At 02:28 PM 4/7/1999 -0500, Terry wrote:
>
>Note that George W2VJN and Pete N4ZR are both talking about having
>the guy wire INSULATED from the top of the tower and noticing interaction
>(actual or modeled, depending upon the story-teller) while K4VX is
>talking about the guy wire CONNECTED to the top of the tower. Regardless
>of the validity of modeling, it is certainly true that having an insulator
>right under the antenna at the top of the tower results in a high-impedance
>point probing a location with maximum RF - thus tending to maximize any
>potential problems whereas with connected guy wires there will tend to be
>at least partial cancellation of the fields caused by the three guy wires
>and the tower.
Interesting point, Terry. In my case, the top set of insulators are 21
feet long. Still, that could be why modeling shows they are so disruptive
for my planned lower antenna in the stack, because those ends of the
grounded guy wires wouldn't be that far from the plane of the lower yagi.
Just for fun, I'll try lifting the ends of the guys off ground (in the
model) and see if that changes things, also try connecting them to the
(modeled) tower. I want to shunt feed the tower on 160, though, so in real
life it has to stay insulated.
73, Pete N4ZR
Loud is good
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