I laid out 1000' of #14 stranded, insulated wire. I terminated it with a
200 ohm resistor to a 1/4 wave wire and several short radials running
nearly parallel to the antenna/grounding wires. At the feed end, I used a
4/1 homebrew transformer using one of "Tom's" binocular cores. The
transformer was grounded to a conventional 8' ground rod.
The antenna never worked at all, as far as I could tell. There was no
discernable, certainly not usable, directivity. Why, I don't have a clue.
The techniques chosen were the result of all the best advice I could get
at the time on the topband reflector.
I'm afraid antennas like that are severely length constrained, because they
are slow wave structures.
The velocity factor of an antenna laying on or surrounded by ice is pretty
slow. This will limit how long you can make an antenna before the pattern
falls apart.
Insulation will not mitigate this problem, because the issue is the
proportion of electric field in the media (ice) around the antenna compared
to other dielectrics.
If we consider the dielectric constant 3, maximum length would be 250 feet
and it would be quite length critical. Too short or too long and pattern
would fall apart.
The impedance is also a lot higher than you might expect. It is nothing like
a BOG laid on normal dirt. It doesn't even act like a Beverage because of
the extremely slow wave velocity.
73 Tom
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