At 18:28 98/03/19 +0000, you wrote:
> I am wondering how a half-sloper for 80m suspended from a 25m high tower
> effects the shunt-fed operation of that same tower for 160m, and
> vice-versa? Didn't find anything in the various books I have on the
> shunt-feed method.
>
> 73 Alex PA3DZN
Hi Alex,
I am currently using this combination system of half slopers for 80m
and a gamma matched shunt fed tower for 160m. One sloper wire are pulled
down toward South-East and another toward North-West. These wires can be
selected by a relay at tower top (20m). Unselected wire goes opened.
The influence appears only when switching a sloper wire to a NW one while
operating on 160m, shunt fed tower looses it resonance and SWR goes high.
As long as selecting SE wire of sloper which was selected when I tuned
a gamma VC, shunt fed tower remains fine as I expected.
My experience tells that a shunt fed tower is much influenced by things
what are suspended around a tower, but its can be managed by remaining
things as it was tuned.
No affection on 80m sloper resonance by a shunt wire is observed.
73 Watt JA0DAI (also WR3W)
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