| 摘要 |
PROBLEM TO BE SOLVED: To provide a digital audio broadcast receiver for receiving plural band signals in which the configuration of a high frequency circuit is simplified. SOLUTION: An RF amplifier 9 is provided for amplifying an input signal in a first band of a high frequency. A first frequency conversion circuit consisting of a mixer 10 and a local oscillator PLL 11 is provided for converting the output of this amplifier 9 to a signal in a second band of a low frequency. An RF amplifier 4 is provided for amplifying the signal in the second band and an AGC circuit 7 is provided for frequency converting the output of this amplifier 4 by the mixer 10 and a local oscillator PLL 6 to lead-out a first intermediate frequency signal and AM-detecting the output of the amplifier 4 to output AGC voltage. A voltage converting part 8 is provided for adjusting the gain of the amplifier 4 by the AGC voltage and converting the AGC voltage to generate converting AGC voltage for controlling the gain of the amplifier 9.
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