|
Regardless
of whether you call it a Lissajous pattern or 'quadrature art,' there
is a coolness about feeding signals into the X and Y axes of an oscilloscope
and watching the patterns that emerge on the CRT (or possibly LCD these
days) display. Using static waveshapes can create amazing-enough Etch-A-Sketch
type drawings, but animating the on-screen patterns with time-varying
signals into one or both axes really spiffs up the results. This short
article by
Russ Williams on the EDN website presents a few simple circuits
for generating some of the quadrature art examples shown in the thumbnail
below. A solderless breadboard, quad opamp IC, and a handful of resistors,
capacitors, and inductors will get you started. For test equipment,
a simple DC power supply, a waveform generator capable of outputting
sine, square, and triangle signals, and, of course, an oscilloscope,
are all that are needed.
 Of
course actual hardware in the form of an arbitrary waveform generator
and an oscilloscope is not required to enjoy the show - indeed software
emulation will get the job done - any other method loses much of the
awe and mesmerizing factor.
Posted September 25, 2013
|
