Hi Bill,
Thanks for the thoughtful and technically good reply.. I have solved the
problem (until next time)... I do speak op amps, etc. so I understand their
circuit, and I was totally puzzled over the behavior... I was thinking about
broken/intermittent windings in the transformers, broken traces on the
circuit board, cold solder joints, etc...
I put a temporary pot on the back of the controller, in place of their pot,
and proved that the controller (s) is fine and that the motor rotated the
ring (helper watching the beams)... while doing this I had an analog meter
(thank goodness it was not a digital) monitoring the wiper on their pot and I
saw the needle flicker... after we rotated 360 deg both ways, the wiper
settled down and it is now fine... When the wire harness was put back on the
controller, the controller continued to work just fine... I suspect that
there is a speck of foreign material in the pot and the wiper would ride up
on top of it, breaking contact with the resistance element momentarily, which
caused the controller to malfunction... by the time I would disconnect the
wires to ring the circuit, the rocking in the wind, etc. would wiggle the pot
back down into contact again, and look perfect..... what a setup to drive me
banannas.... All of this is taking place in cold temperatures, which may have
some bearing on this...
I hope that it will behave until better weather.... Tic has sent me a new pot
and nylon gear... They have been cooperative, if a bit disorganized...
Denny
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