In article ,
Bert wrote:

We don't have much trouble with ice here, but long stretches of near-
zero or below-zero F temperatures are common, with occasional dips to -20F
or so.

Would these rotators work in those temperatures? Would they continue to
work for more than one winter?

Some of the ham rotators have their bearing races packed with
low-temperature grease, designed to withstand these sorts of
temperatures without turning into cement.

And, you can open up these rotators and remove the bearings from the
race, clean 'em out thoroughly, and then re-grease them with a grease
of this sort. Reportedly, you should *not* use wheel-bearing grease
or an "extreme pressure" grease loaded up with moly or a similar
fiberous material, as the additive will build up on the bearings and
races... Norm's Rotor Service recommends using either white lithium,
or emerald grease.

The little light-weight TV rotators can also be re-greased. One
review of the Radio Shack rotator suggested that it may not have had
adequate lubrication from the factory (shaft rusted stuck), and that
opening it and cleaning it out and re-greasing it took only a couple
of hours.

Some of the small rotators are said to have plastic gears - these
might not hold up against the torque stress of a medium-sized amateur
beam. Others seem to have metal gears, perhaps tougher.

You might want to install a rain-shedding rubber "boot" above the
rotator... and make certain that the condensation-drain hole faces
downwards, and is not plugged or obstructed!

You might want to see if you can locate a used ham-grade rotor at a
hamfest / flea market, or from a ham who is decommissioning his/her
tower ("silent key" sales, "we're selling the house and moving, come
take it down and take it away" situations, etc.).

I picked up an Alliance HD-73 rotator and a (slightly broken) control
box for a song at a ham flea market a few years ago. 2-3 hours of
work were enough to disassemble it, scrub out what little remained of
the original grease (now about the consistency of grout), clean the
ball bearings, thoroughly re-grease, and reassemble. It's not a
difficult job... but *always* disassemble a rotor while holding it
in a large cardboard box with a sealed bottom. Otherwise you *will*
end up chasing loose ball bearings across the floor, and you'll never
find them all (a cautionary warning I'm glad I read before starting
work!)