[Amps] Cleaning and lubrication of ribbon variable coil

[Rob Atkinson]

It sounds like what you have is a Harris edge wound coil with pinch
rollers.  These are often found in phasors and ATUs.  When they have
been set in one contact point for decades, freeing them up and
returning them to new condition usually requires they be completely
disassembled and cleaned up, (Tarn-X) and put back together with some
dielectric grease on moving parts.  Nothing on the coil-roller contact
surface.  When reassembling take care to get the pinch roller to grip
with the right amount of force.

73
Rob
K5UJ