On Thu, Feb 13, 2020, 12:36 PM Tom Van Baak <t...@leapsecond.com> wrote:
> > I thought of Loran... but you need 2 stations for time, I thought... > > 2 (or more) Loran-C stations gave you more accurate time. But if you know > where you are, and since the stations don't move, you can manually adjust > for signal propagation delay to some extent. This is not unlike how one > obtains time from WWV or WWVB. > One of the big issues with LORAN C, I thought, was that those variations were measured in microseconds... But I guess those average out over time so if you have a stable local oscillator you can recover time fairly well. Fun fact, LORAN has no leap seconds (since it is just a bunch of different rates). So to calculate time of coincidences with UTC you had to basically use TAI - 10s since the LORAN signal is paced with SI seconds. When I was working on the replacement timing system for the LORAN chains, this was a big deal since to start LORAN you needed to know both the UTC time and a recent / near future table of leap seconds... This leads to a lot of edge cases, especially when you needed to cope with the cold spare GPS reciever case. :(. It's also where all the love I feel for leap seconds left my body... Warner > /tvb > _______________________________________________ > LEAPSECS mailing list > LEAPSECS@leapsecond.com > https://pairlist6.pair.net/mailman/listinfo/leapsecs >
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