How to Set a Radio Controlled Atomic Clock

By Patrick Nelson

Radio-controlled clocks are clocks with radios in them. The radio picks up time signals from the National Institute of Standards and Technology (NIST) radio station in Boulder, Colorado. The radio station is linked to an atomic clock, which is the most accurate timekeeping device in the world with a time deviation of less than one second in one million years. The station, called WWVB, continually broadcasts the time at 60kHz. The time code contains the year, day of year, hour, minute, second, and flags that indicate the status of Daylight Saving Time, leap years, and leap seconds.

Step 1

Remove the battery cover and insert fresh batteries. Make sure you get the polarity correct and that the plus and minus labels match up.

Step 2

Close the battery cover, and the display will flash or indicate in some way that it is powered. If it doesn't, find the reset button. It will be marked as such and will either be a button or a pinhole. Hold the button down for a few seconds.

Step 3

Take a look at the display, and you will see the clock starting to scan for a signal. The display will read 2:00 a.m. when you start the clock---it's the default time. If the clock can receive a signal, it will change the display to the received time within 10 minutes.

Step 4

Wait 10 minutes and check to see if the display is showing the adjusted time. If it does, your clock is set and you don't need to perform any additional steps.

Step 5

Wait another two minutes if the clock hasn't received a signal, and the clock will switch off.

Step 6

Relocate the clock to near a window and away from any electronic equipment that might cause interference. Make sure the clock isn't sitting on any metal surfaces.

Step 7

Press the Receive button and allow the clock to try to pick up a signal again. It will try again automatically after an hour. Try it overnight and just leave it---the reception might be better during later hours.

Tips & Warnings

  • The clocks usually have a signal strength meter. The more bars on the icon, the better.