| 摘要 |
PROBLEM TO BE SOLVED: To provide a radio tuner capable of accurately detecting a signal level.SOLUTION: A radio tuner comprises an S meter 102 detecting electric field that includes an auto gain controller 44 automatically adjusting a gain, an RF amplifier 30 dividing an input signal by the gain set by the auto gain controller 44, a post-stage circuit (a mixer 32, an IF amplifier 34, and an IF band-pass filter 36) processing an output signal from the RF amplifier 30, a gain control level detector 46 detecting the gain set by the auto gain controller 44, and a multiplier 50 multiplying a signal processed by the post-stage circuit by the gain detected by the gain control level detector 46. |
