| 摘要 |
PROBLEM TO BE SOLVED: To limit recording of a video signal in a video tape recorder recording an analog video signal via an analog interface. SOLUTION: A burst signal b is subjected to band limitation via a recording system and a reproduction system of a VCR, the signal is unsharpened, and the skirts of the signal is spread as shown in a signal b'. When a signal c whose characteristic differs from that of the signal b is located in the vicinity of the signal (b), as shown in the part d, both the signals are interfered with each other by the unsharpened signal due to the band limit and the number of waves of the signal b is substantially reduced. In the case of recording/ reproducing the video signal in which a copy prevention signal is located by the VCR, the ACC of the VCR is not normally operated and image disturbance is caused thereby realizing copy guard. On the other hand, since a frequency band of the color signal is taken to be sufficiently wide in a TV, it is not required to apply low frequency conversion of the color signal. Even when the video signal is reproduced, no image disturbance is caused. |
