The CV173 is the UK government type number for the commercial EF55 pentode. This is physically the big brother of the EF50 with which it shares common base connections. The CV173 is a single ended RF pentode with very high mutual conductance and a sharp cut-off. It was designed for video frequency use, probably in RADAR service.

It is an early all glass constructed valve with equi-spaced pins and a spigot for location into the valveholder.

The current rating places it as a power valve but it is designated for amplifier service with a medium anode impedance.

The outer aluminium shield is 32 mm in diameter. The overall length excluding the B9G base pins, is 80 mm.

 
Pin Connections

B9G	1	2	3	4	5	6	7	8	9
	h	g2	a	g3	s	k	g1	s	h

 
Absolute Maximum Operating Conditions

Pentode	Vh	Ah	Va	Vs	Vg	mAa	mAs	ra	gm
	6.3	1.0	250	250	-4.5	40	5.5	55k	12.5

This exhibit was last updated on 07 January 2007