A metal tube 1A7 was never existing. Octal- battery tubes were only made as glas types (1A7G, 1A7GT). We list the 1A7 because some schematics list as 1A7.
Testo in altre lingue
(può variare)
Bibliografia
Essential Characteristics, GE 1973
Taschenbuch zum Röhren-Codex 1948/49