[time-nuts] 60hz disciplined watch

paul swed paulswedb at gmail.com
Wed Apr 20 15:23:02 UTC 2011


Thats what I also thought though did not plan to test it.
As for mains stability. They are indeed stable over time weeks and months
and are corrected. This was a use case for numbers of the austron clocks and
freq references.
Plus the frequency accuracy is needed for inter-tie networks and power
sharing/selling.
Regards

On Wed, Apr 20, 2011 at 11:17 AM, Joseph M Gwinn <gwinn at raytheon.com> wrote:

> time-nuts-bounces at febo.com wrote on 04/20/2011 10:38:41 AM:
>
> > From:
> >
> > cook michael <michael.cook at sfr.fr>
> >
> > To:
> >
> > time-nuts at febo.com
> >
> > Date:
> >
> > 04/20/2011 10:39 AM
> >
> > Subject:
> >
> > Re: [time-nuts] 60hz disciplined watch
> >
> > Sent by:
> >
> > time-nuts-bounces at febo.com
> >
> >
> >
> >
> > Le 20/04/2011 16:17, John Ackermann N8UR a écrit :
> > >
> > > I wonder if it's smart enough to have a sanity check to determine
> > > whether the line frequency is 50 vs. 60 Hz?
> > >
> > > BTW -- I have an Ecodrive watch, but it's radio controlled (as well as
>
> > > solar charging), so haven't seen any reference to this setting method
> > > before.
> > >
> > > John
> > > ----
> > >
> > > On 4/20/2011 10:13 AM, paul swed wrote:
> > >> My bet would be flicker and divide by 120. Doesn't really matter. But
>
> > >> since
> > >> these watches use the light to charge the battery, sensing the
> > >> frequency is
> > >> a byproduct. Nice and simple.
> > >>
> > I don't buy it. Makes a nice urban myth though. Incandescent sources
> > don't flicker like fluorescent sources and the Skyhawk user manual does
> > not recommend charging in front of flouresecent tubes to
> > maintain accuracy.
>
> There is plenty of 120 Hz (or 100 Hz) ripple on incandescent light.  No
> fluorescent lamps required.  It's easy to test the issue with a photodiode
> and a scope.
>
> Joe
>
> _______________________________________________
> 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