[Chuck Schwark]

Also make sure you re-build ALL the bakelite block condensers, not just the audio coupling. Very leaky B+ bypass caps can drag down the B+ and screen voltages. Resistors ALWAYS go up in value and they can lower voltages too. Check and replace ALL resistors as needed, like Ron says.

Also check the continuity of the "volume" control (dual pot unit), if you have the EARLY version (non-AVC) chassis. One section controls the grid bias (via cathodes) of two for the RF tubes. If open or defective it possibly will unbalance voltages.