| 摘要 |
PURPOSE:To obtain a television image receiving circuit suited for an integrated circuit by constituting a noise erasure circuit, which detects a noise component included in a video detection signal and erases noise,of an emitter follower transistor. CONSTITUTION:A radio wave from an antenna 1 is inputted to a video detection circuit 4 through a tuner 2 and a video intermediate wave amplifier, and a composite video signal can be obtained. An AGC circuit 6 compares the peak value of the composite video signal with a reference value obtained by voltage- dividing a power source 8, and controls the tuner 2 and the amplifier 3 so that both values can be the same. Normally the output of the circuit 4 is outputted to a terminal 11 through an output switching circuit 10 in a noise erasure part 7. If noise over a threshold voltage 12 gets in, a noise detection circuit 13 detects the noise, and outputs the output voltage of a level shift circuit 14 to the terminal 11 through the circuit 10. Thus some of noise included in the input signal can be clamped at a fixed voltage, and therefore the noise can be erased.
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