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A comment on Time.is. Parent comment

Re:Time.is by apaprocki on Sunday March 11, 2012 @03:34PM (#3691045)
In order to achieve the highest possible accuracy, you have to bring in your own hardware. We use appliances with internal rubidium oscillator clocks which also synchronize with the signal from all visible GPS satellites. This is as good as one can get if you really want to ensure proper time without having an external dependence on a third party or network.

edit: A paper from 1989 on the subject: http://tycho.usno.navy.mil/ptti/1989/Vol%2021_14.pdf

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Re:Time.is by dfc on Sunday March 11, 2012 @04:00PM (#3691121)
But you are relying on a third party / network. Your rubidium clock is only good for accurately measuring the length of a second. It has no idea when a UTC second begins. You are relying on GPS time in order to know when the UTC begins.

You need time and frequency for "proper time."

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Re:Time.is by tlb on Sunday March 11, 2012 @04:11PM (#3691149)
You can measure the angle of the sun to sync with UTC. I believe you can get within seconds using commodity equipment.
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Re:Time.is by dfc on Sunday March 11, 2012 @04:20PM (#3691177)
Without relying on a third party for an accurate GPS fix on your location?
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