Minifon Armband-Mikrofon - Wrist watch microphone ohne Schalter

Protona, R. Stach; Hamburg, Hannover (siehe auch Monske)

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  • Year
  • 1955 ??
  • Category
  • Microphone or Pick-up element
  • Radiomuseum.org ID
  • 325774

 Technical Specifications

  • Wave bands
  • - without
  • Power type and voltage
  • No Power needed
  • Loudspeaker
  • - For headphones or amp.
  • Material
  • Metal case
  • from Radiomuseum.org
  • Model: Minifon Armband-Mikrofon - Wrist watch microphone [ohne Schalter] - Protona, R. Stach; Hamburg,
  • Shape
  • Miscellaneous shapes - described under notes.
  • Dimensions (WHD)
  • 50 x 50 x 13 mm / 2 x 2 x 0.5 inch
  • Notes

  • Protona Armband-Mikrofon zur Verwendung z.B. mit dem Minifon P55. Das Kristallmikrofon ist in ein Armbanduhr-Gehäuse eines Chronographen eingebaut, die Uhr selbst ist Attrappe und hat keine Funktion.

    Ausführung ohne Schalter (Fernsteuerung des Minifons). Siehe auch Armbandmikrofon mit zusätzlicher Schaltfunktion.

    Wristwatch microphone.
    Microphone embedded in fake watch
    Microphone with crystal transducer
    There is no watch mechanism, the hands do not move.
    Buttons not operational in the normal model.
    There is a version in which the buttons act as a remote control for the M51 or M55 recorder.
    Microphone output on internally connected and non-removable cable.
    1 meter long cable to end in a 3.5 mm audio plug.
    Typical DC impedance:  measured from 4 MΩ to 5 MΩ.
    Maximum output signal of about 500 mV of amplitude when submitted to a loud voice.
    Leather bracelet.

    Application
    Used in espionage operations as an input to the spy recorders manufactured by Minifon and Protona in the period from 1950 to 1965.
    The cable was hidden under the sleeve of the shirt and carried the signal to the pocket recorder.

  • Net weight (2.2 lb = 1 kg)
  • 0.050 kg / 0 lb 1.8 oz (0.11 lb)
  • Mentioned in
  • - - Manufacturers Literature
  • Literature/Schematics (1)
  • DBP - Patent Nr. 1875750, eingetragen 18.7.1963
  • Literature/Schematics (2)
  • Der Spion in der Tasche; Roland Schellin; ISBN 3-936012-00-8
  • Author
  • Model page created by Moisés Piedade. See "Data change" for further contributors.

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The model Minifon Armband-Mikrofon - Wrist watch microphone is part of the collections of the following members.

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