>I am curious if there are directional improvements to be
>gained with Beverage
> antennas with respect to height above ground? What changes
> at 6 ft, 8 ft or 10
> ft? How important is it to have the height consistent over
> the entire length of
> the Beverage?
I don't find much difference with height as long as height
is less than .02 wavelengths or so. This is for long
Beverages over what probably is medium conductivity earth.
When Beverages are short or poorly terminated a lower height
will help because they have slower wave velocity. This
increases the electrical length, and reduces vertical end
contribution that will deteriorate pattern on a short high
Beverage (the EWE effect). A low height antenna also has
more distributed loss, and that means it can't be as long as
a higher antenna before it runs out of current at the far
end.
This is my observation from locations where skywave noise
dominates the noise floor, not local noise.
My ~5-6 foot high antennas are not noticeably different
than 10 foot high antennas on 160, but the lower ones are
noticeably better on 40 meters.
If you are looking for a sweet spot there probably isn't
one, and I would do a side-by-side test with equalized
levels.... NOT just looking at noise....because noise and
signals will both be weaker on a lower height antenna and
that can easily give the impression the lower antenna is
better. A lower antenna will be always quieter...but it will
also have lower signal levels.
73 Tom
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