[morzh]

I opened up and lubed the volume pot.
It is suposed to be 500K (no one expects it to be that), and it is about 1.5M.
The contact of wiper and the resistive band has improved after F5 application.

One thing I am not sure: it looks like the taper is linear and not log. I am not familiar if the log taper was used back then: even in Philco 20 the pot is wirewound and therefore is unlikely to be log taprer.
So is it linear? Anyone knows for sure?



Also, the power switch. Open, after 5-10 clicks going to 100 Ohm or so...

   

A narrow opening right between the copper dome and the rest of the case could be seen in this photo; I icould see some movement through this slit; I sprayed D5 into it, twice, and worked the switch.
It is now dow no 0.3-0.5 Ohm.
I will dry it and replace.