I have from previous guitar incarnation a 40 year old 20 watt “Loco by Aria” amplifier which was crackling a bit as I moved any volume, tone or other variable resistor. Sometimes cutting out almost, then coming back a lot louder without me doing anything.
So I bought contact cleaner and had previously tried to trickle some down the shafts of these after talking off the knobs. Without disassembling the amp. Made a bit of a difference.
Did not fix.
So bit the bullet. Took the back off and disconnected speaker and spring reverb. After taking a photo to remind me of the right connections.
Undid a few screws holding in the circuit board and pulled out. Undid screws holding power transistors to heatsink to get access and blasted the pots through the tiny holes in the back of them with the contact cleaner. Spun the shafts a number (10) of times.
I bet a lot of people would have just given it up as “broken” in our throw-away society. Tinkering seems to be a lost art, despite the fact that it can probably fix at least 75% of basic issues that crop up with all sorts of equipment. Glad to hear you had a go and got it sorted.
Nice! Love to hear about tinkering gone right (and occasionally gone wrong )!
Would be nice to see more posts like these where people can exchange ideas about repairs or show a photo-log of something they did! Or even a dedicated section of the forum if there are enough posts
I had the same issue. I also treated it by removing the knobs and spraying in the cleaner. I also took the back off in the hopes of gaining access to the pots and the insert hole. Sadly the inner construction was such that it was not obvious how to do that. Now it is back so maybe more research and then must bite the bullet and look into this again.
)!