Sensibly equivalent¶ to:
Here we have the special version of the 12C8 that was designated VT-153. The 12C8 valve was designed for Radio/Radar reception and was issued in the late 1930's. The most usual multiple valve with a common cathode is the double diode triode. With a vari-μ pentode and double diode it gave the set designer flexibility to use this valve as final IF stage, AGC rectifier and detector or Detectors and first audio voltage amplifier. The standard American Government procurement code for the 12C8 is VT-169.
For signal screening the control grid of the pentode is brought to the top cap.
The valve is identical to the 6B8 except that it was to operate from 12.6 volt for the heaters for use in vehicles where the 12.6 volts were readily available from batteries.
The thin metal tube envelope is 25 mm in diameter and, excluding the IO base pins, is 62 mm tall.
References: Datasheet, 1040 & 1043.
Absolute Maximum Operating Conditions¶
Updated October 02, 2015. shape:thin.metal.tube construction:glass.disc type:double.diode.pentode age:1930.1940 base:io heater:12.6v pins:8 pin:1.m pin:2.h pin:3.a pin:4.a(d2) pin:5.a(d1) pin:6.g2 pin:7.h pin:8.k pin:tc.g1