This valve is a dual transmitting tetrode. It has not been possible to locate original data for this valve. It arrived as part of a pair both additionally marked on the envelope as 832A. The operating conditions given may be slightly inaccurate.

The design is of the American type with two separate valves sealed into the single element. The oval cylinder anodes enclose the beam plates, grids and heater cathode assembly. This type of construction usually required external capacitors to neutralise parasitic oscillations. These capacitors normally taking the form of vertical wires alongside the envelope.

This valve was obsolete by the start of the 1960s replaced by the QQV03-20 orQQV06-40A varieties.

The wide glass tube envelope is 50 mm in diameter and, excluding the B7A base pins, is 51 mm tall.

 
Pin Connections

B7A	1	2	3	4	5	6	7
	k bp	htap	g1(1)	h	h	g1(2)	g2

 
Absolute Maximum Operating Conditions

Tetrode	Vh	Ah	Va	Vs	Vg	mAa	mAs	mAg	Pdriv	Pout	Pdiss	freq	f.max
	6.3	1.6	400	145	-45	170	17	4.5	0.23W	44	20W	125	200

Thanks to Frank Philipse for supplying the above datasheet

This exhibit was last updated on 10 June 2007 {find valves by name}