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Re: [TowerTalk] Feedline Coil or Loop??

To: <k7lxc@aol.com>, <towertalk@contesting.com>, <k3bz@arrl.net>
Subject: Re: [TowerTalk] Feedline Coil or Loop??
From: John Elsik <wa5zup@msn.com>
Date: Mon, 23 Jul 2007 14:16:48 -0600
List-post: <mailto:towertalk@contesting.com>
How about three RG8 size cables?  Would that cause any coiling/uncoiling 
problems?
 
John
wa5zup> From: K7LXC@aol.com> Date: Mon, 23 Jul 2007 15:50:32 -0400> To: 
towertalk@contesting.com; k3bz@arrl.net> Subject: Re: [TowerTalk] Feedline Coil 
or Loop??> > > In a message dated 7/23/2007 12:13:41 P.M. Pacific Daylight 
Time, > towertalk-request@contesting.com writes:> > > I've always used a 
feedline "loop" that hangs out and down from the tower > leg that's half-way on 
the rotation circle, is attached to the boom a few > feet out from the mast, 
and is long enough that it doesn't impede antenna > rotation in either 
direction. I recently saw an installation with the > antenna mounted about 2 
feet up the mast from the tower top, with the > feedline coiled about 2 turns 
loosely around the mast rather than hanging > down. The antenna end of the coax 
was attached at the bottom of the > mast-to-boom plate. The arrangement looked 
like those coils of cable that > the TV trucks deploy when they raise their 
microwave towers, but only a > couple of turns to the coil. When rotated
  in one direction the coil got > tighter to the mast, but not touching it. In 
the other direction the coil > got looser.> > > My question is.... is this a 
good idea? I have never seen it before, so > maybe it isn't in widespread use, 
which makes me wonder why not.... as it > "appears" that it would put less 
stress on the coax than the usual U-shaped > arrangement.> > You betcha. It's 
an alternate method that works FB and is a little more > foolproof than a 
conventional rotation loop. I think the reasons that it's > not used more is a) 
many people don't know about it and b) it takes a little > more thought and 
planning to do. If you've hauled up the feedline with your > beam, getting it 
around the mast a couple of times might not be easy. OTOH you > can spin the 
beam on the mast a couple of times to do it. > > I've used it many times. It's 
easier with one or two cables - more > starts to cause coiling/uncoiling 
problems. > > Cheers,> Steve K7LXC> TOWER TECH > > > > > > > > **
 ************************************ Get a sneak peek of the all-new AOL at > 
http://discover.aol.com/memed/aolcom30tour> 
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