Atomic Time
I took an hour today to drive out north of town to track down a little-known but very important facility critical to timekeeping in the USA.
WWVB is a time signal radio station near Fort Collins, Colorado and is operated by the National Institute of Standards and Technology (NIST). The station relies on extremely precise atomic clocks for the accuracy of the time signals. It sends out signals that allow millions of clocks and watches to be set either manually or automatically.
WWVB continuously broadcasts digital time codes, using very long electromagnetic waves at a frequency of 60 kilohertz, which are automatically received by timekeeping devices in North America, keeping them accurate to a fraction of a second. In 2011, NIST estimated the number of radio clocks and wristwatches equipped with a WWVB receiver at over 50 million.
Some argue the terrestrial time signal have been rendered obsolete by the government’s Global Positioning System, whose satellites also transmit time signals, but users disagree, noting GPS devices must have an unobstructed view of a number of satellites in space to properly function. Sixty kilohertz permeates in a way GPS can’t. WWVB’s very low frequency signal can be received inside buildings and it is an important backup to GPS in case adversaries attempt to interfere with the satellite radio-navigation system.
The broadcast is on a number of shortwave frequencies, meaning their signals can be received globally.
www.voanews.com/a/time-may-be-running-out-for-millions-of....
Atomic Time
I took an hour today to drive out north of town to track down a little-known but very important facility critical to timekeeping in the USA.
WWVB is a time signal radio station near Fort Collins, Colorado and is operated by the National Institute of Standards and Technology (NIST). The station relies on extremely precise atomic clocks for the accuracy of the time signals. It sends out signals that allow millions of clocks and watches to be set either manually or automatically.
WWVB continuously broadcasts digital time codes, using very long electromagnetic waves at a frequency of 60 kilohertz, which are automatically received by timekeeping devices in North America, keeping them accurate to a fraction of a second. In 2011, NIST estimated the number of radio clocks and wristwatches equipped with a WWVB receiver at over 50 million.
Some argue the terrestrial time signal have been rendered obsolete by the government’s Global Positioning System, whose satellites also transmit time signals, but users disagree, noting GPS devices must have an unobstructed view of a number of satellites in space to properly function. Sixty kilohertz permeates in a way GPS can’t. WWVB’s very low frequency signal can be received inside buildings and it is an important backup to GPS in case adversaries attempt to interfere with the satellite radio-navigation system.
The broadcast is on a number of shortwave frequencies, meaning their signals can be received globally.
www.voanews.com/a/time-may-be-running-out-for-millions-of....