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.
