A Vacuum-Tube-Type Transducer for Use in the Reproduction of Lateral Phonograph Recordings

A method is described wherein the lateral mechanical vibrations from a phonograph record are used to move a vacuum-tube element which creates variations in the anode current comparable to the anode-current variations caused by a change in grid voltage in the regular triode-type vacuum tube. An experimental-type movable-grid tube is shown, with the performance data. An applicable circuit is shown and other uses of the tube are mentioned.