PURPOSE: To facilitate an inspecting process and to attain automation easily, and to standardize an inspection reference by inspecting the operation of a DC circuit while making a shift in television broadcasting frequency.

CONSTITUTION: A signal H is outputted from the output terminal (a) of the TV signal control part 5a of an inspection controller 5 and a test pattern of reference frequency is transmitted by a TV signal generator 4 and tuned by a TV receiver 3; and a signal L is outputted from the output terminal (a) and a test pattern of inspection frequency shifted by ±100kHz is transmitted by the TV signal generator 4. Then, a signal H is outputted from the output terminal (b) of a DC (AFT) switch control part 5b to turns on the AFT switch of a TV receiver 3 through an AFT switch controller 6. Then, leading-in operation is performed as long as the AFT circuit is normal to make tuning corrections automatically, so a video intermediate frequency is outputted and the decision device 5c of the inspection controller 5 decides on it to output a signal H to its output terminal (d), so that a display device 11 outputs it to an annunciating means which shows acceptance.