Sensibly equivalent¶ to:
The 12AU7 is a double triode and this exhibit the 12AU7A is a special quality version of that design specification. Probably a rugged version for operation in a vibrating environment.
An amplification factor of 17 is quoted, the same as the 12AU7.
The thin glass tube envelope is 20 mm in diameter and the length excluding the B9A base pins, is 46 mm.
Reference: Data-sheet. Type 12AU7A was first introduced in 1956.
Absolute Maximum Operating Conditions¶
Updated February 23, 2013. shape:thin.glass.tube construction:all.glass type:double.triode age:1950.1960 base:b9a heater:6.3v pins:9 pin:1.a pin:2.g1 pin:3.k pin:4.h pin:5.h pin:6.a pin:7.g1 pin:8.k pin:9.hct