Sensibly equivalent¶ to:
The 7R7 is a screened pentode and double diode. This is the classic valve design for AGC rectification, signal detection and first audio amplifier. The alternate use for the pentode is as an IF amplifier as it is of a semi variable-μ type.
Made in England by STC under the Brimar brand name.
The wide glass tube envelope is 28 mm in diameter, and excluding the B8B base pins is 56 mm tall.
References: Datasheet & 1040. Type 7R7 was first introduced in 1942.
Absolute Maximum Operating Conditions¶
Updated January 11, 2017. shape:wide.glass.tube construction:all.glass type:double.diode.pentode age:1940.1950 base:b8b heater:6.3v pins:8 pin:1.h pin:2.a pin:3.a(d2) pin:4.a(d1) pin:5.g2 pin:6.g1 pin:7.k pin:8.h