| 摘要 |
PURPOSE:To prevent beat interference between the horizontal scanning frequency component in television audio signal and its harmonics, by setting the clock oscillation frequency of delay elements to (2n+1)/2 times the horizontal frequency. CONSTITUTION:The monaural delay element 3M having many stages and the stereo delay element 3S having less stages are connected in parallel, the outputs are added to the switching circuit 8, and the output of either one of the delay elements 3M, 3S is picked up with switching by means of the stereo control signal. The clock pulse for drive is fed to both elements 3M and 3S from the clock oscillation circuit 4. The frequency of clock pulse is set to (2n+1)/2 of the horizontal frequency fH. Thus, the beat components of an integer multiple of fH/2 in the interference among the horizontal frequency component in television audio signal, its harmonics, clock pulse and its harmonics can only be produced. |
