Tom:
I think that Fred's original response is indeed be correct, as is
yours. You are relating a different aspect of the situation. Fred is
not referring to the tension that you may crank up in the guy wire, but
rather the tension that is exerted IN the guy wire by a given horizontal
force applied to the tower. For a given horizontal force applied by the
tower, say 100 lbs, a greater force will be required by the guy wire to
counterbalance it as the angle of the guy decreases. Try working out
the vectors. From prior experience with guying sailboat masts I know
this to be the case. Guys, or shrouds as we called tham, carried
tremendous loads if they were positioned closer to the base of the mast.
73 de Mike, AA3RL
------------------------------------------------
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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