RadCom December 2012, Vol. 88, No. 12

| November 23, 2012

Cover of RadCom for December 2012RadCom is the Radio Society of Great Britain Members’ magazine and is sent free every month to Members of the Radio Society of Great Britain.

RadCom has the largest amateur radio readership in the UK and is respected throughout the world.

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Contents RadCom December 2012

Members log-in is required to read the magazine online

News and Reports

  • 7 RSGB Matters
    Including Contacts, Society matters, National Club of the Year, QSL matters, New Members and Congratulations
  • 10 News
    News from the world of amateur radio
  • 12 RSGB Centenary Year Events
    John Gould, G3WKL takes a look at some of the events planned for the RSGB Centenary Year
  • 68 2012 Index
  • 80 Around Your Region


  • 16 ACOM 1500 linear amplifier
    At 400W this amplifier is very docile and should give a long life, writes Peter Hart, G3SJX
  • 38 Book Review
    Giles Read, G1MFG looks at a bumper selection ranging from the ARRL Handbook to MI5 secrets
  • 52 TYT TH-UVF9
    A dual band handheld that’s a very attractive proposition, says Giles Read, G1MFG

Technical Features

  • 19 Homebrew
    Eamon Skelton, EI9GQ uses parts of an old electric fire element to build a stable VFO for the direct conversion receiver project
  • 27 Start Here
    More on the Tesla Coil project by John Welsh, G0NVZ
  • 28 EMC
    Dr David Lauder, G0SNO looks at interference issues from ADSL plus news on using loop antennas for HF measurements
  • 34 Design Notes
    Subharmonic mixers, paralleling MMICs and remote ATU tuning are just some of the subjects covered by Andy Talbot, G4JNT
  • 36 Data
    Dial frequency, mark frequency, space frequency -what frequency are you actually on? asks Andy Talbot, G4JNT
  • 42 Noise power testing of HF receivers
    Adam Farson, VA7OJ/AB4OJ explains how to use notched noise spectra to evaluate receiver performance
  • 57 Adapting the Heil Pro Set Elite iC
    How David Barber, G8OQW made his headset work with a Kenwood TS-2000


  • 24 2012L
    Amateur radio celebrating the London 2012 Olympic and Paralympic Games, described by Dave Lawley, G4BUO and Bob Treacher, M0MCV
  • 30 Expedition to Bressay Lighthouse and the Shetland Isles
    Dave Brooks, G4AIR reports on an intrepid group from Grantham who activated sites for ILLW, WAB, WFF and SOTA
  • 41 Amateur Radio Observation Service
    Keith Bassett, G7NBU lifts the lid on the former ‘secret service of the RSGB’


  • 91 Advertisers index
  • 54 Antennas, Peter Dodd, G3LDO
  • 66 GHz, Sam Jewell, G4DDK
  • 60 HF, Don Field, G3XTT
  • 46 IOTA , Martin Atherton, G3ZAY
  • 58 LF, Dave Pick, G3YXM
  • 75 Propagation, Gwyn Williams, G4KFH
  • 53 QRP, Rev George Dobbs, G3RJV
  • 87 Members’ Ads, Rallies and Events, Silent Keys, and Special Event stations
  • 72 Sport Radio, Steve White, G3ZVW
  • 92 The Last Word
  • 62 VHF/UHF, Sam Jewell, G4DDK


We wish to apologise unreservedly to Mrs C Parker, M3TBP.
Her details inadvertently appeared in the December 2012 Silent Keys list, rather than those of her late husband, Mr R Parker, G4KAK.
We deeply regret any distress that has been caused.

Information for RadCom readers


© 2012 Radio Society of Great Britain. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior written permission of the Radio Society of Great Britain.

Errors and Omissions

Whilst the Radio Society of Great Britain—the publisher—takes all reasonable care in the production of RadCom, we can accept no responsibility for errors, inaccuracies or omissions contained within the magazine or any subsequent loss arising from any use thereof. Reliance placed on the contents of RadCom is at the reader’s own risk. We urge any reader to take all precautions appropriate to avoid any loss or damage to equipment and ensure the personal safety of themselves and others when using material contained in RadCom. It should be also noted that patent or copyright protection may exist in relation to any items within this magazine. The RSGB does not accept any responsibility for failing to identify any such patents, copyright or any other protection.

Readers are also reminded that the use of radio transmission and reception equipment—including scanning—is subject to licensing and the erection of external aerials may be subject to local authority planning regulations.


Although RSGB staff and the staff of Danby Advertising—its Advertising Agent—take reasonable precautions to protect the interests of readers by ensuring as far as practicable that advertisements in the pages of RadCom are bona fide, the magazine and its publisher, the RSGB, cannot accept any undertaking in respect of claims made by advertisers, whether these advertisements are printed as part of the magazine, or are in the form of inserts. Under no circumstances will the magazine accept liability for non-receipt of goods ordered, late delivery, or faults in manufacture. Legal remedies are available in respect of some of these circumstances, and readers who have complaints should address them to the advertiser or should consult a local Trading Standards Office, a Citizens’ Advice Bureau, or their own solicitors. The publishers make no representation, express or implied, that equipment advertised conforms with any legal requirements of the Electromagnetic Compatibility Regulations 1992. Readers should note that prices advertised may not be accurate due to currency exchange rate fluctuatons, or tax changes.

Category: RadCom