| 摘要 |
PURPOSE:To prevent the deterioration in S/N of a reproducing luminance signal and the occurrence of the beating at a reproducing luminance signal by preventing the mixing of a reproducing conveying chrominance signal system output at a reproducing luminance signal when a reproducing conveying chrominance component is not generated. CONSTITUTION:At the time of reproducing the white black video signal of a magnetic tape 1, conveying chrominance components are not removed from a BPF11. In the burst period, the burst signal of the prescribed level or above is not obtained from a BPF17, a detecting signal-ACK of an automatic color detecting circuit 25 comes to be a low level, to an or circuit 26, a high level burst flag BFLG is supplied, a control signal Ss comes to be a high level during the burst period only, and a changing-over switch 21 is connected to an A side. An automatic color killer circuit 23 comes to be the action condition, the output of the BPF17 is not supplied to an adder 16, and to an output terminal 18, a black white video signal is derived. The output of the BPF11 is not supplied to an adder 7 excluding the burst period, and therefore, the noise due to the full gain of an ACC circuit 10 is not mixed into a reproducing luminance signal by the adder 7.
|
