The C144 was introduced by Marconi in 1954. It was described as a push-pull beam tetrode with an indirectly heated cathode, suitable for use as a RF power amplifier at up to 200 MHz. Forced air cooling was recommended to keep the bulb below 175 °C
The mutual conductance figure of 9.00 mA/V was given with an anode current of 60 mA. The heater is in two sections so that it can be run from 12.6 or 6.3 Volts.
In use the anode current would by typically 160 mA and the valve was designed for use as a class C amplifier.
The wide glass tube envelope is 48 mm in diameter and, excluding the B7A base pins, is 92 mm tall. The maximum diameter of the retaining ridge is 55 mm diameter.
Reference: Datasheet. Type C144 was first introduced in 1954.
Absolute Maximum Operating Conditions¶
Updated December11, 2015. shape:wide.glass.tube construction:all.glass type:double.beam.tetrode age:1950.1960 base:b7a heater:6.3v pins:7 pin:1.h pin:2.g1(2) pin:3.g2 pin:4.k.bp pin:5.hct pin:6.g1(1) pin:7.h pin:tc.a pin:tc.a