I use this sine generator when I need to debug a project using an audio probe. Before building this, I had to strum my guitar and then quickly probe my project before the guitar signal was dead.
Verified! I built one and it peeps happily at around 783Hz.
Schematic and project info: http://www.geofex.com/FX_images/q&dosc.pdf
Click here to see the bill-of-materials as a list or download it as a comma separated values file (.csv).
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