| 摘要 |
PURPOSE:To improve tone quality at the time of receiving an AM stereophonic broadcast by selectively switching a wide band and a narrow band by switching a switch. CONSTITUTION:The switch 28 which switches the output side of a wide band filter 27 is provided, and a transit terminal 29 is connected to a contact 31 in case of the wide band and it is connected to a contact 30 in case of the narrow band. In order to obtain the intermediate frequency signal of the wide band, an input signal converted by a frequency converting unit 25 is fetched through a tuning coil 26 and a wide band filter 27 and amplified in an intermediate frequency amplifier 34. Meanwhile, in order to obtain the intermediate frequency of narrow band the intermediate frequency signal is inputted in an amplifier 32 through the wide band filter 27 and after amplifying only attenuation quantity of the wide band filter 27 it is impressed on the intermediate frequency amplifier 34 through a narrow band filter 33 so as to be amplified. Thus, separation in terms of alternating current between the wide band filter 27 and the narrow band filter 33 is improved and especially the reception with high tone quality can be possible at the time of receiving the AM stereophonic broadcast.
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