This circuit uses common components at the time of its publication in the 1980s. The circuit can be made with modern equivalent transistors. The input signal is sinusoidal.
This circuit, found in an American publication from the 1970s, produces an audible tone in a...
This circuit was found in a 2006 publication. It can serve as the basis for a microcontrolled...
By adding a transistor to the output and some polarization features we can obtain a higher output...