Code Practice Oscillator

This website is the continuation of my old website at That site is no longer maintained but I intend to keep it active for the foreseeable future. The original version of the CPO1 Code Practice Oscillator is described there.

Here is a photo of the assembled kit in its current configuration:

CPO1 Code Practice Oscillator

Based on feedback received from the initial run of kits, there are a couple of changes to the CPO1.

  1. The key jack (J2) has been rewired to accept either a stereo or mono 3.5mm plug.
  2. C6 has changed from a 100nF capacitor to a 10uF electrolytic.

The new schematic is shown below. A PDF version can be downloaded here: CPO1 Schematic

The manual for the kit can be downloaded here:
CPO1 Assembly and Operations Manual

CPO1 Code Practice Oscillator Schematic