At 07:44 AM 12/29/02 -0600, n4kg@juno.com wrote:
>Another 80M vertical option is a K8UR style 4 square
>using 4 V's hanging sideways off the tower. Again,
>if you have LONG conductive guy wires, they will
>most certainly interact with any vertically polarized
>antennas around the tower.
My 80m lazy-vee parasitic array was originally supported on a 97' tower
with three yagis and three sets of conductive guys, all insulated from the
tower and grounded at the guy anchor. Later, to accommodate a stack of
tribanders, the top guys were replaced with Phillystran. Both in models
and in real life there was very little difference in array performance
before and after this change. Moreover, the guys showed relatively little
current. The tower, on the other hand, shows major excitation by the array
-- in fact I think it is a major reason why the thing works as well as it does.
I think the moral is at least model the thing before acting on a
generalization, however good that generalization may be in most instances.
As far as 160M options are concerned, an inverted L suspended from the
tower, maybe 4-5 feet away, is another option much recommended to me when I
was doing my shunt feed. I opted instead for an omega match and a
convenient tap height, using the match to "find" 50 ohms without a lot of
tower climbing. Works like a dream.
73, Pete N4ZR
Happy Holidays
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