[morzh]

No you do not have to worry about micas, and try not to desolder them at all. Leave them be. Rarely it is that a mica cap fails. I have yet to see it.

mmfd is a picofarad, pF. "m" in the old notation stood for what "u" (which is a poor replacement of Greek "Mu") stands today, "micro". "mm" is "micro-micro" which is "pico-" today, or 10^-12, one-trillionth.

Today "mF" would mean 1,000 uF (microFarads), that is "milliFarad", and this is confusing for many folks, so one has to discern between old and new notations.

So, for radios:

m - Micro, 10^-6F, a microFarad
mm - micro-micro, or today's "pico"

And, despite "nano" being popular today, many local folks frown on it, using "0.001mf" instead of "1nF".
All the same.


So, to recap the recap:

- worry about any paper cap, whether a tubular or in a backelite case. Replave 100%
- Electrolytics. Replace 100%.
- - do not worry about micas. Only replace if find one bad in the troubleshooting process. Good luck finding one.
- Check the resistors, replace as needed; 20% tolerance is good. And even more in many cases.