The CV2130 specification is based on the Mullard QY3-125. It is an RF power tetrode with a maximum anode rating of 125 Watts dissipation. To keep within temperature limits forced air cooling is required above 50 MHz. Interestingly this valve is also rated for use as a class B modulator where a pair can generate 345 Watts of audio.
The anode is hung from the top cap.
The top of the anode is partially closed by a top ring with a small central hole.
The hard sintered glass base with B5F base pins.
The filament is helical and the grid is a cage of vertical wires with a thin helical wire running the length of the grid.
The wide glass tube envelope is 60 mm in diameter, and excluding the B5F base pins is 106 mm tall.
Reference: Data-sheet. Type CV2130 was first introduced in 1956.