For comparison to Paul's graph, here is a simulated
spectrum of four repetitions of the emitted qrss-60 "XBA1" sequence, total
duration 4 x 55 minutes.
All of the taller peaks are visible in Paul's
received spectrum. This suggests that it should possible to demodulate
the sequence, using temporal averaging, comb filtering, or even simple
magnitude thresholding of spectral bins.
Best 73,
Markus
Sent: Sunday, March 02, 2014 6:54 AM
Subject: Re: LF: Re: U.S. VLF License WH2XBA
Here is a four hour integration of the signal in 69
uHz bandwidth
http://abelian.org/vlf/tmp/29499_140302a.gif
Keying
sidebands begin to become significant at this resolution.
The signal may
be a little stronger than advertised, I still have to correct for the signal
thrown away in the sferic blanking.
-- Paul
Nicholson --
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