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A comment on I tried to adjust the time on my alarm clock. Parent comment

Re:I tried to adjust the time on my alarm clock by shaftway on Monday November 04, 2019 @04:12PM (#21446558)
If only we had some kind of National Institute of Standards and Technology that broadcast the time and daylight savings flags in a machine readable format.
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Re:I tried to adjust the time on my alarm clock by scintill76 on Monday November 04, 2019 @04:21PM (#21446633)
If only it were possible to receive such a broadcast without needing wifi.
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Re:I tried to adjust the time on my alarm clock by scrooched_moose on Monday November 04, 2019 @05:23PM (#21447240)
It is:

https://en.wikipedia.org/wiki/Radio_clock

https://en.wikipedia.org/wiki/WWVB

I've had several that set automatically after plugging in, without the need for wifi.

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Re:I tried to adjust the time on my alarm clock by p1mrx on Monday November 04, 2019 @06:58PM (#21448137)
It is possible to find real WWVB clocks, but note that most of the cheap "auto set" ones just have a lithium battery to remember whatever time was set at the factory.

It'd be cool if WiFi routers could broadcast the time unencrypted, for use by passive receivers, but that would get annoying if one near you is set wrong. Perhaps there could be a trusted source of signed timestamps, and a receiver just takes the maximum.

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Re:I tried to adjust the time on my alarm clock by Gibbon1 on Monday November 04, 2019 @07:34PM (#21448402)
Better is just use GPS. You can passively listen without being tracked and you get the time and location. GPS is getting cheap enough ($10/1000 qty) to be a good option for this sort of thing.
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Re:I tried to adjust the time on my alarm clock by Spivak on Monday November 04, 2019 @10:05PM (#21449230)
Doesn’t work super well when your clock needs an unobstructed view of the sky. How many clocks in your house have that?
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Re:I tried to adjust the time on my alarm clock by shaftway on Tuesday November 05, 2019 @02:08AM (#21450331)
It's not like it needs a solid fix though. It just needs a single satellite signal to get through, which is way more reasonable.
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Re:I tried to adjust the time on my alarm clock by Gibbon1 on Tuesday November 05, 2019 @02:22AM (#21450378)
I have a higher end GPS module. Building I'm in is corrugated steel sided with a metal roof. After being on for an hour the coordinates show... my desk. Far as I can tell.

GPS transmit power is 44db with a 13 db antenna gain. I think. And -140 db sensitivity (typical) So close to 200db of link margin. And the transmitter isn't in clutter either.

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Re:I tried to adjust the time on my alarm clock by codedokode on Monday November 04, 2019 @07:18PM (#21448276)
Don't mobile networks broadcast the time already?
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Re:I tried to adjust the time on my alarm clock by scintill76 on Monday November 04, 2019 @08:15PM (#21448660)
Yeah, I was continuing the GP's sarcastic comment about WWVB etc.
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Re:I tried to adjust the time on my alarm clock by kempbellt on Monday November 04, 2019 @04:23PM (#21446655)
GPS clocks do just this - https://timetoolsltd.com/gps/what-is-the-gps-clock/
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Re:I tried to adjust the time on my alarm clock by jodrellblank on Monday November 04, 2019 @04:44PM (#21446841)
So do non-GPS plain old longwave and shortwave radio clocks - https://en.wikipedia.org/wiki/Radio_clock
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Re:I tried to adjust the time on my alarm clock by felipelemos on Monday November 04, 2019 @04:43PM (#21446833)
GPS clocks works inside a bedroom without a clear view of the sky?
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Re:I tried to adjust the time on my alarm clock by icebraining on Monday November 04, 2019 @06:45PM (#21448036)
My GPS receiver works just fine inside, even with the window blinders closed. I suppose it might not in a windowless room.
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Re:I tried to adjust the time on my alarm clock by treve on Monday November 04, 2019 @05:58PM (#21447584)
GPS clocks respect local timezone and DST rules?
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Re:I tried to adjust the time on my alarm clock by dreamcompiler on Monday November 04, 2019 @04:39PM (#21446799)
I have several in my house. NTP amd WWVB are two different things.
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