Promoting and Supporting Amateur Radio since 1961
THE CATSWHISKER – NOVEMBER 2010
Keeping members and
friends informed about
SDRS events and news
since March 1967
The next meeting is on Tuesday November the 9th
THE WEYMOUTH H STATION UPDATE Following the recent articles in Catswhisker about the WW2 BBC 'H' stations, Mike Box, G3RZG who used to work for the Post Office, recalled the Weymouth station being checked and inspected annually for quite a long time after the War. It was part of a Civil Defence radio network during the Cold War, presumably discontinued once conditions in Eastern Europe became favourable, though exactly when is in some doubt but it was probably well before the demise of Communism. (The Berlin Wall fell in 1989.) This confirms information that I had from two other sources, but Mike added that the station was fed by land line from Eggardon Hill. John, M0BMQ
2011 RSGB YEARBOOK REMINDER Don't forget that our Treasurer John, M0BQO has the latest (2011) RSGB Yearbook (SDRS being an affiliated club) and it is available for any member to borrow. It also contains a CD with various radio-based software etc.
OCTOBER MEETING ANTENNA ANALYSER DEMONSTRATION At the October meeting Rob, G0RYL gave us a most interesting demonstration of an Antenna Analysing package that used a very comprehensive computer programme and a mini Radio Solutions miniVNA analyser. This was connected to a SRC X80 multi-band HF vertical that was erected outside the building.
The miniRadioSolutions - HF VHF Antenna analyzer www.miniradiosolutions.com The miniVNA is a tiny antenna analyser working from 0.1 to 180MHz. It is connected to a computer with just one USB cable, power is supplied over USB. An internal option for serial (RS-232) communications is available as well. The miniVNA allows you to quickly analyze any antenna over a user defined frequency range between 0.1 and 180MHz. You see at a glance where the antenna is resonant, what the SWR is and what the return loss is. The best (minimal) SWR frequency is automatically found and displayed. Two markers can be freely placed within the shown frequency range and measure impedance [Z], resistance [R], phase [ω] and other values at these points. Other functions of the mniVNA allows you to measure cable losses, cable length, transmission, bandwidth and quality of filters etc. Software is available for Windows™ and Linux™ operating systems. During the demonstration Rob was using MiniVNA230 for Windows. Information on the SRC X80 antenna can be found here: www.snowdonia-radiocompany.co.uk/ourshop/prod_514853-SRC-X80.htm Many thanks to Rob and to his crew who helped set up the demonstration. Rob has kindly provided a couple of screen shots of the system in use and these are shown below.
SOUTH DORSET RADIO SOCIETY 2010/11 G3SDS G8SDS M2Z CONTACTS AND INFORMATION CHAIRMAN: Graham Webb, 2E1GOQ
[email protected] 01305837356 SECRETARY: Carol Hodges, 2E1RBH
[email protected] 01305820400 Marine Cottage, 1a Clements Lane, Chiswell, Portland, Dorset. DT5 1AS TREASURER: John Rose, M0BQO
[email protected] 01305832057 45 Ringstead Crescent, Weymouth, Dorset. DT3 6PT Arthur Werrett, M0VAW Fred Talmage, G0LVF Jamie Wrightson, 2E0WON Janet Dean, 2E1NRQ President: Geoff Watts, G0EVW Vice President: Robert Hodges, G0RYL SDRS Web Site: www.g3sds.org.uk Pictures here: www.sdrs.zoomshare.com SDRG (GB3SD/DR) Web Site: www.gb3sd.radiouk.com
WORDS OF WISDOM “Technology is dominated by two types of people: those who understand what they do not manage, and those who manage what they do not understand.”
THE CATSWHISKER Our Society’s Newsletter has been called 'The Catswhisker' since its inception. The word is defined thus in the Oxford Concise Dictionary. cat's whisker n. a fine adjustable wire in a crystal radio receiver. the cat's whiskers (or pyjamas) slang an excellent person or thing.
NEWSLETTER PRODUCTION Until a new editor/producer can be found, the SDRS Newsletter is being produced and edited by our President, Geoff Watts, G0EVW. Please send any material for inclusion in Catswhisker to Geoff using e-mail
[email protected]. Or by post to: 46 Links Road, Weymouth, Dorset DT4 0PE. You can also phone or send a text message to Geoff on 07502198447. Please note that news material needs to arrive at least 10 - 14 days before each meeting. © SDRS 2010
