[sdiy] Electrolytic capacitor life

[Neil Johnson]

Hi Dave,

> A few years back I got many unused electro caps amongst other things
> from a clear-out of a broadcast maintenance department that was
> closing-down. I have heard that electro caps "dry out" over time. These
> particular caps are probably around 10 - 20 years old.
>
> Are they any good? Recently I found and rejected at least one cap that
> measured well below its rated capacity.

I think a lot depends on the environment the caps were stored in?
Caps in a warm mixing desk, foe example, will dry out over the years.
But if stored in a bag or box out of the way then its possible that
they'll be OK.  Only way to be sure is measure them, give them a long
soak with a few volts to tickle the electrolyte (if any) back into
action, and measure again.

That said, modern caps are rather better than their older cousins, so
unless you *specifically* need the old caps I'd go with fresh ones and
reset the age-clock.

Cheers,
Neil (planning a desk recap...)
-- 
http://www.njohnson.co.uk