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DIY Audio function generator

Posted on Friday, May 4th, 2012 in project logs by DP

DIY Audio function generator  is a low-distortion function generator which operates in the Audio frequency range. Conventional function generators use a square wave signal to generate the other waveforms like triangle, or sine wave. This approach adds noise to the sine wave output, which is the one waveform Eric wants for his audio development.

His workaround is to reverse the process, or use a sine-wave signal to generate the other waveforms.  This approach will generate a much cleaner sine-wave output while still having other waveforms as options.

Sine Wave Generator based on the #327 Lamp Wien-bridge Circuit to get the low THD. I’ll then feed that into a Comparator to produce the Square wave; I am then using the Square Wave to turn on/off a ramp generator circuit. I would rather have a ramp output vs a triangle wave. The ramp circuit will let me play around with different single & dual slope ADC concepts later on.

Via the forum.

This entry was posted on Friday, May 4th, 2012 at 7:00 pm and is filed under project logs. You can follow any responses to this entry through the RSS 2.0 feed. You can skip to the end and leave a response. Pinging is currently not allowed.

One Response to “DIY Audio function generator”

  1. john says:

    So eerie, as I was sketching a very similar circuit last week with the same goal in mind.

    Nicely done!

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