• Country
• United States of America (USA)

• Manufacturer / Brand
• Firestone Tire & Rubber Co. (Air Chief & Roamer, Airchief); Akron (OH)

• Year
• 1947

• Category
• Broadcast Receiver - or past WW2 Tuner

• Radiomuseum.org ID
• 40618

Click on the schematic thumbnail to request the schematic as a free document.

• Number of Tubes
• 6

• Valves / Tubes
• 6SK7 6SA7 6SF7 6SK7 6K6GT 5Y3GT

• Main principle
• Superhet with RF-stage; ZF/IF 455 kHz

• Tuned circuits
• 7 AM circuit(s)

• Wave bands
• Broadcast and Short Wave (SW).

• Power type and voltage
• Alternating Current supply (AC) / 117 Volt

• Loudspeaker
• Electro Magnetic Dynamic LS (moving-coil with field excitation coil) / Ø 6 inch = 15.2 cm

• from Radiomuseum.org
• Model: 4-A-21X - Firestone Tire & Rubber Co.

• Notes
• Push Button Abstimmung

• External source of data
• Ernst Erb

• Circuit diagram reference
• Rider's Perpetual, Volume 15 = 1947 and before

• Other Models

• Here you find 480 models, 313 with images and 438 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Firestone Tire & Rubber Co. (Air Chief & Roamer, Airchief); Akron (OH)