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.


Contact Resistance Terminal Voltage Sound Energy Space Orientation Contact Effect 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Springer-Verlag Berlin Heidelberg 1967

Authors and Affiliations

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

Personalised recommendations