Paul P REMOVE paul @ REMOVE ppinyot . REMOVEcom wrote:

I discovered that any of the flat "Domino" style caps with Micamold stamped
on them are best replaced.

Sheesh, and we still have boxes of the things brand new at work...
-s-cott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

"Scott Dorsey" wrote in message
...
Paul P REMOVE paul @ REMOVE ppinyot . REMOVEcom wrote:

I discovered that any of the flat "Domino" style caps with
Micamold stamped
on them are best replaced.

Sheesh, and we still have boxes of the things brand new at
work...
-s-cott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

I would test them before use. These are mostly stacks of
mica dielectric and aluminum foil electrodes rather than
plated "silver mica" types. Mostly, they were use for high
voltage transmitter circuits. They do not have the stability
and very low leakage of the plated type but were useful for
HV bypass use. I think they may suffer from the same
problems with degradation of the bakelite shell that other
caps seem to have. Also, the fact is that most of these caps
are getting to be very old.


--
---
Richard Knoppow
Los Angeles, CA, USA

"Richard Knoppow" wrote in message
...

"Scott Dorsey" wrote in message
...
Paul P REMOVE paul @ REMOVE ppinyot . REMOVEcom wrote:

I discovered that any of the flat "Domino" style caps with
Micamold stamped
on them are best replaced.

Sheesh, and we still have boxes of the things brand new at
work...
-s-cott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

I would test them before use.

[snip]

Testing actual old mica caps before use is good advice, but there's no need
to test anything above .001uf branded "Micamold". The notorious Micamold
was a paper cap in a mica type domino case. The values typically run in the
paper cap area, say .01 or .02 uf at 600V.

I'm sure I've also seen tubular Micamold caps. The tubular Micamolds seem
less disingenuous but are no more reliable.

Frank Dresser