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 was found in the April 1978 Radio Electronics magazine. The power supply must be...
This audio amplifier stage was found in a 1963 publication. The circuit was designed to use...
Connected to the output of an audio amplifier or radio this circuit indicates the level of the...