Logik-Analysator (Oszilloskop)

In most windscreen wiper delay circuits the wiper speed is indepen-dent of the speed of the car. However the faster the car travels, the more rain falls on the windscreen, therefore, ideally, the shorter the delay should be. A variable delay circuit could be controlled by a sensor mounted in the speedometer cable. However this approach would be fairly compli-cated. The simpler solution adopted here, is to derive the control signals from the contact breaker, so that the wiper speed is varied in accordance with the engine speed.