Time Marches On....

I have always been fascinated by time and clocks.  I have owned every kind of wristwatch from Timex watches that use a balance spring to a Seiko that uses a quartz crystal to a Casio that uses an “atomic clock.”  

 

It was fun asking another engineer at work what time it was and then comparing his watch to mine.  It would invariably start an argument as to which watch was the most accurate.  I would smile and say, “Well, my watch is synchronized every day against the atomic clock at the National Institute of Standards and Technology (NIST) in Fort Collins, CO.  It is accurate to within 1 second per 138 million years.^”  That usually ended the argument.  Only engineers would argue about the accuracy of a watch. 

The NIST operates a radio station, WWVB, which has for half a century been the nation’s official time keeper.  While millions of Americans are fast asleep, clocks and wristwatches across the country wake up and lock on to a radio signal beamed from the base of the Rocky Mountains.  The 60 kHz signal contains a message that keeps the devices on time, helping to make sure their owners keep to their schedules and aren’t late for work the next day.  In 2011, NIST estimated the number of clocks and wristwatches equipped with a WWVB receiver at over 50 million. 

Some manufacturers refer to their radio controlled clocks as "atomic clocks", which isn't really true. An atomic clock has an atomic oscillator inside (such as a cesium or rubidium oscillator). A radio controlled clock has a radio inside, which receives a signal that comes from a place where an atomic clock is located.  At 60 kHz, there isn't enough room on the signal (bandwidth) to carry a voice or any type of audio information.  Instead, all that is sent is a code, which consists of a series of binary digits, or bits, which have only two possible values (0 or 1).  They are sent at a very slow rate of 1 bit per second, and it takes a full minute to send a complete time code, or a message that tells the clock the current date and time.

Once your radio controlled clock has decoded the signal from WWVB, it will synchronize its own clock to the message received by radio. Before it does so, it applies a time zone correction, based on the time zone setting that you supplied. The time broadcast by WWVB is Coordinated Universal Time (UTC), or the time kept at the Prime Meridian that passes through Greenwich, England.   UTC is the primary time standard by which the world regulates clocks and time.

 

Engineer David Andrews (left) and technician Robert Oase (right) are shown by the WWVB transmitter in 1963. Credit: NIST

 

Keep in mind, though, that the accuracy of the watch will also depend on the update frequency, because between updates the watch’s internal clock is running freely, and the overall accuracy is determined by the drift the internal clock experiences. 

Well, enough of the technical stuff because today that has all changed.   It is time for me to get a new wristwatch.  It is called a “smart watch.”  This watch uses a satellite-based Global Positioning System (GPS) which uses two onboard cesium atomic clocks and as many as two rubidium atomic clocks as backup to accurately determine the location, height and current time.  Smart watches have built-in GPS receivers to periodically set the correct time from various satellites.  This means that GPS can achieve an accuracy level of 50 ns deviation from the UTC.   A nanosecond is 1/1,000,000,000 of a second.   

My wife just ordered me the Samsung Galaxy Gear S Smart Watch for Christmas.  My old Casio watch disappeared when my 2-year-old grandson found out he could reach the lid of our trash can and throw things away.   Keys, cell phones and other items have gone missing from our house.  I am not about to let him play with the new watch.

 The Samsung Galaxy Gear S Smart Watch

                         

The first 4G wireless network-connected watch with a 2-inch curved AMOLED display and interchangeable watch faces allows you to not only tell time, but check emails, answer calls, view GPS maps and retrieve turn-by-turn directions.  It also will track your fitness goals and monitor your heartbeat.   You can also reply to texts with a virtual keyboard along with word prediction and voice command.     It has Bluetooth so I can sync with my car and talk hands-free while driving.  I know to keep both hands on the wheel.

 

 

 

 

 

 

 

 

 

 

I am old enough to remember Dick Tracy and his wristwatch.  I dreamed of being able to talk over the phone by just holding up my wrist.  That was a real miracle at a time when phones were not wireless.  I know this Christmas present is a “toy” but I am always leaving my phone at home or not charging it.  Now I can use the smart watch along with my Samsung Galaxy S5 and I don’t have to be in the same room. 

What a joy it has been to see how far technology has come.  We can argue it wastes time or interrupts our life, but the sheer accomplishment is worth talking about.  Can I live without it…..Sure.  But why not enjoy what technology has to offer.     

Time Marches On!