We found this circuit in Radio Electronics from the 90s. The components are current. The sensor is a common general-purpose transistor. The connection to the sensor is made by twisted pair.
In the figure we have one of the many ways to program the counting of a 4017. The circuit uses...
We found this configuration of band rejector filter or band rejector with operational 741 in a...
This circuit causes a green LED to light up when we step on the brakes and the rear lamps to light...