Radio Communication October 1989 ELECTRONIC COUNTER MEASURES: How a moth, a 40 year-old aircraft and the RAF join forces to cause confusion IMF ----- LEICESTER SHOW PREVIEW KEN WOOD TS-950S. This is DX-clusive Rumours have abounded for some months that from your operating frequency — even during Kenwood were once again about to take the HF transmitting; such as the revolutionary digital signal transceiver market by the throat, and with the processing option which gives improvements of up to announcement of the TS-950S those predictions have 10 dB in carrier and unwanted sideband suppression; proved to be true. It is an undisputed fact that variable transmit bandwidth; adjustable rise time of Kenwood HF transceivers have always led the way, the CW envelope; and much more. and it seemed almost impossible for their design team The photograph and this brief text can only give a hint to make significant advances on the success of the TS- of what the TS-950S can deliver — the full story can 940S, — but they have. only be told by a visit to your Kenwood approved We don't have to tell you that the receiver performance dealer or a browse through some detailed literature, is outstanding; a noise floor of -140 dBm will do that. but take it from me that once again, Kenwood have Nor do we have to mention the ease of use; Kenwood shown the way forward in HF transceiver design. has an enviable reputation in this area. What we must give a few hints about are some of the new operating John Wilson G3PCY/5N2AAC aids which Kenwood have included, such as a dual receiver which allows you to listen up to 500 kHz away LOWE ELECTRONICS LTD. Chesterfield Road, Matlock, Derbyshire DE4 5LE Telephone 0629 580800 (4 lines) Sole Appointed UK Distributor for KENWOOD Amateur Radio Editor Trevor Preece, G3TRP Deputy Editor David Bobbett, 041110 News Editor (Acting) Radio Communication John Nelson GW4FRX Design V OL U M E 65 No 10 O C T O B E R 1989 Linda Penny Draughtsman Derek Cole CONTENTS Editorial Assistant Giles Booth Editorial Secretary Marcia Bnmson 4 SO CIETY AFFAIRS News from HFCC. EMC News, Raynet Zone 2 Result An contributions and correspondence Radio Communication concerning the content of Radio 6 NE WS Communication should be posted to: Flying Dutchmen. 144MHz on Ben Nevis. Ohm's Law?, Lake District The Editor LX MOKit OVNTU YEAStqlerc Rescue, News from Waterloo Bridge House, WARC in 1992, WAB News, RaJlo Communication GB2ATC. New Products, New VHF Records, Sussex Fair. American Lambda House, Cranborne Road Licences, Famous Callsign Re-issued Potters Bar, Hens EN6 3J E Tel (Editorial): 0707 59015 fia/r 4 +4 14 ELECTR ONIC CO U NTER MEAS URES Fax (Editorial): 0707 46094 How to go jam ming ... and get paid for it Tel (GB2RS late changes): 0707 59260 17 SPECTR U M AN ALYSIS E-mail (Telecom Gold): 76:MSX020 eHF Prestel Page 8107 eHF Propagation Predictions •VHF/UHF Fteports for Spectrum Analysis should ¡FUR," • •SWL be sent to the Band Editors: r eS111, HF John Alfaway. G3FKM, 10 Knightiow 34 TEC H NIC AL TOPICS Road, Birmingham B17 8013 PSU Compromises • Microwave Oven TV • Dual-Voltage and VHF/UHF Main Photo: Canberra Ti? used by RAF 360 Squadron for Electronic Voltage-Multiplier PSUs • HF Packet • Battery Charger Controllers • Norman Frtch.G3FPK. 40 Eskdale Aircraft-Enhanced Propagation Gardens. Purley. Surrey CR2 1EZ Counter Measures — page 14. (Telecom Gold 76:MSX022) Inset: Dutch amateurs and kite experts — page 7. Telex: 9312132268 (SAG) 40 S WIT C HE D MO DE POWER SUPPLIES SWL We demystify the SMPS Bob Treacher, 93 Elibank Road. Ettham, London SE9 10.1 44 BEAN TIN ANTE N N A MICROWAVES Mike Dixon. 63PFR, Woodstock, How to re-cycle rubbish and get a 15m antenna Gazebank. Honey. Warrington, Cheshire WA6 BLL 46 RS GB MAIL OR DER PUBLIC ATIO NS ADVERTISING All display and classified 47 SIMPLE 20m BEA M ANTE N N A advertising enquiries (excepting An effective and inexpensive 3-element 20m beam for beginners and Members' Ads) should be experts alike directed to our advertisement agents Victor Brand Associates Ltd. 49 LEICESTER SHO W PREVIE W 'West Barn', Low Common, eA sneak preview of some of the goodies on show Bunwell, •Pull-out floor plan and fist of exhibitors Norwich, Norfolk NR16 1SY, Tel: 095 389 8473 G1AD W and G4LXM handing a 55 IN PRA CTICE Fax: 095 389 8437 cheque for £927 to Nikki Browne — page 9. Reforming Electrolytics e Safe Operating Area • Mains-borne Noise • Hi -Fi RFI • Get the FT101 on the New Bands • Heatsinks Radio Communication is published by the Radio Society of Great 60 C OL U M NS Britain as its official journal on the •DATACO M MS Getting Started, Future TNC Firmware last Friday of the previous month and is sent free and post paid to all *MICR O WAVES Awards, Eastnet's Experiences members of the Society. •ORP ...goes to Texas •SWL 6th HF Challenge. HAB Awards Closing date for contnbutions. unless eEMC MATTERS Screened Enclosures. Euro Meeting otherwise notified, is five weeks prior to publication date 78 C O NTEST NE WS AND RESULTS Cd,', Radio Society of Great Britain 1989 83 CLU B FILES The first part of our comprehensive list of affiliated clubs and societies, ISSN 0033-7803 from Avon to Hampshire. 95 ME MBERS' ADS Filmset by JJ Typographies Ltd. Collis I louse. Locks Hill, Rochford. 98 HELPLINES Essex ssa IBX 98 DIARIES AN D DATES Printed by Mayhew McCrimmon Printers Ltd. Uni s -4 Star Lane Club News, Mobile Rallies, GB Calls ndustrial Estate Great Wakering. Essex. SS3 OPJ. 100 THE LAST WOR D 102 ADVE RTISERS INDEX n a7ll r Mi 36,070 copies per Switched Mode Power Supplies ...mepageo. tu 40 Loar Issue average explained — mowi, o. clam ance.s circulation in 1987 RADIO COM MUNICATION October 1989 3 Manual revisions, RSGB COUNCIL representation at the IARU Region II 1989 Conference and the RADIO SOCIETY OF ARRL 75th Anniversary BRIEF celebrations, EMC and DiY-Radio. GREAT BRITAIN 30 March 1989 Council Meeting News from THE NATIONAL SOCIETY WHICH REPRESENTS UK RADIO AMATEURS M1The policy of Council to move Founded 1913. Incorporated 1926. Limited by guarantee. the Society's Annual Meeting to the HF Member society of the International Amateur Radio Union different parts of the UK, to give contest more members an opportunity to PATRON: HRH PRINCE PHILIP, DUKE OF EDINBURGH. KG attend the Annual Meeting, was com mittee discussed at length. Membership is open to all those with an active interest in radio experimentation AFS AND CUMULATIVE A decision on the location of the and communication as a hobby Applications for membership should be made RESU LTS 1989 Meeting would be made at to the secretary. from whom full details of Society services may also be For the members who enquired obtained. the next meeting of Council. about the late publication of these MA new Chairman for the VHF results, the AFS Results appeared Headquarters arid registered office: Contests Committee, Bryn in the September 1989 issue of Lambda House, Cranbome Road, Potters Bar, Herts EN6 3JE Llewellyn, G4DEZ, was appointed RadCom. and the LF Cumulatives Telex 9312 130923 (RSGB) Electronic mail via Dialcom/Telecom Gold: 87:C00083 following the resignation of John appear in this issue. Telephone: 0707 59015. Fax: 0707 45105 Quarmby, G3XDY. Council thanked G3XDY for his great CONTEST LOG AND Secretary and Chief Executive: David Evans, G3OUF contribution to the work of the DECLARATION SHEETS Society, A number of clubs have asked if there is any objection to them aProdcedures were agreed COUNCIL OF THE SOCIETY using photo-copies of the RSGB whereby the Society would be PRESIDENT: J Gannaway, G3YGF contest stationery, as they often represented at Rallies by locally EXECUTIVE VICE-PRESIDENT: FO Hall, Gm8Bzx need extra copies for NFD and based officers of the Society. IMMEDIATE PAST-PRESIDENT: SSS FD etc. The HFCC will Sir Richard Davies. KCVO, CBE. CEng. FIEE, G2XM IMThe Tartan, Scottish and always accept photo-copies HONORARY TREASURER: POSITION VACANT Founders Trophies were discussed. provided they are A4 size. The samples in the RSGB Callbook are ORDINARY MEMBERS OF COUNCIL leouncil discussed the Editor-in- undersized, but as the reduction E J Allaway. MB. ChB, MRCS, LRCP. G3FKM Chiefs letter to Mr Willis, G8VR, applied to both width and length, N G Brinkworth, G3UFB in which he had asked Mr Willis to Mrs M H Claytonsmilh, G4JKS a small amount of enlargement stand down as the contributor of G R Jessop. CEng, MIEE. G6JP during the copy process brings the VHF bands column. Mr Willis A McKenzie. MBE, CEng, FIEE. FAES, G3OSS them up to A4 size. Computer- F S G Rose, G2DRT attended the meeting of Council to derived logs may also be used for G L Benbow, Msc. CEng, MIEE. G3HB put forward his views. After much all RSGB 11F contests, but again discussion, Council thanked Mr they must be formatted to the ZONAL MEMBERS OF COUNCIL Willis for his attendance and standard contest log sheet (40 Zone A G R Smith, BSc, MISTC. MBIM. G4AJJ agieed that in future columnists entries per page) and use the Al Zone B J Allen. G3DOT would be appointed annually by paper size. There is no restriction Zone C J Greenwell, AMIEE. G3AEZ the Editor in association with the on the paper size for the Zone D P E Chadwick. G3RZP Technical and Publications Zone E E J Case. GW4H WR declaration (cover) sheets. There Advisory Committee. Zone F J T Barnes, GI3USS have been enquiries as to why the Zone G F Hall, GM8BZX standard log sheet is not 1111The terms of reference for the formatted to line-printer or daisy- Finance and Staff Committee were HONORARY OFFICERS wheel standards.