Thanks Joe, Markus (and private mailers),
I'm amazed about the very good reception of this system now. DCF39 is
now visible almost 24/7, at good strength, over almost 8000 km. The
DCF39 plot is just amazing i find.
I think i learned a bit from Martin's receive station:
Normally we say "If the band noise is 15 dB above the Soundcard+RX
noise, then the system has full sensitivity (for a given antenna
design, e.g. a wire)".
But i think we have to take a look at the noise after blanking
the strong sferics. If one runs a fast spectrogram, say 200ms/pix. then
we see strong sferics but many other stuff like local QRM between them.
Also the background noise after blanking may be just arround the
soundcard+RX noise. When looking at a slow scrolling spectrogram, even
with a high FFT bin width, the noise looks much higher and so the
system seems to look as sensitive as possible. However the band noise
after sferic blanking is the real important value which must be well
above the soundcard noise.
On this grabber in YV it looks like there is a very high difference
between blanked and non-blanked noise levels, maybe 10 dB or above. I
will check this in an audio recording...
Update for Martin's receptions:
http://dl.dropbox.com/u/19882028/LF/YV7_so_far.png
Who will be the next? O think there must be a advantage of some dB for
UK transmitting stations.
73, Stefan/DK7FC
Am 15.05.2012 13:24, schrieb [email protected]:
It was amazing to see Martin's capture of Stefan's sigs.
Well done, gentlemen!
73
Joe VO1NA
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