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[TowerTalk] Nonconductive guys/fixed side mount

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Subject: [TowerTalk] Nonconductive guys/fixed side mount
From: (Pete Smith)
Date: Tue, 16 Mar 1999 13:56:58 -0500
At 10:57 AM 3/16/1999 -0700, Gary McDuffie, Sr. wrote:
>Two questions come to mind.  With the boom-to-mast clamp rotated 90
>degrees from the norm, will it still have enough clamping grip to keep
>the boom from tilting up and down (as opposed to sideways twist in the
>normal config)?  

I think so.  Forces seem likely to be less than in the normal mounting.

>Second, I've never seen any info on any of the amateur
>towers regarding side mounting.  When you mount at other than the top,
>you introduce other stresses.  With Rohn 25, are you getting anywhere
>near design limits?  I doubt that it was designed to have anything of
>size mounted other than at the top.  Maybe I just haven't noticed it in
>the spec.

I found nothing in the Rohn catalogue, but my logic - perhaps specious - is
that the total load is comfortably within the top-mounting spec, and the
5.6 square feet I'm adding will be just above a guy level, with a lever arm
of less than 18 inches relative to the centerline of the tower.

>I'd go with Philly at all levels if at all possible.  Some antennas
>really don't like anything interfering with the pattern.

I have a complete model of my station, including guys.  There is no visible
current induced on any of the guys by the yagis at the top of the tower.
All guys are continuous and grounded at the bottom.  There are induced
currents from my 80-meter array in the guys, but it works so well that I'd
hesitate to change things, just in case the guy wires are part of its
success <g>.

73,  Pete N4ZR
Loud is good

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