Actually “Radio Controlled Clocks”
An Atomic clock is a general name that describes various time-keeping devices based on the regular vibrations associated with atoms. Many clocks you may purchase today offer an “Atomic Movement.” These are actually “Radio-controlled” clocks that receive the correct time from the Fort Collins, Colorado National Bureau of Standards Cesium (atomic) clock.
How a Radio Controlled Clock Works:
Radio-controlled clocks set themselves by listening to the radio signals of the NIST Atomic Clock in Fort Collins, Colorado. Radio-controlled clocks receive a 60-kilohertz, low-frequency AM radio signal from the WWVB radio station maintained by the National Institute of Standards and Technology (NIST). The NIST is the official timekeeper for the US and is located in Boulder, Colorado. Its WWVB station is located nearby in Ft. Collins. The NIST and its sister agency, the US Naval Observatory, participate with an international coalition of agencies to determine official world time, called Coordinated Universal Time (UTC).
As soon as the Radio Controlled Clock caches the signal, the hands will spin at 20 times their normal rate, and the time is adjusted to accuracy with less than a one-second deviation in one million years! When you place the battery in the radio-controlled clock, do not expect it to snap to the correct time, as it will not. The radio-controlled clock must first be told where you are by selecting the time zone for where you are in the US. The movements available for analog clocks (clocks with hands) are programmable for EST, CST, MST, and PST. These will not work in Alaska or Hawaii.
If the clock does not receive the low-frequency AM radio signal from the WWVB radio station in Colorado, your clock will not function correctly. If you are close to Colorado, you should not have a problem, but in downtown Manhattan you may have an obstacle because of the distance, the obstructions (tall buildings) and stray RF signals (Radio Frequency) emitting from other AM sources and computers. Many times in remote areas if you set the clock and leave it near a Westerly facing window, it will pick up the signal and set itself. This will work better at night when the AM signals travel farther or when it may be cloudy where the signal may bounce. Hang your clock after it picks up the signal. Even in remote areas with obstructions, the clock will probably occasionally pick up a stray signal and correct itself.
If your analog radio-controlled clock (clock with hands) doesn’t pick up the signal within a day, try the following:
1) Take out the battery and place it backward for about 10 seconds, then replace it in the correct position.
2) After replacing the battery, press the Time Zone button on the back for about 5 seconds, corresponding with the time zone where you are located.
3) Shortly after, the hands should start turning 20 times their normal speed and stop at 4:00 or 8:00 or 12:00. This means the clock is working properly and now looking and waiting for the signal.
4) Place the clock near a westerly window overnight, and then the clock should reset overnight and read the correct time.
**If you had previously pushed the manual mode flap (switch), take a pen or paperclip and make sure it is pulled out in the off position.
