A woodworking machine is disclosed having a base, a blade, a detection system adapted to detect a dangerous condition between a person and the blade, and a reaction system associated with the detection system to cause a predetermined action to take place upon detection of the dangerous condition. The present invention relates to a signal processing circuit 9 for reducing a PAPR of a modulated wave signal to be inputted to a power amplification circuit 5. The controller IC does not need a separate pin and ADC circuitry for sensing the input line voltage. The tuning elements may be implemented to provide uniformity in the access time through a range of conditions, such as drain voltages and temperatures.