FB-7 Series Coils

National Company; Cambridge & Malden (MA)

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  • Year
  • 1933–1936
  • Category
  • Radio part (not a module) 
  • Radiomuseum.org ID
  • 286307
    • alternative name: National Toy Co.
    • Brand: Thrillbox

 Technical Specifications

  • Wave bands
  • Wave Bands given in the notes.
  • Power type and voltage
  • No Power needed
  • Loudspeaker
  • - - No sound reproduction output.
  • Material
  • Special material, described in the notes.
  • from Radiomuseum.org
  • Model: FB-7 Series Coils - National Company; Cambridge &
  • Shape
  • Miscellaneous shapes - described under notes.
  • Notes

  • The National FB-7 Series Coils are wound on R-39 coil forms and are protected by a bakelite sleeve with a metal "handle" to facilitate removal from the receiver. (R-39 is a low-loss dielectric.) The coils also have National's special 6-prong base, which is not compatible with standard 6-pin tube bases or sockets. These coils are air-tuned.

    Each band requires an Oscillator and Detector coil, and are marked "OSC" and "DET" along with the frequency range. These coils plug into the front of the receiver.

    Coils were not supplied with the receiver. Each band cost $10 (US) per pair of coils.

    Note: The original coils were air tuned, but the National Bulletin No. 240 from 1934 shows both air and mica tuned coil form options. It is unclear if these correlate to the FB-7 and FB-7A receivers, as National literature used the designations "FB-7" and "FB-7A" interchangeably. Also, it is unclear if the mica tuned coil forms were ever used for production models.

    Coil Freq. Range
    FB AA 18 - 34 MHz
    FB A 11.4 - 19.5 MHz
    FB B 7.0 - 11.7 MHz
    FB C 4.0 - 7.3 MHz
    FB D 2.4 - 4.2 MHz
    FB E 1.5 - 2.5 MHz
    FB F 0.9 - 1.5 MHz
    AB 20 20 Meters
    AB 40 40 Meters
    AB 80 80 Meters
    AB 160 160 Meters

     

  • Price in first year of sale
  • 10.00 USD
  • Mentioned in
  • National Catalog No. 220 - 1933
  • Author
  • Model page created by Wayne Childress. See "Data change" for further contributors.

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The model FB-7 Series Coils is part of the collections of the following members.

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