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Animatsyesterday at 9:55 PM1 replyview on HN

Right. WWVB clocks running off the 60KHz pretty much solve the clock problem in the US. All my clocks at home are basic LaCrosse analog clocks. They have the internal sensors needed to tell when each hand is straight up, so they can set themselves without user input. On power up, they step until the hands are straight up, then sync when they get an update. You have to set the time zone with a switch when installing. Only the four US time zones are available. Battery life is 1-2 years, which is pretty good for a device with a radio.

There are UK and Japan clocks that work similarly, but use national time sources. There are G-Shock watches which synchronize from multiple sources. While running on solar power. Those keep accurate time with no maintenance. That's an impressive achievement.


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js2yesterday at 10:13 PM

> WWVB clocks running off the 60KHz pretty much solve the clock problem in the US.

YMMV depending upon location. I've never gotten a WWVB clock to work in North Carolina. On the East Coast, the signal maybe sorta works for a few hours overnight:

https://tf.nist.gov/tf-cgi/wwvbmonitor_e.cgi

T̶h̶e̶y̶ ̶a̶l̶s̶o̶ ̶d̶o̶n̶'̶t̶ ̶t̶r̶a̶n̶s̶i̶t̶i̶o̶n̶ ̶D̶S̶T̶ ̶a̶u̶t̶o̶m̶a̶t̶i̶c̶a̶l̶l̶y̶,̶ ̶s̶o̶ ̶y̶o̶u̶'̶r̶e̶ ̶p̶u̶l̶l̶i̶n̶g̶ ̶t̶h̶e̶m̶ ̶o̶f̶f̶ ̶t̶h̶e̶ ̶w̶a̶l̶l̶ ̶t̶w̶i̶c̶e̶ ̶a̶ ̶y̶e̶a̶r̶ ̶u̶n̶l̶e̶s̶s̶ ̶y̶o̶u̶'̶r̶e̶ ̶i̶n̶ ̶o̶n̶e̶ ̶o̶f̶ ̶t̶h̶e̶ ̶r̶a̶r̶e̶ ̶U̶S̶ ̶l̶o̶c̶a̶t̶i̶o̶n̶s̶ ̶t̶h̶a̶t̶ ̶d̶o̶n̶'̶t̶ ̶a̶d̶h̶e̶r̶e̶ ̶t̶o̶ ̶t̶h̶e̶ ̶D̶S̶T̶ ̶s̶i̶l̶l̶i̶n̶e̶s̶s̶. Edit: My bad, they can switch in/out of DST automatically, at least when they can work at all.

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