Automatic discrimination of scanning modes by which video signals were recorded.

摘要

In order to discriminate automatically scanning modes of recorded signals in a video recording/reproducing apparatus such as a video tape recorder, horizontal synchronizing signals output from a video demodulating circuit 5 are supplied to a period measuring portion 6 to measure their period. An output from the period measuring portion 6 is supplied to a comparing portion 7 including comparators 7a and 7b. The comparator 7a is supplied with a first reference signal from a terminal 8, and the comparator 7b with a second reference signal from a terminal 9, such that the output from the period measuring portion 6 is compared with the reference signals in the comparators 7a and 7b, respectively. Based on a result of the comparison, the comparing portion 7 sends a switching signal to a servo control circuit 10.