WWVB Tests Phase Modulation

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WWVB Tests Phase Modulation

Jun 12, 2012 11:13 AM

Ft. Collins, CO - Jun 12, 2012 - The National Institute of Standards and Technology (NIST) operates radio station WWVB on the same site as WWV near Fort Collins, CO. The WWVB broadcasts are used by millions of people throughout North America to synchronize consumer electronic clock products. In addition, WWVB is used for high-level applications such as network time synchronization and frequency calibrations. The station transmits an AM signal on 60kHz.

The NIST is currently testing phase modulation in addition to the existing amplitude modulation on WWVB. The AM signal continues while the PM is tested, so there should not be any interruption in service to existing AM devices, although the NIST warns that phase-locked loop (PLL) devices AM devices may lose signal lock at times during the tests.

Previous tests have been held in March 2012 and the most recent (as of this writing) was held June 7, 2012. The next experiment is planned to start on June 14 and will run for 15 consecutive days, ending June 29. The test will end prior to the June 30, 2012, leap second correction.

If the extended test is deemed a success, WWVB plans to permanently add PM in August or September.

Questions or comments can be forwarded to WWVB Broadcast Manager John Lowe at 303-497-5453 or john.lowe@nist.gov.