CW-1819

Tyne page 289-291: The experimental Type I tube was the forerunner of the Western Electric tube 212A, rated at 250 watts. Size about 13 5/8 inches high, 3 5/8 in diameter. Used as oscillator or modulator. Filament current 6.24 amperes at 12.5 to 14 volts. Anode 1500 volts for the current of 100-150 milliamperes - with an amplification factor of about 16 at an internal anode impedance of 2000 ohms. Assigned as CW-1819 by the Navy and VT-6 by the Signal Corps.

The 219A was the counterpart for the 212A as a rectifier, starting commercially in 1923 and we assume therefore that the 212A started in the same year. The 212A was replaced in 1924 by the 212D with a new filament for not having to classify for a filament resistance - and that tube lasted - inclusive the counterpart 219D from 1926 into the 1930s.