| 摘要 |
PURPOSE:To achieve high-density and skew-distortion-free special reproduction on a PAL and a SECAM system by delaying successively and recording a color signal on a magnetic tape with a specific time difference different in every constant period. CONSTITUTION:A luminance signal, after passing through an LPF2, is modulated by a frequency modulator 4 and the modulated signal is added to a color signal by an adder 6. An output chrominance carrier signal from a BPF3, on the other hand, is led to terminals (a)-(d) of a switch circuit 17 via 0.5H-1.5H delay lines. Connections of the circuit 17 are changed by frequency division outputs 24 and 25 of a head changeover signal 23. The output of the switch 17 is supplied to the adder 6 via a frequency converter 5 and adders 18 and 19. Then, color signals of alternate tracks are recorded on the magnetic tape in order. In reproduction, on the other hand, output signals are obtained by being delayed successively with time differences inverse of those in recording. For special reproduction, discontinuous points of a reproduced horizontal synchronizing signal are detected, and the delay times are changed by control signals obtained from the detection signals. |
