Chip Scale Atomic Clock (CSAC)

These can help against GPS spoofing &#x2F; jamming by identifying false signals and allowing rapid resynchronization:<p><a href="https:&#x2F;&#x2F;www.army.mil&#x2F;article&#x2F;88361&#x2F;Miniaturized_atomic_clock_to_support_Soldiers_in_absence_of_GPS&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.army.mil&#x2F;article&#x2F;88361&#x2F;Miniaturized_atomic_clock...</a><p>Also related, NASA has a spaceborne atomic clock in testing that, if it works, will make space navigation much more efficient: <a href="https:&#x2F;&#x2F;www.nasa.gov&#x2F;mission_pages&#x2F;tdm&#x2F;clock&#x2F;index.html" rel="nofollow">https:&#x2F;&#x2F;www.nasa.gov&#x2F;mission_pages&#x2F;tdm&#x2F;clock&#x2F;index.html</a>

Here it is, next to a coin, for scale:<p><a href="https:&#x2F;&#x2F;www.microchip.com&#x2F;en-us&#x2F;products&#x2F;clock-and-timing&#x2F;atomic-clocks&#x2F;_jcr_content&#x2F;root&#x2F;responsivegrid&#x2F;container&#x2F;cardgrid&#x2F;card1&#x2F;image.coreimg.png&#x2F;1606931390716&#x2F;r1-v1-200106-ftd-graph-csac-fig1.png" rel="nofollow">https:&#x2F;&#x2F;www.microchip.com&#x2F;en-us&#x2F;products&#x2F;clock-and-timing&#x2F;at...</a>

Instead of a beam of Cesium atoms being sensed with microwaves, this has a vapor cell sensed with microwave modulated light. This eliminates the finite lifespan previously associated with Cesium Beam atomic clocks.<p>Unlike Rubidium references, the light is supplied by a solid state laser, eliminating another huge power sink.<p>I expect these devices have a practically infinite life. What an amazing set of innovations.

If someone had a celestial database, and a telescope, how accurately could one determine their position on earth using this device? Assuming no GPS satellites are available.

We looked at using these in a previous job that had a very tight tolerance on RF frequency tolerance. Vibration tolerance makes the use of crystals difficult. Unfortunately, the phase noise of this device wasn&#x27;t good enough to be the frequency source for the radio itself, so we would have had to use the CSAC to discipline a tcxo. By the time we did that, it really wasn&#x27;t that advantageous. It looks like they have a low-noise option that includes a tcxo now, but (no surprise), it doesn&#x27;t appear to have a operating vibration spec.

4.95 grand a pop, move along folks

What would it be useful for, apart from all the practical purposes? i.e. putting one in a centrifuge and one next to it?

If there are any current (or ex-) Symmetricom employees reading this, then I&#x27;d love to hear about your work. I have a profound interest in the domain of high-precision timekeeping.

They put a tiny Cs vapor cell in there? That&#x27;s pretty neat.

Not quite the size to fit into a wristwatch yet.

If atomic clocks coyote be miniaturized&#x2F;commoditized that has some pretty big implications in solving distributed transaction problems.