M0BMU wrote:
I made 3 recordings of IK5ZPV's "Wolf" signals on 137.5kHz last
night; one made between 2000 and 2025utc produced no decoded
results, however the other 2, from between 2100 and 2200, both
decoded without problems after the 2nd and 3rd data frames
respectively.
I also made two recordings but failed to decode either. In both cases the pm
figure was zero, and the f was 0.980, whatever setting I used for -r and -f. I
am fairly sure this means I was not receiving a signal. This is in marked
contrast to the recording I have from a few days ago when I get sensible pm
and f readings even when there is no readability.
I will be away from Thursday for ten days, but will try to record Valerio tonight
and Larry in the small hours of the morning. Is there a way to make recording
on a timer - I don't think that Cool Edit will do this?
After I return from holiday, I will do further work on WOLF. I am gradually
getting to know what the data readouts mean, and how to recognise when I am
nearly decoding a signal. I am still not convinced I have -r correct but attempts
to set it by scientific means have all produced poorer results than by trial and
error.
As a further suggestion to the software kings, having a few seconds of
unmodulated carrier built into the transmission every now and again would
help the receive station to determine whether a signal is present (using a
spectrogram). Now, I can't tell the difference between poor readability and no
signal.
Mike, G3XDV (IO91VT)
http://www.lf.thersgb.net
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