PURPOSE: To make unnecessary the adjustment of frequency characteristics and the usage of filters and to prevent the deficiency of video quality, by holding the output of the relay unit for video as well as audio at constant level, when the level of the audio carrier is fluctuated due to fading or the like.
CONSTITUTION: The signal fed to the input terminal A is outputted to the output terminal B via the gain adjusting circuit 1, tilt adjusting circuit 2 and branch circuit 3. Further, a part of the output is picked up from the circuit 3 and it is fed to the detection circuits 4 and 5 to pick up separately only the carrier and audio carrier and they are fed to the comparison control circuit 8 via the detection circuits 6 and 7. Further, the tilt adjusting circuit 2 is controlled so that the output difference between the video carrier and audio carrier can be specified value with the control circuit 8. On the other hand, the video carrier signal picked up with the detection circuit 4 is detected with the detection circuit 6 and is fed to the gain control circuit 9. The gain adjusting circuit 1 is controlled with the output of the circuit 9 to make unnecessary the adjustment of the frequency characteristics and the usage of filter.
ANDOU MASAAKI
OOKAWA SHINJI
