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Thanks a lot, Alex, for two reports in one -
the traces on 137780 were actually the one-hour dashes of my
"M".
Unlike for VLF, due to the
frequency conversion in the receiver it is not easily possible
to distribute a "one-fits-all" SpecLab USR for LF. In my case, the situation is further complicated by the dual-channel
colour-DF scheme, and the odd way I lock my RX
samplerate to an accidental (but deterministic) 876 Hz spur from the LO
DDS. Here's an excerpt from a recent exchange with VE7TIL on the
topic:
>> Scott, the slow SpecLab settings
are fairly straightforward - I use 11025 Hz samplerate, complex
decimation by 768, FFT size 32768, and 600 seconds per
FFT. The center frequency and display offset will depend on your
receiver's precise LO frequency (watch out for DDS rounding errors).
Finally you will want to inject a known audio tone for
samplerate tracking (eg. GPS-derived 5 kHz), or alternatively
1-pps pulses plus NMEA (which I haven't tried yet).
Best wishes,
Markus (DF6NM)
Sent: Saturday, September 24, 2011 12:51 PM
Subject: LF: DK7FC, DF6NM, UA0AGC and very slow transmission on
137780
Hello LF, Stefan, Markus!
There are screenshots
with signals DK7FC, DF6NM, UA0AGC and very slow transmission on 137780.
I
would like to rx-experiment with such "QRSSSS" :) . Probably, someone has
approaching *.usr file?
73 de rn3aus/Alex
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