The X130 is a 100 watt dissipation experimental tetrode. This identification is approximate as there were several variations (X129, X131, X132, X134 and X135) made in early 1944. This example has no base and the base seals are uranium glass. The X130 group were supposed to be made from 100T anodes and filaments. I believe these became the 4-125A.

Length = 5.75" Diameter = 2.50"
Max voltage =
Max current =
Fil voltage = 5
Fil current = 6.2 amps         GOTO INDEX