Abstract: A method and system and associated circuitry for controlling and stopping the motion of dangerous moving parts such as power saw blades substantially instantaneously in response to body or human capacitance produced by an operator coming with a predetermined critical distance from the moving part. This method includes, and this system provides for, among other things, connecting an antenna to the moving part and then coupling a tunable circuit to the antenna so that the antenna provides a variable lumped capacitance parameter (dependent upon human body capacitance) within the tunable circuit. This lumped capacitance parameter is variable in response to body or human capacitance produced when an operator comes within a predetermined critical proximity to the moving part.