• Country
• United States of America (USA)

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

• Year
• 1935 ?

• Category
• Commercial Receiver (may include amateur bands)

• Radiomuseum.org ID
• 281376

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

• Number of Tubes
• 9

• Valves / Tubes
• 58 58 57 57 58 58 2B7 2A5 57

• Main principle
• Superhet with RF-stage; ZF/IF 456 kHz; 2 AF stage(s)

• Tuned circuits
• 11 AM circuit(s)

• Wave bands
• Broadcast plus more than 2 Short Wave bands.

• Power type and voltage
• Powered by external power supply or a main unit.

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

• Power out
• 1.5 W (unknown quality)

• Material
• Metal case

• from Radiomuseum.org
• Model: HRO Prototype [1.0 modified] - National Company; Cambridge &

• Shape
• Boatanchor (heavy military or commercial set >20 kg).

• Dimensions (WHD)
• 438 x 223 x 300 mm / 17.2 x 8.8 x 11.8 inch

• Net weight (2.2 lb = 1 kg)
• 14.5 kg / 31 lb 15 oz (31.938 lb)

• Literature/Schematics (1)
• Rider's Perpetual, Volume 8 = 1937 and before (NATIONAL PAGE 8-1)

• Author
• Model page created by Michael Gnaedig-Fischer. See "Data change" for further contributors.

• Other Models

• Here you find 445 models, 284 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)