Peavey Valveking blows fuses

[msclford]

I also posted this over at the peavey.com forum, but you guys have been helpful in the past so I thought I would see what you thought. I was using an audio probe to test a pedal I had built the other day when my Valveking 112 suddenly shut off. I hadn't grounded the probe and I'm assuming that is what caused the fuse to blow.

I have been troubleshooting on the amp and have narrowed the problem down to the high voltage power supply. I started by removing all of the tubes, and the fuse still blew when I powered up the amp. If I unplug the PT secondary wires, the fuse does NOT blow. If I connect all of the secondary wires besides the high voltage (red) wires, the fuse does NOT blow. If I connect the high voltage (red) PT secondary wires, the fuse DOES blow. The fuse blows with the standby switch off, so the issue seems like it has to be with the PT, the rectifier diodes, the filter caps, or with something that is connected to the PLATE voltage wiring.

My questions are:
(1) Does my troubleshooting rule out the power transformer as the source of the problem?
(2) Should I just replace the filter caps and recto diodes and go from there?
(3) Will any 1n4007 diodes work?
(4) Where can I even get decent replacement parts for this thing?

[msclford]

It seems like this might actually be a problem with the output tranny. I disconnected the OT primary wires and the fuse did not blow. I replaced the original with a Weber unit (WOT45HHR as seen on this wiki wiki about two months ago.

[Jazz P Bass]

Try to measure any resistance from the OPT wires to the case.
If it is shorted to case, it's bad.
Or check primary to secondary.
No shorts.

[msclford]

Enzo over at the Peavey forum helped me narrow it down to a flyback diode. A good cheap fix.