> I'd say that given "average" elevation angles for DX, you
should treat both
> arrival elevation angle and tilt from ground loss as being
roughly equal
> factors.
None of that matters anyway Chuck when the pattern of the
antenna isn't any good. We know a lot more about antenna
patterns and how antennas respond over earth than we did
back in the earlier part of the 20th century.
The fact is we want the horizontal area of the antenna to
have as much response as possible. If we put a wire below
the antenna that *really* changed things we know by where it
is located it could only make things worse.
A Beverage responds in the horizontal area only because of
the high loss in the media below the antenna. Without a
highly conductive media below the antenna, it's a cloverleaf
with a null off the ends caused by the vertical ends
dominating the response.
It's all in the antenna pattern. We can have all the tilted
wave we like but if the antenna has a zero response slice
looking at it and major lobes 20dB stronger 45 degrees to
either and off both ends, we won't be very happy with the
results.
The only thing that prevents people from shooting themselves
in the foot with the wire below the Beverage is the wire
couples to the lossy media below it so well it becomes very
lossy, and of course that means it doesn't help with
stability or termination.
If you think it does, lay a very long wire on the ground and
measure the input impedance. See how it looks compared to a
~50 ohm ground rod connection....I guarantee it won't look
pretty.
73 Tom
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