| 摘要 |
PURPOSE:To obtain a stable chrominance signal not causing missing of color of a reproduced picture by making the gain of a frequency discriminator variable, decreasing the gain at the special reproduction so as to lower the level of a discrimination output signal from the normal reproduction. CONSTITUTION:A reproduced mode signal (h) is set to a low level in case of the normal reproduction and set to a high level in case of the special reproduction such as fast forward reproduction of rewinding reproduction. The gain of the frequency discriminator 2 is increased when the reproduction mode signal (h) is at a low level and decreased when the signal is at a high level. In case of the special reproduction, the level of a discriminated output signal (c) is smaller than that at the normal reproduction depending on the signal (h) and the fluctuation of the oscillated frequency of a VCO 1 is decreased. As a result, even when a reproduced horizontal synchronizing signal (a) is inputted intermittently and the frequency is fluctuated largely than that at the normal reproduction resulting from the special reproduction, the oscillated frequency of the VCO 1 is not largely fluctuated by those causes and a reproduced picture without missing of color is obtained while keeping its stability.
|
