Abstract: In order to effectively demodulate an incoming RF signal which takes the form of bursts in a satellite communications system using a Single Channel Per Carrier Demand Assigned Multiple Access (SCPC-DAMA) technique, a controller is provided which is operatively coupled to a down-converter and a demodulating section. In the event that the RF signal is a continuous signal, the controller routes an AGC signal, which is outputted from the demodulating section, to a first variable attenuator provided in the down-converter and applies a constant potential to a second variable attenuator within the demodulating section. On the other hand, in the event that the RF signal assumes the burst format, the controller retains a value of the AGC signal at the time when the RF signal undergoes the continuous-burst change and applies the retained value of the AGC signal to the first variable attenuator.