[Boatanchors] Calling Radio and TVl techs from days gone by

[L L bahr]

What happens is the caps are not well sealed and over time moisture gets inside them.  Also, the paper has acid in it and when the moisture mixes with the acid, the cap leaks and also can act as a battery.  (If you put an ohm meter across them in a low DC voltage scale, you can sometimes read a voltage they are producing.  I'm talking about a cap outside a circuit all by it's lonesome.)  Some of the old postage stamp caps were not micas but paper caps and the same thing happens with them.  Personally I would never ever use old paper caps when restoring a radio.  No way.  Good new caps are inexpensive and if I'm going to put labor into the restoration, I am not going to replace old bad caps with other old bad caps. Old caps that have never been used are not immune to the above process.
Lee, w0vt



----- Original Message -----
From: "Rob Atkinson" <ranchorobbo at gmail.com>
To: "John King" <k5pgw at yahoo.com>
Cc: "Boat Anchors List" <boatanchors at mailman.qth.net>
Sent: Friday, May 9, 2014 8:59:15 PM
Subject: Re: [Boatanchors] Calling Radio and TVl techs from days gone by

The plastic encased paper caps I'm told can be leaky.  But that's if
they have been in a circuit.  Don't know if NOS makes a difference or
not.

Rob
K5UJ