I think you can go a bit further with that Alan. If you have a really
long, low, wire then the current is returned via the ground, penetrating
down to skin depths. The result is a big loop, with the dimensions of
(effective) skin depth * length of wire. So resulting in vertical
polarisation.
This was (still is ??) the type of antenna used by the US at ULF (67 Hz, 81
Hz ???) for their submarine communications. Wires that look like
overhead telephone cables disappearing for hundreds of km into the distance!
If you want a bit of fun reading conspiracy theorists ranting, do a Google
search for "ULF" to find out about the government's mind numbing radiation
experiments !
Andy G4JNT
hear some of the pundits sharpening their pencils....it is actually not
that
simple, as the ground level is not the level of the "Earth-plate" you must
take into effect the skin depth of the ground at this frequency. This is
dependent upon the frequency and nature of the soil. Thus at ELF (< 3kHz),
the type of antenna you think of will work quite well (compared with
anything else) the skin depth is proportional to the frequency but the
radiation resistance is proportional to the (frequency)^2. I think you said
you ground was poor, sandy. That would work to some extent if there were no
surrounding lossy "environment"....like trees shrubs and houses. I suspect
this is why the VK antenna across the valley that Bob describes works so
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