On Sat, 3 Aug 1996 K7LXC@aol.com wrote:
> [...]
> Actually, mounting the rotator farther down the tower is a good deal;
Not so fast there, Steve...
> mounting it at the bottom of the tower is even better. The reason is that
> the mast acts like a spring (a big torsion bar) and absorbs much of the
> twisting force before it reaches the rotator. The practical problem is the
> length of the mast and coupling it plus the additional cost.
Don't forget the additional wind load from a long mast. A 2" OD mast,
6 feet long, is another square foot of wind load, even if it's inside the
tower. If you are already overloaded (who isn't?), better to keep the
mast length inside the tower short.
The Rohn book even reminds you to count the feedline(s) cross-section in
totalling up your windload on the tower, if I remember right.
Big Don
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