• Country
• Germany

• Manufacturer / Brand
• Siemens (& Halske, -Schuckert Werke SSW, Electrogeräte); Berlin, München

• Year
• 1930 ?

• Category
• Audio Amplifier or -mixer

• Radiomuseum.org ID
• 5523

• Number of Tubes
• 4

• Valves / Tubes
• REN1104 REN1104 RV218 or RV258 RGN1054

• Main principle
• Audio-Amplification

• Power type and voltage
• Alternating Current supply (AC)

• Loudspeaker
• - For headphones or amp.

• from Radiomuseum.org
• Model: Protofon 3 - Siemens & Halske, -Schuckert

• Source of data
• Radiokatalog Band 1, Ernst Erb

• Circuit diagram reference
• Röhren in FS-Bestückungstabellen

• Other Models

• Here you find 2522 models, 2119 with images and 1334 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Siemens (& Halske, -Schuckert Werke SSW, Electrogeräte); Berlin, München