PURPOSE: To automatically remove a dispersal signal by providing an adding means before a clamp means, and adding an inverted triangular wave signal whose level is equivalent to that of the dispersal signal to an MUSE signal.

CONSTITUTION: An input MUSE signal is soft clamp-processed by a clamp circuit 2, and the output is converted into digital data by an A/D converter 4. Then, a transmission control signal is separated from the data by a transmission control signal circuit 10, and the presence or absence of the dispersal signal is detected by a dispersal signal detecting circuit 11. At that time, when the dispersal signal is superimposed, a field pulse generating circuit 12 generates a pulse phase-synchronizing with the dispersal signal. Then, an inverted triangular wave signal generating circuit 13 integrates the field pulse, and generates a triangular wave signal of an inverse polarity. An adding circuit 9 provided before the circuit 2 adds the inverted triangular wave signal whose level is equivalent to that of the dispersal signal to the MUSE signal. Then, the dispersal signal is automatically removed by the corresponding triangular wave.