James Moritz said
I worked through the FS figures I measured last week on 73k - it comes out
like this:
G3AQC 130mW ERP
G3LDO 85mW ERP
M0BMU 100mW ERP
Rugby 73.25kHz 7.5kW ERP
Bearing in mind that for all the signals apart from my own, deviation of
up
to +/-3dB could be expected due to relying on only one field strength
measurement, and that I have not attempted to include ground wave losses.
So amateur signals are roughly 50dB down compared to the Rugby FSK signal.
If the receiver is using about 0.01Hz bandwidth to obtain a few dB SNR (ie
a visible QRSS signal), then the FSK should have at least 6dB SNR in 300Hz
BW, so be an easily audible signal.
Jim's figures look about right. I was running about 800w and I figure my
antenna is about .01% efficient.
I hope to get a new or repaired third module for the Decca Tx this week and
should be able to get up to 120mW erp if I also get a better PSU!
I wont be on 73kHz tonight or tomorrow.
Regards,
Peter, G3LDO
e-mail <[email protected]>
Web <http://web.ukonline.co.uk/g3ldo>
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