The CV315 (commercially the 4304CB) is a directly heated triode RF amplifier and oscillator. The specification is for a pair of matched valves. The maximum frequency of operation was 100 MHz. The prototypes were the DET22 & 4304CB.
The printed STC logo and the commercial Type designation of 4304CB. The 4 indicates a UK version of an American design - the 304CB.
The filament is a double helix that has the centre point joined to a support rod that is secured into the glass pinch.
The control grid has both supports welded to the strut that goes to the top cap.
The three side flanges on the anode. Within can be seen the form of the thoriated tungsten filament and control grid.
The balloon envelope is 64 mm in diameter and, excluding the B4 base pins, is 150 mm tall.
