An apparatus and method are disclosed for scanning and detecting defects in sewer and similar pipelines that eliminate the need to stop and pan-and-tilt areas of concern. Using an input peripheral associated with a computer terminal, a code associated with the medical instrument to be subjected to a cleaning operation after a previous use of the medical instrument is received. A bias voltage is applied across the other end of the first switching element and the other end of the second switching element, and a trigger pulse is input from the first and second pulse input terminals.