• 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
• 49539

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

• Number of Tubes
• 3

• Valves / Tubes
• 32 32 30

• Main principle
• TRF with regeneration

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

• Power type and voltage
• Dry Batteries / 1,4 / 3/67/135 Volt

• Loudspeaker
• - For headphones or amp.

• Material
• Metal case

• from Radiomuseum.org
• Model: SW-3 Model I [var 2] - National Company; Cambridge &

• Shape
• Tablemodel, with any shape - general.

• Dimensions (WHD)
• 250 x 200 x 280 mm / 9.8 x 7.9 x 11 inch

• Notes
• The National SW-3 Model I (2VDC SW-3) uses plug-in coils series "10-22" for coverage 90 - 35000 kHz. Headphones operation only, no audio output stage. The National 2V DC SW-3 is the Direct Current version of the National SW-3. It uses different tubes, but basically the same circuit as the 6V DCSW-3 (6 volt DC version) or the ACSW-3 (the 110VAC version).

• Net weight (2.2 lb = 1 kg)
• 5.4 kg / 11 lb 14.3 oz (11.894 lb)

• 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)