Tnx Roger,
Yes, my earth antenna is near field. Thus i am optimistic to see my
signal there which might give first impressions about the performance
of the antenna and so. Since i am > 30 dB above noise in 40,0 km
distance (/p kite QTH to my VLF grabber) at 8,97 kHz and at 6,47 kHz
and we are going to the winther period i am optimistic to see the trace
at least there. Maybe some more km can be reached. This can be
estimated after knowing the S/N on my grabber, which is in the far
field :-) Hopefully the RX density in Germany increases soon :-)
73, Stefan
Am 02.09.2010 11:02, schrieb Roger Lapthorn:
Good luck Stefan.
It will be most interesting to see how far you can get without the
assistance of "utilities conduction" as was the case with my own small
tests in the summer. If my understanding is right you have to get
beyond about 25km to be in the far field at this sort of frequency, so
reception at 40km is a good target. I wonder if the effective loop size
(in the ground) increases because of the increasing skin depth and
signal penetration? If so, the results might be better than expected.
I can look at these frequencies with the kit I've already used, but
doubt I'd see anything.
73s
Roger G3XBM
2010/9/2 Stefan Schäfer <[email protected]>
Dear
LF/VLF,
Am 01.09.2010 19:43, schrieb mal hamilton:
Miracles are possible but impossibilities take a little longer.
Yes. Thus is just want to announce some tests on ELF, probably arround
2 kHz. First i set up a grabber window for ELF, still with the VLF
active antenna. I will built an ELF active antenna soon (some weeks).
First tests will be done with the earth antenna (5 km), later i plan to
reach 40 km with the 200m or 300m antenna (using some parallel Cs or
even a mains HV transformer?). Maybe some interesting effects will come
up... Distances will most probably not reach to UK or so but who knows
(before some weeks, no one belived that it is possible to reach almost
50 km with an earth antenna at moderate TX power).
Will there be any interested OMs for that project?
73, Stefan/DK7FC
--
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http://www.g3xbm.co.uk
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G3XBM GQRP 1678 ISWL G11088
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