The CV1626 is a directly heated mercury vapour rectifier. The prototype was the RG1-240 The old GPO code is POVT168.
The KB/D identifies this valve as being made to specification K1001 or K1006, the B denotes qualification by a UK authority and the D identifies the maker as Mullard Radio Valve Co., Mitcham.
The shallow open cylinder anode is suspended from the top of the envelope. The filament is concealed inside the screen.
Looking through the base of the screen the filament can be seen as a coiled coil.
The anode and support.
The classic envelope is 45 mm in diameter and, excluding the B4 base pins, is 120 mm tall.
