On Sat, 12 Sep 1998 10:53:18 EDT K7LXC@aol.com writes:
> The mast is the lever arm and the pivot point is where it
>contacts the
>top of the tower. The mast and antenna load is trying to pry the
>bottom of the
>mast that's attaced to the rotator in the opposite direction with LOTS
>of side
>force.
The side force actually depends on how the antennas are
distributed on the mast, and how far down in the tower
the rotator is installed.
To determine the rotor side force(lbs) for each antenna, calculate
the following:
windload(lbs) x antenna-to-bearing distance(ft)
--------------------------------------------------------
bearing-to-rotor distance(ft)
Consider the windload on the mast as another antenna at half
the length of the protruding part of the mast.
Add up all the resulting forces to get the total side force on the
rotor. The answer is the same regardless of whether or not the rotor
is supporting the dead weight of the antennas and mast.
Dave Hachadorian, K6LL
San Diego, CA
K6LL@juno.com
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