[ntp:questions] GPS-UTC Leap Corrections

Hal Murray hal-usenet at ip-64-139-1-69.sjc.megapath.net
Tue May 5 08:11:24 UTC 2009

In article <485551ee-a847-45b6-a040-624dc80ce2e2 at s38g2000prg.googlegroups.com>,
 cjc <yheffen at gmail.com> writes:
>We have some time servers with GPS clocks. One of their uses is in
>operations centers where satellites are being flown. The satellites
>GPS (as opposed to UTC) internally, so we want the computers on the
>ground also to use GPS (rather than UTC). The time servers speak NTP
>and hand out GPS time as if it were UTC. The ground computers think
>they are on UTC, but it's really GPS.
>But we'd like some of the computers to really be on UTC. I really
>been able to think of a good way to have computers use the GPS time
>given out by the time servers as a source, but then to actually offset
>their own time by the GPS-UTC difference. Some quick Googling hasn't
>turned anything up. Anyone have some suggestions on how to manage
>something like this? Or are we just going to have to live 15 seconds
>ahead of the rest of the world?

The GSS satellites also tell you the offset from GPS time to UTC.
Most of the (low cost) GPS receivers tell you UTC rather than GPS.

Things get interesting around leap seconds.  Other than that,
UTC via GPS works pretty well.

What type of GPS clock/receivers are you using?

These are my opinions, not necessarily my employer's.  I hate spam.

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