[Discuss-gnuradio] USRP2 1pps synchronization delay

[Kelley, Clifford W]

We are trying to determine how much delay there is between the 1pps pulse and 
when the samples come out properly time tagged.  Using a GPS timing receiver we 
connected up the 10MHz clock and 1pps to the USRP2.  The software is set up to 
reset on the next 1pps pulse.  With a GPS software receiver we determined that 
there is a delay of 3 - 6 microseconds which curiously was 3 with a smaller 
decimation and 6 at a higher decimation.  We've checked over the setup and 
can't find any reason for this.  Does anyone have any ideas?

Thanks,

Cliff