TRACK CROSSING DISCRIMINATING CIRCUIT

摘要

Out of the read signal an auxiliary signal (Sa) having a relatively low frequency content is generated. The apparatus comprises for the auxiliary signal (Sa) first hold means (8) for generating a first hold signal (H1) and second hold means (9) for generating a second hold signal (H2). The first hold means (8) are adapted for temporarily maintaining the value of the first hold signal (H1) at a value substantially corresponding to the bottom value of the auxiliary signal augmented by an addition value (Sa+ DELTA ) and the second hold means for temporarily maintaining the value of the second hold signal (H2) at a value corresponding to a top value of the auxiliary signal diminished by a subtraction value (Sa- DELTA ).