• Country
• United States of America (USA)

• Manufacturer / Brand
• High Frequency Laboratories (HFL); Chicago, IL

• Year
• 1928

• Category
• Broadcast Receiver - or past WW2 Tuner

• Radiomuseum.org ID
• 44353

• Number of Tubes
• 10

• Valves / Tubes

• Main principle
• Superheterodyne (common); Screengrid 1926-1935

• Wave bands
• Broadcast only (MW).

• Power type and voltage
• Storage and/or dry batteries

• Loudspeaker
• - This model requires external speaker(s).

• Material
• Metal case

• from Radiomuseum.org
• Model: Isotone - High Frequency Laboratories

• Shape
• Chassis only or for «building in»

• Notes

• One dial (primary tuning control knob)

• Price in first year of sale
• 105.00 $

• External source of data
• Ernst Erb

• Source of data
• Radio Collector`s Guide 1921-1932

• Mentioned in
• The Radio Collector's Directory and Price Guide 1921 - 1965

• Literature/Schematics (1)
• Walter Ashe Radio Co. catalogue for season 1928-1929

• Other Models

• Here you find 32 models, 10 with images and 6 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from High Frequency Laboratories (HFL); Chicago, IL