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What power tonight ?
G,
00:30 136 DK7FC de SV8RV-1 Op32 Deep Search -38 dB in Zakynthos
(Zante) isl. GREECE
00:25 136 DK7FC de DF2JP Op32 +4 dB F:8% in Meerbusch
00:25 136 DK7FC de SV8RV-4 Op32 -38 dB F:12% in Zakynthos (Zante)
isl. GREECE
00:25 136 DK7FC de SV8RV-10 Op32 -37 dB F:5% in Zakynthos (Zante)
isl. GREECE
00:25 136 DK7FC de SV8RV-14 Op32 -16 dB F:3% in Zakynthos (Zante)
isl. GREECE
Sent: Friday, March 13, 2015 11:58 PM
Subject: LF: LF OP32 tonite
Hi Hugh,
Right now there is someone transmitting OP32 on
LF. I would assume you could detect him.
Just give it a try :-)
73,
Stefan
Am 13.03.2015 21:31, schrieb Markus Vester:
Hi Hugh,
maybe there was no one transmitting... During the last couple of
days, both PSKreporter and opds-32 have been almost bare of LF Opera
spots, with the exception of a single RN3AGC sequence at 18:46
today.
Technically it could also be an exceptionally large deviation
of the soundcard samplerate (more than about 0.4%). But it seems unlikely as
you've been successful on other bands, and also tried different
machines.
Best 73,
Markus (DF6NM)
Sent: Friday, March 13, 2015 9:13 PM
Subject: LF: No Opera decoding on 136kHz
I haven't yet successfully decoded anything with Opera on
136khz in
spite of seeing some very big, clear signals on the waterfall
display.
HF results are very satisfactory, especially on 30m. This problem
applies using any PC or laptop on the premises.
The Rx is the
Kenwood R5000 which produces some images below Long Wave
but sensitivity
is quite good. I use a 136kHz bandpass filter with a
-60dB notch at
200kHz and better than -40dB for all frequencies above
that. The Rx filter
is normally set to 2.1kHz USB and there is a useful
notch
filter.
There is a choice of antenna and preamps. One antenna is
effectively a
sloper, 10M of open-wire feeder at 45 degrees connected to a
horizontal
delta loop of about 140M total length. This can be used with
the Tx
loading coil to tune, or a tuned preamp with about 20dB boost at
136khz.
The other is a 1m square of 10mm copper tube, broadly tuned into an
in-built +10dB preamp which will take about 200mVp-pk input
before
clipping. The earth/ground system is extensive.
Naturally an
alternative receiver would be good but I have nothing
available, the FT817
and FT897 seem quite deaf at LF. Any suggestions
would be
welcome,
Hugh, M0DSZ.
PS: I will probably be on 136khz this
weekend with about 200W dc into a
linear amplifier but will note listening
activity in case it's all
elsewhere.
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