Kevin:

Those 3 wire controllers depend on running a motor in the indicator at the
same speed as the rotator, so indicator accuracy is sometimes less than
perfect (snicker). Most light duty RatShack rotators use that approach.
The rotator itself is typically a split phase AC motor, a common and one
phase fed directly, the other through a phase shifting capacitor in the
controller. Swap the two phase leads for reverse direction. You may want
to consider buying or fabricating a replacement gear to get direction
readout. Or adding a separate direction indicating mechanism. Good luck!

--
Crazy George
Remove N O and S P A M imbedded in return address
"K. Hastings" wrote in message
...
I'm fixing up an older Channel Master light-duty rotor to turn a small 2m
wooden quad I've built for my attic, but one of the plastic gears in the
control unit disintegrated in my hand during the rennovation. The rest of
the control unit is in rough shape too.

I'm thinking of building my own power supply/control unit for this rotor,
but I'm not clear on just how these 3-wire units actually control the
rotor.
Any ideas? I can perhaps make my own simple PS, and figure out the
direction-setting power scheme, but getting feedback on the antenna
position
to prevent over-turn cound be tricky.

Thanks to all who reply...

VE9XYZ Kevin