Message-ID: <001001bfac36$bf721740$5a4401d5@default>
From: "Alan Melia" <Alan.Melia@btinternet.com>
To: "rsgb_lf_group" <rsgb_lf_group@blacksheep.org>
Subject: LF: Spectran ....
Date: Sat, 22 Apr 2000 09:41:27 +0100
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Hi Geri, I also notices a 'spreading' of some signals (abt 0.3Hz). I assumed
I had a Loran-C line at that point as well. Now I'm not so sure......is this
possible an ionospheric effect? I think Andy refered to something like this.
I also wonder whether there might be some processing effect due to the FFT.
The line spectrum does seem to have groups of steady lines in it a bit like
a windowing problem or 'leakage'. I do not get any spreading of a local weak
calibration source (I wonder if it weak enough?)

I have also seen a frequency shift when running another program, and I am
running a much slower machine. (P II 200MHz) What fooled me was that the
signals shifted and stayed shifted when I closed the other program. I was
running a synth calibration signal on the display at the same time, and I
rechecked that frequency on the counter. I now begin to wonder whether the
frequency accuracy (and stability) of the sound card crystals are up to this
kind of use. I have noticed the clock start to run slower when running some
programs. This is particularly noticable on a machine running Win 3.1 (P II
230Mhz)

I was unable to copy the 5mW transmissions over 21/22 April, though I could
detect the signal this morning when the static had subsided. On complete
decodable charcters where seen.

Thanks Marco for an interesting experiment.
Cheers de Alan G3NYK   JO02PB
Alan.Melia@btinternet.com