Hi
> On Apr 25, 2021, at 9:31 AM, Lux, Jim <[email protected]> wrote: > > On 4/25/21 6:02 AM, Bob kb8tq wrote: >> Hi >> >> The thing that I find useful about a GPS simulator is it’s ability to >> calibrate the >> time delay through a GPS based system. In the case of a GPSDO, there may be >> things beyond the simple receiver delay that get into the mix. Getting the >> entire >> offset “picture” all at once is nice thing. Yes, that’s a Time Nutty way to >> look at it….. >> >> So far, I have not seen anybody extending this sort of calibration to the >> low cost >> SDR based devices. Without digging into the specific device, I’m not sure how >> well a “generic” calibration would do. Indeed, it might work quite well. >> Without >> actually doing it … no way to tell. >> >> So if anybody knows of the results of such an effort, I suspect it would be >> of >> interest to folks here on the list. >> >> Bob > > > A double difference kind of relative measurement might be useful - compare > two (or three) GNSS receivers. Then the absolute timing of the test source > isn't as important. Well …. it is and it isn’t. If you are trying to get “UTC in the basement” (or even GPS time) to a couple nanoseconds, then you do need to know absolute delays of a number of things. Is this a bit crazy? Of course it is :) Bob > > _______________________________________________ > time-nuts mailing list -- [email protected] -- To unsubscribe send an > email to [email protected] > To unsubscribe, go to and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] -- To unsubscribe send an email to [email protected] To unsubscribe, go to and follow the instructions there.
