• Country
• United States of America (USA)

• Manufacturer / Brand
• Operadio Corp.; St. Charles (IL)

• Year
• 1935 ??

• Category
• Audio Amplifier or -mixer

• Radiomuseum.org ID
• 238719

• • alternative name: Operadio Mfg,

• Number of Tubes
• 5

• Valves / Tubes
• 57 53 2A3 2A3 5Z3

• Main principle
• Audio-Amplification

• Wave bands
• - without

• Power type and voltage
• Alternating Current supply (AC) / 115 Volt

• Loudspeaker
• - This model requires external speaker(s).

• Power out
• 30 W (undistorted)

• Material
• Metal case

• from Radiomuseum.org
• Model: Theater Power Amplifier 455D - Operadio Corp.; St. Charles IL

• Shape
• Chassis only or for «building in»

• Dimensions (WHD)
• 430 x 200 x 180 mm / 16.9 x 7.9 x 7.1 inch

• Price in first year of sale
• 200.00 USD

• Author
• Model page created by KiTae Kim. See "Data change" for further contributors.

• Other Models

• Here you find 66 models, 43 with images and 32 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Operadio Corp.; St. Charles (IL)