I have disassembled everything in the meantime (keeping the wiring intact as far as possible), tried to clean the wiring and tag boards as far as possible, measured the transformers and chokes (all good, uff), cleaned all metal parts, transformers/chokes and gotten the replacement components from digikey.
I am waiting for warmer and less damp weather to do the spray painting outdoors.
I did not get around to check the power supply filtering capacitors.
As for handling ground: I will just keep the wiring loom as is, remove the original ground connection to the case, keep the RCA sockets insulated and connect exactly one point (I plan to use the grounded end of the output transformer) to the chassis at the same point where the protective earth will be connected. I hope I can get by without doing any of the tricks like antiparallel high power diodes to connect signal ground to protective earth.
I am waiting for warmer and less damp weather to do the spray painting outdoors.
I did not get around to check the power supply filtering capacitors.
As for handling ground: I will just keep the wiring loom as is, remove the original ground connection to the case, keep the RCA sockets insulated and connect exactly one point (I plan to use the grounded end of the output transformer) to the chassis at the same point where the protective earth will be connected. I hope I can get by without doing any of the tricks like antiparallel high power diodes to connect signal ground to protective earth.
Not necessary. Just connect the OTX ground to chassis ground and to the black speaker post. The wiring loom takes care of the rest. But you need to ground the RCA outer part, or else have a safety ground via the mains cable.
I think we both mean the same thing. By insulating the RCA Socket I mean keep it insulated from the chassis. One connection from protective earth to chassis (which is always the first connection I wire from the mains socket.....) and exactly one connection from signal ground to protective earth. And therefore the RCA outer connector goes to protective earth via signal ground. Just the usual stuff to avoid ground loops.
Oh, I see you did not sand the metal...hmm.
Just curious, did you sand or sandblast the metalwork? How's it looking prior to paint?
Cheers.
Just curious, did you sand or sandblast the metalwork? How's it looking prior to paint?
Cheers.
There is only one photo with the paint removed. I removed the top coat with acetone. Very probably not the original paint. There is some paint left which cannot be removed with acetone, maybe some primer or passivation. Sanding will likely be necessary, but I will do that just before applying the primer. I intend to stay with 1K primer and paint as it can be removed relatively easily if my paint job is not up to standards.