The 12E14 is a 35 Watt anode dissipation beam tetrode designed for use as a control element within stabilised power supplies. This service places a heavy load on the cathode and the valve has a generous heater power.
The 12E1 is similar but has the anode brought out as a top cap.
The KB/FE identifies this valve as being made to specification K1001 or K1006, the B denotes qualification by a UK authority and the FE identifies the maker as STC, Oldway (Additional to Paignton factory 'F').
Through the holes in the anode can be seen the bright beam forming plate used to repel secondary electrons liberated by bombardment of the anode.
The inner grids pass flat across the cathode.
The valve also carries the CV8727 designation showing direct equivalence.
A close-up that reveals the control grid.
The wide glass tube envelope is 38 mm in diameter, and excluding the IO base pins is 81 mm tall.
Reference: Data-sheet. Type 12E14 was first introduced in 1961. See also1961 adverts.
