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Oregon Scientific has some model available for the european market, based on
a signal departing from Frankfurt, Germany. Latest model seem having very
little problem getting it, compared to previous more difficult to tune
(automatically, no manual back up, but I suppose the signal is now been
strenghtened), and the station range is declared to be up to 2500 km, so it
works here in the Med.
fair winds
Gennaro Sammarco

> -----Messaggio originale-----
> Da: Navigation Mailing List
> [mailto:NAVIGATION-L@LISTSERV.WEBKAHUNA.COM]Per conto di Dan Allen
> Inviato: giovedi 28 febbraio 2002 18.53
> A: NAVIGATION-L@LISTSERV.WEBKAHUNA.COM
> Oggetto: Re: Radio Synchronized Clock
>
>
> I found at nice stainless-steel cased wall clock at Ikea for $15
> a year or two ago (they don't have them any more, alas), and it is
> radio synchronized.  They change at midnight and have a button on
> the back for the 4 main US time zones.  They automatically change
> for Daylight Savings time.  The signal that they use is NOT WWV
> but WWVB at 60 kHz.
>
> More info on WWVB can be found at:
>
> http://www.boulder.nist.gov/timefreq/stations/wwvb.htm
>
>
> WWVB barely covers North America and it depends upon the time of day:
>
> http://www.boulder.nist.gov/timefreq/stations/wwvbcoverage.htm
>
> I think there may be other radio stations similar to WWVB.  I
> would expect that if there are similar stations broadcasting in the
> same format and frequency that my $15 clock would work
> world-wide, but with the time zones being off (not a major problem).
>
>
> -----Original Message-----
> From: Navigation Mailing List
> [mailto:NAVIGATION-L@LISTSERV.WEBKAHUNA.COM]On Behalf Of Jared Sherman
> Sent: Thursday, February 28, 2002 9:05 AM
> To: NAVIGATION-L@LISTSERV.WEBKAHUNA.COM
> Subject: Re: Radio Synchronized Clock
>
>
> Dov-
>  This (correcting a quartz count) was implemented around 1980 in
> a totally sealed diving watch which I think came out under the name
> "Pulsar" before the new company of that name. It was a
> hermetically sealed watch, solar cells for the 'face' and an LED
> display on
> the 'shoulder' of the face. Besides the time set buttons it also
> offered a calibration/adjustment mode, since there was no way to
> open the watch for internal adjustment.
>  Since then watch accuracy has improved, typically better than
> +-15 seconds a month which is well beyond what the mass market pays
> atttention to. I don't see any market incentive for a
> manufacturer to do better, unless you buy the Casio GPS watch
> which will put
> the accuracy of 16 atomic clocks on your wrist--without your need
> to manually adjust it.
>
>  I've been told the radio watches use a power conservation
> algorithm. They only turn on the receiver circuit near midnight (when the
> WWV signal should be propogating, etc. at its best) and try to
> correct themselves once every 24 hours. If they miss the correction,
> then they become more agressive about turning on and seeking it.
> This may vary with manufacturers of course...but in any case the
> watch would only need to see "sky" once daily, since the typical
> quartz accuracy of +-15 sec/month means it will still be within 1/2
> second of "right" for the rest of the day.

   

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