There was an interruption of the carrier between 5:28...5:48 UTC. This
was again by reaching the -20 mA safety limit. It was just due to rain
which pulled the resonance to much downwards, despite the phase meter
driven transductor which can compensate a drift of up to about 25 Hz in
this frequency range.
A few more interruptions and phase reversals are shown on the tree
grabber but these were only on the RX side, a restart of the Raspi was
done after 2 months of errorless operation.
A second attempt of the longer message:
f = 6470.100000 Hz
Start time: 19.Apr.2017 07:00:00 UTC
Symbol period: 4 s
Characters: 30
CRC bits: 10
Coding 16K25A
Duration: 3h, 48m, 16s
Antenna current: 460 mA
73, Stefan
Am 17.04.2017 22:38, schrieb DK7FC:
PS:
Carrier on air since 20:05 UTC.
73
Am 17.04.2017 22:36, schrieb DK7FC:
VLF,
Now the coil resonance is right on 6470 Hz. A + 5 Hz or a - 5 Hz step
is leading to a lower antenna current. The carrier will stay on air for
at least 1 day, that's the plan. An EbNaut message will follow, if all
works well.
I'm still staying at 460 mA antenna current. The actual frequency is
6470.005000 Hz.
With the 6.2 dB stronger signal relative to my last experiments a few
months ago, Paul may get a more precise measurement of the diurnal
phase changes...
Hopefully there will be a trace at RN3AUS but maybe this is not
realistic?
73, Stefan
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