The EL38 was designed as a television line output stage valve. In the early days of CRT based television the tubes could have been either electrostatic or magnetic deflection. The EHT supplies were probably derived from special mains transformers and ran at about 10 - 14 kV. Thus the line output valve was not as heavily stressed as later types had to be.

The EL38 was designed to withstand a positive anode surge of 8,000 Volts and in addition to the 25 Watt anode dissipation the screen grid was wound to withstand a dissipation of 18 Watts. The cathode is oval, and the ceramic insulators are clearly visible.

The classic envelope is 41 mm in diameter and, excluding the IO base pins, is 115 mm tall.

 
Pin Connections

IO	1	2	3	4	5	6	7	8	tc
	g3	h	-	g2	g1	-	h	k	a

 
Absolute Maximum Operating Conditions

Pentode	Vh	Ah	Va	Vs	mAa	mAs	Pdiss
	6.3	1.4	300	250	64	18	25,

Thanks to Frank Philipse for supplying the above datasheet

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This exhibit was last updated on 03 June 2007 {find valves by name}