OPEN UNIVERSITY AMATEUR RADIO CLUB
NEWS LETTER no:15
G0OUR Affiliated to the OU Club and the Radio Society of Great Britain
please make a note in your diary of the forthcoming AGM. As usual, it
will be held in the Green Room above the Lecture Theatre at Walton
Hall. This area has been refurbished following adjacent building works.
Access is via the door at the end of the Airport Bar, up the stairs and
first right. The AGM is on Tuesday 14th January at 12.30pm. All
subscriptions are due on the 1st of January, and remain at £6 per
annum. Your continued support for the club would be much appreciated.
am pleased to report that we purchased a ladder back in July. We
managed to obtain it second hand from a local plant hire firm that was
recommended by our Chairman, Ted G0CGC. The ladder is a 2 x 5.5m heavy
duty aluminium type, and is ideal for our purposes, i.e. reaching the
top of the tower when it’s telescoped down. We also bought a hefty
padlock and chain, so hopefully it won’t suffer the same fate as the
last one. Our thanks go to the O.U. Club for providing funding to buy
the ladder (£150).
The aerial repair and maintenance work has
now been completed, just in time before the winter weather. The most
difficult job was repairing the break at the feed point of the top
doublet. This entailed loosening off the boom support clamps and stub
mast coupler, and dropping down the fifteen foot extension pole above
the beam. This in itself doesn’t sound too tricky, but manipulating a
fifteen foot pole above you while being twenty five feet up a ladder
makes it a hairy experience, despite wearing a safety harness. Getting
the extension pole back in position after the repair job was no picnic
either, but all was completed safely and without incident.
balun was fitted to the cross bar just below the rotator, which feeds a
pair of parallel dipoles for 80 and 40m. The 40m dipole being suspended
about 5 inches below the 80m one. Tuning the 40m dipole was
surprisingly tricky and time consuming, not only altering the lengths,
but the distance between the dipole ends and the 80m wires proved to
extremely critical. Each adjustment meant lowering and raising the
tower and retensioning the dipoles, and four or five iterations were
needed before the 40m resonance fell nicely in the middle of the band.
A good match was obtained on 40m, but not so on 80m, where the swr at
resonance is about 2.5:1, presumably due to the 40m dipole positioning,
so some further work is needed. The big topband doublet works very well
on 80m anyway, so it’s not a major problem. The old 80 dipole has not
been re errected since it too caused severe detuning of the 40m aerial!
The balun and feeder remain in place, so it can be reused in the
future, perhaps for a WARC band dipole.
While the tower was down
we also took the opportunity to replace the old 2m groundplane, and
this has been returned to Tom G3LMX, and is now being used at Bletchley
Park. Thanks for the long term loan Tom! Also, congratulations to Tom
on being appointed MKDARS station manager at Bletchley Park. Our new
aerial is a dual band colinear mounted on a wooden crossbar at the top
of the tower, giving 4.5dB gain on 2m, and 7.5dB on 70cm. This is fed
with W103 low loss coax, and then via a diplexer into the two radios.
Very good results have been obtained on both bands, with excellent
coverage on FM of the immediate area and beyond. Some good contacts
have also been had on 2m SSB despite being vertically polarised. We
have still not managed to obtain a 70cm linear. We have chased after a
few, but have always been too late. However another one has now been
located second hand, which we hope to purchase in the near future.
to Adrian G1NIQ who recently obtained his class A callsign M0ANS (which
he had pre booked by the way!). He becomes our first member with an M
series callsign. Adrian took his Morse test locally at Bletchley Park,
having attended Morse classes there run by the MKDARS. He had his first
HF contact from the club shack on 20m CW, and is now quite active from
home on 40m CW and has made many contacts throughout Europe using a
long wire aerial.
Welcome to new member Matthew Walden from
Hampshire (R0197702). Matthew holds the callsigns G4XWV and AE4PH, and
can be contacted via packet @ GB7VES, or Email 101732,3044 @
Compuserve.com. He is about to embark on T102. Matthew becomes member
number fifty in the all time membership list.
Not much has
changed on the packet front, the node continues to provide good
service, touch wood! The TCP/IP port has been taken off air, and the 2m
radio put back on 144.675 on the AX25 node. Unfortunately there is some
problem whereby packets are being lost somehow between the TNC and the
PC serial port, so the 2m port is currently transmit only, not very
useful! Hopefully we’ll sort it out in the near future. We have hosted
a number of further MKPAC meetings in the Cellar Bar at the O.U., the
next one being due on Monday 16th December at 8pm. OUARC members are of
course very welcome to attend. There seems to be some progress towards
siting a node at Bletchley Park, at least to aid DXCluster access to
DXI or DXH, and a meeting has been proposed for Friday 10th January at
MKDARS for all interested parties.
The club station was active
for the last hour of the Club Calls Contest on topband in November and
we submitted an entry for the first time, so look out for the callsign
when the results are published. A total of 66 SSB contacts were made,
25 of them being with other UK club stations, so the event certainly
‘put us on the map’ alongside other clubs. Perhaps next year we can put
in a more serious entry and get closer to the top of the list. The club
station was also activated during the CQ WW CW contest, making many
world wide contacts, and more recently in the ARRL 160m contest where
we worked a dozen or so stations ‘across the pond’ with good signals.
we did not make the MKDARS boot sale this September as the members who
normally organise and man the stand were unavailable for various
reasons (holidays etc.). Arrangements were made to sell some of our
‘junk’ on another stand, but in the event we were let down and no money
was made. We have continued to collect for future sales, and in
particular thank Jim G7HUE who has been having a clear out, and has
also donated some useful amateur radio books to the club. Hopefully
next year we will be more organised and be able to make a few bob for
The last lunch time video was ‘Aerial Circus’ by the
late Dud Charman G6CJ, back in November. This video shows practical
demonstrations of different aerial configurations scaled for 3GHz
operation. Although a bit dated, this black and white video gave a very
interesting insight into the way aerials work. If you haven’t seen it
and you get a chance to, it is thoroughly recommended.
lunch time video will be ‘Amateur Television’ on Tuesday 21st January,
as usual in room N2028 Venables Building at 12.30pm. This is a sixty
minute video comprising a series of short programs on amateur
television, both in the UK and in Australia. Guests are very welcome.
have had a number of enquiries about the club from students who are
starting with the O.U. in the new year, so hopefully we will get some
new members as a result. Members are reminded of the Thursday lunch
time meetings in the shack from around 12.30, it would be nice if more
members made use of the excellent facilities we now have in the shack
for HF, VHF and UHF. Finally a reminder of the Pavilion Bar meetings on
the first Wednesday lunch time of each month. That’s about it for now,
have a good Christmas, and please try not to forget the AGM! 73...
Contact: Adrian Rawlings email@example.com