alt Hacker News> clock sync for civilians has never been easier
I don't think civilian clock synchronization was an issue since a long time ago.
DCF77 and WWVB has been around for more than 50 years. You could use some cheap electronics and get well below millisecond accuracy. GPS has been fully operational for 30 years, but it needs more expensive device.
I suspect you could even get below 1 sec accuracy using a watch with a hacking movement and listening to radio broadcast of time beeps / pips.
Both of the WWVB clocks I've owned have been very fickle about how they're placed because RF be that way sometimes, and Colorado isn't exactly nearby to my location in Ohio.
The first manufactured GPS clock I owned (as in: switch it on and time is shown on a dedicated display) was in a 2007 Honda.
But a firmware bug ruined that clock: https://didhondafixtheclocks.com/
And even after it began displaying the right time again, it had the wrong date. It was offset by years and years, which was OK-ish, but also by several months.
Having the date offset by months caused the HVAC to behave in strange incurable ways because it expected the sun to be in positions where it was not.
But NTP? NTP has never been fickle for me, even in the intermittently-connected dialup days I experienced ~30 years ago: If I can get to the network occasionally, then I can connect to a few NTP servers and keep a local clock reasonably-accurate.
NTP has been resolutely awesome for me.