Apparatus for peak detection in magnetic recording

摘要

An apparatus is disclosed for detecting the peaks of a signal recorded on a magnetic storage medium. An absolute value circuit is used to generate an output that is approximately equivalent to the mathematical absolute value of the raw signal input from the storage medium. The absolute value signal is then coupled to both a differentiator circuit and a noise rejection comparator circuit. A second comparator which detects the zero voltage crossings of the differentiator circuit is enabled and disabled by the output from the noise rejection comparator so that transitions of opposite polarity are produced, corresponding to the peaks and positive going reference level crossings of the raw signal input, while noise on the raw signal input below a qualification level established by the noise rejection comparator circuit is rejected. The output of the second comparator is then coupled to a monostable multivibrator which produces digital pulses of a desired period which correspond to the peaks of the signal record on the magnetic storage medium.