| 摘要 |
PURPOSE:To improve the phase characteristics of a low band of a data signal by demultiplexing a track position signal through a filter and then subtracting the demultiplexing output from a reproduced signal. CONSTITUTION:A magnetic head 41 delivers both data and track position signals at a time and supplies them to an amplifier 42, and the components of track position signals are selected through filters 43 and 44 by the output of the amplifier 42. The outputs of these filters are connected to phase shifters 45 and 46 respectively, and the outputs of shifters 45 and 46 are supplied to a demodulator 60 for track position signal. Thus a track position demodulating signal is produced and delivered to an output terminal 61. At the same time, the outputs of shifters 45 and 46 are supplied to an adder 47 and compounded. The output of the adder 47 is supplied to a subtractor 48, and the output of the adder 47 is subtracted from the output of the amplifier 42. Thus the output of the adder 47 contains the track position signal component only; while the output of the subtractor 48 contains only the data signal component. These outputs are suppled to a data signal detector 49. Then a data signal pulse is produced and delivered to an output terminal 50. |
