wh3016
Experienced Member
I have continuity for both AC and DC LO the connector on the PSU all the way to the backplane.Yes. It could be a reason for it not working. You have pullups on the M930. That is why they are high in the backplane. You somehow need to figure out where those signals is cut.
DEC used purple for DC LO and yellow for AC LO. Check the continuity from the PSU for those wires.
It can be that the backplane somehow is modified. It is hard to tell.
Looking back, I only had one of the M930’s plugged in to the backplane. Perhaps I’ll take another look and see if having both unibus slots makes a difference.