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Ralph Mowery · January 30th 16, 10:19 PM posted to rec.radio.amateur.antenna

"rickman" wrote in message
...
On 1/30/2016 1:24 PM, wrote:
gareth wrote:
One of the problems with beams is the cable winding around
the mast if you try to turn too far in one way or another.

These difficulties have long been solved in the world of radar,
so, has anyone conceived of an infinitely rotatable 50 ohm
coupling for our beam antennae?

Sounds like a $200 solution to a $0.75 problem, i.e. an extra foot or
two of coax to allow slack for turning.

I think the issue is that you have to manage the turning so you don't go
too far in either direction before reversing.

Most ham rotators will not go much over 1 turn. Some will go about 1 and a
half. If you offset the coax about half a turn it does not have to flex all
that much. That is if the beam stops to the north, turn the beam south and
tape the coax to the mast and then go to the other side of the tower and
tape the coax there. Be sure to leave plenty of coax for the antenna to
turn.