Was having issues staying powered on. Discovered the 20year old slow burn fuse was on it's last leg, connected but not actually attached. Replaced the fuse, device powered on. The original issue was the device would power on then just fade to 0 power after 10-20 seconds. Left device powered on with new fuse, came back 30min later to see if it was still powered on. Accidentally touched the - terminal of the full bridge to the what appears to be Isolated ground chassis (side of the multi-meter lead brushed against it, I should have taped over it or had shorter leads, lesson learned). Big spark, fuse blew. New fuse, insta pop (***Edit***: upon inspection they sent me a 50ma fuse instead of 5A ***Edit***). Rectifier seems to test green when doing diode tests between it and the L/N AC, everything seems to only be able to move in the correct direction, no shorts. Thinking hopefully the DC/DC switching IC may have gotten damaged, but not sure if that is going to be a red herring because I'm still a bit new at this. Anyone have any thoughts? Suggestions? New fuses set to arrive next week, 10 this time.
Schematic is on page 46/47 of the PDF