A local ham called me this evening and ask me for help with her rotator
wiring. She and her husband had replaced her operator desk and had
disconnected the rotor wiring from the box without labeling the wires. They
could not get the unit to work again. They had a part of a Tailtwister
manual with no wiring diagram that they "thought" came with the used rotor.
They think the unit is an older Tailtwister. It's mounted up about 40 feet
with about 100 feet of standard rotator cable back into the shack. It was
about dark when I got there, so we could not go up the tower (I can not now
anyway due to a hand injury). In the twilight, the unit looked like a Ham-M
to me. My Tailtwister looks bigger and black, theirs looked smaller and
gray. Not as small as my CDE 45 though. The indoor box has a two tone
color METAL case. There is no Break release light and the on/off switch is
a knob. Mine has a on/off lever and a brake release light. I don't think
it had the red CCW and CW lights either. It does have the three sets of
finger switches, CCW, brake release, CW. ANY IDEAS ON WHAT TYPE OF UNIT IT IS?
My manual shows the following connection : 1 large wire to motor
2 large wire to brake
3 wire to one side of direction
4 wire to CCW motor coil
5 right limit switch
6 wire to left limit switch
7 wire to other side of direction
pot 8 wire to CW motor coil
I did find two wires with 320 ohms between them (instead of the 500 ohms per
my manual) and found what I think is the wire to terminal 1. I measured
about 320 ohms between what I think is 1 and 7 and about 320 between 1 and
3, which indicates that the rotator is turned all the way "south" to one
side. She thinks it is North though.
When I got the wires hooked up, and replaced the blown meter fuse, it read
South on the right side. I'm starting to wonder is we had the calibrate
function selected (did all the units have a calibrate function?)
I connected what I thought were wires 1,2 3 and 7. I can get the brake to
release and get an indication on the meter.
I also found one wire that appears not to be connected to anything, which
makes me believe that one of the limit switches in open. There was a lot of
wind last night.
Thinking that a limit switch is open, I tried bypassing them but I think I
got screwed up. Should I wire what I think is wires 4/6 to both terminals 4
and 6 and what appears to be wires 5 and 8 to both terminals 5 and 8? Or am
I totally confused?
What happens if we get both motor coils shorted together and apply voltage
across the parallel coils?
What is the DC resistance of the motor- about 6 ohms? That seemed to be the
difference between the resistance between what I thought wires 1-8 or 1-4
measured versus 4-6 or 5-8.
Any help would be appreciated!
Ralph N4TG, email@example.com
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