Contact effects in carbon granular microphones

  • Ragnar Holm


The carbon granular microphone, or transmitter, is universally used in telephone communication1. Other microphone types used for radio, loudspeakers etc. provide much higher fidelity to the audio waves, but they require costly additional amplifiers. As we shall see, the carbon transmitter itself amplifies the sound energy by a factor of several hundred. It has the great merit of low cost.


Burning Hone Anthracite 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1967

Authors and Affiliations

  • Ragnar Holm
    • 1
  1. 1.St. MarysUSA

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