06-14-2013, 08:10 PM
Ceramic caps did not see widespread use until WW2 where they were first used in military equipment. After the war they began to show up in consumer electronics and became very common in the 1950s.
Regular stacked foil mica caps were common up into the 1950's when they were replaced by the modern dipped silver micas and ceramics. Except for special power RF versions (Unelco's) regular stacked mica caps are no longer made.
In their early "postage stamp" varieties, regular micas have brown or tan plastic cases while silver micas have red cases, so it is easy to tell the difference. All presently available epoxy dipped types are now silver mica construction, which involves depositing a thin coating of silver conductor directly on the mica dielectric.
Regular stacked foil mica caps were common up into the 1950's when they were replaced by the modern dipped silver micas and ceramics. Except for special power RF versions (Unelco's) regular stacked mica caps are no longer made.
In their early "postage stamp" varieties, regular micas have brown or tan plastic cases while silver micas have red cases, so it is easy to tell the difference. All presently available epoxy dipped types are now silver mica construction, which involves depositing a thin coating of silver conductor directly on the mica dielectric.
