--IMA.Boundary.686002448
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George Guerin wrote:
>
> Dave and Dave wrote:
SNIP...
> Dave Henderson
> The problem is the 100 ft tower is guyed with uninsulated guy wires.
> This destroys the possiblities for shunt feed unless the tower is fed
> from a guy wire as a inverted monopole.
Snip...
Dick Bodine wrote:
A point of interest! At my former location I had a 75' tower w/TH6 on top. I
did poor planning of the installation by installing guys at three equidistant
elevations and not insulating the guy wires from the tower. However, I did
break them into non resonant lengths. I shunt fed the tower, tapped at the top,
and it played amazingly well on transmit but was very noisy, as most vertical
are, on receive. I suspect the guy wires are adding to the electrical length of
the tower, but I'm not an expert by any means on that subject. Just empirical
data. :-)
snip>
Yes, I agree, if insulators are along the guy wires, even if not at
the tower, the guys will add some loading. Looking at the tower plus
the TH6, the electrical length may have been OK or slightly short, but
if the top guys ran out a ways before the insulators, the additional
loading would definitely make the assembly electrically at least 1/4
wavelength.
George, K8GG
--IMA.Boundary.686002448--
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