The 954 miniature all glass acorn valve is a pentode with a 6.3 Volt heater. This valve type dates back to 1935. Visual inspection shows the three grids within the anode cavity.

The normal 5 side pins are supplemented by pins top and bottom making seven contacts in all. For pin connections please see data sheet.

The small size of these valve enabled them to operate at VHF.

The valve is marked JRC954, the JRC marking being a US Government quality code.

The envelope is 19 mm in diameter and, including the base pins, is 41 mm tall.

 
Absolute Maximum Operating Conditions

Pentode	Vh	Ah	Va	Vs	Vg	mAa	mAs	ra	gm	μ
	6.3	0.15	250	100	-3.0	1.2	0.5	1.0M	11.0	1100

Thanks to Frank Philipse for supplying the above datasheet

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