>From Dave G3YMC
If Spectran and the other programs offer the capability to copy stations
20dB below noise, in these circumstances this would only take you to s9,
which was certainly copyable with normal CW. I admit the static levels
recently have been much higher than usual, and would not expect anyone to
attempt to work transatlantic under such conditions (or to even ragchew!)
I have two weakish carriers on the band, 136.7 and 137.8 which are
normally just above the noise. I wonder how copy of these is on Spectran
with 20dB over heavy static - I can just about copy traces here in the
crashes.
This misses the point. Spectrogram etc can copy CW up to 20db
below 'normal' noise. But the duty cycle of static is much lower
than noise, therefore there is a =much= greater advantage than
20dB. Using Spectrogram and QRSS, I can receive signals 100%
in heavy static that would be impossible to read using normal CW
at whatever speed.
But in any case it is really up to the individual operator to use
whatever technique he feels happiest with, and regardless of what
technique is used, S9+ QRN is going to degrade it. Also QRSS is
no good for ragchews, no matter how good the S/N is.
I will try to demonstrate the advantage of QRSS in static by
providing a WAV recording and Spectrogram plot on my web site
(which make me the only LF operator hoping there's QRN tonight!).
Mike, G3XDV (IO91VT)
http://www.dennison.demon.co.uk/activity.htm
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