Hello GNURadio Community, I am having trouble getting the PLL Carrier Tracking Block to work properly. I designed the GRC with a qpsk constellation modulator at a sample rate of 40 k Hz. I designed the PLL Carrier Track block to correct incoming waveforms that are off centered from DC by +/-500 Hz (setting max/min freq with the formula +/-2*pi*f(=500)/samp_rate). The eye test at the PLL outputs seems to show that the input signal freq is recentered around DC, however, the signal level coming out of the PLL is greatly reduced and appears to be smeared. So obviously, when I follow this block with a Symbol Sync block it does not lock and the constellation points continue to rotate.
Will appreciate any help to guide me in the right direction. Thank you! Regards, George
