Johan wrote:
> 24 dB S/N is "armchair copy".

Well that 24dB is a 5 hour integration in 55uHz.  It
makes a big sharp line on the spectrum though.  At
VLF that counts as 'armchair'.

> It would be interesting to actually listen to a
> spectrally shifted and time compressed version of
> the signal.

> Can you do that on your Linux box Paul?

No problem.  5 hours compressed into 22.5 seconds
and frequency shifted so that 29499 Hz is moved
to 400 Hz.  wav format 32k samples/sec mono 1.4 Mbyte

 http://67.207.143.181/wh2xba1_140303a.wav

How good is your 'CW ear' I wonder?

Purposely I haven't filtered it too aggressively so
you can apply your own filter to suit your ear.

--
Paul Nicholson
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