Celebrating the BBC pips: Greenwich Time Signal

The Greenwich Time Signal (also known as "the pips") was used by many BBC Radio stations between 1924 and 1990.

The six-pip Time Signal was introduced on 5 February 1924 following the successful broadcast of the chimes of Big Ben to usher in the new year.

For 84 years the major global news headlines of the day have been preceded by the six Greenwich Time 'pips'.

When the BBC broadcast the news of Neil Armstrong’s first steps on the Moon, President John F Kennedy’s assassination, and the destruction of the Berlin Wall, they followed the familiar sound of the Greenwich pips.

What is the Greenwich Time Signal?

The Greenwich Time Signal (GTS) is also known as the BBC's six-pips. The British national broadcaster transmitted six short-tones at one-second intervals to mark a new hour.

Several BBC local radio stations used the six-pips or almost a century, between 1924 and 1990, before the system being changed.

Where is the original six pip clock? 

The original clock used for the six-pips signal, known as the 'Pip pip Clock' is currently kept at the Royal Observatory Greenwich.

The Royal Observatory Greenwich Time Galleries
The Royal Observatory Greenwich Time Galleries

Key facts

  • The clock is regulator number 2016 by Dent of London. Dent of London are also the makers of Big Ben. 
  • The pip pip clock was made in 1874 for use across the globe when observing the Transit of Venus astronomical phenomenon that year, before moving to Greenwich.
  • It was the very first to provide the six-pip signals in 1924 with pendulum roller contacts, which are still in the Observatory collection.

Visit the Pip pip clock

What's the story of the six-pip Time Signal?

Late in 1923, Frank Dyson, ninth Astronomer Royal, visited John Reith, Director General of the BBC, to discuss the idea of public time signals being broadcast. The six-pip Time Signal (pips for seconds 55, 56, 57, 58, 59, 60) was Dyson’s brain-child. It was devised in discussion with Frank Hope-Jones, inventor of the free pendulum clock, who had originally advocated a five-pip signal.

In 1939, the six-pip signal and the Time Service moved from Greenwich to the magnetic observatory at Abinger in Surrey. They then moved to Herstmonceux, Sussex in 1957.

In 1990, the Greenwich Time Signal transmitted its last pips. Since then the BBC has originated its own pips based on signals from the GPS satellite network and from the 60kHz radio transmitter at Anthorn, Cumbria.