Sensibly equivalent¶ to:
The 14A7 is an early all glass construction pentode. The central spigot hides the evacuation seal. The 7A7 is identical except for having a 6.3 Volt heater.
This variable μ valve was designed for high gain signal amplification, at RF and IF in broadcast receivers.
Electrically the 7A7 and 14A7 are similar to the IO based 6K7GT and 6SK7GT.
The dome carries the 14A7 Type designation and the alternate 12B7.
The wide glass tube envelope is 29 mm in diameter and, excluding the B8B base pins, is 57 mm tall.
References: Datasheet & 4059. Type 14A7 was first introduced in 1940.
Absolute Maximum Operating Conditions¶
Updated August 24, 2015. shape:wide.glass.tube construction:all.glass type:pentode age:1940.1950 base:b8b heater:12.6v pins:8 pin:1.h pin:2.a pin:3.g2 pin:4.g3 pin:5.s pin:6.g1 pin:7.k pin:8.h