The ECH83 is a triode heptode frequency changer has the unusually low anode voltage of 12.6 Volts, the voltage of vehicle batteries. This valve was clearly designed for use in such an environment, Mullard describe it as being designed for use as a mixer in hybrid car radios.

See also EBF83, ECC86 and EF98.

The thin glass tube envelope is 20 mm in diameter and excluding the B9A base pins the valve is 59 mm tall.

 
Pin Connections

B9A	1	2	3	4	5	6	7	8	9
	g2,g4	g1	k,g5,s	h	h	ah	g3	at	gt

 
Absolute Maximum Operating Conditions

Heptode	Vh	Ah	Va	Vs	mAa	mAs	ra	gm
	6.3	0.3	12.6	12.6	0.15	0.35	1.5M	0.2

Triode	Va	mAa
	12.6	0.75

Thanks to Frank Philipse for supplying the above datasheet

This exhibit was last updated on 06 July 2007 {find valves by name}