| 摘要 |
PURPOSE:To variably control the characteristics of wave shape equalizing filter in accordance with the positional information of the magnetic head, thereby enhance the reliablility of the double adjustment of the partial response system. CONSTITUTION:The isolated reproducing wave signal from the reproducing head is inputted through the delay line 31 and the track position signal C1 from the servo head is inputted. By these signals, interest of the respective amplifiers of the amplifier 34 is controlled, and the automatic equalizing control is carried out in such a manner that the amplitude characteristic is equalized every bit cell time. The respective outputs of the amplifier 34 is next inpressed into the adder 35 to obtain the correct partial response wave shape. Thus, since the characteristic property of the wave shape equalizing filter is most referably set in accordance with the track positional information, the precise partial response wave shape can be obtained inrrespective of the inner periphery or the outer periphery of the disc, the error in equalization influence is eliminated and the reliablility of the double adjustment can be enhanced. |
