If this rotor is anything like some of the JA-made rotors I've seen in the
past - where a comparotor looks at the indicator pot & then drives a
motor in the control box to move the indicator - a previous post with the
suggestion of using coax for the indicator lines makes sense. A little
induced crud on those lines would tickle the comparator & indicator then
goes on walkabout. Cheaper RG-6 CATV drop cable may be the ticket
for folks with long runs.
Dodgy connections between the indicator pot & the comparator are
another potential culprit. If so, one should find some correlation between
wiggling cables or connections & indicator movement.
Likewise, problems with the indicator pot should have some amount of
correlation & consistency with antenna movement.
Crud coming up the mains might be finding its way to that comparator, so
the Yaesu suggestion may not be entirely snake oil, but does sound like
a wild guess unless undesired indicator behavior was coincidental with
something that would suggest mains was a potential route for whatever it
was that was getting in.
It's been nearly 15 years since I last dealt with one of these motorized
indicator boxes, but I think my solution at the time was to bin it & instead
use a control box with a meter.
Break out a CRO & take a peek at what's happening around the op amps
should something more obvious not rear its ugly head.
If none of the above is relevant to the problems folks are experiencing at the
moment, hopefully it will prove useful to someone trolling the archives later.
73, VR2BrettGraham
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