The LS5A from M-OV was a dull emitter valve designed for audio amplification.

The LS5A was introduced in 1924 with a metal base skirt. The LS5A improved on the original LS5 by having a lower impedance, which in turn allowed a greater output power to be delivered by the valve.

This exhibit is a later version and has a Bakelite base that also hides the evacuation seal.

From the top of the envelope can be seen the cross section of the anode cavity and also the etched lettering.

The Osram branding took the form of this paper label.

The delicate spring for the filament can be seen but sadly the inverted 'V' filament is missing.

The balloon envelope is 57 mm in diameter and, excluding the B4 base pins, is 110 mm tall.

 
Absolute Maximum Operating Conditions

Triode	Vh	Ah	Va	Vg	mAa	ra	gm	Pdiss
	4.5	0.8	60-400	-20	-	2750	0.91	10W

Thanks to Frank Philipse for supplying the above datasheet

More

This exhibit was last updated on 02 December 2007 {find valves by name}