[R-390] To swap or not to swap those aging "reddish" rectangular mica caps

[jkharvie]

Guided discovery continues as I make progress on the RF sub chassis.I received C327 replacement for "high Q" 100pf, 1,000 volt mica capacitor to install on the primary output of T207.I received group input that the green mica mold caps provides acceptable operational service with very low failure rates, and the "reddish" color caps are older generation and appear to have a statistically higher failure rate, and should be replaced with new high q mica caps.Two examples in the receiver, (1) with all reddish mica capacitors, and (2) 1 out of 2 reddish capacitors.My course of action is to keep the green, replace the reddish capacitors.
Or does the group make the case that while the patient out and ready for surgery to replace both capacitors while opportunity is good?
Thanks in advance to your vast repository of deep informed knowledge as I work my first end to end refurbishment on this magnificent receiver.Happy 4th of July, celebrate independence day.
John N3JKE







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