Guys,
I saw it again. "The tension in the guys will be
equal if the tower is vertical and stationary."
This is absolutely true only in Kansas,
Dorothy--i.e. when the guys are all anchored on
level ground. It comes from the fact that the sum
of the horizontal forces of the guys must be zero
for the tower to be stationary.
I decided to do some calculations on a 70' Rohn
tower with one guy level with the base on the
tower, one two foot below it, and one two foot
above it. (enter SIN, COS and TAN from high school
trig)
Bottom line: Tension in nominal guy 400#, tension
in other two guys are 7 pounds above and 7 pounds
below 400#. You would never see this difference
on a gauge. The statement about equal tension is
close enough.
However, if the guy elevation differences are
severe, expect differences in guy tensions.
Tensioning them all to the same amount in this
case will result in a tower departing from
vertical.
By the way, these 6 guys put a downward force of
1500# on the tower.
Those considering heavier guys (hence higher guy
tensions) ought to consider the impact. Doubling
guy tension will double downward force.
Do you really want to do that?
73 de Brian/K3KO
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