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Very misleading article indeed. I have to add that GPS messages include TAI-UTC offset. That means that user of even old, non-internet-connected GPS receiver t
by nousermane 4y ago
Very misleading article indeed.
I have to add that GPS messages include TAI-UTC offset. That means that user of even old, non-internet-connected GPS receiver that didn't have any software updates in a decade, will still read out exact UTC time with cumulative leap seconds correctly applied.
- terinjokes 4y agoWell, they would, if they knew which epoch they were in, which isn't transmitted by the satellites, and on many receivers, isn't something an end user can easily change. I have many fine examples of early to mid 1990s GPS receivers which can, eventually, get the full almanac and determine the geographical coordinates, but can't correctly figure out what day it is.
- nousermane 4y agoAh, yes. The infamous 1024-week (19.5 years) GPS epoch. I take back my "two decades" claim.
- terinjokes 4y agoI think with some of my Garmin units you can connect them via serial and use an old Windows 98 application to sync the current PC time, which it will use as the basis for figuring out what week it's in. I haven't gotten the application working though.
- the_mitsuhiko 4y ago> Well, they would, if they knew which epoch they were in, which isn't transmitted by the satellites Realistically that is only a problem for devices not yet supporting the 13 bit week field or if we still use GPS in 150 years and even then heuristics could solve this problem unless devices exist that without software updates will live for longer than ~100 years.
- deleted 4y ago[deleted]
- jasonwatkinspdx 4y agoI'd forgotten that. Thanks for the correction :).