Hi Steve
Your way is much better of course if you can run the double guys. The only
benefit of running the single guy to a "Y" is that the resulting force
vector associated with the twisting moment is no longer completely
perpendicular to the tower and so you get a slightly greater horizontal
component to the force that is attached to the "star" bracket that will
resist the torque load. As the tension in the guy increases due to the
twisting of the tower, the horizontal component of the force in the Y
increases faster than the horizontal component of the guy if it is simply
attached at the end of the triangle.
73
Bill
W7VP
----- Original Message -----
From: "Steve Maki" <StevesLists1@gmail.com>
To: "towertalk" <towertalk@contesting.com>
Sent: Friday, November 07, 2008 10:04 AM
Subject: Re: [TowerTalk] Guying a self-supporter
> Bill wrote:
> <snip>
>
>> One thing I have done with my own tower is to build a triangular bracket
>> which is attached at the base plate of the rotator. The bracket is
>> attached to the tower legs so that each leg of the bracket is attached
>> to two legs of the tower. This give a longer moment arm for the guys to
>> pick up the rotational moments of the antenna system. Even better would
>> be to create a "Y" in the guys near the top so that the moment from the
>> rotator is picked up at an angle on the base thus increasing the
>> effectiveness of the guys in resisting rotational moments.
>
> The best method for rotational resistance is to run double guys up to
> your "star" bracket. My 190' Rohn 80 has 2 levels of double guys with
> star brackets and is engineered for four full blown cell sites, (48)
> 1-5/8" feedlines, plus 2 full size 40 meter beams.
>
> I can't quite see how a Y in the guy near the top will resist rotation
> very much...
>
> Steve K8LX
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