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Re: Timekeeping and sight time records
From: Richard B. Langley
Date: 2005 Mar 17, 08:35 -0400
From: Richard B. Langley
Date: 2005 Mar 17, 08:35 -0400
You are thinking about the difference between GPS (System) Time (which is not
updated for leap seconds) and UTC which is compensated for leap seconds to
keep it within 0.9 seconds of UT1. Currently the difference is 13 seconds.
Nothing to do with "satellite rollover."
-- Richard Langley
On Wed, 16 Mar 2005, Bill wrote:
>> Yes, it is perverse to use the GPS as a time source, but having access to a
>> $50 million dollar time source for less than a hundred bucks, that's
>> something to seize and not let go of.
>
>Not clear about my recollection, the source of it, or current standards; but
>in the early days of GPS I somehow recall it could be up to 12 seconds off
>before a satellite rollover.
>
>Did I misread, recollections fail, or was/is there some truth to this?
>
>Bill
>
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Richard B. Langley E-mail: lang@unb.ca
Geodetic Research Laboratory Web: http://www.unb.ca/GGE/
Dept. of Geodesy and Geomatics Engineering Phone: +1 506 453-5142
University of New Brunswick Fax: +1 506 453-4943
Fredericton, N.B., Canada E3B 5A3
Fredericton? Where's that? See: http://www.city.fredericton.nb.ca/
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