Thank you very much Markus

The .USR file is useful, but your detailed explanations are even better to understand what's going on

Would worth to add it to your EbNaut utilities

So far so good. SL is "armed" and working on the next FFT in a few hours

Yes. Patience is a must when you play with high integration FFTs. This is not a game for nervous players ;-)

I was using 192Khz sample rate but have changed to 48KHz to fit with your decimation and FFT lenght

The 1pps syncronization is working good and the SR is adjusted properly. I get the NMEA via com port

and system is reported by SL to be just few mili seconds from GPS 

All ready here to receive a transmission !

73 de Luis

EA5DOM