[beery]

Hi Doug,
Going back to the problem of the valve sockets...
The guy who "restored" the set didn't tell me that he had soldered the valves in. It was a nasty thing to do, but the difficulty of accessing the sound chassis may explain why he did it.
Anyway, that is by the by.

If the valve sockets have suffered from de-zincification then the contacts will have lost their springiness and will be fatigued. If that is the case then they will need to be replaced. I've found that EMI valve sockets have an unusually large spacing between the mounting points, which is a pain when trying to find replacements.

If the contacts are simply tarnished then they can be cleaned up. I'm currently working on a prewar set with paxolin Mazda octal sockets (slightly different from American octal). All the postwar Mazda octal sockets I have seen are moulded Bakelite, so I couldn't use them. My only course of action was to clean the contacts. I used a drill bit with the same diameter of the valve pins. I spread the blunt end of the drill with T-CUT (original formula) and inserted the bit into a contact hole, moving it in and out and twisting it a few times. Then I cleaned the T-CUT off with a paper towel soaked in IPA. I did this for each contact of each valve socket and the results were very good. This method might work for your set.

Cheers
Andy