| 摘要 |
PURPOSE:To make it possible to delay a reproducing FM signal of wide frequency band with an existing delay circuit by converting the reproducing FM signal to an FM signal with a high carrier-frequency at a frequency conversion circuit and making the frequency-modulated high frequency FM signal to delay for 0.5 horizontal period at the delay circuit. CONSTITUTION:A reproducing FM signal which is reproduced from a rotary magnetic disk 1 by a reproducing head 2 is inputted to the one side of the input terminal of a frequency conversion circuit 12 and a signal with a single frequency f0 from a reference signal source 11 is inputted to the other side of the input terminal and from the frequency conversion circuit 12, the reproducing FM signal of the difference frequency of these two signals is outputted. In the period that the picture of the second field is reproduced, the high frequency reproducing signal that is delayed for 0.5 horizontal period at a delay circuit 4 is inputted to a video signal demodulating circuit 6 and by demodulating the signal, a video signal of the second field is obtained. Assuming that the carrier-frequency of the reproducing FM signal that is made to delay at the delay circuit 4 is 14mHz, the passband of the delay circuit 4 is enough to be 14+ or -4mHz.
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