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Hi Joe, LF,
during the last couple of nights, opds detected all
of your transmissions between about 22 and 7:30 UT.
Attached is a zoomed 40 mHz section from my
opds-32 spectrogram, showing your central coherent carrier which
contains half of the transmitted average power. It seems to be about 0.5 mHz
below 137477 Hz (possibly due to a calibration error in my receiver). The
2.7 mHz spaced sidelines during the early part (bottom) were caused by
6-minute-periodic interruptions from my own MF WSPR transmissions. However the
little curls near the carrier can presumably be attributed to Doppler-shifted
multipath components. The carrier was still weakly visible for another hour
after the last detection.
Comparing the looks of the carrier to earlier
IZ7SLZ transmissions, the stability of the signal and the path seems quite
sufficient for half-hour EbNaut PSK transmissions. Unfortunately I missed
the opportunity to save the raw data and analyze phase evolution using the
EbNaut decoder itself - will try that next time.
All the best,
Markus (DF6NM)
Sent: Saturday, November 07, 2015 12:03 AM
Subject: Re: LF: last night opera opds detection in
km07ks
LF Group,
I am grateful to Joe DF2JP for his captures
QRSS and Opera
Dionysious SV8RV for his OP decodes to Domenico IZ7SLZ
for
his OPDS decodes, and thanks to DF6NM for opds!
I do not know if my DOCXO
is stable enough for EbNaut.
It was set a couple of years ago and has not
drifted more than
1 Hz since then. It seems the phase decoherence has
stopped
haunting me.
I am hoping to replace the halyard for the other
100m wire soon.
OP32 again tonight as send this
email.
73
Joe
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