[AMRadio] Help with silver mica marking

Michael Mertes fnerks1 at yahoo.com
Fri Sep 14 16:51:21 EDT 2007

Hello Rick, 

The J after the multiplier is often specific to the
manufacturer. The same with the numbers following it.
Usually the letter has to do with tolerance or
temperature coefficence. The numbers following the J
don't appear to be related to the voltage.

Your mileage may vary.


--- Rick Brashear <rickbras at airmail.net> wrote:

> I have some 220 pf silver mica capacitors with the
> following markings:
> CM05FD
> 221J03
> I know the 221 means 22 X 10, but is the J the
> tolerance or voltage rating?
> Been too long...
> Thanks for all help..
> Rick/K5IAR
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