The DE2LF is a dull emitter triode dating from 1925. It was designed for LF amplification and had a lower anode impedance than the DE2HF released at the same time.. The valves from M-OV of this period used carbonized thoriated tungsten filaments. The carbonizing reduced the effects of any residual gasses in poisoning the thoriated filament.

See also DE2HF.

The BBC logo is present on this valve illustrating the fact that this valve is an original 1920s valve and not a later replacement.

The balloon envelope is 32 mm in diameter and, excluding the B4 base pins, is 73 mm tall.

 
Absolute Maximum Operating Conditions

Triode	Vh	Ah	Va	Vg	mAa
	2.0	0.12	45	-	0.5

This exhibit was last updated on 02 December 2007