Modern watches too, e.g. Casio digital watches marketed as integrating their "Wave Ceptor"/"Multi-Band 6" feature[1].
I still use a 17-year-old (batch code[2] 202A327G) G-Shock GW-530A (predecessor of this active offering[3]) that syncs with WWVB every morning several hours before dawn.
[1] https://en.wikipedia.org/wiki/Casio_Wave_Ceptor
[2] https://shockbase.org/watches/batchcode.php
[3] https://www.casio.com/us/watches/gshock/product.GW-M530A-1/
Do these usually have an adjustment button for a time zone offset? And how do they handle DST – do they have an "I'm in Arizona (but not in the Navajo Nation), leave me on standard time" switch?
As I understand it, the US switches at the same day across the country (for the states that do have it), so that should theoretically be possible.
So instead of a switch to “add an hour”, there could be one that says “add an hour if the signal says DST is currently in effect”.
[1] https://en.wikipedia.org/wiki/WWVB#Amplitude-modulated_time_...
https://www.nist.gov/pml/time-and-frequency-division/time-di...
That said, my clock stopped syncing for some reason, so ...
I think there are also older industrial applications using this technology to syncronize.