PURPOSE: To realize servo control stable at all times by providing a noise eliminating circuit eliminating noise component exceeding a peak potential of a horizontal synchronizing signal to a front-stage of a clamp circuit constituting a servo control circuit to have only to add a simple circuit.

CONSTITUTION: An output of a video amplifier 5 is inputted to a base of a transistor (TR) Q1 in a noise eliminating circuit 6 and an output is given from the emitter to a clamp circuit 7. When a base potential of a TRQ2 is lower than a base potential of the TRQ1, the Q2 is cut off, and when the base potential of the Q1 is lower than the base potential of the Q2, the Q1 is cut off and Q2 is activated, then a voltage lower than the base potential of the Q2 by a base-emitter voltage of the Q2 appears to each emitter of the Q1, Q2, and when the base potential of the Q2 is set to a proper value by voltage dividing resistors R2, R3, the potential of the horizontal synchronizing signal of the video signal inputted to the base of the Q1 and the base potential of the Q2 are made equal and a noise having a level lower than the potential of the horizontal synchronizing signal is not outputted to the clamp circuit 7.