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Audio dosimeter

  • US 4,554,639 A
  • Filed: 04/06/1983
  • Issued: 11/19/1985
  • Est. Priority Date: 04/06/1983
  • Status: Expired due to Term
First Claim
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1. An audio dosimeter for measuring exposure to sound comprising:

  • (a) an electronic microphonic sound sensor means which generates electric input signal upon activation by sound;

    (b) an amplifier and weighting circuit electrically connected to the sound sensor means which amplifies the input signal from the sound sensor means and provides an "A" weighted signal directly related to the frequency of the sound which activated the sound sensor;

    (c) an x-squared detector circuit electrically connected to the amplifier and weighting circuit which receives the input signal and generates a voltage signal which is proportional to the log of the square of the input signal;

    (d) temperature compensation circuit electrically connected to the x-squared detector circuit which develops reference signals through ramping and intergrating means matched to the x-squared detector circuit and thereby temperature compensating the voltage signal of the x-squared detector circuit;

    (e) analog to digital time converter circuit electrically attached to the temperature compensation circuit which converts the temperature compensated voltage signal to digital time signal;

    (f) a microcomputer electrically connected to the temperature compensation circuit and controls the integrating and ramping functions of the circuit and electrically connected to the analog to digital time converter and controls the functions of the converter and receives the digital time signals from the converter and having a calculating means for converting the time signals into sound measurement values.

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