STANDARD FREQUENCY and TIME SIGNAL STATIONS on LF and HF Originally Published Between October 1997 and July 1998
WUN ARCHIVE STANDARD FREQUENCY AND TIME SIGNAL STATIONS ON LF AND HF Originally published between October 1997 and July 1998 Standard frequency and time signal stations on LF and HF, pt.1 Welcome to the first part of a series about Time and Frequency Stations on LF and HF. This month you'll find a frequency list and a general introduction to these stations. During the next few months, we will highlight a bunch of the stations. Special thanks to Klaus Betke for his research, Stan Skalsky, Kevin Carey, Terry Krey, and Dave Mills. Also thanks to the Institute of Meteorology for Time and Space (Russia), BIPM Bureau International des Poids et Mesures (France) and NIST National Institute of Standards and Technology (USA) for their time, help and the huge amount of info. Introduction Exact time intervals are needed for navigation and surveying, in science and engineering. In the past, HF radio signals were often the only way to calibrate a clock onboard a ship or a frequency standard in a laboratory. In the age of GPS satellites and portable atomic clocks, however, time and frequency distribution via HF has become largely obsolete. New applications like network synchronization require an accuracy that cannot be met by HF signals. Moreover, the transmission scheme of most stations and the peculiarity of shortwave propagation make these signals less suitable for automatic, unattended reception. Consequently, many time signal stations have disappeared. In former times, coastal radio stations also transmitted time signals on their CW frequencies. Although numerous of these services to mariners are still listed in, you will hardly find an active one.
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