00 UNIDEN BELCOM Icom IC21 VHF FM Transceiver £125.00 2030 2m Fm Transceiver Liner 2 Transceiver E1911.541 £178.37 STE AK20 VHF FM Transceiver £130.00 Liner 430 Transceiver UNIDEN 2030 VHF FM Transceiver £130.00 G-WHIP MOBILE ANTENNAS NR-56 Tunable FM Receiver .. £54.00 STE 228 Transmitter and AC oau £115.00 10-15-20m Helical Whip .. £18.11 AMR 21713 Scanning FM receiver £100.87 Trio JR500 Receiver £60.00 Besemount £2.47 Belcom AMR 104 H Receiver (8 crystals £70.00 Coils for LF Bands each .. OMEGA £5.48 Heathkil IB-1100 Frequency Counter .. £55.00 7E-701 Antenna Noise Bridge 2-30MHz .. £2Loo Fieslwhip Basic with mount £15.00 Uniden 2020 Speaker .. £22.00 TE-702 Antenna Noise Bridge 2-220MHz £25.00 Colis for all bands each .. £5.60 S.T.E. Bug 14 Electronic Keyer £65.00 80-40m Traps .. ROTATORS £8.10 Trio 15510 Transceiver .. £195.00 160m Traps AR30 .. £42.19 £7.90 Yaesu FRG7 Receiver .. £135.00 ARID Yaesu FT101 Mk 2 Transceiver £325.00 CALLETTI VHF Antenna range CO44 .. £100.13 ICOM IC225 FM Transceiver £140.00 2m Ground plane. 4 radials Ham 11 £133.38 £13•10) Sony CRF-160 Receiver .. £90.00 2m Gutter mounted mobile whip £12.00 ARAC 102 Receiver .. £85.00 NV-GAIN r 2m Standard mount mobile whip £12.00 Drake SSR-1 Receiver £125.00 I2AVQ 10-15-20m Vertical .. £38.80 Taegu FR101131Recarver £355.00 14AVT 10-40m Vertical .. £53.43 ACCESSORIES 18AVT/W8 10-80m Vertical £72.61 UR43 50ohm Co-Ax per moire 18p ALL OUR PRICES INCLUDE VAT TH3MK/3 Tribander Been) £140.17 UR87 50ohm Co-Ax per meter 45p Stamped addressed envelope please with all genera; THEDXX Tribander Beam .. £163.30 300ohm twin feeder 10p enquiries. Postage extra al cost. Deliveries free In BN86 Balan £20.25 70ohm twin feeder .. lep some areas Bumper Mount.. .. £6.75 75ohm low loss co-ax 109 Single meter SWR Meters .. ATLAS £1020 ACCESS AND BARCLAYCARD FACILITIES PL259 Plugs .. Full after sales service. All equipment sir tested and 210X Transceiver £445.00 50p 50239 Sockets 459 215X Transceiver .. .. £445.00 sold from above premises. We do not employ uno Cable reducers 169 part-time sales staff or soil to private individuals for JAVBEAM ANTENNAS Line connectors 7515 resale. On the spot HP and credit facilities available. 4m 4 Element . £11.47 Junkers Heavy Duly Morse Keys .. £29.57 Part exchanges welcome. Instant cash paid for good 2m 5 element .. £6.94 Baeur Paddle Unit .. £9.87 clean equipment ter you at a email commission.

JA ME S & M A R TIN ELE C T R O NIC S LT D NE W! TONE BURST GENERATOR Staines Road, Feltha m, Middx. TBG-2 PROTOTYPE AND PRODUCTION METAL WORK * Crystal controlled for depend- Specialists to the Electronics Industry. Panels, chassis and able repeater access. sheet metal details. Milling, turning, drilling. Machining in all * Small size, fits any trans- metals and plastics. G3VVB. ceiver-22-6SL -.12.50W ). 11-80H. Tel 01-570 3127 Plant list on application. OS Ref TQ 113718 Just connect In the push-to-talk line 5-15V, +ve or --ve earth.18-way DIL package may be soldered on to a IMANI 1:0121:1EFtei PCB or simply glued into a con- Flexible PCB: or e Ir. SAE for sample. 40p nor sheet, or 20p any number. venient position. 10 Miniature HC25U and IOU Xtals, my choice for Et post 10p. Supplied with full instructions. £8.00 UR67, 50 ohm low loss Coax, approx. r dia, at 30p per m, post 1p per m. each 124% VAT, post free. 20-core screened Cable, up to Em coils at 11Ip por m, p081 59 per m. OEM enquiries invited for these and logic compatible crystal 500 Resistors, mixed Carbon Film, 1W to 1181.5 W. £2. Post 159. UR76. standard 50 ohm Ceex, stranded conductor et 10p per m, pp np per m. oscillators (IPX0). 240Hz-20MHz. SRB 240V 18W Miniature Soldering Irons. let quality, £3.50, post 40p Lois more CebleelXtels, etc on my lists SAE for your cony. INTERFACE QUARTZ DEVICES LTD W. H. WESTLAKE. CLA WTON. HOLS WORTHY, DEVON 29 Market Si., Crewkerne, Somerset. Tol (0460) 74433. Telex: 45283

RADIO COMMUNICATION September 1977 727 A M ATEUR RADIO ,isoP le% EXCHANGE e te e9 Proprietors: Brenda Aptaker, Bernard Godfrey (G4A0G) ttt The Aladdin's Cave for the enthusiast, with a secondhand selection that is second to none. Come and browse ... Come and buy ... Come and have a cup of Brenda's coffee either way.

* AUTU MN LISTENING * Not only ... the finest general-coverage synthesised communications

ByTelephone receiver on the market, now with Fine Tuning, at a basic SECURICOR price of £162.00 inc. VAT. DELIVERY 111 But also ... available from us with special e • 2m converter and accessories, all for only £179.00 inc. VAT.

EASY TER MS Phone for full details of current stocks-new and secondhand-and opening hours, UP TO 3 YEARS or see us on our Stand at the Harlow and Leicester Rallies.

2 NORTHFIELD ROAD, LON DON W13 9SY. Tel 01-579 5311

. INTEGRATED CIRCUITS W HOLESALE * .* HAM-SPARES AT BARGAIN PRICES ENQUIRIES . .* INVITED . ,.. G:ji,VCS G4C00 SN 76003N Audio amp and HT sink 4W 35e 15 R£ 50 * * SN 76033N Audio amp and HT sink 4W 35v 15R E1.50 01-743 0899 .. .. 262 KENSINGTON, TBA 641Al2 Audio Power amo. 4.5W £1.50 if, H S .y..* 170, Goldhawk Road. it- * LIVERPOOL L7 2RL. Tel. 051-264 9924 COLO MOR ELECTRONICS LTD., London, W.12. * * * * QUALITY COMPONENTS AND ACCESSORIES * * BY RETURN-AL WAYS * NE W ROBOT SSTV

Special ode, Packs al 10 Plastic BC107. Full spec., brand now. 50p. "400" Solid state slow to fast and fast to slow Scan converter with Digital Ran- 2200G X Inserts. Good audio quality, suit any rig 2C0-600 ohm. Seale output as dom Access Memory, lor full brightness. non lading, pictures of unbelievable original, no adjustment required. £1.60. definition on a normal TV set. Also picture transmission from a standard CCTV Level Meters. Small uncalibrated melero, ideal for rf out Indicator, etc, etc. camera. £666 not. VAT. S.A E. for details please. 200mA FSD. New batch just arrived. 55p. Red Led's. Miniature size with holder. Limited number. 5 for 55p. ABRO & GENERAL SUPPLIES. Nanalmo House, 32 Rufford Avenue, Brarncote, Nottino ham NG9 33H. Tel. 397588 PTT Microphones. 50K or 300--600 ohm with transformer removed. Normally sell at £5.50. Limited number lell at £4.50. Veroboard. At less than hall price. Packs of six pieces in different sizes and matrix. Our choice. Excellent value £1.00. TBA 120,'SN 76660. FM discriminator I.C. Unmarked but fully tested. 4.5p. SCANNING YET? Neon Panel Indicators. Wired with resistor for 240V. 5 for £1.10. FM1OA 6 FM2A modules as June ad. Headphones. Mono, comfortable padded earpieces. Ideal for all communications. Can be used for stereo. £3.65. C1-1A module. Converts single line Inputs to 7 segment-reads 0-9. Use as Solder at half price. Packs of multicore, reduced from 40p to 20p. channel indicator. with led. £4.85 requires F 5V. Reed relays. For recent keyer desions and other high speed switching. Operate FM-4A. Boxed scanner module. 4 channels with switches and led's. Size 6" o3' on 9V and above. Heavy duly contacts. 30p. r 2'. Ready to use with diode switched rigs. £15.95 complete. Details S.A.E. Mosfets.RCA. all full spec. 40673!40522, 65p. 3N204 very tow noise figure rnosfet. Same connections sod bias as 40673. £.Z5. A. L. BAILEY. 9 ALBERTA WALK. WORTHING, BN13 2SG.

Celina Plugs and Sockets. High quality. Low loss. PL259. no reduced required for UR43,67 cable, 67p. S0239 sockets, 4 hole type, 46p. Single hole, 51 p. EINC 50 ohm okra. 51p. BNC sockets, 4 hole type, 43p. Single hole. 44p. 'N Plug, 88p. LO SI N G D X ? PL259 back lo back coupler. 7517. Maybe your ANTENNA is FAULTY. . . Find out FAST with an ANTENNA NOISE BRIDGE. Measure radiation resistance 20-200 ohms and resonant This Is only a small selection from our large stock. Our catalogue is available tree frequencyl.150MHx. All parts, rt transformer, printed circuit, ' .•• 3' • 5' case. of charge, please write or phone for copy. Callers welcome 9arn to 5.300m, hall day Wednesday. Closed third week in September, all orders despatched battery, screws etc. instructions, postage, money back assurance. MORE DX for ONLY £8.20, send TODAY. immediately on return. Postage 25o on small items. 359 on microphones and headphones. All prices 45t ' Old School Lane. Include VAT. CAMBRIDGE KITS Milton, Cambridge.

728 RADIO COMMUNICATION September 1977 G4DS G D. P. HOBBS LTD. G3HEO GAREX (G3 Z1/1) The Co mponent Specialists BRITIS H MADE V.H.F. EQUIP MENT T WO M OBILE FOURM OBILE Companion units for 20,4 metres. They feature Tx, Ra and PSU for 12V DC Bolcom Liner 2 Mk2. 2 metre trans• M MC 1296-23cme Convertor any IF input In a single unit 12 a 8 e 4i, -. Full coverage tunable AM/FM Ra with m eet £184.50 £28.13 excellent V.F.O. stability oven under mobile conditions. ProlosslOnal grade Bolcom Liner 2 Power unit £3130 M MA 144.2 Metre Pre-Amp £14.63 sensitivity AND selectivity. Crystal controlled AM,FM Tx, with superb audio Unlden 2030 12 Channel. 2 metre M MT 432-28M Ho Transverter £110.10 quality. Based on popular Fin' components for ease of servicing and ready availability of spares. Comprehensive handbook and low-cool after-sales Transceiver fitted five channels MT 432'144MHz Transverter £149.63 £147.38 service. Prices: Twornobile £131; Fourmotalle £1121.50 (Inc. VAT). M MT 144 23MHz Transverter £88.63 We stock the popular NR56VF-1 2m Ro., w;th switched 144-145MHz V.F.O. 0 5078 28,144 Scorpion Transverter M MV 1296 ,70 23cms Varactor and 11 ztal controlled channels. ideal for fined, portable or mobile use. £100.00 triplet £33.75 Built-in LS.. 12V DC operation. £54 Inc. VAT. (alai. £2.41 each, all usual Cobra 250/70 CMS FM. Transverter channels in stock). NR56 VF1. 2 Moire Monitor receiver with Mic. Audio £36.00 An s.a.e. brings you ul I details olany ol the above. Credit facilities available £.54.00 2 Metro Solid-Slate Linear Amp. end part-exchanges welcome, FOK Multi-11, 2 metre transceiver £52.00 NE W CO MPONENTS: £189.61) 23 channel Relay GPO typo 3000, IQ coil, pull-in current epprox 200mA. 1M -1 18 2J11144 Solid-State Transverler FON Multi•U11 23 channel 70cms contacts, !dentin' psu out-out. 75p £60.00 transceiver fitted 5 repealer end 4 Integrated circuits (lull spec.) Simplex channels Auto-Scan on 2FM70 2M to 70 CMS. FM. Trans. 723 voltage reg. TOO metal case. 2137V out all50mA for 5/40V in 75p 433.5, 433.2. 433.4 and 433.45MHz verter £55.00 SN76660 FM quadrature detector 75p £249.00 C04031 At quad. 2•Input NOR gate tor tone-burst gen. 25p 14428 Converter £18.00 SOK.OH M Push-To-Talk Micro- NE555 Timer for tone-burst gen. or time-out Indicator 5515 43228 Convertor £19.50 phones £5.25 (To5); 741 (01L8) Op Amps 30p each Rectilinear pots multiturn, preset, p.c. mtg. 1294321 Converter £24.00 Microwave Modules counters 50 MHz £66.86 10, 20,25. 100, 250, 500, 2,5k, 3.5p each, any 5 + : 2-5P Microwave Modules 2 Metre Conver- BNC 50ohm tree socket.. 20p each; .12 for £1.45; 50 for £4.00 50M Hz Counter with Built-Ire 500MHz tors 2-4, 4-6, 28-30 MHz IF £20.25 Neon' Panel mounting. type JH8, 8rnm hole. 240Y, red, amber or clear: Pre-Sender £85.32 35p each. any 5 + : 30p. 10 .4-r 27P. M MC 144,28 LO 2 Metre Converter 500MHz Prescaler £27.00 Miniature. wire end (Hp each. 10 f: II ge. 100 t :4p. £2240 Bantez 2 metro Mobile aerials L.E.D's Pen& mounting, type JH5, 6.5mm hole, rod: 48p. green or amber: M MC 70 4 Metre Converter any IF £7.14 72 9 Any 5 less 10%. £20.25 Dante, Magnetic Mounts £10.40 Logic probo type JH 320, £11.95. M MC 432-70 CMS Converter any IF Jaybearn aerials ALL in stock Resistor Kite. El2 series, 22 Si to IM, 57 values. 5% carbon !Urn, ¡W or ¡W £24.75 PRICES INCLUDE 'VAT'• (please state). Starter pack. 5 each value (285) £1.40 Mixed pack, 5 each ¡W + ¡W (570) £4.65 PART EXCHANGE WELCO ME ACCESS OR BARCLAY CARD Standard pack, 10 each (570) £4.65 Giant pack, 25 each (1425) £11.65 I I King Street, Luton, Beds. 20907 Replenishments •vallable P1.259 UHF Plups + reducer 541p each. S + 60P 50239 UHF Socket panel mtg. 5.5p each. 5 + : 4-5P Mead Rechargeable cells U7 size, new, ft.05 each: 4 + St5p; 10 + 88p Slide switches, min. °PDT tiirp each: 5 + 149, 2 pote 3 position 220 each: S + .18p Toggle switches, rnln, lull range SP thro' to 4P C/O: sae list. G3LRB GAREX FM detector conversion ready «resembled with full fitting I n- •tructions. Tailor made, easy-fildeaignfor AM Cambridge. replaces squelch G3SMI board with minimum of other modifications, £5.40. Transistor Vanguard CB ELECTRONICS (AM257) version miih modified squelch circuit, O M. Suitable for most us with 450-470kHz IF. Sae detail.. UNIT 3, 771 O RNIS KIR K RO A D, PE MBER T O N INTER SERIES AD APTOR KIT. Super value. up to 40 dIfIerent corn- WIG A N W N5 SAT Phone Wigan (0942) 216567 binetions of BNC. UHF, N. TNC S C series connectors, male and female. T HE BES T IN THE N O R T H- WES T Complete in PVC wallet, £19.95. We are stockists of REVC O aerials tar V.H.F.-Arnateur, glider and P.M.R. Not just another new firm, but people with a wealth of bead types avalleble. technical experience and know-how relating to Authorleed distributor 10, J.H. As•ociatess Ltd., professional quality amateur radio techniques, requirements and servicing, co-Itches, Indicators and special products. who will always be pleased to advise and assist in all Lists available covering Revco 6 J. H. products. respects whether it be sales, service or information. EX-EQUIP. ITEMS (GU ARANTEED) Toroidal inverter transformers (with circuit.) HO W TO FIN D US £2.54 31)91602 /V'A60V 150rn(d"b A (d eledubled) (Ranger) £2.11 From M6 Junction 26 follow signs for Wigan A577. At first :kpol z vgg...ePuti11, . .irtpert HT choke suitable for 2-3kHz Inverters IkOts traffic lights (T junction) turn right towards Wigan. At next Mein. transformers, multItao Primaries traffic lights you are there BUT turn left, then 10 yards turn 515-450-0-450-515V 240mA, 50V, 50mA, 5V 2A, 5.3V 4A (12 lb) cs.se right BY TELEPHONE KIOSK and shop is slightly to 175-0-170V 90mA, 50V 50mA, 6-3V. 3-3A. 5V 2A (5.5 lb) £2.50 your right, Plenty of parking space. Distance from motorway O-146-232V 160mA, 26-5V I A 13-9V SA. 50V 50mA (10 ,5 lb) £3.95 mile. 135-0-135V, 50mA, 6-3V,3.3A £2.95 Auto 0-100-11 0-150-200.23,3240.250, 2(K)V A E3.2.5 From Wigan follow A577 for Skelmersdale to traffic lights HT chokes, 5H 8OrnA, 4H 240mA, 1.25H 350mA. 1.13H 125mA £1.25 at Pemberton (Ye Olde White Swan Hotel on your left). Butterfly trim mers large 2 x. 17 ,551, 2 x 1001 80p Turn right then 10 yards and right again by telephone 10 -7 IFT (valve tyoe)2I" x square double tuned 25p: 2 for 40p: 6 for 10p kiosk. Distance from Wigan 2+ miles. Closed Wednesday Mobile PSU 12V DC Input (floating for + or - E) transistor Inverter 170. 220 or 380V OC al 18OrnA. output. fully smoothed chassis section, sell- AT LIST PRICES SECOND HAND EQUIPMENT contained, fully wired and tested. with circuit £5.15 YAESU EOL 144 28 tvtr MK 1 £90 As above, but partly assembled (as cut out) complete with all com- UNIDEN Realistic DX 160 £80 ponents, circuit. finish-11.yourself £4.30 ELECTRONIC DEVELOP- PRICES ARE INCLUSIVE OF UK POST AND PACKING AN D VAT MENTS Edd‘stone EAI2 £195 NE W POSTAGE RATES INTRODUCED RECENTLY. BUT NO J. BEAM LTD. Drake R4C 01111 MS4 Speaker. 160m Xtal 6 3 INCREASES IN OUR PRICES YET NY GAIN Xtal 10 m £415 C.D.E. SEE US AT THE NATIONAL BELCOM Mail order only. Sole address for orders and enquiries S.S.M. AM ATEUR RADIO EXHIBITION GAREX ELECTRONICS WESTERN ELECTRONICS GRANBY HALLS, LEICESTER 7, NORVIC ROA D, MARS WORTH, TRING, HE RTS HP23 ILS F 0.0 PHONE CHEDDINGTON (STD 0296) 668684 Part exchanges welcome H.P. and credit terms S.A.E. all enquiries 6.30prn-Gpm AND WEEKENDS ONLY S.a.e. with all enquiries Oleele•

RADIO COM MUNICATION September 1977 729 VARIABLE CAPACITORS Direct drive. 5pf at 85p, 10pf at 75p, 20p1 al a5P. 30pf at 85p, 50pf at 85p, 125 -,- 1250 at 55p, 100 + 200pf at 55p. 180 180pf at 55P 500 50021 al 60p.

VARIABLE CAPACITORS with S.M. Drive. 300 -1. 30001 al 55P. 300 i 80001 at J. BIRKETT 55p. 400 + 500p1 at 55p, 500 + 500 -n 25 -1-• 25pf al 55u. MINIATURE BUTTERFLY VARIABLE PR ESET CAPACITORS Spindles easily extended. 25 lv 25pf at 50p, 25 n 2501 Wide Spaced at 55p, 38 x 38p1 at RADIO CO MP O NENT SUPPLIERS 60p, 38 0 38p1 Wide Spaced at 65P• Member of the ARRA ELETRET MICROPHONE INSERT WITH FET PR EA MP at £1 85. TBA 120S F.M. I.C. Untested with data at 6 for 60p. OPTO ISOLATORS 1E74 with data al 50p. FM TUNER HEAD w ill, conversion details to Aircraft Band or 2 Metres at £3. TANTALU M BEAD CAPACITORS •11,1 35 v.w., •1501 350.w., 33uf 35v.w.. lilt 350.w.. 2 2u1 25v.w., 2.2111 35v.w., 3-3g1 16v.w., 4-70 10v.w., 4.70 350.w . 100 Mallard C 280 Assorted Capacitors for 570. Sul 25v.w., 6-8W 250.w., 6 80 35v.w., IOuI 25v.w., 1510 20v.w., 201.416v.w..22gl CO M MUNICATION SERIES OF ICs Untested consisling 013 R.F., 1 . IF.. 16v.w., 33gf 16v.w., 4761 6.v.w. All al 99 each. 2 • AGC, 2 n VOGAD, 1 n Mike Amp, 2 n Double Balanced Modulator, 1 • Mixer. The 12 I.C's with data for £3. 10 ASS ORTED MULTI•TURN TRIM•POTS for 60P. MC 1458 DUAL OP-A MP at 40p each. 100 ASSORTED POLYSTYRENE CAPACITORS at 57p. PO WER TRANSISTORS 29 3055 at 55p, 29 3442 at 80p, BD 207 at 55p. CRYSTALS 10 • 5MHz at 50p, :OXAJ 600KHz at 50p, IOXAJ 7 or 8MHZ 3160p. X BAN D TUNING VARACTOR DIODES 1 to 2pF or 3 lo 4pF. with data at SOLDER•IN FEED THRO's 5.80, 3000. 10000. All at 20P do , £1 65 each. UN MARKED GOOD BEY SI TRANSISTORS at 6 for no. X BAN D GUNN DIODES with

100 0-10011A TUNING METER 11-' ... le al 90111• SPECIAL TUBULAR TANTALU M CAPACITORS 150 F 35v.w... at 10p. RCA CA 30890 I.F. I.C. at £1.40. SILICON DIODES BYX38-300. 300 PIV 6 Amp at 157 each. VHF DUAL GATE MOSFET LIKE 40673 al 330. 4 for £1.10.

VISCONEL CAPACITORS 0005g! 25Kv.w at 40p, •00051rf 75Kv,w. ot 50111. PLEASE ADD 20P FOR POST AND PACKING ON ORDERS UNDER £2 01016 flaw. at 25p. UNLESS OTHER WISE STATED OVERSEAS OR DERS AT COST. 25 THE STRAIT, LINCOLN LN2 IJF. Telephone 20767

HIRE OR BUY DREDHURSI ELECTRONICS VHF/U HF TzfRx's IC22A etc. From £6.50/month. MICRO WAVE MODULES TRANSVERTERS from £10.00 per month. FOR VHF IN THE NORTH WEST 2m Mobile Tx, Rx FM Quartz 16, 10 channels FDK SALE £169.00 MULTI II 2rn FM fitted 7 channels £201.00 MULTI Ull 70cm FM fitted 9 channels £249.00 ALL PRICES INCLUDE VAT MULTI 2700 2m all modo £489.00 SAE FOR DETAILS VFO for MULTI II £89.00 AC PSU for MULTI II £63.50 TM56B Scannen0 2m RX fitted 10 Channels eas.ao BOOTH HOLDINGS BATH Quartz 16 2m FM filled 10 channels £169.00 (Incorporating Ham Hire and Rent-a-Rig) Member of a T.A.F.A. ELECTRONIC DEVELOP MENTS 2m Ilnear 100W output £151.90 6 Golf Club Lane, Saltford, Bristol 712730 2rn transverter 28/144 £151.90 70cm linear 50W £151.90 G3X0D, G3NXU after 7pm Saltford 2402 VHF absorption wavemoter £19.00 G8DPH Windsor 51767 after 7pm YAESU FRG7 G,n coverage RX £162.00 ANTENN A SPECIALISTS ASP 677 2rn 1 wave £15.20 SPECIAL OFFER. CA3089E, £1.70; 293866, 70p; 293553, £1.00; 40673, 50p; ASP 629 2m 1 wave £8.57 295180, 30p; 39201, 6tip; 2ni. 12V FM TX board. Phase modulator 5kHz deviation ASPE 667 70crn 558 collinear £19.02 max. Size: 140mm a 82nen n 23rnin. HC25,'U Crystal. Multiplication X12. Sent ASPE 462 70crn 3dB collinear £8.14 for evaluation, P..f.P. 30o. 12V IW £20.2N4427, 70p; CA3001, El .50 ; 2145913. E1.511; ASP 655 2rn Base Stn. £16.25 295945 14W, 8dE1), E11.00; 295946. E M U; 295641, £4.01; ZTX327. 641p; 40964, £1.40; 40965, £1.50; 2713375. £2.00; 0C202, 10p; PT3500, £1.20; BLY33. £1.110; Constantly changing stocks of S:H ge•r —ring for details 295590. £4.51; 295591, £1.00; 293632, £2.00; 296080, £4.50; 296061, £5.511; JUBILEE CASH BONANZA' 296082, E.8.00; 296083, £9.00; 2N6084, 1E12.00; 2715642. 03,00: 295643, £11.00; Free draw ticket with every new FOR set purchased BYF50. 20p; BC108 16p; BC183L, 10p; BLW39, £3.00; 253478, 405: 3N202, 000; MPF102, 40p; 40441. 50p; BC167A, lip; BSY90, 30p; 293904, 10p: 293906, 10p; £1011 Cash Prize Integrated Circuit's: CA3007, Et »; CA3014, 811p; CA3018, 76p; CA3023, 80p; Soo Waters 41 Stanton Advert for full details MC1550G. 50p: MC1596G. 42.90; CA3000. £1.00; SL620/30C, ; MC174ICG. HP — PART EXCHANGE — ACCESS — BARCLAYCARD 600:293810. 20p; 292210, 40p; EILY55, £2.00; Transmitter tuning capacitor 7QpF. CALLERS BY APPOINTMENT ALL PRICES INC. VAT E1.110; 50239 sockets, 50p: N socket to BNC socket adapter. £2.50; N socket to N plug, £2.00; N plug to N socket, £2.00; HC2511J cryslal sockets p.c.b,, 15p: 2m 13V 25W TX, 6 channel FIC2 SU (X12) complete v. ith audio, £40; 2N2349(ex) WILLO WBROOK, SCHOOL LANE, BUNBURY, Sp Minimum order £1.1111. Mall ordm only, P.6 P. 20p. TARPORLEY, CHESHIRE. Tel Bunbury (082M 260708 HELLER ELECTRONICS Northern Distributor for Waters and Stanton G30QT lf Bi•SSOIT1 Way•,'Hounslow. Middx., TW5 OHS

730 RADIO COMMUNICATION Sepcember 1977 AMATEUR RADIO RETAILERS ASSOCIATION LEICESTER 111 M..e MAKE A NOTE OF THE DATES THURSDAY, FRIDAY AND SATURDAY OCTOBER 27, 28 AND 29 AT THE GRANBY HALLS 6th LEICESTER NATIONAL AMATEUR RADIO NE W OPENING TIMES - 10 am TO 6 pm EXHIBITION DAILY AD MISSION 30p

NE W AND BETTER CATERING

WHERE ALL THE LEADING AMATEUR RADIO RETAILERS PUT ON THEIR OWN EXHIBITION

Special Concessionary Tickets for Schools, Colleges and Radio Clubs. Any Further Details Tom Darn G3FGY QTHR

ClitC electronics 10 West Park London SE9 4 RQ NK Series Telephone 01-852 9397 CRYSTALS THE MADE TO ORDER CRYSTAL SPECIALISTS 7 4 1-OFF CRYSTAL PRICES Group Price Fundamentals I. 0-030 to 0.099MHz 100ppro £14.25

2. 0.100 to 0.359MHz 10OPPm £5.75 3. 0.370 to 0.730MHz 103ppm £10 .00 Pneumatic 4. 0.731 to 1.499MHz 100opm £9.75 5. 1.500 to 1.999MHz 30pPm ct-es 6. 2-000 to 3.999MHz 3OPPni £3.00 7. 4.000 to 20 .999MHz 30ppm £2.85 Telescopic 8. 21000 to 24.000MHz 30nprn £3.25 3rd Overtones 9. 23.000 to 54.99.2MHz 30ripm £2.125 51h Overtones 10. 55.000 to 104.999MHz 30OP. £2.95 lee,) Hilornasts 11. 105.000 to 119.999MHz 30pom £8.25 . 120000 to lao.000mHz roppm £0.50 5th, 7th and Ott. Overtones 13. 130001 to 216.000MHz 10ppm £10.2.5 Unless otherwise requested fundamentals will ho supplied with 30oF load capacity and overtones for series resonance operation.

HOLDERS 0-030 to 0200 MHz HC13,11, 0.170 to 196.000MHz HCGU. 4007 to. 216 -COOMHz HC18 or FIC25;12. Prices on opplisation for other holders. DELIVERY Groups 1 to 4, 12 and 13-6 to 8 weeks. Groups 5 to 11-4 to 6 weeks. DISCOUNTS 5% mixed frequency discount for 5 or more crystals within any Price group. For orders of same frequency and spec discounts start at 5 off in groups 1. 4, 12 and 13.1n all other groups discounts start nt 10 all. Special rates for bulk purchase schemes Incl free supply al xtals tor UK repeaters. Extended by a standard vehicle foot pump. Easily CRYSTALS FOR POPULAR VHF TRANSCEIVERS retracted for severe weather conditions. Elegant Crystals supplied in approx. 5 weeks to any slated frequency for the folio...ding VHF Tx's: Heathkil, [corn, Ken, Standard. Trio and Yaosu. Price £2.50 per crystal. when extended - unobtrusive when retracted. LOW FREQUENCY STANDARDS (8% VAT) 1C(IiiHz in HC131U. Price £2.95. 1000kHz In FIC61). Price £2.80. CRYSTAL SOCKETS FIC0U and HC2511. Price 16p. HILO MAST LTD MINIMU M ORDER CHARGE £2.00 PRICES ARE EX VAT - PLEASE AD D 12% UNLESS OTHER WISE STATED The Street, Heybridge, All prises include postage to UK and Irish addresses. Crystals supplied to any specification for industrial, mobile radio or marine use, etc. State equiPmenti Maldon, Essex, C M9 7NB. Tel: Maldon (0621) 55480 specification when enquiring. Please send sao with all enquiries.

RADIO COMMUNICATION September 1977 731 AMBIT international—the radio component source Usted here is a selection of popular components for the radio Now you can get all constructor/enthusiast. Our latest catalogue Includes more In- formation on our AM/FM tuner modules—with all those hard-to-get bits, like coils, filters, trimmers etc. 2-metre frequencies at TOKO coils: Ambit now holds over 200,000 in stock AM IFTs for 455/470kHz 1st, 2nd and 3rd £0.30 FM IFTs for 10.7MHz Also detectors £13-33 the flick of a switch. Ratio discriminator coils for 455kHz or 10-7MHz £1-35 Tunable chokes of 2, 3.5, 7, 11.8, 23, 38mH £0-33 S.18 molded VHF coils: 0-09, 0-12 and 0-18uH ex-stock £0.33 Special molded spiral formers with two slugs and can £0.25 Various RF and oscillator coils—see catalogue for details. TOKO FILTERS: Low cost and high performance MFH4117MFH7IT 4 or 7kHz Bandwidth. 455kHz mechanical filters with matching transformers £1.95 0« CFT series ceramic filters for 455kHz 6 and 8kHz BW £0-55 2kHz 6 element mechanical filter for 455kHz SSB Tx/Rx—'MFL' £9.95 FOIL trim mers—Mullard and Dau types 1-8pF, 3-30pF, 7-45pF in 7-5mm diameter: 18, 23 & 26p resp. 7-60pF 10mm diameter type £0-26 VARICAP DIODES —VHF and MF/HF wide range tuning diodes BA102-30p; BA121-30p; BB104-45p; MVAM2—£1-35 NEW MVAM125: 20 to 400pF with 25V bias available in singles or sets for multi stage tracking 90p each, 3 for £2-65. ICs for Radio: The best and most recent popular types: HA1197 AM system, though suitable for SSB and NBFM IFs. 80cIB AGC, meter stable to use £1.40 HA1137 FM IF system slm to 30E9 with better mute M-95 TBA651 Linear RF/IF gain block with AGC £1.81 The new frequency TBA120 FM detector block with gain £0-75 Please remember to Include VAT (usually 12-5% except where marhed *) and our nat synthesized 2-metre ISp PdP charge. Catalogue 400 Inc. Please scram ploy engUldes with an SAE. Price fia M OM, available FOC with en SAE. transceiver from Heathkit. 37 High Street, Brentwood, Essex, CM14 4RH Telephon• (0277) 216020 after 3pm If possible—Ins. The new Heathkit 11W-2036 gives you true digital frequency.synthesis. For real operating versatility. QUICK SERVICE IN FM CRYSTALS All 2-metre frequencies in the band are available. 70cm Channel SUB. St.120. RBO. RB2, RB4, R136. RBIO, 11514, For Starphones: Tx 24MHz range. Its 34MHz range, In HC25/U And operation just couldn't be easier. Y(m just select the For Pocketphones: Tx 12MHz range, Rs 84MHz range, In HC18/11 2 metre. Raynet channel 145$, S32: frequency by flicking the front panel switches. And should Ts ranges: 6, 12,18MHz In FIC25111, 4, 8MHz In HC6IU you inadvertently select an out-of-band frequency, the Rx ranges: 14. 44, 52MHz In HC25/U, 10, 44MHz In HC6IU In the some ranges: SO. 520-4, RI-R8 from stock. transmitter simply wont key. Inclusive pace £2.90 each 10% discount on 10 or M000 The HW-2036 gives you a very clean, minimum 10 watts Made-to-order crystals 2-105MHz, 3Oppm £3.60 inclusive, 6 weeks deliver/ output and sensitivity is an outstanding 0.5 'N. Giro 35 563 4007 SAE please tor Ilota Phone 04 868 7507 For more information on the HW-2036 and all our other HARTLEY CRYSTALS Green Lane, Milford, Godalming, Surrey GU8 5BG kits, post the coupon and we'll send you our latest catalogue. Then you'll have all the facts at your fingertips. G2DYM AERIALS Heath (Gloucester) Limited. Dept. PC-97 Bristol Road, ANTI-T.V.I. AERIALS INDIVIDU ALLY DESIGNED BY EX- Gloucester. GI.2 6F.E.Tel: Gloucester (0452) 29451. B.B.C. TRANSMITTER AND AERIAL ENGINEER. ALL CUS- TOM BUILT FOR THE TRANSMITTER OR S.W.L. G5RV's, G2DYM's, WIDEBAND S.W.L. TYPES, DESIGN AND AD- HEATHKIT VISORY SERVICE. Details-7" ,10 S.A.E. and 3 9p stamps. LAM BDA ANTENN A STU D FAR M, W HITEBALL, Better built because you build it yourself. W ELLING TON, SOMERSET. Fro:Heath (Gloucester) Limited, Dept RC-97,

I Gloucester, GL2 6EE. Valves from the Junk Sale? Schlurnberger I Please send me a Ileathkit catalogue. A Second rate valve makes for a Second rate signal. (Splatter I enclose lip stamp for postage. is antisocial—and illegal.) If your linear uses 4CX series valves, we can supply types 250B, 250R, 350A (also bases and I Name chimneys) brand new, guaranteed 3,000 hours, ex stock. Contact G8M DF, P.O. Box 10, STAN MO RE, Middx; 01-954 IAddress 1609. We also provide a full (and free!) technical enquiries and after-sales service: throw the difficult questions at Postcode G4FRX on 01-602 5855. CA MBRIAN ELECTR ONICS—STOCK- L_ ISTS OF EIM AC PRO DUCTS.

732 RADIO COMMUNICATION September 1977 DECCA/K W equipment continues to be valued in the U.K.and DECCA/MM Overseas Amateur Radio Markets. equipment area Rit ewer eats teem's/

KW UM MONITORSCOPE K W 212 • Monitor your transmitted KW 202 Receiver • One of the Rnest Amateur Band Receivers on the market 'Waveform 10-160 metres. • ssa filler and ' cy multiplier. • Excellent sensitivity and stabliihr• • Two speed I unIng 10-163 metres. • Can be left permanently In KW Ill ANTENNA TUNING SYSTEM antenna geed. • Incorporates • Two-tone generator incor- E-2 Match. porated to ensure optimum • Antenna switch. • SWRTFIF Linearity for SSB. Power meter dummy load. • A further safeguard for your • High power PA tubes. version KW 10 I also available. serving RadioA mateurs worieble AMATEUR RADIO PRODUCTS • Easy terms on equipment available DECCA COMMUNICATIONS LIMITED over 12,18 or 24 months Grampians Road, Otford, Sevenoaks, Kent TN14 5EA. Telephone: Sevenoaks (0732) 50911

NEW! SAMSON ETM-3C antenna specialists C-MOS KEYER 11.1.A battery drain — Why switch off? THESE ARE THE BEST—FORGET THE REST!

• Self-completing dots/dashes/spaces. 911 Can be used MOBILE ANTENN AS AN D MOUNTING OP TION S either as normal electronic keyer or as an iambic-mode Compare these prices squeeze keyer. 8-50 wpm. • Constant 3:1 dash-dot • up to 207, discount ratio. • 6 C-MOS ICs and 4 transistors. • Plug-In PCB. ASP 201 1-wave 108-512MHz £2.58 • Long battery life—typically 1y.A drain when idling— ASP 629 i-wave 130-174MHz, 3dB gain £6.61 Bullt-In batteryholder for 4 x 1 -5V batteries (but will work ASP 677 1-wave 130-174MHz, 3dB gain £11.95 over 3-10V range). • PCB has both a reed relay (250V, ASPE 462 1-wave 420-440MHz, 3dB gain £14.95 0-5A, 25W max) and a switching transistor (300V. 30mA max) ASPE 667 Colinear 420-440MHz, 5dB gain £6.50 —either keying method can be used • Has the well-known K220 nag mount with cable fits 629, 677. 667 £7.69 fully-adjustable Samson precision keying lever assembly. K220A mag mount with cable fits 201, 462 £7.19 • Operate/Tune button. • Sidetone oscillator. Grey • K203 trunk lid mount fits all £3.70 case 4" x x 6. £63.88 ASP 332 gutter mount fits 629 £7.10 ETM-4C ME M ORY KEYER: As ETM-3C but with 4 Mem- ASPR 332 gutter mount fits 677, 667 £7.10 ories (2 combinable). K126 shock spring £4.95 BUILT FOR DEPEN DABLE MARINE & CO M MERCIAL SERVICE BASE STATION ANTENN AS JUN KER PRECISION HA ND KEY. A superbly engineered straight key used for many years by professionals afloat and ASP 655 1-wave 130-174MHz, 3dB gain £14.00 ashore. With this key you can't help but send good morse. Free- ASP 659 UK Colinear 420-440MHz. 5dB gain £15.00 standing—no screwing down. Front and back contacts—fully- HM 680 UK Colinear 144-146MHz, 6dB gain` £60.00 adjustable gaps/tension. Key-click filter. Hinged grey cover. HM 700 UK Colinear 430-440MHz, 9dB gain' £92.00 £28.64. HM 701 UK Colinear 430-440MHz, 12dB gain* £125.00 BAUER KEYING PAD DLE. Single-paddle unit on 11' x 2' N.B. All gains relative to i-wave whip base for home-built El-bugs. Adjustable gapsitensions. £9.97 88mH TOROIDS for CW. RTTY, SSTV filters, 90p. each TERM S: cash with order, callers by appointment only. Add 90' AU DIO PHASE SHIFT NET WORK S octal based. 121% VAT to all prices. Add 50p p ÷p to all except items marked • All prices postpaid UK and include 121% VAT. Please on which carriage is £2.00. send stamp with enquiries. SPACE MARK LTD. Commercial Communications Thornfield House, Delamer Road, Altrincham, Cheshire. 17 Lancing Road, Luton, LU2 &JN Tel: (0582) 21884 (Tel : 061-928 8458)

RADIO COMMUNICATION September 1977 733 CLASSIFIED ADVERTISEMENTS SITUA TIONS VACAN T

Private advertisements 15p per word, minimum £3.00. Trade advertisements 25p per word, minimum £5.00. Box Number 75p extra to wordage or minimum. Semi-display 1/12 page (1r X 3") £18.00. AERIAL DESIG N 1;16 page (j X e) £13.00. Please write clearly. No responsibility accepted for errors. ENGINEERS Latest date for acceptance-41h of preceding month. All classified advertisements must be prepaid. Copy and remittance to: C. C. LINDSAY. 2 Leyburn Gardens, Croydon CRO 5NL. Tel 01-686 5839, A Micro wave C o mpany on the H a mpshire coast Members Ads must be sent to the Editor at Chelmsford. requires a Senior D esign Engineer and a D esign Engineer experienced in the develop ment and design FOR SALE of octave band width and m ulti-octave V H F and U H F G.I. AM ATEUR SUPPLIES GI3ZIA for Trews, Rs Tx, Antennas, aerials and arrays for defence applications. Mics, etc. Trade-in's welcome. Large stocks at 10 Church Street, Enniskillen, N. Ireland. Tel: (0365) 22955. At least 12 years relevant experience is required for A DATE WITH SUSAN, GB3SN repeater handbook. Essential the m ore senior appoint ment, and 8 years relevant reading for all users of the repeater. Send 50p large SAE to U.K. experience for the other appoint ment. F.M. Group (Southern), 12 Meadow Way, Aldershot. Hants. Experience and proved innovative ability are the BARGAIN. LOG BOO KS 65p EACH. Your callsign over-printed if you order four. Beauprint, Meltham Road, Honley, Huddersfield. para mount qualities that w e are seeking, for mal SHIBA DEN SV610 (time lapse) r VTR, £165. Shibaden receiver acade mic qualifications are not necessarily essential monitor, £125. Pye 22 receiver monitor. £35. National 3020 r VTR but would be an advantage. (edit.), £150. Sony 5600P colour VTR r, £275. 19' Rank sound/video Successful candidates w ould w ork in very pleasant monitors, £28. 25' Pye colour studio monitors. RGB input, £90. 22* Swedish Pye colour TV, 625 line VHF, UHF (Spain on channel 11). surroundings, and their salaries w ould reflect their 1 and e video tape also available. G3OLV. Telephone 01-669 2611, experience and their responsibility. 35 Sandy Lane South, Wallington, Surrey. QSL CARDS. Sae for samples. Bailey d, Co, 35 Whitecross Road, For further details, please write to: Weston-super-Mare. QSL AN D LISTENER'S CAR DS. A prompt and economic service. SAE for samples G3VZF, 5 The Close, Radlett, Herts. M r D. W. Ford, RTTY PICTU RE PERF. TAPES. Hundreds to choose from. M anaging Director, Standard Murray paper tape. Send 9- • 4' sae for free catalogue. Southern Micro wave Laboratories Limited, M. Watson, G3WM Q, 74 Bow rons Avenue. Wembley, Middx. 103 Station Road, QU ALITY QSL CARDS. S.a.e, for samples by return post H AYLIN G ISL A N D, H a m pshire P011 OEE (including Silver Jubiless styles—if requested). Quick delivery. Compalith Printing Services, 115 Promenade, Cheltenham, Glos. GL50 1NW. FT401B TRA NSCEIVERS, £320, list £400. High-Gain TH3-JR, £75, list £110: both unused. Radio compass rotator and indicator, suitable small beam, £10. 5 Lomeshaye Road, Nelson, Lancs. A MTEST for radio and electronic test equipment 99% British I N D E X T O A D V E R TI S E R S makes. Large range. Pocketphone batteries. Large s.a.e, for details. 55 Vauxhall Street, Worcester WR3 8PA. Aero & General Supplies .. 728 Hilomast Ltd .. 731 TELEPRIN TERS: Creed 7B's with perforators, £25. Creed 54's, Aircall Ltd .. 73.5 D. P. Hobbs Ltd .. .• 729 £30. Creed 75 from £40 (depending on facilities required). Gears, AJH Electronics Cover iv Inlegrated Circuits Unlimited .. 723 accessories and handbooks. Please write or telephone G3OLV, Amateur Electronics .. .• 671 Interlace Quartz Devices Ltd .• 727 01-669 2611. 35 Sandy Lane South, Wallington, Surrey. Amateur Radio Exchange 728 Jantes & Marlin Ltd...... 727 MISCELLANEOUS Amateur Radio Retailers Assn 731 Johns Radio 721 Ambit International 732 K W Amateur Radio Products .. 733 COU RSES —RADIO AM ATEU RS EXA MIN ATION. City and A. L, Bailey 728 London Communications Ltd .. 735 Guilds. Pass this important examination, and obtain your G8 B. Bambe.r 736 Lowe Electronics .. 662:3 licence, with an RRC Home Study Course. For details of this and J. Efirkett 730 Microwave Modules Ltd .. 673 other courses (GCE, Professional Examinations, etc) write or Booth Holdings Bath 730 Modular Electronics .. .. 672 phone: The Rapid Results College, Dept JT1, Tuition House, Brodhurst Electronics 730 Mosley Electronics Ltd .. 721 London SW19 4DS. Tel: 01-947 7272 (Careers Advisory Service) or BrIcom 722 William Munro (invergordon) for a prospectus only ring 01-946 1102 (24hr recording service). Cambridge &its .. 728 Cover II PATENTS and TRADE MARKS —Booklet on request. Kings Calronics Ltd • . 722 Partridge Electronics Ltd .. 724 Patent Agency Ltd (B. T. King, Reg Pat Agent)-146A Queen CB Electronics .. 729 PM Electronic Services .. 725 Victoria Street, London EC4. Tel: 01-248 6161. Telex 8833805. C & C Electronics .. 731 DM70 Electronics Ltd .. 724 Established 1886. Chase Electronics Ltd 734 Radio Shack Ltd .. 675 Colornor Electronics .. 728 RT & I Electronics .. 722 SITU ATIONS VACANT Commercial Communicalions 733 SEM Electronics 670 Cherchlown Electronics 726 Southern Microwave Laboratories 734 R.F. DESIG N ENGINEER Crayford Electronics 725 South Midlands Datong Electronics 726 Communication Ltd .. 658;661 Radio frequency design engineer required for va7ied and Ashley Dukes 721 Spacemark Ltd .. 733 interesting work in a small but well equipped company British National Radio & Elec- Standard Telephones Ltd .. 735 specializing in the design and manufacture of RF inter- tronics School .. 726 Stephens-James Ltd ., .. 727 ference measuring instruments and systems. Gates Electronics .. .• 779 Thanet Electronics .. Salary will be commensurate with experience and ability but G2DYM Aerials 732 TMP Electronic SuOPlies • • 725 the successful candidate should be able to negotiate a GVVM Radio Ltd .. 724 Reg Ward & Co Ltd .. .. 722 salary in excess of £6,000 p.a. Ham-Spares .. • . 728 Waters & Stanton Electronics For further details please contact: Hartley Crystals 732 Western Electronics (UK) Ltd CH ASE ELECTRICS LIMITED 727 Heath (Gloucester) Ltd • 732 W. H. Westlake .. 674 Church Lane, Teddington, Middx. Tel: 01-977 0251:2 Holler Electronics .. 730 Yarns Musen Co Ltd • .

734 RA DIO COM MUNICATION Septe mber 1977 SITUATIONS VACANT

IF Research Engineers

At STL our specialist team approach has successfully pioneered new solutions to long-standing problems in the radio field and we're now expanding to apply these developments to different areas. The new teams we're establishing need Engineers, men and women with experience of RF circuitry design, to work on state-of- the-art projects in VHF and UHF. Your sound, practical knowledge of radio should be coupled with the analytical competence necessary to validate your work and the ability to think creatively. You will probably have a good degree or equivalent and will have been actively engaged on RF projects for a few years. The SIL environment is stimulating and encourages the development of every individual's ideas. As the main research centre for ITT's worldwide business both the scope of the projects and the back-up available are second to none-with salaries and benefits to match. These include generous expenses for relocation.

Please write or phone for an application form, quoting Ref. 63/77, to: V. Hartridge, Standard Telecommunication Laboratories Limited, London Road, Harlow, LEssex CM17 9NA. Tel: Harlow 29531.

RADIO-TELEPHO NE BENCH RADIO TELEPHONE ENGINEERS AND kte UHF PAGING ENGINEERS FIELD SERVICE ENGINEERS REQUIRED TOP SALARIES FOR TOP ABILITY London's fastest expanding, independent, radio-telephone company needs more engineers. FOR BENCH WORK AT OUR If you have experience in mobile VHF ring NO W! LAMBETH WORKSHOP 01-328 5344, Mike Rawlings or Bill Clarke Contact Bob Davis on 01-735 5552. London Communications AIRCALL LTD. (Equipment) Ltd 30 Ekundary Road, inn4on. IlW8 01 •32E1 534 4 18a Lambeth High Street, London, SEI.

RADIO COMMUNICATION September 1977 735 TE R M S OF BU SINES S: C A S H WI TH O R DE R, MINIM U M O R DER OF £2.00. ALL PRICE S NO W INCLU DE PO S T 8. P A C KIN G (UK ONLY) B. BANDER ELECTRONICS EXP ORT ENQUIRIES WELCOME CALLERS WELCOME by APPOINTMENT ONLY DEPT RC, S STATION RD, LITTLEPORT, CAMBS, CB6 IQE Please enclose stamped addressed envelope with ALL Enquiries TEL: ELY (0353) 860185 (TUESDAY-SATURDAY) PLE A SE A D D V A T A S S H O W N

ALL BELOW -ADD 8% VAT ALL BELOW -ADD 8% VAT ALL BELOW -ADD 8% VAT

CALIBRATOR XTALS 100KHz 1MHz In One 10X can PLASTIC PROJECT BOXES with screw on lids (in RED LEDs (Min. (aye) 5 for 70p. £.00 each. Black ABS) with brass inserts. 13V DC RELAYS. 4 pole change-over (double con- BINOCULAR LENSES. 21' cite. x 6' Focal length, Good Type 0401 approx. 3". 2rx 409 each. tacts). (will work hem I4-24V DC). Brand New, boxed, Quality Achromats, but rejected because of small Type NB) approx. 31' x 21' x 1)' 50p each. good quality, made by AEI 40p each. scratch or chip at edges, £1.25 each or 2 for £2.00. Type NB3 awes. 41' x 31' y II' 1109 teach. SLIDER SWITCHES, 2 polo make and break, (or SMITHS CLOCK MOTORS. 200-250V 50Hz 2 watts. QUARTZ-XTAL CONTROLLED CLOCKS, 9 to can be used as 1 pole change-over by linking the 1 Rev. every 2 mina., 3 hole fixing. spindle, £1.00 12V OC at approx. 3mA required. Dial size approx. two centre Pins) ,t for 50P. each. 2', depth et unit approx. 2', Not In cases. unit only. SMART MIN. RECTANGULAR PUSH TO MAKE SLO W MOTION MOTORS, 120V 50Hz 1RPM, Size smart modern appearance, black face with white S WITCHES, black rectangular surround with white approx. 2" d, 1r deep, with i'spIndle. 60p each or 2 tottering, 12 hr, with second hand, end red hour and rectangular button, overall size 12 x 17mm, 3 for for £1.00. minute hands (Cost over £40 to ProdUCe) £10.00 each 50p. COMPUTER GRADE ELECTROLYTICS, Screw ter- while stocks last, tested before despatch, RYE SSB125T P.C. BOARDS (Ail brand new with minals. 20,000nifd at 45V (ex-equipment) 2 for £1.00. OSMOR REED RELAY COILS (for reed relays up to circuit diagrams) I2V DC. NEW PCBs For RYE LYNX TV-CAMERA. ) dia, not supplied) 12V, 500ohm coil, 2 for 50p. SSB RF FRONT END PCB. 4 channel. 3-15MHz. RF STABILISER PANEL (AT26152) £3.00. PERSPEX TUNER PANELS (for FM Band 3 tuners) and Mixer stages, ant in. 1.4MHz out £2.00. VIDEO PCB (AG58314) £5.00. marked 88-108 MHz and Channels 0-70, clear number SSB CHANNEL OSCILLATOR PCB. 4 channel 6BW6 VALVES (BRAND NEW). 85p each or 2 for rest blacked out, smart modern appearance, size with trimmers, tor 4 Fundamental slats (2 stage) £1.00 £1.50. approx. fIr z tr, 2 for 35p. SSB AUDIO AMP PCB ( 3 stage) £1.50. MIXED COMPONENT PACKS. containing resistors. SOB (1MHz OSCILLATOR & AGC AMP PCB. SUB-MINIATURE ROTARY SWITCHES, 4 a 5 way capacitors, switches, pots, etc. All new, and hundreds (less stall ELUL make contacts, Size approx. r dia. 1' deer). 71r. 40Indier of items, £2.00 per pack, while stocks last. umtrED SUPPLY ONLY ORDER NOWI 50p each. PROGRAM MERS (Magnetic deviCeS) contain 9 micro switches (suitable for mains operation) with 9 relating 4MHz XTAL PACKS BARGAIN PACK OF LOW VOLTAGE ELECTRO- cams, all individually adjustable, Ideal for switching (10 assorted Hais between 4MHz and 5MHz), our LYTIC CAPACITORS. Up to 50V working. disco lights, displays, etc., or industrial machine selection only. £1.00 Pack. Seatronlc manufacture. Approx. 100 £1.50 per pack Programming. (Need slow motion motor to drive cams. ALU.SOL ALUMINIUM SOLDER (made by multicore) (+120% VAT). not supplied) 9 switch version, £1.50. Solders Aluminium to itself or Copper. Brass. Steel. Nickel or Tinplate, 18SWG with multicore flux, with TUNED COILS, 2 section coils, around 1MHz. with a PLUGS & SOCKETS instructions. approx. lm coil 40p Pack. black smart tuning knob, which moves an internal Large reel £2.75. BNC PLUGS (ex-equip) 5 for £1.50. core to vary the Inductance, many uses, easily rewound, SOLDER SUCKERS (Plunger Type) N-TYPE PLUGS 50ohrn 60p each, 3 for £1.50. 3 for 509. Standard Model ES.DO. Greenpar (GE30015) Chassis Lead Terminations Skirted Model £5.50. (These are the units which bolt on to the chassis, FULL RANGE OF BERNARDSiBABANI ELEC- Space Nozzles 60p each. the lead is secured by screw cap, and the inner of TRONICS BOOKS IN STOCK, S.A.E. FOR MULTICORE SOLDER the coax passes through the chassis). 30p each. 1 Size CISAVIlt Saybit, 113SWG Sop, LIST for MAO. IXo• (1.11b) 60/40. 20SWG on Plastic Reel, £3.00. PI.259 Plugs (PTFE) Brand new, packed with reducers. WELLER TCP2 and PU2D PSU. Temperature con- NEW FOR THE VHF CONSTRUCTOR. A range of 65p each or 5 for £3.00. trolled solderinp Iron, with matching Power Supply lured circuits on formers with slugs and screening S0239 Sockets (PTFE) Brand new. (4 hole fixing type) Unit, containing sponge and spring stand. £30 .00 . cans. Frequencies quoted aro approximate, and 50p each or 5 for £2.25. range can be greatly extended by using varying capacitors in parallel. VALVES SPIRALUX Toole for the Electronic enthusiast ... SAE Type S (j" square, dumpy type) for list. Type SA 20 to 30MHz (when 3301 fitted in parallel) QQV03 '20A See equipment) £3.00. Type SD 135 to 175MHz (with link winding) QQV03.10 (ex equipment) 75p or 2 for £1.20. HEAVY DUTY RELAYS. 24V DC operated (will work Type M (Min. r square trees) DET-22 fez equipment) 2 for £1.00. on 18V) 3 heavy duty make contacts (around 10A Type MA 19 to 28 MHz (when 93pf fitted in parallel) Eff3H13 (ex equipment) 2 for 50p. rating 4. 4 change over contacts + 1 break contact. Type MB 22 to 32MHz (when 33pf fitted In parallel) All tho above valves are untested. except for healers, New, complete with mounting braeltet(ideal for switch- Type MC 25 to 35MHz (when 33p1 fitted in parallel) and no guarantee al percentage of emission is given, ing HT on Linen's). Many uses for this high zombi), unit. £1.50 each. Tree MD 38 to 50 MHz (when 330 fitted in parallel) Sorry, no returns. Type ME 45 to 60MHz (when 33p1 fitted In parallel) MULLARD 115A2 85V STABILISER VALVES (brand Type MF 100 to 200MHz (without slug) when 0 to 300 new) 70p each or 2 for £1.20. variable fitted in parallel) ALL BELOW -ADD II2+% 2icy VAT All the above coils available in packs of five only TRANSISTORS TUNERS Mullard Type ELC1043,05 Brand New, (Same type) at 50p per pack of 5. PNP Audio Type 705 Transistors, 12 for 25p. TV plugs (metal type) 4 for SOP. A NEW RANGE OF QUALITY BOXES BFY51 Transistors, 4 for 60p TV sockets (metal type) 4 for 50p. INSTRUMENT CASES. BYX 38 ,300 Stud Rectifiers. 300V al 2'5A, 4 for 80p. TV fine connectors (back-to-back skt) 4 for 50p. Aluminium Boxes with Ilds. BCY72 Transistors. 4 for 50p. 195)(20. (VHF oscfrnult.) 3 for 50p. 3 pin Din plugs, 4 for SOP. AB10 4 11, 60p Din 3 pin Line Sockets, 15p each. AB13 6 4 2 80p BC108 (metal can) Olor 50p. Din Sockets 5 pin, 270 deg. 4 for 50p. AB14 7 e 5 x 2) £1.00 ROC 108 (plastic BC 103) 5 for 50p. Din Speaker Skis, 2 pin, 4 for 30p. AB15 e 6 , 3 £1.30 6E152 (UHF amp/mixer) 3 for 50p. 2N38I9 Fet. 3 for 80p. T WIN IF CANS, approx. 1' x + 1' high. around A1318 10 e. 7 x 3 £1.50 3.5 to 5 MHz. 2 separate transformers in one can. AB17 10 e 41 e 3 £1.30 BC148 NPN SILICON 4 for 50p. Internally screened, 5 for 50p. AB25 6 e 4 , 3 £1.00 BC158 PNP SILICON Olor 50p. Vynal Coated Instrument Cases. BAY31 Signal Diodes 10 for 35p. Blue Tops and White lower sections. Very smart BAI21 Valletta Diodes.. for 50P. ELECTROLYTIC CAPACITORS Il nish. DIECAST BOXES. We still stock these, but owing Dubliner Electrolytic., 50uF. 450V, 2 for 50p. WBI 5 x x 2( 60p to frequent price rises been our suppliers, and costly Dubillier Electrolytic', 100i1F. 275V, 2 for 50p. w82 0 y 4) .< If £1.10 postal charges, it has been found impossibielo publish Plessey Electrolytics, 470e, 63V. 30e, 50p. WB3 8 x 5 x 2 £1.00 up-to-date prices on these items. Please ring or write TCC ElactrolytIcs. 1000uF, 30V. 3 for 809. V,/ B. 9 x < 2) £I.80 (with SAE). for latest mail-order prices. Dubillior Electrolytics, 5000mfd at 35V, 50p each. W OO 11 x 3 £2.110 ubillier Electrolytic'. 50(1011F at 50V, 60p each. AEI CSIOBiR MICRO WAVE DIODES ruy to X-Band, WEIS 11 x 7j, x £2.25 ITT Electrolytics. 6800mId at 25V. high grade, screw max, noise figure 8.5d8 at 9.375GHz. 80p each. WB7 12 81 e 5) £240 terminals, with mounting clips. 50p each. 14 OIL REED RELAYS, 5 to 12V DC, 450 ohm coil. WB353 8 x 51 x 3) £2.00 Designed to work directly horn TTL logic, single VIDICON SCAN COILS (Transistor type, but no dolo) Polo Changeover, Contact ratings. 23V ¡A. 1W. A LARGE RANGE OF CAPACITORS AVAILABLE complete wilh vidicon base £6.50 each. Brand new. £1.75 each. AT BARGAIN PRICES. SAE FOR LIST.

736 RADIO COMMUNICATION September 1977 RADIO COM MUNICATION September 1977 iii

PUBLICATIONS OBTAINABLE FRO M RSGB RSGB members can obtain a 10 per cent discount on the prices listed below (excluding Ham Radio Magazine and Ham Radio Horizons). To obtain the discount, deduct 10 per cent, calculated to the nearest penny, from the total value of the order (using the latest price list) and enclose a remittance for the balance. Also enclose an address label (roes a recent Radio Communication wrapper as proof of membership.

RSGB PUBLICATIONS OTHER PUBLICATIONS Technical books American Radio Relay League Amateur Radio Awards . . £2.15 Antenna Book (13th edn) . . . . . £4.08 Amateur Radio Techniques (5th edn) £3.55 Course in Radio Fundamentals . £2.93 Guide to Amateur Radio (16th edn) . £1.38 FM and Repeaters for the Radio Amateur (Out of stock) Morse Code for Radio Amateurs . 54p Hints and Kinks . . , . . . £2.58 NBFM Manual . £1.38 Radio Amateurs' Handbook 1977 (Paperback) (041 of stock) RSGB Amateur Radio Call Book 1977 £2.35 Radio Amateurs' Handbook 1977 (Hardback) (Out of stock) RAE Questions and Answers . . £2.00 Ham Radio Operating Guide . . . . . £4.44 Radio Amateur's Examination Manual . £1.60 Single Sideband for the Radio Amateur . . £3.85 Radio Amateurs' Examination Revision Notes . 869 Specialized Com munication Techniques . . £4.04 Radio Com munication Handbook 5th edn, Vol 1 . . £9.36 Understanding Amateur Radio . . £3.84 Radio Com munication Handbook 5th edn, Vol 2 . . £8.12 VHF Manual . . £4.08 Radio Data Reference Book . . . . £3.65 Electronic Data Book . . £4.04 Service Valve and Semiconductor Equivalents . . 489 Teleprinter Handbook ...... £8.89 Radio Amateur Callbook Inc Test Equipment for the Radio Amateur (Out of print) American Callbook (USA listings) 1977 (Out of stock) TVI Manual (Out of print) American Callbook (DX listings) 1977 (Out of stock) VHF/UHF Manual . . £6.82 World Atlas (Amateur radio prefixes) . £1.72 World at their Fingertips (Paperback) £1.63 World at their Fingertips (De-luxe) . £2.76 Radio Publications Inc Beam Antenna Handbook . £4.44 Log books Better Short Wave Reception (3rd edn) . £3.42 Standard Log . . £1.34 Cubical Quad Antennas . . . £2.77 Receiving Station Log . £1.46 Simple. Low-cost Wire Antennas . . £3.46 Mobile Mini-Log . £1.03 De-luxe Log . . £3.00 "73 Magazine" publication SSTV Handbook . . Maps, charts and lists . £3.19 Countries List/HF Awards List • 25p Great Circle DX map (in tube) £1.29 Miscellaneous £1.00 Oscar map (in tube) . . . . 43p International VHF FM Guide . OSCAR-Amateur Radio Satellites . £4,20 0TH Locator map Western Europe) (in tube) • £1.15 RTTY the Easy Way . . £1.02 0TH Locator map .Western Europe) (on card) 57p Radio Amateur Operators Handbook £1.11 RSGB Amateur Radio Prefixes (World) marl 66p Radio Valve á Semiconductor Data . £3.00 UHF repeater planning map . 40p UK Beacon List . . . 19p UK Repeater List . . 19p I ARU Region 1 Beacon List . 19p MORSE INSTRUCTION AIDS G3HSC Rhythm Method of Morse Tuition- Members' sundries Complete Course (two 3-speed 1p records and one ep Callsign lapel badge (5 weeks' delivery) . • - £1.31 record plus books) ...... £5.60+ Lapel badge (RSGB or RAEN emblem, pin fitting) 51p Beginner's Course (one 3-speed 1p record and one ep Tie (Maroon or Blue) . . . . . • £1.96 record plus book) . . . . . • £4.12+ Radio Communication Easi-binder . . . . £3.00 Beginner's 1p (0-15 wpm) plus book . . . . £3.44 4 Car window sticker (RAEN) (self-adhesive) 31p Advanced 1p (9-42 wpm) plus book . . . . £3.44t Members' headed notepaper (Out of stock) Three-speed simulated PO test 7in ds ep record . . £1.15+ Radio Communication back issues (as available) . 84p + Overseas orders: add £1.12. RSGB contest log sheets (100) . . . 77p RSGB teeshirt (large, medium or small) . £2.25 MAGAZINE SUBSCRIPTIONS Prices include postage, packing, and VAT where applicable. For QST (including ARRL membership) (Per annum) . £10.50 air mail despatch, please ask for price before ordering. Goods are CQ (Per annum) ...... £6.89 obtainable, less p ei‘ p, at RSGB headquarters between 9.30am 73 (Per annum) ...... £6.60 and 5pm. Monday to Friday. Subscriptions for the magazines listed above should be sent to RSGB, 35 Doughty Street, London WC1N 2AE. POSTAL TERMS: Cash with order. Stamps and book tokens cannot be accepted. Cheques and postal orders should be crossed and made payable to "Radio Society of Great Britain". Ham Radio (Per annum) (Includes air delivery) . £9.25 Giro A 'C No 533 5256. Ham Radio Horizons . . . . . £6.50 All overseas orders: add £1 to cover insurance if required. Subscriptions and changes of address for Ham Radio 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. OR DER FRO M:

RSGB Publications (Sales), 35 Doughty Street, London WC1N 2AE iv RADIO COMMUNICATION Septe mber 1977 A. J. H. ELECTR ONICS

Proprietor: A. J. HIB BE R D (G8AQ N) Tel: RU G B Y daytime 76473, evening 71066

T er ms of Business Cash with order, Mail order only, or Callers by appointment. S.A.E. with enquiries

Handling Charge 40p Minimum order £1.00. Offtclal order. accepted on • strict monthly beats Prices now include VAT FULL MONEY -BACK GUARANTEE ON ALL ITEMS

W15U V UHF WESTMINSTERS smote channel ;* characters, envelope size only 7/11* - 716* new and ITT 024CC ±6kHz ify 3db imp. 910 ohm complete with control box, cable C. cradle but LESS unused with data sheet 80p each. five for £2.50. ten for £4.00. speaker, mie. & power lead. all tested before 'clesplach £4.50. ITT 0240C ±3.75kHz 4 3db Imp, SIS ohm supplied with circuit & crystal into, alt sots in good HC6A1 CATHODEON Crystal Ovens MC0-2M 450, £6.00. condition "this is your chance to explote 70ems." 10,000nifd 16V electrolytic 351.- IT 024DEs923L ±3.51iHz /3. 3db imp. 820 ohm ONLY £35.00. P. P. £2.00. lOmfd 350V 10p. £6.00. PYE PFI UHF POCKETFONE TRANSMITTER SN7400 17p. ITT 04413A ±315kHz t 3db imp. 3-3k ohrr. UNITS no battenos in working order (used) Only SN7413 35p. /sm. £8.00. vesth cccuit-OK Moms SN7473 22p. rovocom TI4F02-M ±315kHz ft 3db Img. 010 ohm IT T AM7 STARPHONE P.C. BOARDS removed from SN7475 60p. £8.00. now & unused units: audio 6 squelch £5.00, AM IF SN7490 60p- 1-1MHz 1.58. SSO. FILTER made by Cathodeon Inc tot IF 10.7 MHz, 2nd IF 455 KHz with 2nd mixer &crystal, SN74121 380. PYE SSB125T Radiotelephone £4.00. filler r 3f KHz £9.00, AM modulator P. C. B. £6.00 SN47I41 801). ail above tillers are new 6 unused except for 445/LOU 3 ch. ese TX & Ru midis channel switch & knob "high SN74196 £1.40. 909B which is EX-EQUIP. band" & "mid band" mailable £2.00. Mod. )(former NE529K £1.45. ERNEST TURNER EDGEWISE METERS smell £2.00. MC10116 62p. precision typo 100 microamp FSD. marked 0-100 dispaly P. C. BOARDS for M5 UHF STARPHONE: single MC10131 £1.60. area 9/16' • 1I'. make nice "S" meter now boxed channel Tx 6 R. osc board £2.00. Tx multiplier P. C. B. 0A7805 5V regulator 103 case £1.50. £2.50. 420-440 MHz £7.00. PYE CAMBRIDGE 10.7MHz IF AMPS. new £3.00. JAPANESE TUNING METERS 1'sq. marked .. .TOM , SILVER ZINC BATTERY for UHF SFI STARPHONE PYE F27 T. PA TANK UNITS "P" band can be/Stored stereo" special °fie, 450 eaCh. we still Knee a law lilt £2.25. to 2 Mirs new 75p. SEMICONDUCTORS TANTALUM BEAD CAPACITORS 1m1 25v. 6.8rni PCB for breaking down contains 11 Plessey 5V reed HEWLET PACKARD HP5082-2800 hot carrier diodes 16v. 15rni 16v, 15rof 35v. 22m1 16v, 47m1.6v, 152nd 60. all relays 2 polo makesbreak, 11 BC107 transistor., 6 IC. 70p each 10p each. 74 series, 11 diodes A resistors ex-new equipment HEWLET PACKARD HP5082-3080 pin diodes 50p each DISC CERAMIC CAPACITORS 50vw 220-2.20001 in bargain £3.00. 4 for £1.75. MIXED BAG OF CAPACITORS polyester type 2547,' 612 series 3p each. VARICUP DIODES BB105 in matched sets of 4. 90p oar CARBON FILM RESISTORS 1, (,; wait 22 ohm-1 400vw. PC mounting sold by weight but a bag contains sel BA111 15p each. meocihrn ire El2 semis, minimum quantity or 10 Per approx 400. values •01.1m1d. 95% good. 1 lb bag £1.30 value suppliell•price 6 wall 130 per 10. ; watt 16P .i 70p post. VHF PO WER TRANSISTOR SRF1117 (Motorola) capstan type. 13e. 300 mlw input Doyen wens:wipe) on per 10. TRIM MER CAPACITORS: 145MHz FM (2( walls max output) special oiler 65P SG BRO WN MIC INSERTS same as u.ed in PYE mico. CERAMIC 10min dia 6inm high .2-801 3•10171, 4•20p1 6 each any quantity. but 300 ohm imp. OK Ica liner Iwo etc. £1.00 each hew 10.40pf. all Sp each. 7mm dia. 3.9p1, & 7.35018p each. only). TUBULAR CERAMIC solder in type 1-691.11p each 70p BF180 VHF•UHF RF amp. 20p each. 640 RECEIVERS. good condition, £45.00. six- for ten. 13F184 VHF RF amp. 1Sp each (replacement tor %vivo., 30.5MHz. 5 bands, slat calibrator etc. Buyer to collect CERAMIC MINIATURE COMPRESSION TYPE Westminster 'rent end.) by arrangement. 8 • 13inm P.C. mount 10.40pf 60 each. EIFY90 VHF RF amp 90p each. 641 RECEIVERS. 1514Hz-7301(Hz. £35.00. CERAMIC COMPRESSION 10-25001 10p each. (for ST2110 RF amp FT950MHz OK VHF To driver 15p each. P YE PF1 COMPACT *casing on RB6 (UHF) built in 70MH: It Feb R C.) PLASTIC SEMLAIRSAPCED 7mrn dla. CAU SE 16 pin OIL, FM IF amp. "S" meter. ABC. AFC tone burs) complete will, ballerieS and new leather Outputs OK for IF amo tor 2 MT, Ro with data sht el case. £60.00. 1-1601 PC mount 8p each. lOmm dia. 2-250,6p each ten £2.00. 24hr DIGITAL CLOCK with ;in dsiellai. elarm + 10 min for 50p, 2420 6 5-60.111p each. all 3 pin PC mount TBA6411/Al2 AUDIO AMP IC. gives 2 watts into 4 ohms snooze time, AMSPM indicator. site only 531n • 2mn OXLEY AIR SPACED sq base 1-10.1. 1-15.1. 180 with 9 volt supply, with data sheet £1.23, • 3(15 deep, guaranteed by us lor 12 menlhs, available each ten for £1.40. 2-30.1 20p each. in the fotio•vino cate colours-black, red, while, brown TETFER TRIMMERS Jack.on C16 Cat. No 5540 2.1001, 741 OP AMPS 8 pin OIL 35p each. and green. Please stale second choice, brand new sq. base, temp. coed, loss than 100opnv`C 400 each NESSS TIMERS OK for tone burst etc. 8 pin OIL. 45p. unused £14.00 each, an ideal clock lor the shack ten for £3.50. also 8mm dia. PC mount Cat No 5750 INTEGRATOR UNITS for PYE PFI PocketIona recely• STEREO CAR CASSETTE PLAYER AUDIO mien & into, as 5640. erg new OAS each. AMPS contains two NEC v4PC1001H2 audio ICs plus ERIE TEFLON TRIMMERS "530 $eries" S WITCHES M yer. I' die. • 7;16' long solder in type P.T.F.E 30 capacitors. 30 resistors, 4 transistors, on PC board, MINIATURE ROTARY SWITCHES I* die. 3 polo 11 insulason 100 each 4)' • If,' apples 3; watts RUS per channel ox 12VDC way make bolo,. break new 50p. 3 pole 3 way -r (os JACKSON BUTTERFLY TRIM MERS 17 17n1 supply. These have bean removed hom now units by the position) & earthing ring) break bolero make, 20p each. manufacturer and are not faulty in any way. Price £2.00 ()sow air gap Cal. No, C7I3 screwdriver aJeuStment SUB MINIATURE 7 pole 10 way (remove the slop & It each or two for £3.50. you could not buy the capacitors 509 each. few with spindle 65p each. for this price' With circuit. PLASTIC SEM1-AIRSPACED TRIMMERS 10-60plas make, 2P 12 way) 5'32' spindle Sep each. SLIDE SWITCHES 2p CO std size three for 17p. CAR RADIO PCBs, Famous British manulacturors used in PYE WESTMINSTER PA units 15p each. VIDEO CAMERA SCAN & FOCUS COIL ASS. rejects due to P.C. track defechi"soldlor components" REVCO ; wave mobile aerials for 145MHz £7.00 + 60p but can be used or a number of projects Inc. top band transistor 17rzo to suit std. 1' vidicon tubo Inc. centring post. High bond 156-174MHz some price. magnets 6 tube clamp. no info, new unused £8.00 each OF net. Tho IF and audio stages tiro complete, the FERRITE RINGS 9116' die, no gen. 10p also a lew I' mixer stage is wired but was originally designed for a Iwo lot £11.00. die with O turns wire Removable) 3p each. PLUGS•SOCKETS permeability tuner. new and unused. only £1.60 inc. FERRITE BEADS similar to FX1115 Olor 10p. circuit. Circe.' only-8(p stamp 5.A E. 50 ohm BNC Plugs 50p. 50 ohm BNC right angle adaptors 600. 50 ohm BNC single hole sockets 50p. 50 ohm BNC 10-7MHz 1FTs. single tuned transistor type I* Sri 10P. FM RADIO FRONT END TUNER UNITS 88-108MHZ single hole sockets cable entry type SOp each, PL259 455-470k Hz IFTs. single tuned transistor type 1" sq. 10p. 107M44; I.F. output A filled with A.M. gang, plugs P.T.F.E. Ins. 509. 50239 sOckels P.T.F.E. Ins. ELECTRONIQUES TUNING DIALS £5.00. capacitor, FET RF amp, non mixer, separate ose. AFC 50p. & ABC Monts, geared tuning brand new with circuit CRYSTAL HOLDERS HC6•U usable P.C. or chassis SPECIAL OFFER: 50 ohm "N" plugs lor UR43 co-ax requires 9•12V DC. BARGAIN ONLY £3.30 each. mount, HC25 ,U, HC25sU P.C. mount FT243, chassis 35p. 75 ohm BNC plugs 30p. 75 ohm BNC single hole nmunt all tip each. ITEMS FOR FREQUENCY COUNTER FEATURED sockets 300. each. COILS 5mm die, lOmm sq. base tor P.C. mounting com- IN MARCH 1976 R.C.: 10 7MHz CRYSTAL FILTERS: plete with core as used in PYE raJ101010phOnot Sp MAINS TRANSFORMER 240-250V input-output 250V STC 445 LQU'929 e 15014 3411) Imp. 910 ohm (for each v.53 nt•A 6.3V IA, uni 9V 'ru 1A. We had this item PYE Pocketiono PF1) £3.00. COILS ;"sq.. CANS;" high 5p each. specially made £6.00. TOYOCOM 10M•513-1 z 7.5kHz 5db imp. 31.. Ohm I.C. SOCKETS 8 pin 10p, t4 pro 15p, 16 pin 16p OaCh. DECADE COUNTER PCB. Made to suit our miniature £3.50. (law profile) ITT Nixie subosiITT5353S) suitable lor use with 18 way STC 4451.0U/901A ,..-.15kHz .6, 3db imp. 2k ohm 01* pitch edge connector if required, ready drilled and £2.50. REED RELAYS 14 pin OIL made by ASTRALUX Sipe tinned to take SIV7490, 7475 and 74141 75p each set of SIC 44510Ut901N 101414 a, 1.5db imp. 2.61‘ Ohm 121A-3, 5 volt coil 500 ohms TTL compatible. with rive £3.40. I* pitch edge connector to full above PCB. £4.00. normally open contacts. new 45p each ten 101 £3.50. 643p STC 445 LOU 9090 • 7•5kfiz •• 3db imp. 910 Ohrn as 3 GANG TUNING CAPACITOR 3650 per section MINIATURE NIXIE TUBES 1TT-5853S to null the used PYE FM Weshmnsters direct drive 75p each. above decade boards tell and right decimal points, EX-EQUIP. £2.50. SOLDER.IN INSULATORS repro. nia 10 0 in, 501s. 59 W AVERLEY ROA D, THE KE NT, RU GBY, W AR WIC KS HIRE

Printed in Great Britain for the RA DIO SOCIETY OF GREAT BRITAIN, 35 Doughty Strict, London, WCI N 2AE by The Garden Cris Press Limited, Letclmortli, I tertfordshire SG6 lis