All, I'm bringing this one to the top, again;
My not knowing just what to do, and all the mention of how clean 5050s are to be kept, I dropped the amp board and cleaned all the connectors. It helped but didn't solve the issue.
This morning I dropped the transport board and cleaned up the front switches. The micros should be OK.
I've got an early model, a -2HD. These weren't sold to the consumer but to studios and record makers. I can imagine that a problem would prompt a call to a repair tech for service. That guy would probably have all he needed.
The owners manual I have, does not have a capstan motor control board schematic to it. Nor, a parts list. I open up an SM for a -Blll, on HiFi Engine, for that.
Now, there is a guy that started a four page thread, on Gear Slutz, that was rebuilding his capstan motor. Doing that, when it came to looking for a motor board schematic, there is none. A guy, out in California, wrote in to say that he used to work for Otari and had a schematic for the control board, he attached it to the post. I saved it to my computer.
The buzzing hasn't stopped but I could pass the schematic on if anyone could help me figure this 'buzzing' out.
And along with that, I started up the deck this morning, pressed play and no tape transport. ??? I turned it off, waited a minute, then turned it back on. With some persuasion, the reels were turning but it was jerky, like 60Hz. wall current. I stopped it, put it in FF and then Rew., and after that, reels were spinning normally. That would tell me it's just dirty. And it's why I cleaned in there.
While it's open, I could clearly hear that the noise is coming from the control board. I could unplug it, dismount it, and go over it for out of spec. components, if someone would tell me what to look for.
Any help, please. And yeah, that transport issue sure gave me a start!
Lu.