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Timely Maneuver

You'll never be late if you synchronize your computer clock to the atomic clock in Colorado.

October 19, 2000|DAVID COLKER |

Synchronize your computer's clock with the atomic clock at the National Institute of Standards and Technology in Boulder, Colo., and you'll never have an excuse for being late.

The standard to which you'll be setting your computer clock, via the Internet, is Coordinated Universal Time, or UTC.

Why UTC instead of CUT? Because in 1970, when the standard was established under an international agreement, the French protested that in their language's word order the abbreviation would be TUC. In a stroke of diplomacy, UTC was chosen as a compromise.

This synchronization can be accomplished whether you use the Windows or Macintosh operating systems. But your computer must be able to connect to the Internet.

* Windows:

1. Go to the NIST's Web page, at

2. Under "Software and Instructions," click on "Windows 95/98/2000/NT."

3. A "Save As" window will appear to allow you to choose where you want the nistime-32bit.exe software to land. After choosing a destination--I put it right on my desktop--click on the "Save" button.

4. Go to wherever you placed nistime-32bit.exe and double-click on it. A window will appear showing your computer's current time settings.

5. Pull down the window's File menu and choose "Select Server."

6. Several server choices will appear. Choose the one closest to you. The one labeled "Washington" is in Seattle.

7. Pull down the File menu and choose "Save Config" to save the server setting.

8. Pull down the Query Server menu and choose "Now." Your computer clock will reset. If it's more than half a minute off, the software will ask you to approve the change.

* Macintosh:

This method works only if you are using a version 8.5 or later of Mac OS. To check which version you have, click on your desktop to make sure you are in the basic Finder application, pull down the Apple menu at the top left of your screen and choose "About This Computer." The window that pops up will include information on your OS version.

1. Connect to the Internet. It's not necessary to start up your Web browser.

2. Pull down the Apple menu at the top left of the screen and move the pointer downward to "Control Panels." With the mouse still pressed, move the pointer to "Date and Time" and click. The control panel will open.

3. Check the box next to "Use a Network Time Server."

4. Click on the "Server Options" button. Another window will open.

5. Select among options for when your time will be updated. "Manually" will reset your clock this one time. "Automatically" will reset it now and then at regular intervals as long as you happen to be connected to the Internet.

6. Click on "Set Time Now" and your clock should sync up.


Clocking In

You'll never have an excuse for being late if you use a clock that automatically resets itself daily to the nation's official atomic clock, the world's most accurate timepiece. You can also synchronize your computer's clock. (See below)

* A 24-hour digital signal, broadcast from the National Institute of Standards and Technology, is able to reset clocks, some as small as a wristwatch, anywhere in the continental United States. The clocks available for home use sell for $30 and up and are accurate to a 30th of a second.

* The master clock, known as the F-1 Cesium Fountain Clock, in Boulder, Colo., is thought to lose no more than one second in 20 million years.

* It works by measuring the oscillating frequency of cesium atoms, the international standard since 1967.


The master clock's process has five steps:

1. A gas of cesium atoms is fed into a vacuum chamber. Six lasers slow the atoms' movement, cooling the gas to hundreds of degrees below zero Celsius and forcing them into a spherical cloud.

2. The ball of gas is tossed upward into a field of bombarding microwaves, which "prime" its electrons to emit light under certain conditions.

3. The ball falls back into the vacuum chamber to be measured.

4. When struck by a laser beam, the bombarded atoms emit fluorescent light at a frequency related to the natural resonance frequency of cesium, which is used to define the length of a second.

5. The National Institute of Standards and Technology transmits the resulting time signal by satellite, radio and telephone and over the Internet to computers and specially equipped clocks almost anywhere within the Western Hemisphere.

Sources: National Institute of Standards and Technology, Oregon Scientific

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