This circuit decodes a 1800 Hz tone used in communications. The circuit is from an American documentation for radio amateurs of the 80's. Equivalent component can be used.
This special effect circuit with LEDs using the 4017 was obtained in a 1982 publication. LEDs are...
Found in a 1967 Electronics World, this circuit uses unusual components today. The transformer has a high...
In the figure we have the basic configuration of a rectangular oscillator using an operational amplifier...