This is a single tube transmitter with a "Type 47" Power Pentode. The schematic can be found in the 1936 Jones Handbook, on page 115.

The filament voltage is 2.5 and the plate voltage is 350.

A 6.3 volt bulb in series with the antenna is used for tuning,

The rcvr in an old Heathkit HR 1680.

And finally a shot of an OA2 regulator tube.