Have you ever wondered how speed guns measure the speed of moving vehicles or how an athlete's sprint speed is recorded? Normally these speed sensors work with radar or laser technology to bounce back ...

DAOKAI 5PCS LM393 Comparator Speed Sensor Module Slot Type IR Optocoupler for Motor Speed Detection Also for MCU Arduino, with Dupont Wire Comimark 4PCS Tilt Sensor Module Vibration Sensor for Arduino ...