From: "Mike Dennison" <mike.dennison@rsgb.org.uk>
Organization: Radio Society of Great Britain
To: rsgb_lf_group@blacksheep.org
Date: Fri, 6 Aug 1999 12:06:55 +0100
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Subject: Re: SV: LF: eclipse
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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