Hi You can telnet into the 5125 to get longer data plots. It's a royal pain to do. You then need to run the data through something like TimeLab or Stable32 to turn it into ADEV.
I think you will find that *if* the temperature in the draft is stable, the ADEV hit will settle out. It'll take longer than the simple return to frequency. Bob -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Said Jackson Sent: Thursday, December 20, 2012 11:47 AM To: Discussion of precise time and frequency measurement Cc: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Z3805A cooling requirements? Bob, The ADEV plot was done after the unit had fully settled to it's new location in front of the 53132A fan. The Tsc5125A instrument has a limit of 9 minutes to plot the frequency drift for some reason, so I can only show you the last 9 minutes. The transient due to the new temperature was long gone when I started this ~20 min ADEV plot. Bye, Said Sent from my iPad On Dec 20, 2012, at 4:36, Bob Camp <[email protected]> wrote: > Hi > > Did I miss part of the data? > > The plot I got shows about 9 minutes. Temperature step stress takes a *long* time to settle out. > > Bob > > On Dec 19, 2012, at 9:56 PM, [email protected] wrote: > >> Not sure about that, if you look at the frequency plot after ~20 minutes in >> moving air the frequency was still extremely close to 10.000000MHz.. to >> within <1E-011 of 10MHz. This is a free-running 10811. >> >> Compare that to the plot of the OCXO I had sent out some hours ago when it >> was running stable inside the foil - there was almost no average frequency >> change between the two tests. >> >> If the heaters had an issue keeping average crystal temperature stable, >> then the frequency would have changed from the first plot to the last plot I >> would think. In my opinion the airflow is just adding a huge bunch of heater >> control loop noise to the output stability, or there are components on the >> PCB which are very sensitive to the airlfow. Consider that this unit and >> it's PCB was designed to live inside the 53132A (very close to the fan) that >> I am now using as an air source. One thing this tells me: the fan in the >> counter could be disabled and it would improve the units stability, if one >> keeps an eye on internal counter temperature. >> >> bye, >> Said >> >> >> In a message dated 12/19/2012 18:42:08 Pacific Standard Time, >> [email protected] writes: >> >> I think the data shows that the heaters were losing ground, which would >> explain the steadily falling temp of the SC cut quartz. >> >> Thomas Knox >> >> >> >> _______________________________________________ >> time-nuts mailing list -- [email protected] >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
