At 05:27 PM 11/23/02 -0600, you wrote:
>Another method that I can envision is to have the coax come off the mast and
>tower PARALLEL to the horizon and do the loop in the horizontal plane. Now
>the coax will coil and uncoil versus twisting.
>
>Would this be better for the coaxial cable in the long-term?
Actually I asked about this not long ago. Here's what I was told.
You'll notice that the television remote trucks have a rotating dish on the
top of their pneumatic masts, and they coil the semi-rigid UHF coax around
the mast a number of times on the way up. As a result, a 360-degree turn
in the unwinding direction just loosens the coil on the mast somewhat.
I actually use a hybrid of the two methods on my yagis, one of which has
450-degree rotation. My rotator loop is about 2 turns of non-rigid coax
(RG-213) that is wrapped around the mast, with the rotator against the stop
where it is almost tight on the mast. Unwinding 450 degrees then loosens
the turns but does not entirely unwind them. In retrospect, next time I'd
use 4-5 turns. On the other hand it's been up 7 years...
73, Pete N4ZR
Sometimes a tower is just a tower
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