Atomic clocks are controlled by a radio signal produced by the National Institute of Standards and Technology in Fort Collins, Colorado. The receiver inside the clock automatically adjusts the time. Resetting is accomplished when a new signal is received.
Reposition the clock
If your clock doesn't reset automatically, it could be because it cannot receive the radio signal. Relocating the clock on a different wall or adjusting the position so that it's closer to a window may improve signal reception. When the signal is received, the clock automatically resets.
Remove the clock from interference
Computer monitors can cause interference to the radio signal. Place the clock farther away from the monitor, allowing the radio signal to be received and resetting the clock. Some types of building materials can also block radio signals. Metal buildings and homes sheathed in steel siding may not be appropriate locations for atomic clocks.
Remove the batteries
Remove the batteries or unplug the clock to disconnect it from the radio signal. Power it up again, and give it a few minutes to search for the signal. Once the signal is located, the clock resets to the correct time. This procedure is best done at night when the signal is stronger.