Yes they have A center tapped secondary that provides 700V for B+; Then the there is 6.3v 1a AC secondary for the filaments of the driver tubes and then they have 7.2V 2a filament winding that is rectified by a 4a 50 piv bridge into a pi filter for 5vdc for the 300b's. B+ is connected at the primary. The plate voltages would be fairly simple to figure mathemagectly but it takes me some time. There is not much more to the circuit.