[Info-vax] SBB power supplies failing slowly

[Scott Dorsey]

gah4  <gah4 at u.washington.edu> wrote:
>
>Otherwise, I would probably replace both primary and secondary
>side capacitors, though I suspect less problems primary side.

In the case of that specific supply, the problem is that the two big banks
of secondary side capacitors run hot because of all the high frequency 
ripple.  So they fail earlier than they might.

The filter stuff on the primary side seems to last much longer, except for
the kickstar cap and I don't know why that one seems to fail so often.

NOW... I will say that I have only experience with these supplies used on
120V and if you run them on 240V then the two big stab-in capacitors on
the high voltage input will have twice as much voltage across them and this
may shorten their life.  So you may wish to replace those pre-emptively if
you are in a 240V country.  I have never seen one fail in the US.
--scott
-- 
"C'est un Nagra. C'est suisse, et tres, tres precis."