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Early Electronic Television

DuMont 144-9-T/14AP4

The original version of this tube, the 144-9-T, used 4000 volts on the anode, and was introduced in 1938. In 1939 the 14AP4 was introduced, which had an "accelerator" element, allowing a total of 8000 volts of anode voltage. After World War Two, DuMont introduced the K1003P4, which was designed as a replacement for the earlier tubes.

How Television Tubes are Made - Radio News, July 1938

 Here are some more detailed photos

Courtesy of Mike Schultz

The gun attached to the stem

RF heating of the getter

Early Television Museum

5396 Franklin St., Hilliard, OH 43026

(614) 771-0510