Category Archives: Events

RSGB CommonWEALTH CONTEST

The RSGB Commonwealth Contest runs from 10:00 on Sat 9th March to 10:00 Sun 10th March. You will hear participants calling CQ BERU (British Empire Radio Union). This is a CW contest in which the participants must be in commonwealth countries such as Australia, New Zealand, Canada, Ghana, The Gambia, Grenada to name a few. A full list of Commonwealth Call Areas may be found at https://www.rsgbcc.org/hf/information/codes.shtml. Stations from those areas may also work Headquarter stations including those from their own call area. The contest details may be found at https://www.rsgbcc.org/hf/rules/2019/rberu.shtml.

Bob G3PJT maintains an interesting site at https://berucontest.wordpress.com/ with the latest news about participants, especially those travelling to some far-flung part of the commonwealth. Our own Don G3XTT will be operating as C56DF from The Gambia. I’m sure he would be delighted to work as many RADARC members as possible!

One of the advantages of this contest is that it is easier for UK stations to work DX because you are not competing with most of Europe or the USA. Saturday afternnoon is worth trying for African stations on 20m. You should also be able to work many Canadians on 20m from mid-afternoon to mid-evening, and on 40m during the evening. It’s worth getting up on Sunday morning to operate between about 06:00 and 07:30 as you’re likely to work VK and ZL on 40m and possibly 80m. There’s a very noticeable lift around UK sunrise that coincides with sunset in ZL.

RADARC in RSGB AFS contests

RADARC participated in three RSGB AFS contests in January – CW, Datamodes, and Phone. Each was of 4 hours duration on 40m and 80m. Typically stations started on 40m and as propagation changed, moved to 80m. In all three legs, it was very noticeable that GM stations had much better conditions on 40m than the Gs, and hence GM stations tended to be the winners or runners-up.

AFS CW
RADARC came 6th in the Local Club category with a team consisting of Don G3XTT, David M0DHO, Jim G0LHZ, and Michael M0MPM. I stayed on 40m longer than many, and this helped to reduce the time at the end of the contest whenI had worked everything on 80m. For details, see https://www.rsgbcc.org/cgi-bin/hfresults.pl?Contest=AFS%20Contest%20CW&year=2019.

AFS Data
RADARC came 24th in the Local Club category with a team consisting of David M0DHO, Michael M0MPM, and Simon M0ZSU. This was my first attempt at a datamodes contest and using N1MM and MMVARI to send RTTY and PSK, and I treated this as a learning exercise. For details, see https://www.rsgbcc.org/cgi-bin/hfresults.pl?Contest=AFS%20Contest%20DATA&year=2019.

AFS Phone
RADARC came 14th in the Local Club category with a team consisting of David M0DHO, Jim G0LHZ, Jonathan M0JSX, and Michael M0MPM. Dealing with the inevitable QRM is one of the challenges. Running with 400W meant that I was able to keep my run frequency on each band. For details, see https://www.rsgbcc.org/cgi-bin/hfresults.pl?Contest=AFS%20Contest%20PHONE&year=2019.

meeting 14th February – TELL US WHAT YOU’RE UP TO!

14th Feb Woodford Park meeting is a chance for us to catch up on the
various projects/activities we’re up to – in particular any follow ups
to the Great Construction Contest but not limited to that.

If you’d like a short (5 minute or so) slot let me know.

Doesn’t have to be stuff – could be contest updates or how RADARC
contributes comms to events like 3 towers etc.

Also – what would you like to see and I’ll try and arrange?

We can take contributions on the fly on the evening if need be.

  • Min G0JMS will kindly bring along a RigExpert HF to VHF SWR meter (Digital display) RigExpert to show you and VHF to UHF swr power meter (Cheap unit) which includes frequency. He will also do a brief demo of Yaesu Fusion – Wires X technology RF paths permitting.

If necessary, I’ll bore you for a few minutes before the bottles and
tomatoes start flying:

  • Geostationary satellite project – es hail 2. Mike G4CDF (and possibly others???) is making the running on this one but I will present on his behalf a very short overview. iirc it’s 2.4GHz up and 10GHz down. tx/rx is based on an SDR transceiver (lime sdr mini).
  • Adventures with FT8 internals and taxi radios (generating FT8 tones by pulling a carrier around) – update. TBH anything that generates a stable carrier and can be pulled a bit maybe down to 1Hz resolution looks like it might work – eg. voltage controlled oscillator.
  • cheap RTL-SDR dongles (£15 delivered). Mine does work but probably better to get the real ones rather than fakes like mine.
  • short gnuradio demo (maybe)

We’ll have the ICOM IC7300 out for people to have a play with and the spectrum analyser.

Tea, coffee and biscuits will be in plentiful supply all evening.

Looking forward to hearing from you.

73

John

G4RDC

meeting 22nd November: A brief history of RAF ASV radars 1940 to 2010 by Simon Watts G3XXH

All,

Next meeting (22nd November) Simon Watts G3XXH joins us to give us a brief history of RAF ASV radars from 1940 to 2010. (ASV = airborne surface vessel, radar for maritime patrol aircraft)

Venue: Woodford Park Leisure Centre, Woodley, RG5 4LY
Time: 8pm

The history of airborne radars developed in the UK for long range
maritime surveillance by the RAF spans from 1940, when ASV Mk. I entered service on Sunderland and Hudson aircraft, through to the 1980s, when the Searchwater radar entered service on the Nimrod MR2. This history came to an end in 2010 when the Nimrod MRA4 programme was cancelled and the Nimrod MR2 taken out of service. The early radars operated at VHF. Following the development of the high power magnetron, operation moved to S-band and then to X band. Searchwater was a complete departure from earlier radars, incorporating a TWT transmitter, modern signal and data
processing and computer control.

This talk will give an overview of the design and evolution of these
radars, the aircraft they were used in and the performance they
achieved, detecting ships and submarines.

Simon Watts G3XXH is Visiting Professor in the department of Electronic and Electrical Engineering at University College London and formerly deputy Scientific Director and Technical Fellow in Thales UK.

Whilst googling ‘ASV’ I found this interesting link:
https://uboat.net/allies/technical/uk_radars.htm

Min G0JMS also spotted “The Secret of Tuxedo Park” on PBS America talking about the development of radar by Wall Street tycoon Alfred Lee Loomis:

https://www.pbs.org/wgbh/americanexperience/films/secret-tuxedo-park/

Thankyou to George M0GXB for making this meeting happen.

Refreshments afterwards as usual.

73

John
G4RDC