| 摘要 |
PROBLEM TO BE SOLVED: To obtain an automatic gain controller, capable of surely operating with respect to a dubbing prevension signal and suppressing malfunctions due to a video signal, to which a dubbing prevension signal is not impressed or a video signal of which quality is deteriorated. SOLUTION: This controller is constituted such that independently of a 1st automatic gain control(AGC) circuit 12 for executing gain control operation in response to a dubbing prevension signal, a 2nd AGC circuit 14 which does not respond to a dubbing prevension signal is prepared, a synchronizing signal is separated from an output from the AGC circuit 14 and supplied to the 1st and 2nd AGC circuits 12, 14 as a gate signal to execute respective gain control operation. |
