View Single Post
  #9   Report Post  
Old January 30th 16, 10:32 PM posted to rec.radio.amateur.antenna
[email protected] jimp@specsol.spam.sux.com is offline
external usenet poster
 
First recorded activity by RadioBanter: Jun 2006
Posts: 1,898
Default Rotatable couplings?

rickman wrote:
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.


Commercial rotators only turn +/- 180 degrees.

If you are building your own, adding limit switches is far simpler,
cheaper and more reliable than a rotary coupling.

As the supply of WWII and Korean war prop pitch motors has pretty much
dried up and they cost more than a used commrcial rotator ready to go,
I don't see much motivation for building a rotator from scratch these
days.


--
Jim Pennino