This circuit is from a 90's documentation. The circuit is simple, as it uses only two transistors, and the control is done by pressure switches. The indication is done by LEDs.
Using transistorized regulators with NPN and PNP transistors we can create a symmetrical source of...
This circuit was found in a 1997 documentation. The signals are adjusted in a double 555 (556) and the...
We find this circuit in a 1980s documentation for amateur radio. The circuit shows how to switch...