I am trying to build a AM receiver by using USRP. I did setup the IF frequency to 1.43 MHz by using set_rx_freq. I was sending a 1 Khz signal 90% modulated at 1.43 MHz carrier. I should get something from the USRP output just the 1 KHz sine wave. But for some strange reason I am not getting that. I am getting some extra 333 Hz freq signal with it. I dont' know where is the problem. So, I am guessing the NCO-CORDIC is not completely removing my carrier frequency. I saw the waveform just after the USRP it's the same with some extra frequency. Anybody's help and thought would be highly appreciated. Thanks.