Hi On a Time Nut metaphysical note -
> On Jun 25, 2018, at 10:38 AM, Tom Van Baak <t...@leapsecond.com> wrote: > > Steve, > >> I need the rising edges of both the 10 MHz and 100 MHz squarewave outputs >> to be aligned with the GPS 1 pps (UTC) to within 1 ns. > > Two comments. > > 1) If you divide 100 MHz -> 10 MHz -> 1 Hz then (with careful design, > calibrated layout / wiring) you can have all three rising edges within 1 ns > *of each other*. I assume this is your goal. If you already have a 100 MHz > GPSDO then it would surprise me if the outputs are not already synchronized > with each other. I mean, almost all GPSDO give a 1PPS output that is derived > from the LO, by design. If your goal is 1 ns, you obviously do not want to > use the raw 1PPS from the receiver. What make/model GPSDO are you using? > > 2) On the other hand, if your goal is that all the outputs are within 1 ns > *of UTC*, then you have a big problem. Not even national timing laboratories, > with a pile of cesium and H-maser references, can get their UTC(k) within 1 > ns of UTC. Perhaps you can explain a bit more what you are actually doing. It > sounds like an interesting application. Relative timing at the 1 ns level is > easy. Absolute UTC timing at the ns level is much, much harder. Does UTC exist ( real time ) at the 1 ns level? Bob > > /tvb > > ----- Original Message ----- > From: "Martyn Smith" <expertengin...@live.co.uk> > To: <time-nuts@lists.febo.com> > Sent: Sunday, June 24, 2018 3:37 AM > Subject: [time-nuts] 1 pps Sync'ing > > >> Hello, >> >> I am a newbie question. >> >> I have an application where I have a 10 MHz and 100 MHz squarewave output >> from my GPS frequency standard. >> >> The frequency standard uses the PRS10 rubidium. The 100 MHz output is just >> a 100 MHz VCO locked to the 10 MHz. >> >> These outputs are disciplined by the GPS's 1 pps (as far as frequency). But >> they are not in phase with it. >> >> I need the rising edges of both the 10 MHz and 100 MHz squarewave outputs to >> be aligned with the GPS 1 pps (UTC) to within 1 ns. >> >> Anyone already done this? I'm sure I've seen a distribution amplifier that >> does this at 10 MHz. >> >> But the 100 MHz is actually the more important one that I need to align. >> >> Regards >> >> Steve >> _______________________________________________ >> time-nuts mailing list -- time-nuts@lists.febo.com >> To unsubscribe, go to >> https://lists.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > https://lists.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to https://lists.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.