> -----Original Message----- > From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Richard > Loken > Sent: 11 December 2015 16:45 > To: General Discussion: On-Topic and Off-Topic Posts > Cc: gene...@classiccmp.org > Subject: Re: VAX 4000-500 PSU Overload? > > ... > > My doctor once said to me that all problems in the head involve teeth and I > can safely make a similar exageration: > > All electronic failures involve capacitors > > And this becomes (most repulsively) even more true when switch mode > power supplies are involved. Keeping that in mind will usually help with > diagnosis. >
Well, I have the exception that proves the rule. My H7864 PSU (from an rtVAX 1000, same PSU as MicroVAX II) had a switching transistor and resistor fail, no cap failures.... :-) Regards Rob