* Switch from amplitude based approach to auto-correlation
* Limit the bandwidth of the PLL using a low pass filter
* Reject noise of the PLL using a very steep low pass after it
* Set the loop bandwith of the PLL to a lower value, to get rid off the
DC leakage and improve SNR
* Set the AGC update rate to a higher value
* Decrease the CW decoding threshold
* Set all decoders output to binary format
* Introduce the quadrature demodulation filter in all affected
flowgraphs, in order to reduce false alarms and increase performance