The CV309 is the CV1510 with plated pins. The commercial version of these valves is the QV04-7 single beam tetrode.
This design uses an early all glass envelope and base. The output is modest and the dissipation high in relation to the output. The efficiency as a Class C RF amplifier was 45% which is low for a Class C stage and this probably reflects the difficulty of working at 150 MHz at the time.
The side flanges of the anode connect to the supports and are placed in the centre of the working face facing the cathode.
The components above the base. The heater wire is coiled before being coated in ceramic insulation.
The wide glass tube envelope is 32 mm in diameter, and excluding the B9G base pins is 58 mm tall.
References: Data-sheet & 1040. Type CV309 was first introduced in 1947.