• Country
• Great Britain (UK)

• Manufacturer / Brand
• Harding, Holland & Fry, London

• Year
• 1923

• Category
• Detector-Radio (Crystal or diode, without tubes/transistors)

• Radiomuseum.org ID
• 76601

• • Brand: OTB (O.T.B.)

• Main principle
• Crystal or Solid State Detector

• Tuned circuits
• 1 AM circuit(s)

• Wave bands
• Broadcast only (MW).

• Power type and voltage
• No Power needed

• Loudspeaker
• - For headphones or amp.

• Material
• Wooden case

• from Radiomuseum.org
• Model: OTB Type B - Harding, Holland & Fry, London

• Shape
• Miscellaneous shapes - described under notes.

• Notes
• Circular turned oak "powder-box" 5"dia., 2.5"high, like Type A, but with sockets instead of terminals; BBC/PMG stamp, GPO No.745; internal ligthning protector. A deluxe version in ivory with brass feet was also available (rare).

• Source of data
• Tickling the Crystal; Sanders

• Author
• Model page created by Konrad Birkner † 12.08.2014. See "Data change" for further contributors.

• Other Models

• Here you find 2 models, 2 with images and 0 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Harding, Holland & Fry, London