Pip pip hooray!
Wednesday 5 February 2014 marks 90 years since the BBC first broadcast the six pip radio time signal.
The radio 'time pips' are most famously heard on BBC Radio 4 on the five seconds leading up to the hour and the hour itself. They are generated by a Time and Frequency distribution system housed at the BBC, which is kept in step by a combination of GPS signals and the 60 kHz MSF Time signal, broadcast from Anthorn radio station in Cumbria and based on the NPL time scale UTC(NPL).
UTC(NPL) is the UK's national time scale and is generated from a group of atomic clocks operated at NPL. As the UK's centre of precise time and frequency measurement, NPL offers a range of services that provide access to a reliable and trusted source of time and was recently named the birthplace of atomic timekeeping by the European Physical Society.
On 5 February 2014, BBC Radio 4 played a special happy birthday version of the radio time pips to celebrate their 90th anniversary.
More on the MSF time signal