<p><P>PROBLEM TO BE SOLVED: To provide a signal generator suitable for surely presetting only the channel of a specified frequency band in initial scan or re-scan. <P>SOLUTION: The signal generator (2) includes: a signal input part (10) for inputting terrestrial digital broadcasting signals of a frequency band corresponding to a channel 13 to a channel 62 which are the physical channels of terrestrial digital broadcasting; a sweep signal generator (14) for periodically generating sweep signals for selectively degrading the signal quality of the broadcasting signals of the specified frequency band; and a mixing means (13) for mixing the terrestrial digital broadcasting signals input to the signal input part and the sweep signals output from the sweep signal generator. The mixing means (13) outputs the terrestrial digital broadcasting signals in which the signal quality of the broadcasting signals of a specified physical channel is selectively degraded. <P>COPYRIGHT: (C)2010,JPO&INPIT</p>
