Signal reproducing apparatus having waveform equalizing function

摘要

A circuit is provided for emphasizing or suppressing both a frequency corresponding to an upper sideband and a frequency corresponding to a lower sideband with respect to a frequency corresponding to the carrier of a frequency-modulated signal in equalizing the frequency-modulated signal reproduced from the recording medium. With this arrangement, it is possible to effectively compensate for the nonlinearity of a magnetic recording and reproducing system even in the case of a wide deviation. Also, the envelope levels of the portions of a frequency-modulated signal which are formed by frequency-modulating portions of a signal whose levels differ from each other, are extracted to adjust the equalizing characteristics of the equalizing circuit in accordance with the difference between the levels, whereby variations in the characteristics of a reproduction equalizing circuit due to variations with time can be appropriately compensated for.