Years ago I was troubleshooting an old SuperMicro beast that was running a newspaper printing press. It kept shutting down randomly but if I hit the power button it would come up. Then randomly go down again minutes or an hour later.
I spent many hours testing and swapping modules in and out of this thing from a working machine and at one point it would only power up if the front box that contained the power switch module and CDROM/floppy were out of the enclosure and separate on the bench (but still connected to the motherboard by an data/power cables). If I got a long screwdriver and earthed this front box to the main enclosure the machine would go down immediately. Power switch itself tested fine with a meter but I found there was a hidden reset swtich that wasn't in use so I desoldered and swapped them over. All problems went away and the customer practically carried me at shoulder height around the press hall. -- adrian/witchy Owner of Binary Dinosaurs, the UK's biggest home computer collection? t: @binarydinosaurs f: facebook.com/binarydinosaurs w: www.binarydinosaurs.co.uk ---------- Forwarded message ---------- From: allison via cctalk <[email protected]> Date: 27 March 2018 at 13:32 Subject: Re: RL02 Question To: Aaron Jackson <[email protected]>, "General Discussion: On-Topic and Off-Topic Posts" <[email protected]> > Long short story. I got my RL02 directly through DEC while I was a > engineer there.It was a pile of parts in the back lab. The story was it was pulled > from a customersite as FS could not make it work at install. Seems despite being new > just about everything that could be swapped apparently was and no one could get it > to spin up. So I made a deal if I get it working its mine (ok, to be part of > the 11/23 in my office, which later would become mine). After assembling it and > testing it sure enough it didn't spin and would turn slowly for a few moments and quit. > Drag out the meter and start testing voltages. I found the motor starting > cap (known new) had odd voltages. A bit of ohming out later it was the crimped > faston connector at the end of the power line going to the capacitor. What > was wrong was crimped but the wire was never stripped so there was no connection. > The only thing never swapped was the power wiring harness. The pile of swapped > boards and even heads was impressive. I got the drive and word got around > that it was me that solved the riddle. I troubleshot the problem, and > didn't swap it to death.
