Hi The original location of the PPS was from astronomical data. That's still what ultimately steers UTC.
More precisely, for the US, there's a telescope at the Naval Observatory that watches the sun as it comes overhead. The point it hits this or that mark on the telescope tells you what the official solar time is (after some math). The current one has been in place since the late 1800's, and it's still in use. Bob -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Bob Bownes Sent: Friday, January 20, 2012 12:23 PM To: Discussion of precise time and frequency measurement Subject: [time-nuts] Determination of the placement of the first pps As I am, as Heinlein would say, but an egg in terms of time-nuttery, perhaps someone could point me toward some history in order to help answer a question recently posed to me. At what point was the original global 1pps leading (trailing?) edge defined/distributed and to what was (is) it referenced? Someone, someplace, had to give the original time 'hack', no? I found I could talk about all the wonderfullness of GPSDOs, rubidiums, ocxo's and the like but couldn't answer that simple question with much more depth than 'NIST does it for the US' or 'you pull it off of the GPS'. Thanks, Bob _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
