• Year
  • 1954 ?
  • Category
  • Medical Technology
  • Radiomuseum.org ID
  • 272264

 Technical Specifications

  • Number of Transistors
  • Semiconductors present.
  • Semiconductors
  • Main principle
  • Audio-Amplification
  • Wave bands
  • - without
  • Details
  • Hearing aid
  • Power type and voltage
  • Dry Batteries / Mercury cell: 1 x 1.3 Volt
  • Loudspeaker
  • - only for Earphone!
  • from Radiomuseum.org
  • Model: Hearing Aid J2 - Amplivox Ltd.; Kidlington
  • Notes
  • Hearing aid with transistor.

    Low-consumption valves are used in the voltage-amplifying stages, but the greater part of the normal h.t. current is saved by using the transistor. A reduction from 0.35 mA in the all-valve model J to 0.04 mA in the J2, or a ratio of 120/1000 hours life. A single Mallory mercury cell (1.3 V) is user for l.t. Here the economy is 20 mA to 12.5 mA, or 50 to 80 hours.

    Air-to-air gain is 47 dB with E9L high-sensitivity earphone, compared with 53 dB in the all-valve J hearing aid.

  • Price in first year of sale
  • 44.10 GBP
  • Author
  • Model page created by Karl Dilcher. See "Data change" for further contributors.

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