Here is a before and after shot of an ongoing project restoring a Fisher 500c. The original 0.047uf/600v and 0.047uf/400v coupling caps were removed and replaced with 0.1uf/600v Vishay polypropylene “Orange Drops”. The grid resistors which were 320k ohms were removed and 200k ohm metal film resistors were put in its place. Next up for the restoration will be installing “fusistors” on the cathode end of the 7591 output tubes. These will act as a testing point for bias current.
