• Country
• United States of America (USA)

• Manufacturer / Brand
• National Company; Cambridge & Malden (MA)

• Year
• 1932 ?

• Category
• Broadcast Receiver - or past WW2 Tuner

• Radiomuseum.org ID
• 49547

• • alternative name: National Toy Co.
  • Brand: Thrillbox

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

• Number of Tubes
• 3

• Valves / Tubes
• 36 36 37

• Main principle
• TRF with regeneration

• Wave bands
• Broadcast, Long Wave and Short Wave.

• Power type and voltage
• Dry Batteries / 6 / 67/135 Volt

• Loudspeaker
• - For headphones or amp.

• Material
• Metal case

• from Radiomuseum.org
• Model: SW-3 Model I [var 3] - National Company; Cambridge &

• Shape
• Tablemodel, with any shape - general.

• Notes
• plug-in coils series "10-22" for coverage 90 - 35000 kHz;
  headphones operation only, no audio output stage, optional DWG audio amplifier
  can be changed to AC operation by substituting tubes 35 35 27

• External source of data
• Ernst Erb

• Circuit diagram reference
• Rider's Perpetual, Volume 14 = 1944 = before 1943

• Other Models

• Here you find 446 models, 285 with images and 189 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from National Company; Cambridge & Malden (MA)