In a message dated 98-04-06 14:34:13 EDT, nm9h@ctnet.net writes:
<< Unless you are looking at huge
arrays of 40m beams or greater, the odds of you overloading your
rotator's vertical weight capacity is pretty slim. Let the rotator and
the bearing both do their respective jobs for which they were designed.
>>
Actually the topic of rotator pre-load is one of the most mysterious
I've run into. While knowledgeable mechanical specialists I've talked to think
that there should be some load on a rotator, no one really knows how much or
how to measure it. The manufacturers aren't much help either.
If you've got your antenna and mast vertical load captured by the thrust
bearing, then there is no weight (load) on the rotator. While many people do
this, it may not be the best thing to do, especially since the rotator is the
most common failure mode. BTW, the M2 Orion 2800 is the only rotator that says
anything about this at all and they want to have ALL the weight on the
rotator.
Cheers, Steve K7LXC
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