Re: VLF: 8270: now 8269.990Hz

[Paul Nicholson <vlf0403@abelian.org>]

I grabbed a recording from Bielefeld via Wolf's online receiver.

Got the correct message at rank 3721 Eb/N0 = -1.6 dB, BER 41.8%,
there were no stronger false decodes, so that's a genuine detection
at distance 207.6km.

 df6nm to Bielefeld: 358.7km
 df6nm to dk7fc:     174.9km
 dk7fc to Bielefeld: 301.7km

I guess dk7fc and df6nm have the best chance of background noise
(or some interfering signal) being correlated sufficiently to
share a false decode.

Running the Todmorden signal through the decoder with list
length 12 million and -f9 option (linux version only: outputs
all decodes not just the strongest of each phase trial)
produces a few thousand false decodes on a full phase search
and eventually turns up a GL at rank 11802142 with Eb/N0 -9.6 dB.

--
Paul Nicholson
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