• Country
• United States of America (USA)

• Manufacturer / Brand
• Kellogg Switchboard & Supply Co.; Chicago (IL)

• Year
• 1925

• Category
• Radio part (not a module) 

• Radiomuseum.org ID
• 222932

• • Brand: Wavemaster

• Wave bands
• - without

• Power type and voltage
• No Power needed

• Loudspeaker
• - - No sound reproduction output.

• Material
• Various materials

• from Radiomuseum.org
• Model: Audio Frequency Transformer 501 - 502 - Kellogg Switchboard & Supply

• Notes
• Type 501 : ratio 4.5 to 1
  Type 502 : ratio 3 to 1

• Price in first year of sale
• 5.00 USD

• Mentioned in
• Radio Broadcast, Feb. 1925, p. 848c

• Author
• Model page created by Hans-Joachim Korn † 16.11.15. See "Data change" for further contributors.

• Other Models

• Here you find 66 models, 25 with images and 17 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Kellogg Switchboard & Supply Co.; Chicago (IL)