[TowerTalk] Coax and cable loop at antenna

[Pete Smith N4ZR]

I don't know if there is any magic here, but this worked for me for the 
last 15 years. I have done this with both RG-213 and RG-8X.

I used Scotch 88 electrical tape to secure the coax to a tower leg near 
the top.  I don't know why that wouldn't work with your 220MM mast - you 
could put a big plastic cable tie over one layer of tape and under 
another, for sun protection.  Then I led the cable over to the rotating 
antenna mast and, with the antenna at mid-rotation, I wrapped 3 turns 
loosely around the antenna mast.  Finally I taped the feedline to the boom.

My Yaesu rotator turns a total of 450 degrees, but with this arrangement 
the rotator loop is supported by the antenna mast, essentially just 
loosening and tightening around the mast as the antenna turns.  Our 
climate is fairly benign, but after all these years of lots of sun and 
temperatures from -15C to +35, the original tape still looks good

The other common approach is a single 180-degree loop in the vertical 
plane, long enough so that it can wrap around the mast as the antenna 
rotates without running out of length before the rotator stops. I prefer 
the wrapping approach because it seems to me that it flexes the cable 
less at any given place.

73, Pete N4ZR
The World Contest Station Database, at www.conteststations.com
The Reverse Beacon Network at http://reversebeacon.net, blog at reversebeacon.blogspot.com,
spots at telnet.reversebeacon.net, port 7000 and
arcluster.reversebeacon.net, port 7000

On 9/9/2012 9:29 PM, Frederick Mott wrote:
> I installed 2 runs of 7/8 helix cable on the inside of my tower and I used
> SS cable ties.  Plastic ties (I don't know of any good UV protected plastic
> ties) will rot away after a few years of sunlight.  As far as your cable
> length, add enough cable to  make a loop between the tower and your antennas
> so that the cables will not be stressed.  Use your judgment or better yet
> buy some good antenna and or tower books/publications from the ARRL.
> Fred, AB8AH
>
> -----Original Message-----
> From: Rick Kiessig [mailto:kiessig at gmail.com]
> Sent: Sunday, September 09, 2012 8:08 PM
> To: towertalk at contesting.com
> Subject: [TowerTalk] Coax and cable loop at antenna
>
> How do you figure out how much coax and control cable to put between your
> rotator and the antenna?
>
> How do you secure those cables on both the tower side and at the antenna?
>
> What kind of coax do you use there? BuryFlex or something else?
>
> I'm also looking for a good way to secure cables to the outside of the
> tower. I'm not using a Rohn-style with multiple smaller support posts.
> Instead, it's a single pole, 220mm in diameter. I'm reluctant to just use
> long plastic cable ties. Is there a better approach?
>
> 73, Rick ZL2HAM
>
>
>
>
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