3C50.75 - Noise and Measurements

Code Number:
Demo Title:
Noise and Measurements
Signal vs. Noise Ratios
Area of Study:
Oscilloscope, Microphone, Tuning Forks, Ultrasonic Rods, and Fan.

Plug the microphone into the oscilloscope and do a Fourier Transform to show the signal vs. noise strength.  Use the fan as the white noise source.

  • Ronald E. Jodoin and Wesley Irish, "Spectra of Electronic Noise Signals: A Microcomputer Experiment", AJP, Vol. 51, #4, Apr. 1983, p. 340.
  • Anthony A. Silvidi, "Noise Measurements in a University: An Open-Ended Student Experiment", AJP, Vol. 41, #7, July 1973, p. 909.
  • Roland Wittje, "Noise: From Nuisance to Research Subject", Physics Today, Vol. 73, #2, Feb. 2020, p. 42.
  • Megan F. McKenna, "The Sounds Around Us", Physics Today, Vol. 73, #1, Jan. 2020, p. 28.
  • Sung Chang, "Combing for a Signal Buried in Noise", Physics Today, Vol. 69, #3, Mar. 2016, p. 21.
  • Sheila Dwyer, "Squeezing Quantum Noise", Physics Today, Vol. 67, #11, Nov. 2014, p. 72.
  • Jearl Walker, "3.31. Sound Enhanced by Noise", The Flying Circus of Physics, p. 159.

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