Hi VLF,
I'm running another carrier on 8270.005 Hz.
The antenna current is 700 mA, that's 100% of the capability of that
coil. That's about 29 kV across the antenna wire, about 75% of the
voltage limit.
The linear mode PA is now consuming 10.6 A at 25 V, i.e. 265W. I
estimate the PA losses are 65W, i.e. about 200W for the coil and ground
losses. These are 400 Ohm then. The loses of the warm coil are about 300
Ohm. So the ground losses are in a range of 100 Ohm, quite low!
Today i have covered the coil with a trash bag, just to be able to
continue transmitting during rain. The upwarming of the coil under this
bag causes an increase of the resistance which leads to a significant
increase of the needed TX power to hold the 700 mA level...
Markus, Uwe, do you want to join? It would be nice to see 3 peaks from
us showing on one of Paul's nice looking spectrum peaks! Furthermore,
RN3AUS is running spectrograms in 47 uHz and 180 uHz. These spectrograms
are now tracked by PPS+NMEA, whereas it was locked to GBZ/19.58 kHz
during the first detection of my signal.
If all works well i intend to run the carrier until monday morning.
73, Stefan
PS: There are a number of further 'newcomers' trying to detect a signal
on 8270 Hz these days, so its worth to be on the air...
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