Quote Originally Posted by Simon Barden View Post
That trimpot may just need a squirt of contact cleaner, rather than replacement. Worth trying that first.

It's not so much that, it's one of those miniature blue plastic PCB -mounted trimpots that has a white plastic centre where the adjustment screwdriver goes, basically over the years I've had the Scope the white plastic screwdriver adjustment centre for the trimpot got a bit worn so that the trimpot has gotten hard to adjust, but yes I could try giving it a spray with contact cleaner.