Sunday, August 15, 2004

"Atomic Clock" on Sale. I usually work at the office on Saturday mornings. Its quiet, no one else is usually there, the telephone doesn't ring. I can sit and actually think. At the end of the morning, I reward myself with a trip to the RadioShack store on Flagler Street, across from Burdines. So I walked in yesterday.

When I go to a RadioShack, I usually go to the back half of the store, beyond the TV sets and stereos, to where the good stuff resides. I look for the little yellow price tags that they hang on things that the store is clearing out. One of those was hanging from an "Atomic Clock". It was marked down to $14.95 from somewhere above $25. I bought it. This is an amazing clock, and you should rush to RadioShack and get one.

An "Atomic Clock" looks like a regular wall clock. It does not explode, so there is nothing to fear. Instead, it keeps time by means of a built-in, tiny radio receiver linked to a micro-processor. The radio receiver picks up long-wave radio signals broadcast from WWVB a government radio station in Ft. Collins, CO. The Ft. Collins radio station is linked to the US National Institute of Standards and Technology, Time and Frequency Division in Boulder. At the institute, a "team of atomic physicists continually measures every second of every day to an accuracy of ten billions of a second per day. These physicists have created an international standard, measuring a second as 9,192,631,770 vibrations of a cesium 133 atom in a vacuum". The "atomic clock" is the device that does this measurement, not the thing now hanging from a wall in my house.

WWVB that broadcasts the time from the "atomic clock" several times a day on a long-wave frequency that can reach every part of the continental US. The receiver in my clock picks up the signal, and the microprocessor to which it is connected works the second, minute and hour hands to reset the clock. This happens usually at night, which is the most successful time of day for propagation. It happens automatically. All one has to do is put in a single AA battery (not supplied, of course) and hang the thing up.

Not only are cheap wall clocks made with this technology, there are wrist watches, nicer clocks, and other time keeping devices. A few months ago, we bought a new clock-radio-cd player for the kitchen. When we turned it on, it automatically set the clock because it had the same sort of radio receiver/microprocessor that my new all clock has.

No comments: