This circuit, found in a 1964 US documentation, consists of a selective amplifier that lets only 10 Hz pass around a 400 Hz center frequency with the indicated components.
The transistors for this circuit from an 80's documentation can be the BC548 or 2B222 and the...
In the figure we show a timer, which is simpler because it uses only one of the four gates of the...
This circuit checks the infrared emission of a common remote control. We found it in the March 1993...