Greenwich Time Signal Greenwich Time Signal The Greenwich Time Signal (GTS), popularly known as the pips, is a series of six short tones broadcast at one-second intervals by many BBC Radio stations. The pips were introduced in 1924 and have been generated by the BBC since 1990 to mark the precise start of each hour. Their utility in calibration is diminishing as digital broadcasting entails time lags. There are six pips (short beeps) in total, which occur on each of the 5 seconds leading up to the hour and on the hour itself. Each pip is a 1 kHz tone (about halfway between
Time signal Observatory as a source of time signals: The telegraphic distribution of time signals was made obsolete by the use of AM, FM, shortwave radio, Internet Network Time Protocol servers as well as atomic clocks in satellite navigation systems. Since 1905 time signals have been transmitted by radio. There are dedicated radio time signal stations around the world. Time stations operating in the longwave radio band have highly predictable radio propagation characteristics, which gives low uncertainty in the received time signals. Stations operating in the shortwave band can cover wider areas with relatively low-power transmitters, but the varying distance that the