| 摘要 |
PURPOSE:To execute a scramble having small scramble information and large disturbance in a circuit by executing the inherent scramble to the sections of horizontal synchronizing signals, color burst and video signals respectively. CONSTITUTION:Horizontal and vertical synchronizing signals separated from video signals by a synchronizing separator circuit 2 are inputted to a scramble control circuit 3. The control circuit 3 generates the random numbers of 0-8, and determines whether gain restriction is to be made or not to the sections of horizontal synchronizing signals, color burst signals and video signals based on the random number, and controls a gain control circuit 6, and at the same time, superposes the random number in the vertical fly-back lines as scramble information. Since the scramble is made in each section according to making or not making a fixed gain restriction, the circuit is made simple, and scramble information is lessened and the deterioration of signals is reduced. As scramble is made to each section respectively, the degree of disturbance to wrong receiving is large. |
