AUTOMATIC EQUALIZING AND PHASE MODIFYING SYSTEM

PURPOSE:To attain the automation of recovery equalization and phase modification by preparing plural binarizing circuits including binarizing circuits or equalizing circuits and using plural error detection circuits so as to retrieve the combination of optimum parameter in real time, and using the parameter stored at normal reproduction. CONSTITUTION:An output A-1 of a head A1 of a channel A is amplified sufficiently by a preamplifier A2, the output of a head B1 is amplified by a preamplifier B2 and an output of a head C1 is amplified by a preamplifier C2 similarly and three outputs are distributed in parallel with switchers A8, B8 and C8. Then the equivalent parameter of the equalizers A3, B3 and C3 is changed little by little and the parameter alpha is selected by q-kind from '0' to (q-1). In such a case, assuming that the parameter of the equalizer B3 is set to alphax, alphax-1 is set to the equalizer A3 and alphax+1 is set to the equalizer C3. As to the error, in case of A>B>C, the parameter (x) is increased by one and in case of A=C, the parameter alphax is used as a decided value. Thus, the optimum equalization is detected for automatic equalization.