The ECL82 is described by Mullard as an audio triode plus output pentode. We also have data from Brimar, in that the valve is described as a triode plus beam tetrode. The Mullard version will use the pentode configuration.

The triode section has a amplification factor of 70, and this valve was much used in record players with crystal pickups. The latter had a relatively high output and when coupled with the single ended pentode output stage made effectively a single valve design. Only a rectifier was required to complete the line-up. In the similar PCL82 form with 300 mA heaters this valve was a most popular choice for the audio stages of domestic television receivers.

The thin glass tube envelope is 20 mm in diameter and excluding the B9A base pins the valve is 68 mm long.

References: Datasheet & ¹⁰⁴⁰. Type ECL82 was first introduced^¶ in 1956.

 
Pin Connections

B9A	1	2	3	4	5	6	7	8	9
	g1(t)	k,g3,S	g1	h	h	a	g2	k(t)	a(t)

 
Absolute Maximum Operating Conditions^¶

Tetrode	Vh	Ah	Va	Vs	Vg	mAa	gm
	6.3	0.78	200	200	-16	35	6.4

Triode	Va	mAa	gm
	100	3.5	2.5

Thanks to Frank Philipse for supplying the above PDF datasheet

More