>The atomic resonator is set to atomic time, but periodically the atomic physics unit will check to ensure that atomic time is properly locked: when this happens an oven will fix the ideal temperature, the internal laser will strike, the microwave resonator will reach oscillation and atomic time will be locked in.
There's an oven and a laser in that little watch??
Could you explain? I won't lie, most of the watches are a hassle visually. But, I can read the time from them so long as I ignore all of the extra hands and dials that are there, probably, to lend additional accuracy.
You can get refurbished rubidium oscillators from ebay for around 200$. Hooking these up to a Raspberry Pi should be fairly easy (see the pps_gpio kernel driver for that).
http://www.leapsecond.com/time-nuts.htm
A while ago I tried to measure the phase difference between two of my Rubidium ones
https://www.anfractuosity.com/projects/rubidium-clocks/
I would like to try that again at some point, if I can fix one of my clocks again, as I don't think I got the timebase setting right.
As an aside the light from the rubidium bulb, glows a really nice purpleish colour :)
I'm sure I read that there are now atomic clocks, which are so accurate, they 'tick' at different rates, depending on their height in a room.
This is what I was thinking of: http://www.riken.jp/en/research/rikenresearch/highlights/828...
It seems it's an Optical Lattice Clock.