MF,
About the 630m band dipoles i remember a story:
In late 2008 i started with the 100m kite experiments and used
J-antennas for 160m. That worked excellent. Matching was done with a 28m
long RG58 cable. The losses couldn't have been to high since i run 600W
RF and nothing became significantly warm.
One evening i was in QSO with a German station while it started to rain.
If the kite becomes wet, the wind has to be stronger or at least stable
to keep it in the sky. So it was a question of time until the kite falls
down. It was completely dark and i didn't see the kite.
The QSO partner became weaker and the QRN was down. Later i saw that the
kite was stretched on the wet ground. The SWR was down but anyway it was
possible to hear the other station and it was possible to finish the QSO!!!
That was exactly the location where i did the VLF kite experiments in
2010/11. The ground conductivity must be "fair" there.
So, if this is possible with a J antenna on the ground (should behave
about like a dipole on the ground (?) ), it must work on MF too. Or am i
wrong? That means, for a MF dipole test i would start to try to lay it
on the ground. If this works with reasonable efficiency, so that a QSO
is possible, it would be a simple solution for a quick /p MF antenna
that can find its place in a back pack!
What do the experts think? :-)
73, Stefan/DK7FC
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