> Bill, > WWVB added a new modulation format starting around 2012/13 that includes a > phase shift that some older clocks can > no longer resolve.
Gary, The 2012 addition of BPSK modulation doesn't affect WWVB-controlled clocks -- only older carrier phase tracking receivers that use WWVB as a frequency reference that were designed prior to the October 29, 2012 modulation format change. NIST has several receivers scattered around the country that monitor WWVB signal levels, 24 hours a day. You can check the status any time by going here: https://tf.nist.gov/tf-cgi/wwvbmonitor_e.cgi Occasionally, WWVB is taken off the air for brief periods of time. Information on outages can be found here: https://www.nist.gov/pml/time-and-frequency-division/radio-stations/wwvb/wwvb-station-outages NIST Special Publication 250-67 provides technical details regarding the transmitters, feedlines, antenna systems, and routine maintenance procedures employed at WWV, WWVB, and WWVH. 73 de John, KD2BD ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
