BS TUNER

摘要

PURPOSE: To provide a BS tuner which can automatically supply power to an LNB with no switch operation. CONSTITUTION: A C/N detection part 1b detects the BS-IF signal that is inputted to a demodulation part. A C/N decision part 1c outputs the digital value '1' and '0' when the C/N larger than the prescribed value is detected and not detected respectively based on the detection information of the part 1b. Then an output control part 1d supplies no power to a BS antenna 2 and supplies power to an LBN 3 when the output of the part 1c is equal to '1' and '0' respectively based on the output information of the part 1c. Thus it is possible to automatically decide whether the power should be supplied to the LBN 3 just by switching on the power supply of a BS tuner 1.