Ken Taylor, M1SLH, on FT-8 digital mode, 21 November 2017

On 21 November 2017, Ken Taylor, M1SLH, gave a talk about FT-8 Digital Mode.

FT-8 digital mode
FT-8 digital mode

In July of this year a new digital mode was added to the well known WSJT suite of software for weak signal contacts. It is very sensitive and particularly fast, each exchange taking less than 15 seconds, and has become extremely popular.

Using forward error correction, advanced signal processing techniques and a very narrow bandwidth it had proved an easy and reliable way of making DX contacts on HF under less than favourable conditions as we slide down the sunspot cycle.

This talk centres on setting up and operating using FT8, without delving too much into the technicalities of how it does it. It is also planned to give a live demonstration. As several members have already been using the mode for a while, there will, no doubt, be an exchange of tips and tricks afterwards.

John Graham “Surplus Test Equipment” talk, 7 November 2017

On Tuesday 7 November 2017, John Graham delivered his exceptionally learned talk on Surplus Test Equipment for the Amateur Laboratory.  Below are a list of relevant links:

Yahoo groups:

http://groups.yahoo.com/group/hp_agilent_equipment

http://groups.yahoo.com/group/marconi_test_instruments

http://groups.yahoo.com/group/Rohde_Schwarz

http://groups.yahoo.com/group/WG-Fans

http://groups.yahoo.com/group/siemens_messtechnik

Sources of pdf manuals

http://www.ko4bb.com/getsimple/index.php?id=manuals

http://www.electronicsandbooks.com/eab2/manual/index.php?dir=Hardware%2F

http://www.ebaman.com/index.php/remository/ELECTRONICS/Test-Equipment/

http://www.keysight.com/main/facet.jspx?t=79841.g.1&cc=GB&lc=eng&sm=g

http://w140.com/tekwiki/wiki/Main_Page

http://docmesure.free.fr/telecharger.php?dir=Tektronix/Serie%207000/

http://www.hakanh.com/dl/kits.htm

https://sites.google.com/site/marconiinstrumentslimited/home

http://www.radioscanner.ru/files/rohde-schwarz/

PDFs for sale: Artek, Mauritron, etc

Other links

https://vk8bn.me/info/measuring-complex-impedances-using-thehp8405a-vector-voltmeter/

Farson, AB4OJ: Noise Power Ratio (NPR) Testing of HF Receivers:  www.ab4oj.com/test/docs/npr_test.pdf

Verbana, I2VGO: Measurement of all products intermodulation on HF receivers: www.ab4oj.com/test/docs/test_npr.pdf

KE5FX GPIB Toolkit: http://www.ke5fx.com/gpib/readme.htm

The Gliwice Radio Tower by Phil Miller Tate M1GWZ, 19 September 2017

Gliwice Radio Tower
Image available by Andrzej Jarczewski at Polish Wikipedia

There were nine members present, one visitor who later joined, and our guest speaker Phil Miller Tate M1GWZ from Walton on Thames. Several apologies for absence were received.

Phil’s topic was the Gliwice radio station, now in Poland. Originally constructed as a medium wave broadcast station in the 1930’s, it is famous for it’s wooden tower, tallest in the world, probably, and
a botched attack on it by the German SS pretending to be Polish insurgents, giving Hitler an excuse for invading in 1939. It was a thoroughly interesting talk and delivered in an entertaining manner.

Today the station is a museum, and the larch wood tower still survives, held together with brass bolts replacing the original stone hardware. The tower now supports mobile phone antennae, and a low power FM station on 93.4MHz, for any FMDX fans.

We also welcomed James, M0JHF (also K0FOZ) from Cumnor, who has joined ODARS.

The next club meeting will be on Tuesday 3rd October.

ODARS Field Day, 2-3 September 2017

By Chris G7IVF

Many thanks to all those who helped make last weekend’s VHF contest 
event possible. I have submitted the log and for those who are 
interested, here is a link to a map of the contacts we made: http://www.rsgbcc.org/cgi-bin/vhfresults.pl?kml=/2017/wyfWgIfHOx4MEm34JqFCwnDIcyYwu24

The bulk of the interesting DX was obtained on Sunday morning, which was a pity, because just as it was starting to get interesting, the weather 
came and chased us away!

The list of claimed scores for comparison is at http://www.rsgbcc.org/cgi-bin/claim.pl?Contest=144MHz%20Trophy&year=2017

Demonstration of making contacts from the club meeting, 5 September 2017

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There were seven members present at the meeting on Tuesday 5 September 2017, plus an unexpected but very interesting guest.

After a bit of general discussion, Chris G7IVF gave us a report on the weekend activities in the 2m Trophy Contest. The set-up went well using a guyed 11m mast made of scaffolding pole sections for easy transport. This was mounted at the bottom on G4AZN’s rotator, supported by bearings made by Ted G3LPU, and using a new clamp specially purchased for this type of activity. The 2m aerial was Colin M0DDT’s 16 element yagi. This was attached to the K3 transceiver and Elecraft 2m transverter with LMR400 cable and powered from the club generator. However, on Sunday morning the weather worsened and with the prospect of rain, it was decided to abandon the attempt.

Our guest was Jim 7J1AJH. Originally from the USA he now lives in Tokyo Japan and is in Oxford attending a software conference, so looked us up and dropped in. Jim gave us some interesting insights into ham radio operating in Japan.

For the first time, I think, we then set up a live station and made some QSO’s from the hall! Chris brought in his portable apparatus he normally uses for 2m activity contests and was originally planning to set up in the garden outside. However, once again the rain came down so he set up inside to see what would happen. The equipment was the Yaesu FT-857D running 25w battery powered to a portable 5 element yagi which could be broken down for easy transportation. As the evening coincided with the 2m activity night a few local stations were heard at good strength. Chris then tried calling some of them and made 3 or 4 QSOs. To support the antenna, one or two members initially held it aloft, but it was eventually connected to a fibreglass pole, supported valiantly by Jim, our guest.

Marconi and history of wireless talk at ODARS by Liz Bruton, May 2017

Liz Bruton before her talk
Liz Bruton before her talk

13 Members and 1 guest were present to hear a fascinating talk by Liz Bruton on Marconi and the 1898 Kingstown (Dun Laoghaire) Regatta.

Marconi, ever eager for publicity, readily accepted the invitation of the Dublin Evening Mail to report by wireless the progress of the races. Liz described some of the details of the extensive preparations and the equipment used. During the three-days of the regatta, over 700 reports were sent by wireless from the Flying Huntress to the Evening Mail and its sister paper The Dublin Daily Express. The operation was an outstanding success and secured great publicity for Marconi and his wireless system.

ODARS teaches Morse Code for Marconi Day 2017 at the Museum of the History of Science

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Once again ODARS members set up a special event station at the Museum of the History of Science to celebrate the birthday of Guglielmo Marconi. It is quite a challenge to do this as the museum is in a listed 17th century building in the centre of the City of Oxford and we are no longer allowed to use the roof for antennas. So we used 3 fibreglass poles attached to the railings supporting an off-centre fed dipole for 40 and 20metres. However, our location in the basement was adjacent to the cabinets containing some of the historic Marconi collection, so we were well placed inside.

Conditions were difficult – as well as the usual high noise level the K index was also high but although propagation was poor some contacts were made around Europe and into Asiatic Russia. As well as the GB4MHS station, we ran a very popular Morse code hands-on experience, and Brian G2KQ’s excellent demonstration of early wireless equipment.

Many visitors dropped by and talked to us and seemed interested in what we were doing. We hope that some of them may develop an interest in amateur radio.

World War Two marine radio operator and RSS voluntary interceptor speaks at ODARS, April 2017

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Update, July 2017: We are sad to announce that Peter Stewart is now a Silent Key.

17 members and 10 guests met at the Gladiator club on Tuesday 18th April to hear a fascinating talk from Peter Stewart about his early career as a wireless operator in the merchant navy and the wartime Radio Security Service (RSS) during World War Two and post-war career in the Diplomatic Wireless Service.  We were privileged to hear a talk from one of the few remaining Volunteer Interceptors and RSS operators from World War Two.

Highlights of his talk included it being decided by his family, without any input from him, that at the age of 16 he should be sent to sea as a deckhand, his progress to wireless officer, having an appendectomy after swinging the lead in order to avoid a posting, being enrolled in the RSS and subsequently the Army and the boredom of sending and receiving 5 character code groups all day.

Peter is now 91 and in the days after his talk he let it be known that earlier in April he had been fitted with a pacemaker which due to complications required two hospital stays. We are very grateful to him for making the special effort to come and talk to us.