[Info-vax] SBB power supplies failing slowly

[gah4]

On Monday, March 28, 2022 at 2:55:25 AM UTC-7, Jan-Erik Söderholm wrote:

(snip)

> PSUs are aging. The electrolytic capacitators are drying out. This will 
> make the voltages to become more unstable and causing intermitent 
> issues before going totaly "off". Quite normal, I'd say. 

It seems to me that this is true for everything.  I have replaced
capacitors in fluorescent lamp ballasts, though usually try to buy
new ones.  Computers are usually built with better ones, but some
things last about a year.  Digital TV converter boxes are some of
the worst in terms of capacitor life. 

> Some makes a buiness out of replacing old capacitors in power supplies 
> for TV sets and other home/kitchen appliences. I guess that is equially 
> possible in these PSUs. They are not too modern and should be fine to 
> work on without special soldering equipment.

It is nice to have a hot air soldering unit, though that might not do
everything that is needed today.  You need something fancier for
BGA chips, though.  

Otherwise, I would probably replace both primary and secondary
side capacitors, though I suspect less problems primary side.