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Interested in disability history? Check out what happened Today in AT History!

July 23

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Deaths

  • 1981 - Harvey Fletcher - credited with the invention of the hearing aid and audiometer.
  • 1943 - Valdemar Poulsen - Danish Engineer. Poulsen invented the telephone answering machine which used magnetic recording which was invented a few years earlier by Oberlin Smith.[1]


References

  1. Allen, Bob. "100 YEARS OF MAGNETIC RECORDING: POULSEN'S PATENT." Association of Motion Picture Sound. 1998. Accessed on March 13, 2008.