Old capacitors

[Eric Barbour]

>       I know that electrolytic caps deteriorate over time (time in this instance is 
>about 27 years); what about ceramic disc and plastic film types?

NOTHING goes bad with age like electrolytics. I have repaired numerous
antique radios,
many over 60 years old; and ALWAYS end up replacing electrolytic filter
caps. Ceramic
and film caps (and even most primitive paper caps) very rarely go bad.
It's even
unusual to see bad tubes in these radios. 

The same goes for old hi-fi amps and preamps from the 50s and 60s--bad
filter caps,
everything else usually OK.....

-- 
Eric Barbour
Svetlana Electron Devices
Portola Valley CA USA