| 摘要 |
PURPOSE:To easily discriminate the quality of a magnetic head regarding the influence of field through even at the stage of a regular maintenance operation after a magnetic recorder using the magnetic head is delivered to a user, by setting a prescribed threshold value to a read signal. CONSTITUTION:A slice level generator 18 which outputs slice level information indicating that out of original read signals how many % and more must be recognized as read signals (for example, 10%, etc.), is controlled by a control circuit 20 which operates in accordance with a slice level designating signal Ss. An amplitude detecting circuit 19 which inspects the amplitude of the output signal of a gain adjusting circuit 14 which responds to a detect signal from a read head 3, sets a threshold value Th which determines that out of signals outputted from the gain adjusting circuit 14 signals above what level must be inputted in the next-stage differentiation circuit 15 as read signals, in accordance with the slice level information from the slice level generator 18 during the period when a read starting signal Sr is outputted from a host device. |
