Found in a 1967 Electronics World, this oscillator changes its tone when objects move in their environment. The output is made on a low impedance phone.
This circuit can be powered by 2 or 3 small batteries. The resistor can have values between 220...
These circuits from a May 1994 Electronics Now take advantage of the noise from the junctions of...
This network can be used in a sound project to control the tone. The circuit is from an...