• Country
• United States of America (USA)

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

• Year
• 1964 ??

• Category
• Radio module post 1925 (not a part, not a key)

• Radiomuseum.org ID
• 87634

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

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

• Number of Transistors
• 8

• Semiconductors

• Main principle
• RF-Circuit or wave trap (separate, can also be an antenna with amp.)

• Wave bands
• Long Wave and/or Very Low Frequency (VLF).

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

• Loudspeaker
• Permanent Magnet Dynamic (PDyn) Loudspeaker (moving coil) / Ø 3 inch = 7.6 cm

• Power out
• 1.5 W (max.)

• Material
• Metal case

• from Radiomuseum.org
• Model: VLF Preselector LF-10 - National Company; Cambridge &

• Shape
• Tablemodel, with any shape - general.

• Dimensions (WHD)
• 16.5 x 3.5 x 12.75 inch / 419 x 89 x 324 mm

• Notes

• The National LF-10 VLF Preselector was designed to be used with the National HRO-500 receiver. It covers 5-500 kHz in four bands. An optional audio filter was available.

• Net weight (2.2 lb = 1 kg)
• 12 lb (12 lb 0 oz) / 5.448 kg

• Source of data
• Shortwave Receivers - Past & Present (3rd ed.)

• Author
• Model page created by Martin Bösch. 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)