>I wonder if two conductors will obtain the "shielded from the outside world"
>effect >refered to above? Does it make any difference?
Herb, my suspicion is that two drop wires will act more like a folded dipole
than acting like a full skirt...
I expect it will take a minimum of three wires at 120 degree spacing to begin
to act like a coaxial skirt - and it will be leaky...
If you want a true skirt you will need a number of drop wires, 4+, with cross
ties around the skirt at least every 1/16 wave... Certainly, you can get some
benefits as a fatter conductor from fewer wires and no cross ties so the effort
is not wasted, but I doubt you are getting the full skirt effect...
A few years back I spent considerable time and effort fooling with drop wires,
folded uni-poles, varying spacing and diameter of wires, etc. using my quarter
wave stick as the support.. They all worked but none of them are still up -
which speaks for itself... W8JI and I had some repartee over these issues on
this reflector, as I remember... I was at one point using the folded dipole at
varying spacings from the tower to act as an open sleeve element for driving
the tower...
Doing a full skirt around the quarter wave, 160 tower is still on the to-do
list, just waiting for it's turn... But, it will be done a bit differently
(like every thing I do)... It's purpose will be so that I can remotely tune the
electrical length of this vertical element... There's more to the story, but I
tend to rattle on too much anyway...
cheers ... denny - k8do
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