Mysterious (possibly original? Cornell Dubilier Beaver) capacitor not in schematics

[Madeline12]

Originally Posted by Phil

Actually the only capacitors you will see today are "dry" according to the terminology of the 1940's-50's.
From Wikipedia: He introduced a separated second foil to contact the electrolyte adjacent to the anode foil instead of using the electrolyte-filled container as the capacitor's cathode. The stacked second foil got its own terminal additional to the anode terminal and the container no longer had an electrical function. This type of electrolytic capacitor combined with a liquid or gel-like electrolyte of a non-aqueous nature, which is therefore dry in the sense of having a very low water content, became known as the "dry" type of electrolytic capacitor.[14]

I would definitely replace it. 4.7 mfd would be fine. It is a cathode bypass. It's purpose is to allow the signal to bypass the cathode resistor, which provides at least part of the bias for the horizontal output tube. It's value isn't critical. The 12 mfd may be factory or a later replacement.

Sounds great, will do!