NavList:

   

Reply

Bill,
Thanks for the reference.
I conclude from your message and other messages that one cannot rely
on a radio clock for Cel Nav.
From the very begining, the idea of controlling a clock automaticaly
by radio looked weird to me. Indeed, unless really well designed,
such clocks would be unreliable.
But WELL-designed electronic clock does not need any radio signals.

However, it seems that in the specific case of our observations
in St Joseph, MI, some doubts remain, and I don't see a way to solve
the question, what really happened: one of the two rare things hapened:
either the clock was 1min off or we observed some extraordinary
refraction.

I think that the first thing is more likely, Bill thinks otherwise.
And there is no way to decide.

Alex.

On Sat, 24 Mar 2012, Bill Noyce wrote:

>
> You can find details on how WWVB transmits the time at
> http://www.nist.gov/pml/div688/grp40/wwvb.cfm
> Summary: it sends the complete time and date every minute, but the coding 
doesn't include any form of error-correction.  Dropping one bit of data could 
certainly make a clock lock on to a time that's off by 1 minute (or 2, or 4, 
or 8, or 1 day,  etc).  But I would expect a well-designed clock to gather 
data for several minutes and check it for consistency -- there's plenty of 
redundancy if you do that!
>  -- Bill N
> ----------------------------------------------------------------
> NavList message boards and member settings: www.fer3.com/NavList
> Members may optionally receive posts by email.
> To cancel email delivery, send a message to NoMail[at]fer3.com
> ----------------------------------------------------------------
>
>
>
>
> : http://fer3.com/arc/m2.aspx?i=118491
>
>
>

   

Reply