$25    ChaQuO Chaos Generator/ Quadrature Oscillator PCB

$20    Component Kit

In-depth .pdf Docs emailed with purchase of PCB

Coming soon: ChaQuO Panels, Assembled Modules


A combination module including a chaos generator (CG)

and a quadrature oscillator (QO)

Ian Fritz, April 2008

The main function of this module is a versatile chaotic signal generator (CG). Chaotic signals are signals that have varying degrees of interesting irregularity without actually becoming random. This CG is an analog electronic simulation of the classical driven double potential-well problem, with the addition of extra gain in the circuit loop, and an extra cross-coupling path to extend the range of chaotic patterns available.

The double-well system is a "second-order" system and therefore requires an external driving signal.  This is provided by the second part of the module, a sinusoidal quadrature oscillator (QO).  The two parts of the module may be used together or separately. The CG may be driven by any output of the built-in QO or by any external oscillator.  The QO may drive the CG or be used independently as a four phase oscillator for the usual spatial modulation and other applications. Both parts of the module are manually controlled, to provide a compact, cost-effective unit.  The QO has a frequency span of ~0.03 Hz to ~3 kHz in two overlapping ranges.

The following link shows ChaQuO in action.  It is being used in conjunction with the T/G/T/S/H module to demonstrate how discrete chaotic signals can be derived from continuous ones.  The asymmetry in the Lissajou pattern is a result of using the extra cross-coupling signal. The sound clip shows the effect of triggering signals from different levels of the chaotic attractor.


Unusual parts you will need:



4 4.3V Zeners

4 1nF Polystyrene Caps

2 2.2uF Tantalum Caps

The four 100k linear board-mounted pots can be Spectrol .1” spacing or Alpha .2” spacing, which are not available at Mouser, but we have them here.

Board Size 2.625” x 5.75”