GM Gerhard, VLF,
Am 22.01.2011 10:54, schrieb Gerhard Hickl:
20db over noise at 40km distance is very good and probably the strongest
signal you have ever seen from me Lubos. That signal should be audible
and enough for CW.
I don't think so. I've recorded my own signal from the kite antenna on
my grabber in 40.0 km distance (
http://no.nonsense.ee/qthmap/?qth=JN49IS36VH&from=jn49ik00wd ). The SNR
was about 40 dB but it wasn't audible. I think 50 dB SNR in 4.5 mHz is
necessary to get a R3 audible CW signal, depending on the kind of noise
within the CW filter bandwidth.
Local conditions are good, -2 centigrade and in the moment nearly no
wind. I hope wind isn't becoming a problem during the day.
Unfortunately the noise is rather high here in Heidelberg, compared to
the last days. No signal visible so far. But we know about the
propagation effects in some 100 km distance. Maybe your signal will come
up in some hours. Looking forward to that :-)
I will try to keep the TX running until evening.
Good luck Gerhard!
73, Stefan/DK7FC
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