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
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