I may have found it. I certainly have found a sickening sight. The red and green
screen pots were pristine.
The blue one looke like the object on the right.
The whole inside was filled with rusty goo.
I have cleaned this up and the resistor element seems perfect.
The baclk of the control is, as is visible, pitted.
The gooey part of the slider can't arc to the back as its grounded too. But
the slider or element could arc to the case or the slider shaft.
I am adding a bit of shrink wrap on the shaft and a mylar
sheet to insulatre the back.
http://videokarma.org/attachment.php...1&d=1484420473
Time will tell.