My Seeburg 160 with a TSU 5 started doing the dreaded two scans/no record pick ups after working flawlessly for over a decade. Here’s what I noticed: both OA2 tubes were unlit. There was a blow electrolytic cap (10MF/450V) nearby (blown in the sense that the positive end is bulging with some white crud deposits). It looks like it’s C512. All the other caps visually look fine. Someone did a cap job on the unit before I acquired it 25 years ago.
I happened to have a similar electrolytic cap with the same specs so I replaced it to see if the OA2s would relit. I also replaced the 6X4 with one from a working guitar amp in case that was the issue. The new cap & the fuse blew in less than a minute. (Note that I had run the unit with the original bulging cap for a lot longer earlier while trying to figure out what was wrong and the fuse didn’t blow. The new cap is shorted/The original cap is not shorted.) Any suggestions on where to start on this issue? I could replace the cap and fuse and try again but that seems like risking more damage. Start testing all the nearby resistors? Put the original cap back in and see if a new fuse wouldn't blow so I could start testing voltages? (Note: The OA2s and 6X4 have never been changed.) Replace all the electrolytics?
Any help trouble shooting will be greatly appreciated.
jerold k