The 12K7GT variable-mu screened pentode was designed for intermediate frequency amplifiers in superhet receivers where the stage gain was controlled by the application of negative bias on the grid that was derived from the received signal. It is high impedance valve allowing for a high Q in the tuned anode circuit.

See also 6K7.

The wide glass tube envelope is 28 mm in diameter and, excluding the IO base pins, is 67 mm tall.

 
Pin Connections

IO	1	2	3	4	5	6	7	8
	m	h	a	g2	g3	nc	h	k

 
Absolute Maximum Operating Conditions

Pentode	Vh	Ah	Va	Vs	Vg	mAa	mAs	ra	gm
	12.6	0.15	250	125	-3	10.5	2.6	0.6M	1.65

Thanks to Frank Philipse for supplying the above datasheet

This exhibit was last updated on 12 June 2007 {find valves by name}