Dear LF Group,
A happy new year to all - I have been without E-mail facilities over
Christmas, so have just spent a couple of hours reading through
the 260 or so e-mails that had accumulated - mostly from the LF
group! It might take a while to digest all of it.
I didn't have a lot of time for radio things over the holiday, but like
several others I was able to copy VE1ZZ most nights - best
reception was during the early mornings of 25th and 26th of
December. The limiting factor on signal quality at my QTH was
QRN, which perversely was much higher than it had been in the run-
up to Christmas. I was quite suprised that the signal strength could
vary as quickly as it does, sometimes 5 minutes is all the
difference between good copy and unreadable signals.
I look forward to the tests of the 12th/13th, and will certainly be
taking part. As far as frequencies go, the best bet as far as I can
see for the EU side is using the bottom band edge as we did
effectively in the autumn - provided we avoid the frequencies used
by SXV, this should avoid interference to other users in Europe,
and is the favoured part of the band for Canadian/USA listeners.
The 136.5kHz frequency in use by VE1ZZ is probably OK, provided
nobody decides to fire up on CW; but usually activity is low late at
night. So I plan to use either 135.715kHz, or 135.916kHz
depending on what SXV is doing, or unless somebody else
desperately wants to use these frequencies.
Something else that would be worth clearing up is what dot lengths
will be in use - VE1ZZ has made use of rather short dots, which
works OK for his signal . But since he appears to have a much
higher ERP available than any European station, it would probably
be best if everyone else stuck to 3s dots. In any case, it would
help to know in advance, so that software settings can be
optimised.
I also got my BPSK receiving gear going over Christmas- I now
have a W&G SPM19 level meter with homebrew external
preselector and demodulator, feeding one of G4JNT's PIC
interfaces to VE2IQ's "Coherent" software. The SPM19 has an
ovened reference with 10e-7 stability, and 1Hz tuning steps. The
demodulator uses the reference output to synthesise the BFO
frequency, maintaining the overall stability, which should therefore
be more than adequate. I have not yet received any off-air signals,
but loop-back tests with a signal generator and BPSK modulator
worked fine; I am now working on the transmitter - I just hope that
everybody does not lose interest before I get the whole thing
finished! I am a bit sceptical about the "Grab" feature of Coherent -
the longer the grab length, the less random the output data seems
to become, even with just noise being fed into the demodulator
input.
I saw quite a few unusual modes on 136kHz; Andy's SMT-hell, what
I presume was PSK31from DK8KW and friends, and something
which seemed to be the key-clicks of a CW signal, without the rest
of the signal, when looking at 136.5kHz.
I worked G3KMP for the first time on 136kHz - Colin expressed an
interest in getting active soon on 73kHz, and being located in
Hastings, he should be easily within range of a number of people;
as before, I intend to be active on 73kHz on Friday evenings, if
anyone else wants to try out their new NoVs.
Cheers, Jim Moritz
73 de M0BMU
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