> Why would a Beverage respond to vertically polarized signals anyway?
> With a Beverage over perfect ground and a zero degree arrival angle,
> there would theoretically be no induced signal in the antenna.
The Beverage actually responds to the voltage gradient caused by
attenuation along the ground, which is just another way of saying the
wave tilt.
That tilt or voltage drop along the lossy earth is the same for
groundwave signals as it is skywave signals.
It doesn't matter how we look at it, the result is any vertically
polarized signal will excite the entire antenna, including the short
vertical ends or the long horizontal middle. If vertically polarized
signals didn't excite the horizontal section, the antenna would not
be useful at a few feet height!
The reason you don't see the low or zero elevation angle sensitivity
in a model is because most programs we use calculate the field at a
very very large distance and that prevents the plot from having any
response along the earth, unless you put in perfect ground. (But if
you do that, the Beverage will quit working in the model because
attenuation along the ground will be zero, so there will be no
"tilt".)73, Tom W8JI
W8JI@contesting.com
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