Hi Paul,
Did you get some more improvements? From the known decoded EbNaut
messages, what was the SNR at Renato or on your side?
Your recent sferic analysis seems to state that no unexpected
propagation effects are present, e.g. groundwave/skywave cancellation
over wide areas and times? So it would be the plain signal attenuation
and local QRN/QRM situation that affects the decode.
How many stacked daily 2.97 kHz transmissions do i need to get a decode
of 5 characters in Cumiana and/or Todmorden? What's your estimation?
...i would like to continue on the 101 km band again...
73, Stefan
Am 25.01.2017 19:30, schrieb Paul Nicholson:
> f = 2970.000000 Hz
> Start time: 25.Jan.2017 07:00:00 UTC
> Symbol period: 30 s
> Characters: 5
> CRC bits: 16
> Coding 16K25A
Decoded at Bielefeld via DL4YHF (303.8km). Copied 'DK7FC' with
Eb/N0 +4.5 dB and constant reference phase.
S/N 19.1 dB in 29.8 uHz, -60.1 dB in 2.5kHz.
I'm still working on the recordings from the weekend. Gained a further
3dB by using very strong hum filtering, a threshold only 1.5 times the
mean amplitude and narrow notches. Enough to suppress not just the
harmonics but also the sidebands of the harmonics. Still no trace
here in Todmorden - yet. Still some permutations of polarisation
and azimuth to try.
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