Pete Smith wrote:
> For whatever anecdotes are worth, I'm turning a Force 12 C-3/Short 40
> combination with a pinned G-1000SDX, and have not had any signs of trouble
> in 3+ years, including some pretty fierce winds. Since the Yaesu design is
> not a worm gear drive, and the brake drum is a very small device without
> the wedging design of the T2X-style, my hunch is that in a real pinch the
> brake drum will simply slip, at least until things hit the stop at one end
> or the other of rotation. Maybe they assume that in most cases the antenna
> will windmill into equilibrium before that occurs.
The thing that saves our undersized, overrated, pinned rotators - at least
on Rohn 25 & 45 style towers - is the twisting of the tower itself, which is
VERY substantial.
Anyone not convinced of this need only position himself at the rotator while
someone else turns the beam and stops it. There is a very pronounced
cushioning effect on towers at least 50' or 60' in height. IOW, we do our
undersized rotators a favor by using them on undersized towers <g>
OTOH, I've never found it neccessary to pin CDR-Telex-Hygain rotators, because
their clamps can handle the needed tightening force. The Japanese style
rotators need pinning without a doubt. And it would be so easy for the
manufacturers to correct that problem, without even scrapping the cast
aluminum uppers, by wrapping the upper with steel (u-bolts with plate
ala Hy-Gain, or some other method).
--
Steve K8LX
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