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Subject: Re: Online WWV time?
From: brian whatcott (inet@XXX.XXX)
Date: Wed Oct 24 2001 - 18:25:38 EDT
At 10:49 10/24/01 -0700, you wrote:
>I am looking for an online broadcast of WWV time? Anybody knows if there is
>one? (And what its offset with the true broadcast would be.) Alternatively,
>what are reliable sources of time broadcast on the Web?
>
>YA
>
>PS: A subsidiary question is: has anybody used NTP (the Network Time
>Protocol) with success to get a good clock for navigation on a laptop, for
>example? It should work well I believe.
I realise that proposing GPS as an aid to traditional navigation methods
is paradoxical, but it is possibly the most accurate time source you have
on hand.
A radio to capture the time standards at 2.5MHz 5MHz,7.5MHz, 10MHz etc.,
builds in a modest transmission time variability, depending on distance &
signal path of about 200 miles per millisecond.
An internet transmitted clock standard (Like 'Atomic Clock' - a NASA utility
which connects to the primary or secondary standard of your choice) adds
another
variability: the utility will account for the average transmission latency,
but variation from rerouting means that the 100 to 400 milliseconds of delay
that you might see accounted for is still variable.
I am tempted to rig a box with a velvet covered aluminum block, in which
three chain store five year battery analog watches could be kept.
Temperature stabilization is so helpful that a watch on your wrist
maintained at a fair 98 degrees Fahrenheit can give a chronometer a run
for its money.
At least 2 of the 3 have a fair chance of surviving for a year or two....
brian whatcott <inet@XXX.XXX> Altus OK
Eureka!
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