An atomic digital watch is a wristwatch that is radio controlled to keep the most accurate time on the planet. This means the owner of the wristwatch never actually has to set the time on the watch, it is done automatically. How cool is that!
So how is this possible, I hear you ask? Well without getting into gory technical detail, an atomic digital watch receives a low-frequency radio signal from a number of transmitters. Of course this depends on your location around world. If you live in the US, your digital watch can achieve perfect synchronization with the US (WWVB Atomic Clock) located near Ft. Collins in Colorado (WWVB). This station was set up and is operated by NIST – the National Institute of Standards and Technology. High five to those guys. This has a transmission radius of about 3000km, making it available across most of the US (North America). With exception, as far a I know, to Alaska and Hawaii. Don’t quote me on that.
Naively assumed, it may also be interesting to note that this transmitter does not only function to update the digital watch on your wrist. It also provides the ability to synchronize the time on computers and other electrical equipment. In the background, again without boring you with the technical detail, another form of timepiece known as a Cesium clock is used. Okay, here is another one to remember when bragging to your friends in the bar. These Cesium Atomic Clocks have an accuracy of one second in 60 million years! That is to say in layman’s terms, that the clock may lose/ gain a second every 60 million years (Cesium Fountain Atomic Clock). Scientists are currently working on technology to increase this accuracy to 1 second in 10 billion years ( http://www.ntp-time-server.com). When researching this, I had to ask myself the question, does it really matter? Like, it is very unlikely that the human race will be around in a million years. However, I do concede that some technical equipment may require this accuracy. Humorously, I can picture a load of geeks standing around looking at a giant Casio thinking, How the hell can I make this more accurate!
There is another atomic clock that provides synchronization for atomic digital watches in Europe. Accurate time is available across Europe using the MSF and DCF Atomic Clock time signals transmitted from Rugby and Frankfurt, they provide the ability to synchronize the time on computers and other electrical equipment in Europe.
The European and US atomic clocks both transmit different frequencies. So, if you purchased your digital atomic watch in the US and you happen to travel outside of the Colorado transmitter radius, the wrist watch will function like a normal quartz watch. Well I suppose this would be expected. I would be straight back to the store with mine if it didn’t!
This all means that your timepiece will never run slow or fast. So there is no excuse being late for work the next morning. But not only this, your watch is military synchronized. If your a tech head in anyway, you can brag about the accuracy of your digital watch at the bar, however cool or uncool that may sound! So one of the general hype factors about these category of digital watch is that they are ridiculously accurate.
Most Atomic watches have a feature that allows you to see when it was last synchronized. You can also manually tell it to search for the radio signal; otherwise the watch is programmed to look for the signal in the middle of the night when radio interference is at a minimum. How nice is that?