Message-ID: <28990.200005121159@gemini>
From: "James Moritz" <j.r.moritz@herts.ac.uk>
Organization: University of Hertfordshire
To: rsgb_lf_group@blacksheep.org
Date: Fri, 12 May 2000 13:06:23 +0000
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Subject: LF: QRN & CW / Commercial CW on LF
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Dear LF Group,
	My homebrew RX has no AGC - instead, I use an audio  
clipping circuit with a variable threshold, which is quite good at 
reducing the effect of QRN, both for normal and QRSS CW. I 
adjust it so that the wanted signal is not quite clipped, but the much 
larger QRN impulses are. I found it was more effective to put the 
clipper before the narrow audio filter I sometimes use. Of course, 
there are limits to what you can expect from this type of circuit - at 
my QTH lately, the static crashes seem to be merging into one big 
crackle!

Regarding non-amateur CW cignals heard on LF, this morning at 
about 1015utc, on 18.20kHz I was suprised to hear VVV VVV VVV 
VTX3 several times, interspersed with figures and letter groups, all 
in plain CW. The signal was about 569. I am sure someone has 
mentioned this station before, but can't think where - any ideas?

Cheers, Jim Moritz
73 de M0BMU