NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Frank Reed
Date: 2018 Aug 8, 16:57 -0700
And every smartphone is also a time signal receiver through GPS (the majority of smartphone chipsets are also Glonass receivers and new, high-end smartphones are already shipping with Galileo and Beidou capability, too). They are receivers for "radio time signals" directly drawn from atomic clocks, and they're a hell of a lot more sophisticated than the old "beep beep beep" signals we're used to. Every smartphone is an atomic clock "repeater". The atomic clocks are in orbit.
We can get a little nostalgic about the "Decline of the Beeps" (book title? ...or horror movie title?), but the distribution of time by broadcast is far more universal today than ever before and much more accurate, even though that accuracy is sometime a bit diminished in visible practical displays.
By the way, there's another time synchronization system that is disappearing as we speak, though one that is nearly forgotten: electric utility synchronization. Within the past year both in the US and in Europe, the modest impracticality of maintaining clocks synchronized by mains electrical power has led to changes in operating procedures, effective in the near future. For decades, especially from the 1930s through the 1960s, if you had a relatively cheap clock plugged into a wall outlet, it might gain or lose a few seconds during the day as system load changed, but the utilities were regulated to maintain the total number of daily electrical cycles so that those clocks maintained near perfect synchronization across a large geographic area. A vintage "plug in" clock would even maintain time this way last year. No more... Like the time ticks on regular broadcast radio stations, technology has moved on. GPS wins again.
Frank Reed