22.Nov.1935 : Wireless World (The), London (WW, 79)
Base
British-7-Pin, old (M7A) (Codex=N)
Usada en
Radio/TV-reception etc.
Filamento
Vf 40 Volt / If 0.2 Ampere
Literatura
History of the British Radio Valve to 1940 p. 1444 & 189
Babani, International Radio Tube Encyclopaedia p. 16 & 17
Universal Vade-Mecum, Electron Valves and Semiconductor Devices
Taschenbuch zum Röhren-Codex 1948/49