• Country
• United States of America (USA)

• Manufacturer / Brand
• Grebe, A.H. & Co.; Richmond Hill (NY)

• Year
• 1919

• Category
• Audio Amplifier or -mixer

• Radiomuseum.org ID
• 216273

• • Brand: Synchrophase

• Number of Tubes
• 2

• Valves / Tubes
• VT-Class-II or A_Moorhead VT-Class-II or A_Moorhead

• Main principle
• Audio-Amplification; 2 AF stage(s)

• Wave bands
• - without

• Power type and voltage
• Storage and/or dry batteries

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

• Material
• Wooden case

• from Radiomuseum.org
• Model: Two-Stage Audio Amplifier RORB [with step control] - Grebe, A.H. & Co.; Richmond

• Shape
• Tablemodel, Box - most often with Lid (NOT slant panel).

• Dimensions (WHD)
• 6.5 x 6.5 x 0 inch / 165 x 165 x 0 mm

• Notes
• 1919 Grebe Two-Stage Audio Amplifier Type RORB - In the RORB, the use of either one or two stages of amplification is obtained with a cam switch which controls the filament circuits as well as the input and output connections.

• Price in first year of sale
• 45.00 $

• Mentioned in
• July 1919 National Radio Supply Co. catalog page 28-29

• Author
• Model page created by Alan Larsen. See "Data change" for further contributors.

• Other Models

• Here you find 188 models, 124 with images and 60 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Grebe, A.H. & Co.; Richmond Hill (NY)