The Farwell MI 2-meter repeater was on a commercial tower about the
equivalent a city block distant from our house when we lived up there.
I did the antenna maintenance. I had to climb around a guy bracket that
was made of either 3/8ths, or 1/2 inch steel that completely enclosed
the tower. Similar plates were used higher up. Guys were 1" and looked
like wire rope. The tension? Hit one at the tower and it'd ring like a
high pitched tuning fork well above middle C.
Whether u-bolted, or wrapped around a leg, using a single leg, weakens
the tower at that point. If engineering determines the tower load is
insufficient to cause a problem, then it's fine, but I wonder what the
insurance co would say if it failed? Now days they have become very
cost conscious and look for ways to invalidate coverage.
73, Roger (K8RI)
On 1/12/2017 10:00 PM, john@kk9a.com wrote:
The guy bracket on larger towers is u-bolted to the tower leg and bracing,
it does not encircle the tower. It is not necessary to encircle the tower.
My Rohn guy brackets look like this
https://www.dxengineering.com/parts/roh-ga65gd
John KK9A
To: towertalk@contesting.com
Subject: Re: [TowerTalk] torque arms or not?
From: "Roger (K8RI) on TT" <K8RI-on-TowerTalk@tm.net>
Date: Thu, 12 Jan 2017 18:16:30 -0500
Although it's a common practice with hams, Guys should be attached to a
bracket, not individual tower legs. It's not normally a problem, but guy
brackets like ROHN sells puts no strain on an individual tower leg. On a
heavily loaded tower,(near its wind load limit), when the guys are
attached to individual tower legs, in high winds, the tower leg on the
windward side takes the strain. With a guy bracket encircles the tower
with the guy strain taken by the bracket and converted to a downward
force, putting far less strain on the tower.
You don't see commercial towers with the guy wrapped around a leg.
73, Roger (K8RI)
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
--
73
Roger (K8RI)
---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|