[bobsgarage]

Originally Posted by ADTech

The use of the thrust bearing arrangement eliminates the need to limit the stub mast length. That restriction is in place to limit the lateral loading on the rotor motor's output shaft bearing.

WIRELESS ENGINEER is completely correct about the mass of the antenna system that the rotor can handle. When that much mass has to either be started or stopped, there is a tremendous amount of inertia that must be overcome and it will cause the drive unit to fail very prematurely.

For antenna arrays this large, an entry level "ham" rotor is recommended, they're going to start in the $300-400 price range and will probably last a lifetime barring storm damage.

I fear you are correct, the starting and stopping inertial force are too great for the CM 9521A.

I am researching the rotator choices as I have time. As for now, I may set the rotator for it's strongest signal and leave it all winter.

Todays temps are -1 F and wind chills of -25 F with 8" of snow coming over the weekend... Glad I got that rotator changed last Saturday when it was a balmy 25F