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Clocks, time and WWV



Danny (and group),

Thanks for sharing the link with us.  I downloaded and tried the
program.  It is very similar to the one I'm using, and posted to this
reflector.

I have made some observation, which I'd like to share with you and the
group.

Time is an exact element.  Einstein also told us time is relative. 
Using several "tools" available to me, I have made a very unscientific
analysis of our methods for updating our timepieces.

Using WWV broadcasts, as received on my HF transceiver, for a reference,
I attempted to analyze exactly how close each method is, in relation to
that standard.  Understand also, that any analysis here is subject to
the inaccuracies of the reaction time between my eyes, ears, brain and
fingers.  For all intents and purposes, and of these methods would be
adequate for updating your computer to track satellites.

I present the methods, in order of accuracy, as perceived from my
position.

GTE digital telephone:
I carry a cellular telephone with me.  It is a land based cellular
phone, which my friend Matt tells me is part of a hybridized system that
uses a constellation of satellites to set and keep time.  Although my
phone does not display the time in seconds, the minute "clicks" over at
the same instant I hear the top of the minute tone on WWV.  After
several sessions of analysis, I have determined this is my most accurate
timepiece.

Internet Time Update Program(s):
Date/Time, downloadable from http://www.primasoft.com/index1.htm AND the
link you sent us, NISTIME, available from
http://www.bldrdoc.gov/timefreq/javaclck.htm AND the Java Console
viewable from the same site all keep about the same time relationships. 
The BEST I could "make" it do was lead WWV by approximately 100 ms. 
This particular method varied wildly, depending on time of day, and the
load on the Internet.  More packets mean slower response times.  The
results varied from trailing WWV by over a second, to leading it by 300
ms.  Not the most accurate, but still very usable for our needs.

GPS:
I picked up a Garmin II from one of the FL hamfests last year.  It is a
very handy device and one of the neatest electronic toys I've ever had. 
Unfortunately, for timekeeping purposes, it was less accurate than my
Mickey Mouse watch.  Mine lags WWV by around 300 ms.  Other users have
told me it varies and they have seen it as much as 5 seconds off.  I can
neither confirm or deny these claims, as during the window of my
experiment, mine was consistently 300 ms off.  Maybe this is the time
delay from the satellite orbit to my device.

Which device will I use?  I will probably continue to use the Internet
update program Date/Time, because it is easy.  I will however ONLY
update the clock during early morning hours when the Internet load is
down.  And of course, I will check it against my Mickey Mouse watch from
time-to-time to make sure it is still accurate.

73, and thanks for offering your piece to the dialogue!  Mike

Dan Huton wrote:
> 
> Hi Mike (KF4FDJ) and All.
> re: WWVB clock time.
> NIST - National Institute of Standards and Technology have a freebie
> program called NISTIME to sync your pc with the atomic clock.
> They also have a dial-up version for those without internet access.
> The url is: http://www.bldrdoc.gov/timefreq/javaclck.htm
> You get there via: http://www.nist.gov/
> It allows you to select the various Gov. servers.
> Check it out.
> Its amazing how much the PC clock drifts!
> Regards,
> Danny
> VA3JDH
> 
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