>> > I was wondering if anyone has
>> > tried to put a grounded wire 2-3 ft below their entire
>> > As Milt
>> > did over his arroyo runs. Would this change the apparent
>> > height above
>> > ground?
>
> 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..
The velocity factor of the aluminum fence wire grid forming the ground plane
is not significantly different than the copper conductors I use for the
Beverage elements. Also, the ground plane is removed from its proximity to
ground for most of its span. For all intents and purposes, that portion of
the element is just a piece of 2-wire transmission line.
Consequently, the arroyo spanning portion of the Beverage run performs as a
Beverage element would when constructed over very good conducting earth.
Most likely it is nearly the same as having the antenna element over a sea
watered salt marsh.
The ground plane is to prevent the portion of the Beverage element suspended
over the arroyo from acting like it is a "long wire"; a piece of wire placed
high enough above ground that it responds to signals from all directions.
My experience with this "fix" has been very positive.
However, that portion of the Beverage element now contributes very little
increase the signal level in the main forward lobe.
Everyone have a good weekend. I am working on preparing the multi-op
station for CQ 160 CW. The team hopes to work all of you in the BIG one of
the year.
Milt, N5IA
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