REPRODUCING EQUALIZATION DEVICE

PURPOSE:To perform reproducing equalization wit high accuracy with simple circuit constitution by providing a balanced modulator, a band-pass filter, an oscillator, a phase shifter, and a synchronous detector to obtain equalization output by performing the synchronous detection of the output of the band-pass filter by the output of the phase shifter. CONSTITUTION:The balanced modulator 2 performs the balanced modulation of a continuous wave with a constant frequency generated at the oscillator 5 by a signal applied via an input terminal 1. Also, the output of the oscillator 5 is supplied to the phase shifter 6, and phase shifting by a prescribed angle is performed at the phase shifter 6. The output of the phase shifter 6 is applied on the synchronous detector 4, and the synchronous detection of the output of the band-pass filter 3 is performed by the output signal of the phase shifter 6 at the synchronous detector 4. And the output of the synchronous detector 4 is taken out via an output terminal 7. In such a way, the balanced modulation of a reproduced signal with the continuous wave is performed, and the synchronous detection of only one side band component is performed by the continuous wave with a phase different from that of the continuous wave, then, prescribed equalization is performed.