This CPO is made complete from discrete components and produces a very pleasant sinusoidal output. The output level is fairly low and is suitable for headphones or line-in use, but cannot drive a speaker directly. If you would like to have loudspeaker output, please plug this circuit into an amplified speaker. A Manhattan-style construction layout diagram is attached. By using this layout, you can fit this circuit and a 9 volt battery into an Altoids tin.

Schematic: