My starting point is the paper by Neubig on the real vs. predicted aging: experimenting with the model and try to cut it around the Morion or the Oscilloquartz OCXOs.
On Tue, Aug 28, 2012 at 12:15 AM, Don Latham <[email protected]> wrote: > There are ways of generating models, such as ARIMA, using past behavior > and the models used to tweak filters and so on. The shifts would have to > be accounted for as they occur, seems to me. Now the interesting > possibility is that a shift does not alter the underlying model for a > given crystal???? > Has to be tested. > Don > > Azelio Boriani > > So it can't be done... the possibility to discipline an OCXO taking the > > action from a suitable model should help in speeding up the adjustments > > and > > avoiding the humps as seen in the Allan deviation plot. > > > > On Mon, Aug 27, 2012 at 9:31 PM, Don Latham <[email protected]> wrote: > > > >> Isn't crystal aging marked by random jumps? perhaps lattice > >> rearrangement? Really hard if not impossible to model... > >> Don > >> > >> Azelio Boriani > >> > 30mV are -13dBm so maybe it is why the -20dBm is not a suitable > >> level > >> > for > >> > that input. I have the 53132A and the 53181A so I can test (with the > >> R&S > >> > SML01). Is this problem new? Never tested before? > >> > > >> > About the OCXO aging: OK, I'm interested in the development of a > >> model > >> > that > >> > can be general enough so that it can be "steered", adjusting its > >> > parameters, during the OCXO life. The data (to adjust the > >> parameters) > >> > will > >> > be gathered by the continuous monitoring with the GPS. > >> > > >> > On Mon, Aug 27, 2012 at 7:01 PM, Bernd Neubig <[email protected]> > >> > wrote: > >> > > >> >> Hi Azelio, > >> >> > >> >> Sorry, the counters are 53131A, not 53151A. The A and B inputs are > >> >> specified > >> >> from DC to 225 MHz with a sensitivity of y20 mV (rms) up to 100 > >> MHz, > >> >> <30 mV > >> >> (rms) 100 ~ 200 MHz, and <50 mV (rms) 200 ~ 225 MHz. > >> >> The problem can be at either input alone. The problem is only in > >> the > >> >> range > >> >> between 100 MHz and <200 MHz, observed in automatic trigger mode. > >> In > >> >> manual > >> >> trigger mode the counter does not trigger at all in that freq > >> range. > >> >> > >> >> I cannot tell you an aging model for a particular OCXO, and I doubt > >> if > >> >> anyone can ;) Aging predictions can only be made on individual > >> OCXO, > >> >> unit > >> >> by > >> >> unit, and the prediction is only valid over a rather limited time. > >> >> Therefore > >> >> you must continuously monitor and update your prediction. > >> >> > >> >> Best regards > >> >> > >> >> Bernd > >> >> DK1AG > >> >> > >> >> -----Ursprüngliche Nachricht----- > >> >> Von: [email protected] [mailto:[email protected]] > >> Im > >> >> Auftrag von Azelio Boriani > >> >> Gesendet: Freitag, 24. August 2012 17:28 > >> >> An: Discussion of precise time and frequency measurement > >> >> Betreff: Re: [time-nuts] HP/Agilet counter 53151A trigger problems > >> >> > >> >> From the datasheet: > >> >> A input 10Hz..125MHz min level 25mVrms (-19dBm) B input min 50MHz, > >> >> -20dBm > >> >> the problem is on A input only? Maybe 150MHz for the A input, being > >> >> beyond > >> >> the official specifications, requires more signal on one counter > >> than > >> >> the > >> >> other. In the past they all were fine? > >> >> I have read your paper on the correlation between the real and > >> >> predicted > >> >> aging of crystal oscillators. I'm trying to find a suitable model > >> for > >> >> the > >> >> Morion MV201 OCXO or the Oscilloquartz 8663 to implement a Kalman > >> >> filter. > >> >> > >> >> On Fri, Aug 24, 2012 at 3:34 PM, Bernd Neubig <[email protected]> > >> >> wrote: > >> >> > >> >> > Hi all, > >> >> > > >> >> > I have several HP/Agilent frequency counters 53151A (and 53152A) > >> in > >> >> my > >> >> lab. > >> >> > Several of them meanwhile show trigger problems. > >> >> > > >> >> > I have tested the A and B channel between 5 MHz and 200 MHZ at > >> three > >> >> > input levels of -10 dBm, 0 dBm and +10 dBm. > >> >> > > >> >> > Those with trigger problems show erroneous numbers at -10 dBm > >> input > >> >> > level rather selectively, i.e. mostly at 100 MHz, some also at > >> 150 > >> >> > MHz, while the are o.k. > >> >> > > >> >> > Has anyone on this list experienced similar defects and can give > >> a > >> >> > recommendation how to fix/repair them? > >> >> > > >> >> > > >> >> > > >> >> > Best regards > >> >> > > >> >> > > >> >> > > >> >> > Bernd > >> >> > > >> >> > DK1AG > >> >> > > >> >> > www.axtal.com > >> >> > > >> >> > _______________________________________________ > >> >> > 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. > >> > > >> > > >> > >> > >> -- > >> "Neither the voice of authority nor the weight of reason and argument > >> are as significant as experiment, for thence comes quiet to the mind." > >> R. Bacon > >> "If you don't know what it is, don't poke it." > >> Ghost in the Shell > >> > >> > >> Dr. Don Latham AJ7LL > >> Six Mile Systems LLP > >> 17850 Six Mile Road > >> POB 134 > >> Huson, MT, 59846 > >> VOX 406-626-4304 > >> www.lightningforensics.com > >> www.sixmilesystems.com > >> > >> > >> > >> _______________________________________________ > >> 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. > > > > > > > -- > "Neither the voice of authority nor the weight of reason and argument > are as significant as experiment, for thence comes quiet to the mind." > R. Bacon > "If you don't know what it is, don't poke it." > Ghost in the Shell > > > Dr. Don Latham AJ7LL > Six Mile Systems LLP > 17850 Six Mile Road > POB 134 > Huson, MT, 59846 > VOX 406-626-4304 > www.lightningforensics.com > www.sixmilesystems.com > > > > _______________________________________________ > 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.
