WAVEFORM SHAPING CIRCUIT FOR MEASURING FREQUENCY OF FUNDAMENTAL WAVE OF DISTORTED WAVE

PURPOSE:To measure a fundamental frequency extending from a low frequency to several kHz, by constituting the titled circuit so that an output signal of an RS-FF is divided by a frequency dividing FF, and thereafter, brought to frequency multiplication. CONSTITUTION:An input signal being a distorted wave is led to comparators A1, A2, and an output of the comparator A1 is led to one input terminal of an RS-FF L1, and an output of the comparator A2 is led to the other input terminal of the FF L1 through an inverter NOT. As a reference signal for a comparison, signals -VP1, +VP2 are inputted to the comparators A1, A2, respectively. Also, the FF L1 is brought to an inversion control each time by the input signal. An output signal of the FF L1 is divided by a frequency dividing FF L2, and also an output signal of the FF L2 is two-multiplied as to its frequency by a frequency multiplying circuit 1, by which a pulse signal of a pulse width being equal to a half period of a fundamental wave of a distorted wave is obtained.