Dear group,
Do others hear (or see) a continous carrier on 472.5 kHz as well ?
I first thought it was 'local' but since it's only there in the
nighttime, and even suffers from QSB like the 'wanted' signals it must
be from a distant transmitter. Don't think it's an intermod product in
the receiver, because the signal is audible with an SDR-IQ and a Perseus
as well - not just with the old IC706 which I use at DF0WD for reception
on MF.
If this frequency is audible / visible in other parts of Europe as well,
we may have to move the de-facto CW 'calling frequency' a bit... maybe
by 50 Hz or so which makes it easy to tell an answering call from this
carrier signal (which sometimes sounds like Morse but in a spectrogram
one can see that it never disappears 'completely').
73,
Wolf DL4YHF / DF0WD
JO42FD .
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