Patent ID: 7706533

Claim:
Apparatus for narrowing line synchronization pulses in a video signal which includes positive going pulses to cause a reduced amplitude video signal on a recorded copy by a video recorder, comprising: a first timing circuit to provide indications of synchronizing pulses of the video signal: a line selector circuit to provide a line selector signal indicative of at least one set of selected lines of the video signal, wherein one or more of the selected lines is at a location in a non-overscan area; a second timing circuit to provide the narrow line synchronization pulses each being in a horizontal blanking interval of the video signal; and logic circuitry to combine the line selector signal with the output of the second timing circuit and which provides a video signal including the positive going pulses and the narrow line synchronization pulses and which provides a normal color picture when played on a conventional TV set, the narrow line synchronization pulses each being prior to a color burst in at least one of the horizontal blanking intervals, wherein the narrow line synchronization pulses enhance a copy protection effect provided by the positive going pulses thereby to inhibit recording.