Periodical signal detection circuit in a reproducing apparatus

摘要

A periodical signal detection circuit is designed for use in an apparatus which reproduces an information signal and a periodical signal from a recording medium. A separation circuit separates the periodical signal from the reproduced signal. A reference pulse is generated at a repetition frequency which is the same as the frequency of the periodical signal. A first gate circuit responds to the periodical signal obtained from the separation circuit and to the reference pulse signal. A first counter produces an output by counting N of the reference pulses (N is an integer greater than or equal to 2). A second gate circuit passes the signal from the separation circuit according to the output of the first counter. An output circuit detects the signals in responsive to the reference pulse, and the output of either the first or the second gate circuit.