• Country
• United States of America (USA)

• Manufacturer / Brand
• Watkins Johnson Company, Gaithersburg (MD)

• Year
• 1970 ??

• Category
• Radio module post 1925 (not a part, not a key)

• Radiomuseum.org ID
• 89300

• Number of Transistors
• Semiconductors present.

• Semiconductors

• Loudspeaker
• - - No sound reproduction output.

• Material
• Metal case

• from Radiomuseum.org
• Model: DRO-290A-1 - Watkins Johnson Company,

• Shape
• Rack

• Dimensions (WHD)
• 19 x 1.5 x 18 inch / 483 x 38 x 457 mm

• Notes
• digital frequency readout matching the 521A-3 SW/VHF receiver; displays up to 0,1 kHz with nixie tubes.

• Author
• Model page created by Martin Bösch. See "Data change" for further contributors.

• Other Models

• Here you find 18 models, 9 with images and 1 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Watkins Johnson Company, Gaithersburg (MD)