Greenwich Time Signal not allow the pips to be broadcast except as a time signal. Radio plays and comedies which have fictional news programmes use various methods to avoid playing the full six pips, ranging from simply fading in the pips to a version played on "On the Hour" in which the sound was made into a small tune between the pips. "The News Quiz" also featured a special Christmas pantomime edition where the pips went missing, and the problem was avoided there by only playing individual pips and not the whole set. The 2012 project "Radio Reunited", however, did use the pips
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