DEC (digital) VAX 4000 Model 300 Power Supply (H7874) Issues and Replacement - Part 1

Frist investigations on the PSU issue of the VAX 4000 Model 300
Links to a person with similar problems and his solution:
aaronsplace.co.uk/blog/2018-0...
aaronsplace.co.uk/blog/2020-0...
Chapters:
0:00 Intro
0:34 A spare H7874 PSU
2:09 Open the PSU
2:24 A visual inspection
3:43 Back at the VAX 4000/300
4:14 Replace the PSU and turn it on
4:38 A second investigation

[@BiggRanger]

I love these systems, I have several MicroVAX and VAXStation 3100's still working, as well as AlphaServers and AlphaStations and a PDP11/23

[@DECcomputers]

MicroVAX 3100 is a nice machine. I have a VAXserver 3100, which is basically a MicroVAX 3100 with another ROM, but I don't know if it working, it is a projekt for a further video. I've never had a deep look into Alpha, however I think about to expand my collection with an Alpha maschine.