Hello Wolf,
Thank you for watching!
Your vlf6 remote site will make it at least after 3 days i bet.
It is not good to turn on the blanker anyway because Paul could find
better settings in a post-processing. I assume he is so kind to help us
:-)
It may not be easy to find the best blanker and filter settings for
this special frequency range. I choose 1.57 kHz because the far sferics
'end' at 1.6 kHz (down to DC) but using a sharp band filter would not
be good. So what is ideal?
Instead of a spectrogram, you know, generating a spectrum peak is more
promising. Actually a 1 character EbNaut message is the most efficient
way to go anyway, because a clear decode of 1 character can have less
S/N than a doubtless spectrum peak.
The first 24 hours without a interruption are now completed.
I'm excited!
73, Stefan
Am 26.04.2018 20:41, schrieb Wolfgang Büscher:
Nothing seen here on a 2nd PC receiving the raw signal from VLF6 with a
higher resolution spectrogram, but that's no surprise with the recent
QRN / thunderstorm activity.
Unfortunately the low-power netbook that streams VLF6 to Paul's server
is too slow for running a second SL instance. And for the VLF audio
stream, I don't want to turn on the noiseblanker before the Vorbis
encoder, because this would make listening to the stream very
unpleasant.
But keep fingers crossed, maybe the 191 km wavelength signal gets close
to the '2 lambda' distance..
Cheers,
Wolf .
On 25.04.2018 22:05, DK7FC wrote:
ULF,
The system changes have been done now. The carrier was off again
between 17:43...19:00 UTC.
>From now on there will be no significant ( > 1 min) interruptions
any more.
The carrier can run up to 3 weeks, depending on the feedback. Possible
known RX stations are DL0AO, DL4YHF, Paul and Renato(vlf.it).
73, Stefan
Am 25.04.2018 13:56, schrieb DK7FC:
ULF,
Unfortunately i forgot to remove the stop command from the last day, so
the carrier stopped again at 10:30 UTC. It is back since 11:50 UTC.
Just a note for those few who try to watch out for the signal.
73, Stefan
Am 25.04.2018 11:04, schrieb DK7FC:
ULF,
After 9 hours of work the carrier is now back since 01:00 UTC. I'm now
running the actual target level of 56 mA, so the signal should
be 6.3 dB stronger now.
Eventually i'll have to do some worke work tomorrow but maybe not.
The carrier will stay on the air for a few days without interruptions
if all works well!
Reports welcome :-)
73, Stefan
PS: Forgot to send the message last night (morning actually), must have
been tired ;-)
Am 24.04.2018 10:49, schrieb DK7FC:
Hello ULF friends,
I just opened up a new band by starting some activity on 1570 Hz
! It is the 191 km band! :-)
Since 8 UTC a carrier is running at 1570.01 Hz. Soon the first trace
will appear on a spectrogram from my tree which is in 3.5 km distance
from the transmitter.
See the developing trace at http://www.iup.uni-heidelberg.de/schaefer_vlf/DK7FC_VLF_Grabber2.html
The spectrogram scrolls with 10 minutes/pixel.
The carrier will stay on the air for 2.5 hours. It is just a first
test. So far the antenna current is just 27 mA but tonite i'll try to
reach the target level of 58 mA which means 12 kV again acros the
special iron cored coil. This will mean about 120 nW ERP then.
DL0AO is already watching the band. I hope to be received by Paul and
at the reomte site of DL4YHF. I'm not planning to do /p RX experiments
on that band, just focusing on these 3 RX stations.
73, Stefan
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