The 12SA7 is a pentagrid converter for use as a mixer oscillator in superhet receivers. The design is quoted by RCA as optimised to increase stability.

The RCA brand. RCA introduced the glass disc sealed into metal envelope designs in 1935.

The thin metal tube envelope is 25 mm in diameter, and excluding the IO base pins is 51 mm tall.

 
Pin Connections

IO	1	2	3	4	5	6	7	8
	g5	h	a	g2,g4	g1	k	h	g3

 
Absolute Maximum Operating Conditions

Heptode	Vh	Ah	Va	Vs	Vg	mAa	ra
	12.6	0.15	300	100	-0	14.0	1.0M

Thanks to Frank Philipse for supplying the above datasheet

This exhibit was last updated on 24 August 2008 {find valves by name}