>> Appears that Milt's "fix" helped to maintain the Beverage
>> properties
>> better than the arroyo's >"destructive behavior" by
>> providing bridge for
>> the discontinuity in the ground surface under >the
>> portion of the antenna.
>> Very interesting and perhaps continuation of "open wire"
>> line that
>> >Beverage forms with the ground surface.
> ------------------------------------------------------------------------------------------------------------------
>
> Yuri and others. While the ground plane I construct to
> restore Beverage
> behavior over the arroyos has performed as described, I am
> also convinced
> that the antenna does NOT obtain much "gain" in its main
> lobe from that
> portion of the element..
Of course it doesn't Milt.
That's because the Beverage doesn't work like an "open wire
line with ground".
It works because the poor conductivity earth below the
Beverage allows an electric field to parallel the direction
of the wire. This is actually the opposite of what a
transmission line would do. We all know (or should know) if
the ground wire had high conductivity it would short the
electric field and make the horizontal wire go "dead",
becoming a transmission line.
The other way a Beverage would stop being a Beverage would
be if the conductivity was zero, and the ground was
electrically transparent. In that case the Beverage would be
nothing but a longwire. It would no longer have the response
to the low angle vertically polarized waves directly off the
ends.
73 Tom
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