Greenwich Time Signal broadcasts the pips every hour. Pips can also be heard on many BBC Local Radio stations although their use is up to the discretion of individual stations. A rare quarter-hour Greenwich Time Signal can be heard at 05:15 weekdays on Wally Webb's programme on six BBC Local Radio stations in the east of England, as part of his "sychronised cup of tea" feature. In 1999, pip-like sounds were incorporated into the themes written by composer David Lowe to introduce BBC Television News programmes. They are still used today on BBC One, BBC World News and BBC News. The BBC does
Greenwich Time Signal the leap second thus justifies the final pip being longer than the others, so that it is always clear which pip is on the hour. Before leap seconds were conceived, the final pip was the same length as the others. Although "negative" leap seconds can also be used to make the year shorter, this has never happened in practice. Although normally broadcast only on the hour by BBC domestic radio, BBC World Service use the signal at other times as well. The signal is generated at each quarter-hour and has on occasion been broadcast in error. Up to 1972 the