[RodB]

Best to use the one from the library on this site, then when you refer to part 30 we know which part you are referring to. Of course any radio not a Philco you would have to provide a schematic or link to a schematic.

These tubes are local tubes and the base is kind of a shield. The center post of the tube socket should be wired to chassis ground for the shield to work. If you look at the second XXL in the schematic, you can see a dashed line just inside the tube, it is connected to ground. That's the center post. You will see components connected to the center post because it is a convenient ground terminal.

So you can see how Important it is to identify parts with the schematic, especially when you have multiple parts of the same value. When removing a part, connect a jumper wire with gator clips to each terminal so you have a reference where the new one goes.