• Country
• United States of America (USA)

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

• Year
• 1920

• Category
• Radio part (not a module) 

• Radiomuseum.org ID
• 192232

• • Brand: Synchrophase

• Wave bands
• - without

• Power type and voltage
• No Power needed

• Loudspeaker
• - - No sound reproduction output.

• Material
• Various materials

• from Radiomuseum.org
• Model: RPDA Dual Crystal Detector - Grebe, A.H. & Co.; Richmond

• Dimensions (WHD)
• 3 x 0 x 3 inch / 76 x 0 x 76 mm

• Notes
• Grebe RPDA Switchable Dual Crystal Detector Stand. Similar to the single crystal RPDB the RPDA featured two complete separate crystal detectors with switch for connecting either detector into a circuit.

• Net weight (2.2 lb = 1 kg)
• 0.5 lb (0 lb 8 oz) / 0.227 kg

• Price in first year of sale
• 7.00 $

• Literature/Schematics (1)
• 1921 Mesco catalog page 84

• Literature/Schematics (4)
• February, 1920 A. H. Grebe & Co. Bulletin R-104, R-105

• 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)