• Country
• United States of America (USA)

• Manufacturer / Brand
• Northwestern Radio Mfg. Co.; Portland, OR

• Year
• 1921/1922

• Category
• Radio part (not a module) 

• Radiomuseum.org ID
• 194123

• Wave bands
• - without

• Power type and voltage
• No Power needed

• Loudspeaker
• - - No sound reproduction output.

• Material
• Wooden case

• from Radiomuseum.org
• Model: Variometer Type SR-23 - Northwestern Radio Mfg. Co.;

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

• Notes
• The Northwestern Radio Manufacturing Company's SR-23 was a boxed variometer.

• Literature/Schematics (1)
• Northwestern Radio catalog.

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

• Other Models

• Here you find 17 models, 11 with images and 1 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Northwestern Radio Mfg. Co.; Portland, OR