Yes: We only use one streamer for all RF outputs, and send time_spec with each call to the streamer's send method. We reset the internal time with set_time_unkown_pps(0), and program the first samples to be streamed at a time of 0.800s. It is basically the same code we used on the X300/X310.
Thanks, Serge On Wed, 7 Nov 2018 at 21:03, Marcus D. Leech via USRP-users < usrp-users@lists.ettus.com> wrote: > On 11/07/2018 08:53 PM, Serge Malo via USRP-users wrote: > > Hi all, > > We are trying to send 4 synchronous signals from the 4 Tx ports of the > N310. > We are using UHD 3.13.1.0 RC1 under Ubuntu. > Central Freq = 1575.42 GHz and 1227.6 MHz > Master Clock rate = 153.6 MHz > > We would expect to have less than 3ns offset between all TX ports of the > N310, like we do with the X300/X310. However, we have measured 4700ns > between TX RF ports 0 and port 2. > We have tried the next things with no more success: > - Sampling rates of 25.6MSps, 38.4Msps, 76.8Msps > - Init with the device options "init_cals=ALL" and "force_reinit=1" > - Use the internal GPSDO > - Use clock_source=external and time_source=external (from an Octoclock). > > Can you tell us: > -What time offset between TX RF ports we should expect to achieve? > -Is there anything else we can try to reduce this offset to less than 3ns? > > Best regards, > Serge > > > How are you setting up your TX streamer? Is it time-tagged to start at a > particular device time? > > > > _______________________________________________ > USRP-users mailing list > USRP-users@lists.ettus.com > http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com >
_______________________________________________ USRP-users mailing list USRP-users@lists.ettus.com http://lists.ettus.com/mailman/listinfo/usrp-users_lists.ettus.com
