• Year
  • 1928 ?
  • Category
  • Audio Amplifier or -mixer
  • Radiomuseum.org ID
  • 102853

Click on the schematic thumbnail to request the schematic as a free document.

 Technical Specifications

  • Number of Tubes
  • 4
  • Main principle
  • Audio-Amplification
  • Wave bands
  • - without
  • Power type and voltage
  • Alternating Current supply (AC) / 110-115 Volt
  • Loudspeaker
  • - This model requires external speaker(s).
  • Material
  • Various materials
  • from Radiomuseum.org
  • Model: 250 Power Amplifier - Thordarson Electric Mfg. Co. ;
  • Shape
  • Chassis only or for «building in»
  • Notes
  • Note: Riders schematic shows (2 times!) a UX227 which is not correct!. It must be a UY227.
  • Price in first year of sale
  • 78.00 $
  • Circuit diagram reference
  • Rider's Perpetual, Volume 1 = 1931/1934 (for 1919-1931)
  • Literature/Schematics (1)
  • Chicago Salvage Stock Store catalogue, 1928?
  • Author
  • Model page created by Vitor Oliveira. See "Data change" for further contributors.

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