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Stefan
You now admit that your antenna is in FACT a LOSSY
DIPOLE and not an earth antenna
g3kev
----- Original Message -----
Sent: Tuesday, December 14, 2010 6:12
PM
Subject: Re: LF: Earth Electrodes
Chris, LF,
Am 14.12.2010 17:27, schrieb Chris:
HiStefan,
Yes, but 600m is VERY long! The wire even
laying on the ground I would expect to radiate quite well at 137 with that
length! And how many watts?? ERP??
I am sure 8970 would do well through the
ground at the sort of powers being spoken about. Probably ideal for
submarines, as Roger says!
Vy 73, Chris,
G4AYT. Well, my earth antenna is grounded at the ends
and TX power was about 250 W. The mode was DFCW-600. The receiver was at
Michael Oexner using a PA0RDT design. ERP? No idea, probably some few uW. Its
not so easy to calculate the losses.
Yes, on 137 kHz the wire length
comes close to lambda/4 and above so it acts not just like a pure earth
antenna but rather as a combination of this and a very loss dipole. On 137, my
power was 100 W at this test.
The antenna was built to do local tests
but seems to work suitable on 137. So it is a fixed antenna, my only fixed
one. And it is a very quiet location. This makes it interesting to use it as a
RX antenna too!...
73, Stefan
-----
Original Message -----
Sent:
Tuesday, December 14, 2010 2:49 PM
Subject:
Re: LF: Earth Electrodes
Hi Chris,
But how do you explain that i have crossed
49.6 km with a 600m spaced earth electrode antenna on 8970 Hz? It was
rather summer time than winther (regarding QRN)! With the same antenna, my
137 kHz signal was seen 20 dB above noise near Paris in
DFCW-3!?????
73, Stefan
Am 14.12.2010 15:15, schrieb
Chris:
Hi Mal,
Yes, that is what I had concluded years
ago. No harm in trying though!
Further to your previous e-mail to LF,
looks to me like beacons are now becoming the norm on 136/7kHz band and
below. I have no problem with that personally, indeed, I think it
preferable to a QSO taking forever! I woud like to see full idents
though, no matter how slow.
Vy 73,
Chris,
G4AYT.
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