21 May
2012
21 May
'12
9:07 a.m.
I received a new (to me) MicroPDP11/23 that I was
fiddling about with over
the weekend. After testing out the supply voltages, and
then putting the
system together enough to get serial out of it, there was a pop, a whoosh
and a rather exciting ejected ?> plume of smoke from one of the upper fans.
These seem to blow/burst often. I believe the cap is there only to limit RFI
emissions, so you can leave it out safely. The power supply should run fine
without it. If you do need to replace it, I wouldn't replace it with the
exact same type, but with a later cap less prone to blow. Any 250V 220nF cap
should do just fine.
Camiel.