摘要 |
A video detector has a PLL, a bias circuit, a synchronous detector for detecting a video IF signal by using the output of a VCO, and a lock detector for detecting whether the PLL is locked. The PLL has the VCO, a phase comparator, and a low-pass filter. In the video detector the supply of the direct current from the bias circuit is halted while said lock detector detects that the PLL is locked.
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