The CV2005 is a CV140 with tape leads welded to the pins.
Electrically it is a double signal diode, commercially this was the 6AL5, the valve the UK Government CV specification was based upon.
The two valves are completely separate flat structures separated by a plate screen. This clearly shows the signal usage, where it is important to keep RF isolation.
Mullard designed these diodes for vision and sound detection.
The KB/K identifies this valve as being made to specification K1001 or K1006, the B denotes qualification by a UK authority and the K identifies the maker as ETEL, Electronic Tubes, High Wycombe.
The crossed out CV140 clearly shows that the CV2005s were post processed to have the welded leads added.
The imperfections in the glass spoil the view of the inner structure.
The thin glass tube envelope is 18 mm in diameter, and excluding the B7G base pins is 47 mm tall.
References: Data-sheet & 1040. Type CV2005 was first introduced in 1953. See also1953 adverts.
