Hi Piotr,
And do you set both the Clock and Time source to the external ones when using it in that configuration ? I just had a look at both the schematic and VHDL and there is actual switches ... the GPSDO 10M and PPS should basically be completely disconnected when the reference for time and clock is external. Also, are you using an external power supply ? Maybe the issue is the added load on the supply rails when the GPSDO is plugged in. Cheers, Sylvain _______________________________________________ USRP-users mailing list USRP-users@lists.ettus.com http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com