DISTORTION COMPENSATION AMPLIFIER WITH BYPASS FUNCTION

PROBLEM TO BE SOLVED: To reduce number of times of complete down-state of a line resulting from stopping an amplifier function when a distortion compensation operation is faulty due to a faulty distortion compensation amplifier. SOLUTION: A bypass cable 15 is provided to couple inputs directly and changeover devices SW1, SW2 are provided to input output sections. A control circuit 14 monitors an output of an error signal detector 12 and a pilot signal receiver 13, provides a control signal (a) to a changeover control circuit 16 when the output indicates an error, and the changeover control circuit 16 throws the SW1, SW2 to the position of the bypass cable 15 so that an input signal is used for an output signal as it is.