G3NYK wrote:
To Mike yes I do use the steady signals of the 'beacons' for tests, but what
does S9 mean?? Its a strong signal but is it 10uV/m or 1V/m. Most of the
radios I have have S-meter sensitivity controls so you can set S9 at
whatever you like! I'd love to tell you by how much you have improved your
system.
OK, I agree this is very crude system, especially as some rigs, like
my IC-706, have black squares representing each S-point or each
'10dB' over 9. So there's no prospect of getting real numbers out of
it - unless properly calibrated - but it can help as a very crude
measure, especially as you know the signals you are checking are
not only in the far field but have some sky-wave, too. There's no
substitute for doing it right. Of course, a nice compromise is the
Selective Level Measuring Set - when I think of the SLMSs and
other test gear (capacitance bridge, 1Hz resolution VFOs, LF
fundamental crystals) which I put in a skip when I worked for a
telecom company a few years ago, it makes me cry!!
Thanks for the report on the main signal and the spacer.
Just a thought as you are using a mixer source...have you tried keying one
crystal oscillator? I find that quite clean and stable. It might be an easy
mod.
Actually, I still use a straight Clapp VFO and a two-transistor
Buffer/Keying stage. I like the two-crystal (XO +VXO) system but
haven't got round to building one yet - have tended to concentrate
on the size of the signal.
Mike, G3XDV (IO91VT)
http://www.dennison.demon.co.uk/activity.htm
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