Patent ID: 7567784

Claim:
A tuner adapted to select a broadcast signal of a selected channel, comprising: an input filter for filtering a received broadcast signal into a plurality frequency bands based on a reference frequency band; a push-pull circuit for amplifying a second signal composing an original phase and being induced by at least one of the frequency bands output by the input filter and for amplifying a first signal comprising an opposite phase of the second signal and being induced by the at least one frequency band output by the input filter and for combining the amplified first and second signals to generate an amplification signal of the signal in the respective frequency bands; the push-pull circuit including a first field effect transistor (FET) for receiving the first signal in a gate terminal and amplifying the first signal according to an amplification degree and a second FET for receiving the second signal in a gate terminal and amplifying the second signal according to the amplification degree; at least one of the first FET and the second FET including a second gate terminal for receiving a control signal controlling the amplification degree; an inter-stage filter for filtering a frequency of the broadcast signal corresponding to a selected channel among the amplification signals output from the amplifier; and a converter in electrical communication with the second gate of the at least one of the first FET and the second FET for converting the broadcast signal of the frequency filtered by the inter-stage filter and for outputting an automatic gain control (AGC) signal controlling at least one of the first FET and the second FET.