Television receiver, channel tuning method and channel scan method

A television receiver comprising:

• a reception unit to receive a cable television broadcast signal;
• a first storage unit to store a frequency table of the cable television broadcast signal received by the reception unit in a channel tuned in just before;
• a second storage unit to store a modulation method of the cable television broadcast signal received by the reception unit in each of channels obtained by auto scans;
• a tuning unit to tune in a channel;
• and
• a reception control unit to set channel data composed of a combination of the frequency table stored in the first storage unit and the modulation method stored in the second storage unit, the modulation method corresponding to the tuned channel, as channel data of a cable television broadcast signal corresponding to the tuned channel when the channel is tuned in by the tuning unit, and to make the reception unit receive the cable television broadcast signal corresponding to the tuned channel, wherein
• the reception control unit judges whether reception of the cable television broadcast signal has succeeded or not by setting the channel data composed of the combination of the frequency table stored in the first storage unit and the modulation method stored in the second storage unit, the modulation method corresponding to the tuned channel, and the reception control unit sequentially changes the channel data to be set in a previously determined order to make the reception unit receive the cable television broadcast signal corresponding to the tuned channel when the reception control unit judges that the reception of the cable television broadcast signal has not succeeded, and subsequently, the reception control unit updates the frequency table stored in the first storage unit and the modulation method stored in the second storage unit, the modulation method corresponding to the tuned channel, to the frequency table and the modulation method that are included in the channel data set at a time of the success, respectively, when the reception control unit judges that the reception of the cable television broadcast signal has succeeded.

A television receiver comprising:

• a reception unit to receive a cable television broadcast signal;
• an auto scan unit to perform setting channel data composed of a combination of a frequency table and a modulation method of the cable television broadcast signal received by the reception unit to each channel at a predetermined timing;
• and
• an auto scan storage unit to store the channel data composed of the combination of the frequency table and the modulation method of the cable television broadcast signal received by the reception unit in a channel tuned in just before at a time of an auto scan of the auto scan unit, wherein
• the auto scan unit is provided with an auto scan reception control unit to set the channel data stored in the auto scan storage unit as channel data of a cable television broadcast signal corresponding to a tuned channel to make the reception unit receive the cable television broadcast signal corresponding to the tuned channel when the channel is tuned in, wherein
• the auto scan reception control unit judges whether reception of the cable television broadcast signal has succeeded or not by setting the channel data stored in the auto scan storage unit, the auto scan reception control unit sequentially changing channel data to be set in a previously determined order to make the reception unit receive the cable television broadcast signal corresponding to the tuned channel when the auto scan reception control unit judges that the reception of the cable television broadcast signal has not succeeded, the auto scan reception control unit subsequently updating the channel data stored in the auto scan storage unit to channel data set at a time of a success when the auto scan reception control unit judges that the reception of the cable television broadcast signal has succeeded.