ON7YD wrote:
>>A software team from the Belgien amateur radio society UBA has developed
>>a programme that can be used to register the fieldstrength measurements.
>>All you need is a PC with Win95/98 and a soundcard. The audio output of
>>the receiver is fed to the input of the soundcard.
Johan wrote:
>AGC (which is present in most amateur receivers) will make such
>measurements almost useless (unless the AGC can be disabled).
>
>Please correct me if I'm wrong...
I now have this software (thanks, Rik for solving my download
problem). It is just what I have been looking for as it plots the level
of signal, and the noise level if the signal is not permanent. It can
run for many hours and produces a small log file compared to the
huge Spectrogram ones. An 8-hour overnight plot produced a 1M
text file, with each dB measurement dated and timed, plus another
file with much less info which is only 9k! I will post some graphs on
my web site when I have figured out how to convert the text file into
something that Excel can read.
It is obviously optimised for eclipse monitoring, but will be of
immense value in monitoring distant LF beacons to discover by
more scientific means when the regular enhancements are. This
will be especially valuable with that signal from the US which
comes up close to 137kHz at night - as this will give us a really
good lead as to when a EU/US QSO might be possible (or when to
have Spectrogram monitoring for the AMRAD beacon).
Yes, AGC can be a problem, but the program operates fine with
the RF gain set well below the AGC threshold, so if the dynamic
range required is low there should be no problem.
I recommend anyone interested in LF propagation to download this
program - find it at www.uba.be
Mike
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