Hello Paul, VLF,
Am 06.05.2016 02:24, schrieb Paul Nicholson:
Stefan,
Your 200mA carrier comes through well here at 6.47 kHz, nice
signal at 0.14 fT during the night.
That is very nice. Can you show a graph showing a spectrum peak with
noise and signal in a reasonable bandwidth?
I'm very happy with my VLF remote grabber, have been impressed by the
low man made noise levels above 5 kHz. The diurnal QRN is much lower on
6.47 relative to 8.27. I hope this can be an advantage.
Yesterday i have been on the tree, completing the installation of the
E-W single turn loop which is now used.
Daytime is 0.04 fT or
below and might be a bit of a struggle.
Oh, such a difference. What could be the reason, propagation? What
day/night ration can be found on 8.27?
It would be interesting to get the information which band is 'better',
when assuming a current limited TX system. On 8.27 kHz the ERP will be
2.1 dB higher then on 6.47 kHz. But maybe the phase stability and
diurnal propagation (in a range below 2000km) will be better on 6.47
kHz. On the other side, the average RX system will have a higher man
made noise level there.
I don't need any more carrier. From the raw recording I can
optimise filters and blankers and look at most of the diurnal.
OK, i'm looking forward to your EbNaut decodes of my two transmissions
:-) With 0.14 fT there is a real chance i think. As i know you, i think
you want to wait with the presentations of your decodes until you've
found the best filter+blanker settings to get the best SNR possible.
My next goal is of course the 58 km band, 5.17 kHz, where i have been
active just 2 times ( i think) in 2010/2011. Then, i will go lower for
the first time. New land!
73, Stefan
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Paul Nicholson
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