Hi Tom: If you look at the plot I attached as a .pdf you can see that the current slope looks like a nice straight line covering almost 4 days so temperature is not a factor. The only factor I can think of is magnetic field. I guess the next step is to rotate the box 90 degrees and see what happens unless there's some other suggestions.
I haven't got the automatic logging started yet, but it's in process. Have Fun, Brooke Clarke http://www.prc68.com/P/Prod.html Products I make and sell http://www.prc68.com/Alpha.shtml All my web pages listed based on html name http://www.PRC68.com http://www.precisionclock.com http://www.prc68.com/I/WebCam2.shtml 24/7 Sky-Weather-Astronomy Web Cam Tom Van Baak wrote: >> Hi: >> >> I've been looking at the 4065B Cesium standard vs. GPS this month. After >> the >> plot showed a slope of 472E-15 the frequency offset was changed from zero to >> 472 on 8 May (gambling on the sign). For the next couple of days the points >> all were in a box 20 ns high. BUT then the slope changed. It's now got a >> positive slope that's very close to 472E-15 and the frequency offset is at >> 472 >> not zero. See attached plot. >> >> What might be causing this? For example the 4065B is just sitting on a >> chest >> of drawers and might be moved or rotated a little from time to time. Is >> there >> a requirement that it be in a temperature controlled room on a concrete >> pillar >> to get into the E-14 area? >> >> It just turns on better than 5E-13 and the attached plot seems to indicate >> that >> it and be manually adjusted to parts in E-14 but so far I've not been able >> to >> do that. > > Brooke, > > At the level of e-14 and e-15 you might need weeks of data to > separate the normal flicker noise from any clear frequency > offset or drift trends. Yes, it's quite possible that environmental > effects are also polluting your data. You can either control > temperature, or just collect temperature data and see if there > is a correlation with your standard. > > Do you have a continuous set raw GPS-Cs 1PPS data that I > can look at to see if I can help you? > > /tvb > > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.