A signal receiver (300) has a tuner (301), which receives an RF_IN signal and outputs a desired IF_OUT intermediate frequency signal to a demodulator (311). The demodulator (311), on the basis of the signal level received from the tuner and the AGC characteristic set by a processor (321), controls the RF_AGC and IF_AGC tuner gains. The demodulator operation may also base on the signal level read from the IF_OUT output of the IF_Amp amplifier. The demodulator (311) sends to the processor (321) a digital stream of a desired signal TS. The processor comprises an AGC characteristic controller (327) for calculating the AGC characteristic of the tuner on the basis of a level of the desired signal and a strongest level of close signals, which are detected within the passband of the input filter (101) of the tuner (301) for the desired signal.