The radio signal used to set Britain's key clocks has a new home for the first time in 80 years.
Many industries depend on knowing the exact time
The signal which governs the "pips" heard on BBC radio services, moved from a site next to the M1 at Rugby, in Warwickshire, at midnight on Sunday.
Its new home is in Anthorn, Cumbria, after a change of contract.
The signal, used to manage a range of electronic networks such as for mobile and speed cameras, is kept in line by referencing two atomic clocks.
It is accurate to within 1,000th of a second of Coordinated Universal Time.
The MSF 60 kHz signal, as it is known, was transmitted from the Rugby Radio Station by BT under contract from NPL.
However, the contract was lost to VT Communications which will undertake the Anthorn transmission.
The signal, which has been beamed out of Rugby since 1927, is also used by the emergency services and to keep the clocks accurate in railway stations.
Many household clocks now also make use of the frequency to keep accurate time.
The system has been upgraded in its move to Cumbria. The switchover follows a three-month test period.
The National Physical Laboratory (NPL), which has been responsible for the Rugby signal since 1950, says the new transmitters at Anthorn will not require as much maintenance.
Despite the advent of satellite and on-line methods of accurate time-keeping, demand for the radio service has never been greater.
NPL managing director, Steve McQuillan has said that maintaining accurate time was essential for "keeping the modern world working".
"Most people only need time to be accurate to within a few seconds or even minutes, but global navigation systems, the internet, e-mail, television, the power industry, transport, and financial systems are just some of the industries that depend on very accurate time to operate."