Oz-in-DFW writes: > > ... There is no way AT&T would be 12.4 seconds off ... > > > > I used to work in the cell infra business. While it's less true today, > there are still a number of operators that do not sync system clocks. > The time supplied to users can be **minutes** off. > > Most newer operational standards can't tolerate this and "accurate" time > (better than a ms) is important. WiMAX requires TDD base stations to > base station alignment to be better than 1 microsecond. Most telecom > operators want to avoid GPS at every site. It's a logistical PITA.
Here in the Bay Area, AT&T/iPhone time has gotten noticeably worse recently. The error used to be around 4 seconds; now it's 49 seconds (!). Emerald Time is fine for interactive use, but what I find very impolite is that AT&T's bad timestamps are written into the EXIF headers on photos. Sometimes I take pictures of sundials, for example, and a 49-second error is not negligible for a carefully made dial. It would be amusing to arrange for a long-term record of the offset of one's phone (which can of course change across multiple providers during travel), say by using a background process to take a sample every few hours against NTP sources or against GPS if the phone has it (or both). Then any photos can be batch-corrected later if desired. Apple, give me control over the time on my own phone, and please don't force me to resort to these schemes :-). Cheers, Peter Monta _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
