But, the more horizontal you make the guy, the less the downward force
the guys place on the tower. This reduction in compression force is
good and could perhaps be traded off for an increase in antenna weight
(assuming the same antenna wind area). In the limit where the guys are
horizontal, there is zero downward force on the tower (assuming the guys
don't weigh anything. I read somewhere where guys are tensioned at many
thousands of PSI.
As Tom says, it isn't magic it's just an application of vectors.
de Brian /K3KO
Tom H wrote:
>
> Fred,
>
> I have to disagree with your statement below. Force doesn't change as the
> guy anchor is moved closer to the tower. The direction of the force
> changes. At a guy angle of 45 degrees the force is 50/50 in the horizontal
> and vertical planes. As the angle becomes smaller (closer to the tower) the
> vertical force increases, while the horizontal force decreases. There's no
> magic at work here! If you could attach a scale at the guy anchor, you'd
> get the same readings at 1 foot from the tower as you would 100 feet from
> the tower. When most of the force is in the vertical plane, the earth
> holding the "dead man" may give up the ghost quicker than when a horizontal
> component is in the mix.
>
> 7 3,
> Tom K3GM
>
> >
> >Tom-
> >
> >Like the ad says, "Wider is better". The figures quoted might better be
> >defined as the "minimum recommended. My guess is that most people would
> >like to have the anchors closer to the tower, if that were acceptable,
> >since they could have a bigger tower with more antennas on a smaller
> >footprint.
> >
> >Think of the tower as a lever arm pulling on the anchor. The closer the
> >anchor is to the base, the less force on the tower it would take to pull
> >the anchor free.
> >
> >73-
> >Fred Roberts, W6TKV
> >Riverside, CA
> >
>
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