Sorry if this is a dumb question, but do you guys not have radio controlled clocks outside of Europe? If I got it right, the only purpose of this project is to always display the correct time. Radio controlled clocks do exactly that. They are cheaper than the one ESP board, and run years on a single AA battery. No WiFi, tinkering, setup, or cables necessary
If you think this is overengineered, I built one that will really offend you: https://github.com/jcalvinowens/wallclock :)
The point is to have fun and learn something, not really to solve a problem in a practical sense. The radio controlled clocks are extremely unreliable where I live.
There are time signal stations all over the world, WWV is the most prominent US one https://en.wikipedia.org/wiki/WWV_(radio_station)
https://en.wikipedia.org/wiki/Radio_clock#List_of_radio_time...
There is (https://www.nist.gov/pml/time-and-frequency-division/time-se...) and in some conditions you can receive the time signal in the UK.
Our office manager bought some US tuned radio wall clocks, and every now and then they would jump 8 hours forward. I assume it was down to solar weather making propagation changes (https://en.wikipedia.org/wiki/Sporadic_E_propagation)
We do, but I've never had a WWVB clock work for me in North Carolina. I've tried a few of them. The US is a big place and for whatever reason, there aren't that many clock signal transmission towers (AFAIK, the only one in the US is in Colorado).
I'm in WV, but could only get my clock to set itself when put on the correct SW-facing wall.
Obviously it defeats the purpose a bit if I need to move my clock to a different wall and wait 12-24 hours for it to set itself.
Googled "radio controlled clock" and seeing results from $20-$200, lots of inconsistency in what the product is.
These are usually marketed as "atomic time" or "atomic clock" here in the US.