[TV MAN]

I vote for the socket contacts too. Have you tried a different 6v6? Could be a solder connection - it is easy to miss getting something soldered good if there is a lot of wires, or if there is oxidation on the new (or old) compenent, sometimes it wont solder good. Found this on other electronics before. I really dont think swapping parts, other than tubes is the answer. You may create more problems, and make it even harder to repair. You need to make some checks. Make sure you havent created a short with a ball of solder, bridged socket contact, etc. Do you have a schematic? Do you have a signal generator? You could have an open Rf/osc or IF coil. Check those. Sometimes an old radio isnt put into the attic for just one problem - often they start having small problems, then when things get to the point it no longer works, or the owner cant stand it anymore, it gets put up (or thrown away), so it may have several problems that will need worked through, plus any problems that happen while sitting.