[time-nuts] Z3805 initial behaviour after power up

Ulrich Bangert df6jb at ulrich-bangert.de
Thu Jun 18 02:28:38 EDT 2009


Brian,

> You may also want to search for HP An1279, it also goes over HP 
> smartclock operation, and look for a paper titled "the Global 
> Positioning System and HP SmartClock" by John A. Kusters.

In the meantime I have not only found these but also "Smart Clock: A New
Time" by David Allan et al which shows that "Smart Clock" is originally a
NIST invention & patent and explains very well how it works. Perhaps what I
and You have seen is a direct consequence of applying the Smart Clock
algorithm. 

Best regards
Ulrich


> -----Ursprungliche Nachricht-----
> Von: time-nuts-bounces at febo.com 
> [mailto:time-nuts-bounces at febo.com] Im Auftrag von Brian Kirby
> Gesendet: Donnerstag, 18. Juni 2009 01:51
> An: Discussion of precise time and frequency measurement
> Betreff: Re: [time-nuts] Z3805 initial behaviour after power up
> 
> 
> They do not talk about driving the frequency off, but they 
> warn to keep 
> the receiver locked the first 24 hours, so it can determine how the 
> oscillator ages.  Its in the section on "holdover" (page 52 
> of the PDF , 
> page 3-8 of the user guide).
> 
> You may also want to search for HP An1279, it also goes over HP 
> smartclock operation, and look for a paper titled "the Global 
> Positioning System and HP SmartClock" by John A. Kusters.
> 
> If you have a broadband connection, I can email you each one, if that 
> will help.
> 
> Brian
> 
> Ulrich Bangert wrote:
> > Brian,
> >
> > thanks for your information!
> >
> >   
> >> algorithm.  From what I read about the smart clock, it takes
> >> 5 days for it to complete its initial learning cycle and then its
> >>     
> > continuously
> >   
> >> refining.
> >>     
> >
> > Is that from the Z3801 manual, which I have available, or 
> do you have 
> > any other in depth information source?
> >
> > Best regards
> > Ulrich
> >
> >   
> >> -----Ursprungliche Nachricht-----
> >> Von: time-nuts-bounces at febo.com
> >> [mailto:time-nuts-bounces at febo.com] Im Auftrag von Brian Kirby
> >> Gesendet: Mittwoch, 17. Juni 2009 16:58
> >> An: Discussion of precise time and frequency measurement
> >> Betreff: Re: [time-nuts] Z3805 initial behaviour after power up
> >>
> >>
> >> Ulrich,
> >>
> >> I have two Z3801A and both of them act close to what you
> >> describe in the 
> >> first 24 hours of power up.  I believe its part of the 
> disciplining 
> >> algorithm.  From what I read about the smart clock, it takes 
> >> 5 days for 
> >> it to complete its initial learning cycle and then its 
> continuously 
> >> refining.
> >>
> >> Brian
> >>
> >> _______________________________________________
> >> time-nuts mailing list -- time-nuts at 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 at 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 at febo.com
> To unsubscribe, go to 
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.





More information about the time-nuts mailing list