| 摘要 |
PURPOSE:To eliminate a pattern peak shift due to a waveform interference between magnetization inversions caused in a read waveform from a magnetic recording medium by using a tapped transversal equalizer so as to control the tap gain. CONSTITUTION:An equalizer 3 consists of two stages of delay elements 4, 4' retarding sequentially an output signal A of a preamplifier 2 and outputting it as signals B, C, variable tape gain circuits 5, 5' connected to an output tap of the signals A, C and an adder circuit 6 adding inverting outputs A', C' of the said gain circuit to the signal B. The delay elements 4, 4' retard signals at an inter-tap delay time Td corresponding to a minimum bit cell interval of a recording signal, for example and the signals A, C are echo lead/lag echo signals respectively with respect to an isolated waveform B outputted to the intermediate tap as a reference. the echo signals A, C are attenuated properly by giving them to tap gain circuits 5, 5', and equalized output waveform D compressed into a minimum bit cell is obtained from the adder circuit 6 by synthesizing the attenuated signals A', C' in a form of subtraction from the signal B. |
