DIY Function (Signal) Generator

Here is my homemade function generator that can produce a square, triangle, and sign wave. This is all done with a few bucks worth of parts. The heart of the function generator is a LM324N quad OpAmp. Here is a link to the original site, the kit is now discontinued. http://circuitspecialists.com/prod.itml/icOid/4065 I have a direct download for the PDF file instructions and schematic on my blog post here: http://www.electronhacks.com/2011/10/diy-function-signal-generator/