The Pips: The Greenwich Time Signal Explained
The pips are the short beeps broadcast on BBC radio at the top of the hour. They are officially called the Greenwich Time Signal.
How they work
The signal is six tones: five short pips and one longer. The start of the final, longer tone marks the exact hour. It was first broadcast by the BBC in 1924 and has been a fixture of British radio since.
Why digital radio can be late
Digital radio and streaming involve processing and buffering, so the pips can arrive several seconds after the real hour. FM and long-wave are closer to the true time, which is why the signal is a poor way to set a precise clock on a digital service.
Frequently asked questions
When did the pips start?
The BBC first broadcast the Greenwich Time Signal in 1924.