Detector for sensing vehicles not stopping at traffic lights - has pulse generator connected to counter via latching circuit for use with low power speed sensing radar

摘要

The detector circuit operating in conjunction with low power radar spaced sensor is used to sense whether or not a motor vehicle stops at a red traffic light. The radar output signal is wave shaped (1) to control set to zero of a counter (2) which records pulses from a generator (3) via a latching circuit (4). A bistable (5) receives counter and radar signals and determines whether or not the vehicle has stopped. A detector loop output is signalled via relay with anti parasitic bistable (6). This signal is gated (8) with zero speed signal from the counter bistable. This allows the alarm relay (10) circuit to be operated.