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Hi All
My argument is that a vertical antenna has the
advantage over a loop at the same height out in the open ie the middle of a
field. Some others are discussing environmental issues like verticals and
loops in amongst trees, buildings and other RF absorbing obstacles.
The facts are being distorted because of
local environmental issues instead of comparing the two antennas on LF where
both systems are small physically compared to the
frequency.
Only those with sufficient
unobstructed space are in a position to test one against the other for
a true accessment.
In reality most radio amateurs have to cope with
small gardens, bushes, trees, adjacent buildings and telegraph poles etc, so
they make the best of their situation, but on LF this can be a problem with
antenna installations and one has to use a CONVENIENCE antenna rather than
the ideal and it might well be that a loop in some cases wrapped around trees
works better for some than a vertical lying up against the same trees but these
circumstances are not valid arguments for a true accessment of comparing
verticals against vertically orientated loops.
Although I do have some high trees on my property I
have several acres tree free for antenna testing.
and have found the vertical a lot better and easier
to tame, easy to match using a series inductor and tuned against an
insulated ground radial system to match 50 ohms, and manageable RF current to
get up to 1W erp radiated power. To try doing the same with a vertical loop
at the same height would require 50 + amps RF and I would not even consider
this approach at this power level.
73 de Mal/G3KEV
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