The 12C8 valve was designed for Radio/Radar reception. The most usual multiple valve with a common cathode is the double diode triode so this valve with the pentode amplifier could be used as a final IF plus detectors or detectors and first audio amplifier.

For signal screening the control grid of the pentode is brought to the top cap.

The valve is identical to the 6B8 except that it was to operate from 12.6 volt for the heaters for use in vehicles where the 12.6 volts were readily available from batteries.

The thin metal tube envelope is 25 mm in diameter and, excluding the IO base pins, is 62 mm tall.

 
Pin Connections

IO	1	2	3	4	5	6	7	8	tc
	m	h	a	ad(2)	ad(1)	g2	h	k	g1

 
Absolute Maximum Operating Conditions

Pentode	Vh	Ah	Va	Vs	Vg	mAa	mAs	ra	gm
	12.6	0.15	250	125	-3	9	2.3	0.6M	1.12

Thanks to Frank Philipse for supplying the above datasheet

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