01-11-2018, 12:59 PM
i had carbon trace on two of my loctals,, one was the 7af7 and the other was another which was cherry to get to and repair.
the easy one to get to was the first i found, so i didnt have spare loctal sockets at that time.
I took the loctal apart, laid the insulator disc on 2000 grit sand paper and sanded down past the carbon ditch it made.
I taped off and sprayed the exterior of each pin with spray electrical insulator, (comes out redish in color). put it all back together and that got rid of my reistance to ground on the one pin that was messing me up.
I found the carbon trace on the bottom side of the disc insulator by the way, it was not on the top.,,, so the only way to see is to take it apart.
lucky for me i was told to tone each pin to chassis to see if i had this possible fault and sure enough one pin was reading a few hundred ohms to ground.
the easy one to get to was the first i found, so i didnt have spare loctal sockets at that time.
I took the loctal apart, laid the insulator disc on 2000 grit sand paper and sanded down past the carbon ditch it made.
I taped off and sprayed the exterior of each pin with spray electrical insulator, (comes out redish in color). put it all back together and that got rid of my reistance to ground on the one pin that was messing me up.
I found the carbon trace on the bottom side of the disc insulator by the way, it was not on the top.,,, so the only way to see is to take it apart.
lucky for me i was told to tone each pin to chassis to see if i had this possible fault and sure enough one pin was reading a few hundred ohms to ground.