| 摘要 |
PURPOSE:To achieve reception with an invariably constant level by common-use receiving facilities, etc., of TV, by decreasing the increment of an output signal level by an attenuator when the channel number of a signal arriving at an input terminal decreases. CONSTITUTION:An attenuating circuit 12 is arranged between an amplifying circuit 2 with AGC and an output terminal 13. Then, an attenuation setting circuit 14 is added to the circuit 12, whose extent of attenuation is so set that when a signal of a less channel number than a prescribed number is inputted to an input terminal 1, the increment of the output signal level of the circuit which corresponds to the decrement in channel number is decreased. When the channel number of the signal arriving at the terminal 1 decreases, the increment of the output signal level of the circuit 2 due to the decrease is attenuated by the circuit 12. Thus, the signal arriving at the terminal 1 is sent out via a terminal 13 with a constant level. |
