Hi Paul, VLF,
Fine, a nice result!
There's not so much margin left. What would hve been the shortest symbol
length to get a decode on your side?
And can you tell something about the signal stability? 25 dB in 10 uHz
looks ufb. I'm using that E field pick up probe to feed back the
radiated signal to the soundcard, so the whole system (soundcard, PA,
coil, antenna wire) becomes part of the PLL. The probe is a simple
unshielded piece of RG174 cable, abt 0.1 m long, in a distance of 1m to
the antenna wire. so far i have no idea if this improves the phase
stability or maybe even reduce it?
I saw no announcements for a transmission by DF6NM, DL3NDR or DJ8WX (why
are only German stations transmitting on VLF these days?) this morning
and it is sunday, so i started a simple carrier transmission at 07.05
UTC at 8270.00500 Hz. The low QRN period must be used :-)
And, Gary/G4WGT has started a 47 uHz SL instance on his VLF grabber.
Maybe i can leave a small trace there this morning.
73, Stefan
Am 01.05.2016 07:51, schrieb Paul Nicholson:
After the full message duration had elapsed,
Eb/N0 came to +1.6 dB,
Phase: 180 180 150 150
Carrier S/N: 24.96 dB in 10.3 uH
Were the last 3 hours corrupted? Without signal,
the decoder pads with zeros and these all count
as errors for Eb/N0 calculation. If signal
is present but wrong, only 50% of the missing bits
will be errors.
--
Paul Nicholson
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