> In all the stuff I've read about current chokes, feedline radiation due
> to asymmetry, etc. I don't think I've ever seen this possibility pointed
> out (or thought of it). If coax can pick up RF and reradiate it, why
> not the rotator cable? (A disturbing thought, why not the tower too?
> Pretty difficult to wind it in a multiturn coil.)
There is a reason you don't hear of that problem much, although I agree it
is possible.
The coax connects DIRECTLY to the antenna element.
The Rotor and tower are only close by, and obviously are coupled to the
antenna significantly less than the feeder. This is particularly true when
the antenna is electrically balanced and symmetrical about the tower.
This is why a tiny amount of common mode noise on the shield is a big
problem, and other cables or the tower itself is not.
73 Tom
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