| 摘要 |
PURPOSE: A tuner is provided to use a broadband RF amplifying part and a highly efficient band pass filter without an extra tuning circuit part, and simply realize a channel selecting circuit. CONSTITUTION: An antenna(31) receives signals wirelessly transported. A broadband RF amplifying part(32) amplifies the received RF signals of all frequency bands without tuning the received RF signals. A mixer part(33) converts the amplified RF signals into intermediate frequency signals. A local oscillating circuit part(34) provides specific oscillating frequency to the mixer part. A band pass filter(35) passes only the signals of a set intermediate frequency band. An intermediate frequency amplifying part(36) amplifies the intermediate frequency signals which passed the band pass filter. |
