| 摘要 |
PURPOSE:To optimize the characteristic of an equalizer by providing the equalizer whose characteristic is changed by a variable gain amplifier inputting an output signal of a read only memory whose initial setting is made possible and changing the amplification factor by this signal. CONSTITUTION:The characteristic is measured at a proper track interval possible for interpolation to each magnetic head at check of a magnetic head and disc assembly and a gain constant data 22 of the variable gain amplifier 14 optimizing the equalizer 34 is recorded to a ROM 18 via a terminal 23 externally corresponding to each magnetic head address and track address. magnetic head address signals 18', 19 and a track address signal 20 at designated from a high-order device in operation, the address of the ROM 18 is designated and the equalizer 34 is optimized by the constant, which is outputted as a ROM data 21, the gain of the variable gain amplifier 14 is set by using the signal of the ROM data 21 to optimize the equalizer 34. Even when any magnetic head address or track address is designated, the peak shift is reduced without causing large over-compensation. |
