| 摘要 |
<p>A tuner unit (1) generates a local oscillation signal for multiplication by a received first IF signal and then for conversion in frequency, and converts the frequency-converted signal into a base band signal. A demodulation unit (2) detects a demodulated data signal level for reporting to a control unit (3). The control unit (3) compares the signal level reported from the demodulation unit (2) with a reference value stored in a storage unit (4), and, when the signal level is below the reference value, has the tuner unit (1) change an oscillation frequency of a local oscillation signal used for frequency conversion of the first IF signal and selects a channel in the next frequency range. Therefore, all the broadcasting bands can be scanned in a short time for a quick channel selection and time required before starting a service can be reduced.</p> |
