I built the Annoizer with the purpose of practicing my PCB organization and soldering skills. It uses a 555 timer to drive a speaker.
There are controls for sound frequency and volume. There is also a pitch shift button, for basic effects.
If you use the materials on this page, or any other page on this web site, you do so at your own risk. They are provided "as is". No warranty is provided or implied. I neither guarantee that the materials will work, nor that they will not be harmful in any way.