This tube was designed by Kellogg for McCullough and was a detector-amplifier. It is a rare tube and was replaced by the 403. There is no known record of any receiver using the tube.
Literatura
Tube Lore (I) p. 33
-- Collector info (Sammler)
Babani, International Radio Tube Encyclopaedia
Taschenbuch zum Röhren-Codex 1948/49
402_McCullough: Fin Stewart
Fin Stewart
Just Qvigstad
402_McCullough: own collection
Peter den Boer † 2025
