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 circuit uses integrated 555 and an amplification step with transistors, as we can see in the...
This circuit uses components that are still common despite being from 1995 documentation. The circuit can...
This circuit was obtained from American documentation from the 1990s. The transformer can be a car...