What is a Radio-Controlled(RC) Clock?

With a Radio-Controlled Clock, you have the most accurate timepiece within the continent. It can receive the time signal transmitted by the National Institute of Standards and Technology (NIST), which is regulated by 3 atomic clocks and deviates less than 1-second within 3000 years. The NIST broadcasts the time signal continuously and this signal can be received anywhere in the continental USA that long wave (AM) radio reception is possible. Therefore any of these clocks will receive the signal within broadcast range anywhere an AM signal can be received. Generally the signal cannot be picked up in massive metal and concrete structures unless near a window. In addition, some environmental effects may affect the transmitting distance. For more information, please study the web page of NIST at: http://www.boulder.nist.gov/timefreq