The DEQ was introduced in 1923, and was intended to replace the Q and Qv. The construction is similar to the Q. The filament is a single wire running the length of the envelope and tensioned by a spring at the end opposite the anode and grid supports.

The anode and grid connections on the envelope pass to a shaped piece of glass rod that supports the electrodes. The grid helix is clearly visible in the picture above. A distinctive feature of the DEQ is the green band of paint around the centre of the envelope.

The DEQ is a very high impedance valve and its primary function was as a detector.

The thin glass tube envelope is 17 mm in diameter and, tip to tip measures 73 mm.

 
Absolute Maximum Operating Conditions

Triode	Vh	Ah
	3.0	0.2

This exhibit was last updated on 02 December 2007