Sensibly equivalent¶ to:
The CV491 is a double triode with separate cathodes. An amplification factor of 17 is quoted. The prototype was the 12AU7.
We were surprised at the very low CV number, suggesting availability during WWII but we know that B9A based valves were not made in the UK until the late 1940s. The CV numbers were not issued from one.
The thin glass tube envelope is 19 mm in diameter and, excluding the B9A base pins, is 48 mm tall.
References: Data-sheet & 1040. Type CV491 was first introduced in 1946.
Absolute Maximum Operating Conditions¶
Updated October 07, 2013. shape:thin.glass.tube construction:all.glass type:double.triode age:1940.1950 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