[Arran]

The Bakelite block condensers have paper condensers inside of them, they were commonly used in Philco sets from about 1930 through 1936 and were slowly phased out in favor of the more usual tubular types till just before the war. So the newest ones are now over 70 years old and pretty much have to be replaced. The Bakelite blocks also act as terminal strips so they pretty much have to be cleaned out and restuffed with new condensers, or replaced with a terminal strip, sort of six of one and half a dozen of the other. Some on here are very good at restuffing them, they can undo the screw, flip the block over, remove the old condenser, and replace with a new one, all without disconnecting most of the wires.
While you are at it I would check all of the old carbon composition resistors, any that are more then 20% out, replace them.
Regards
Arran