| 摘要 |
An AFT circuit achieves automatic fine tuning by use of an AFT voltage obtained by a F/V converter through its F/V conversion of an output from a VCO that is controlled by a PLL circuit to operate in synchronism with a video carrier included in a television signal supplied from outside. The center frequency of the VCO is shifted by adding the AFT voltage to an output signal from the phase comparator of the PLL circuit in order to obtain a wider capture range for automatic fine tuning. |
