| From: N4ZR <n4zr@comcast.net>
To: TowerTalk <TowerTalk@contesting.com>
Subject: [TowerTalk] Rotator loop - another question
<In my old station, someone came up with this idea - instead of an actual 
<loop, start with the rotator at mid travel and wrap at least two *loose* 
<turns of RG-213 around the mast, then connect to the balun or 
<feedpoint.? It worked fine with no problems in 20 years.
<It seems to me that doing it this way provides physical support for the 
<loop, which could be beneficial in high winds, but when I was putting up 
<my current yagi, people working with me poo-pooed the idea, and so I 
<wound up with the conventional loop.? It hasn't failed yet, but...
<So, what's the informed opinion?
<73, Pete N4ZR
##  That will work, BUT... the yagi has to be high up the mast..and not 1 inch 
above the top bearing.
I have seen  it  done with big coax, like  LMR-1200DB, and also .875 inch 
heliax with yagi high up the mast.
In those cases, the loop was aprx 3 feet in diameter. 
##  another  method, with yagi one inch above top bearing... is  to tape or ty 
rap off the  coax  out onto the boom,
like 2-3 feet  away from the  tower...then leave enough of a loop, with rotor 
at midpoint,  to  enable  360-400 deg rotation. 
Jim   VE7RF
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