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Re: counter wieght queistion

Bruce Nolte wrote

A counterweight is used to balance a dish or antenna assembly when the
center of gravity is substantially either forward or behind the center or
rotation of the elevation rotor. For example,  a 1.2 meter dish which weighs
50 lbs might have its center of gravity when the dish is pointing to the
horizon say 9 inches from the center of rotation of the elevation mast would
produce 9/12 * 50# = 37.5 ft lbs of torque which the rotor would have to
overcome to raise the dish.

Wayne Estes replies:

It is also common to use use other antennas as a counterweight for a dish.
My 60cm G3RUH dish doesn't have anywhere near the weight of a 1.2m dish.
But I compensate for the dish/downconverter weight in front of the crossboom
by having more yagi/feedline weight behind the crossoom.

A counterweight would definitely be prudent for a dish-only rotor setup.  No
matter how powerful the rotor, it will last longer if the load is balanced.

Wayne Estes W9AE
Mundelein, IL, USA

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