| 摘要 |
PURPOSE:To prevent the disapearance of a color at the reproduction of a tape recorded by a different recorder by switching a frequency of an idler signal by means of an output of a frame identification signal detecting circuit. CONSTITUTION:A low frequency converting chrominance signal is led separately by an BPF17 from an output signal of a video head 15, converted into the original chrominance signal frequency by the idler signal CW from a balanced modulator 23 by means of a balanced modulator 18 and applied to a chrominance signal rearrangement circuit 30. Further, an FM luminance signal from an output of the head 15 is demodulated 19, the horizontal synchronism signal is separated and led out 20 so as to generate 21 the phase synchronism signal for PAL/ SECAM and applied to the modulator 23. Further, the presence of the frame identification signal is detected 27 from the output of the BPF 17, its control signal output operates a switching circuit 26 and an output of an oscillator 24 or 25 is given to the modulator 23 so as to change over the frequency of the idler signal CW. |
