Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Time-stamping and Discretising Audio Signals into Raw Data

  1. Mar 13, 2010 #1
    I'm logging the RPM of a scaled wind turbine using a laser and modified microphone (with a photocell instead of a coil).

    The signal is recorded using Audacity and is a series of troughs separated by the time it takes for one blade to pass through the beam (please see attached image below).

    Is there a way to convert this signal into an array of time-stamps and signal strengths (0.0 to 1.0)?

    I aim to eventually have a time vs. instantaneous RPM plot.

    Attached Files:

    • PF.jpg
      File size:
      10.7 KB
  2. jcsd
  3. Mar 20, 2010 #2


    User Avatar
    Gold Member

    Does Audacity support exporting your data into a csv style or similar format? What is the worst case value you might expect for RPM?

    Are you able to interface to some signal conditioning circuit and then a uC? Maybe you want to leave the uC out of the picture and do some low level programming and interface your signal conditioning circuit to a port (serial/parallel) via an ADC?
  4. Mar 21, 2010 #3
    Thanks for your response. We're now pursuing your method.

    Would you have any advice on the ADC/computer interface?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook