This circuit, which uses a quadruple comparator, was found in old American documentation. The response curve is shown next to the diagram and can be adjusted in the trimpots.
This conventional window detector circuit was found in a 1995 documentation. The trigger points, that...
Found in a Radio Electronics store from the 90s, this circuit is for cars of that era. The circuit...
This old circuit excites lamps but can be modified to excite high-power LEDs or other loads...