KLH Model 21 found at Goodwill today!

[jr_tech]

Originally Posted by Captainclock

According to a thread on AudioKarma where a guy had a unit that had the same exact issue as mine (where it hummed and no audio minus the blown fuse issue because mine hasn't blown its fuse yet surprisingly enough) they said something about the amplifier's coupling caps being bad which then in turn caused the output transistors to become fried like bacon, and once he replaced the coupling caps on the amplifier board and replaced the output transistors it worked fine for him. I'm hoping that's not what happened with mine because the amplifier board is going to be darn near impossible to remove because for some reason or another the amplifier board's mounting screws are covered in solder so there's no way to unscrew them...

Well I guess I can forget about working on the tuner board specifically on the vernier tuner mechanism because the screws wont budge and the heads keep wanting to strip out on me whenever I try to remove them, which tells me they used poor quality aluminum screws for that part for some reason, which is odd because the rest of the screws they used were stainless steel screws...

I'm guessing that the screws that attach the amp board to the heat sink might be filled in with solder to prevent removal... these *should* be left intact. the screws that hold the board/heatsink assembly to the chassis are the ones that need to be removed to remove the amplifier.
Try a better screwdriver on the tuner screws. Do you have any "Liquid Wrench" ?

jr