Old Caps

[billsterl]

My wifes father has alot of old parts he is willing to give. What is the deal with old caps do the sealed types stay good over time. Which types dry out or become unusable when they get old. He has alot of different types silver mica and alot of ceramic discs as well as some orange drops. He says he has a cap tester how does that work and what are you looking for?

[doctord02]

Within reason, all of the caps you mentioned should be OK. Ceramic, Orange Drops, Mica, Mylar, PolyProp, etc..

The caps to avoid are old electrolytic (power supply filter) caps. Anything over ten years old is highly suspect.

Cap testers generally wont tell much about electrolytics, 'cause most meters dont test them at operating voltage, unless he's got some more sophisticated testing gear.

[Allynmey]

I use a Sencor LC75 to test older electrolytics. If they are 5+ years old, I hit them at full voltage. It tests to 600V

Allyn

[billsterl]

If someone had a bunch of old caps would you willing to test them for a fee? How long does it take to test them.Is it worth doing- I guess it depends what they are and what they are worth.