Hi Dave,
My point is the only way to reduce loss with a vertical near earth is
to provide a conductive path for the currents back to the antenna
area as evenly as possible over a large area that extends quite a
distance out in all directions. How the currents "got there" doesn't
matter much, the fact is they will always be there with an antenna
near earth. That's true even if we insulate the radials, or elevate
them a small fraction of the operating wavelength.
If we want a good ground system that always works as well as
possible, we shouldn't leave earth areas larger than .025 wl without
conductor coverage. Spread the ground system out as evenly as
possible for as far as possible, and forget the magic that often does
not really work.
It all comes down to the large area covered in many feet, not the
area in inches between radials and around the antenna base or how we
connect wires. A twenty-foot radius dense woven screen might just as
well be twenty 20-foot radials, so far as a vertical antenna is
concerned.73, Tom W8JI
W8JI@contesting.com
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