With B5 base and B4 + sidecontact. Detector and HF and LF amplification.
Bibliografia
Taschenbuch zum Röhren-Codex 1948/49
- - Manufacturers Literature September 1929
Röhrencodex , Röhren-Taschenbuch 1950 23000 Röhren
Universal Vade-Mecum, Electron Valves and Semiconductor Devices
