Editing Time from NPL (MSF) (section)

== History ==
[[File:Rugby Anthorn MSF.jpg|thumb|Received, at Lesvos Island, during the transfer from Rugby to Anthorn]]
A radio station at Rugby was first operated by the [[General Post Office|Post Office]] from 1926, with the call-sign GBR. From 19 December 1927, it broadcast a 15.8&nbsp;kHz time signal from the [[Royal Observatory, Greenwich|Royal Observatory]] which could be received worldwide. It consisted of 306 pulses in the five minutes up to and including 10:00 and 18:00 [[Greenwich Mean Time|GMT]], with a longer pulse at the start of each minute. [[Frequency-shift keying]] was added in 1967, making the signal harder to use as a frequency reference. The time signals, preceded by the callsign "GBR GBR TIME" in [[Morse code]], were transmitted during the 5 minutes preceding 03:00, 09:00, 15:00 and 21:00. Transmitter GBZ on 19.6&nbsp;kHz was used as a reserve, when GBR was off-air for maintenance.<ref>{{cite book | author=Gerd Klawitter | title=List of Time Signal Stations | year=1980 | pages=30–31 | edition=9th }}</ref> Eventually, time signals from GBR were terminated in November 1986 and it is no longer used as a frequency reference.<ref name="faqs" />

The MSF signals started in 1950, following the transmission pattern [[#Protocol|described below]]. They were originally intended to provide frequency references at 2.5, 5 and 10&nbsp;MHz, originally only occasionally during the day. At first, there were announcements every fifteen minutes, beginning with the Morse code representation of "MSF MSF MSF" (MSF is "-- ··· ··-·" in Morse code), followed by speech "This is MSF, Rugby, England, transmitting ...".<ref>{{cite web|title=NPL Time Reference FAQ|url=http://www.npl.co.uk/science-technology/time-frequency/time/faqs/what-does-msf-stand-for-(faq-time)|publisher=NPL|access-date=20 January 2014|archive-date=22 April 2014|archive-url=https://web.archive.org/web/20140422133514/http://www.npl.co.uk/science-technology/time-frequency/time/faqs/what-does-msf-stand-for-(faq-time)|url-status=live}}</ref> From May 1953, the signal was broadcast 24 hours a day, but with regular five-minute stoppages to allow the reception of other signals. The 60&nbsp;kHz signal finally became an uninterrupted 24-hour service in 1966, and the frequency references were discontinued in February 1988.<ref name="faqs" />

On 27 February 2007 the NPL started tests of the new time signal transmissions from [[Anthorn Radio Station|Anthorn]].<ref>{{cite news
 | author = Kelly Eve
 | title = Time Begins in Anthorn Village
 | work = News & Star
 | location = Carlisle 
 | date = 28 February 2007
 | url = http://www.newsandstar.co.uk/news/viewarticle.aspx?id=471174
 | access-date = 28 February 2007 |archive-url = https://web.archive.org/web/20070810033940/http://www.newsandstar.co.uk/news/viewarticle.aspx?id=471174 <!-- Bot retrieved archive --> |archive-date = 10 August 2007}}</ref> The Anthorn station was operated by [[VT Communications]] from its opening in 2007 until 2010, when it was acquired by [[Babcock International]].<ref name=siginfo>{{cite web|url=https://www.npl.co.uk/msf-signal|title=MSF Radio Time Signal|access-date=1 May 2022|publisher=[[National Physical Laboratory (United Kingdom)|National Physical Laboratory]]|archive-date=2019-07-05|archive-url=https://web.archive.org/web/20190705131618/https://www.npl.co.uk/msf-signal|url-status=live}} General and technical information, advice on reception problems, and up-to-date information on signal outages and scheduled maintenance</ref>

The formal inauguration of the relocated facility took place on 1 April 2007, when the name of the service became "The Time from NPL" and the signal from Rugby was permanently switched off.<ref>{{cite news
|title=Times changing for radio signal
|author=Pallab Ghosh
|work=BBC News Online
|date=10 May 2006
|url=http://news.bbc.co.uk/1/hi/sci/tech/4756593.stm
|access-date=28 March 2007
|archive-date=2 January 2007
|archive-url=https://web.archive.org/web/20070102110717/http://news.bbc.co.uk/1/hi/sci/tech/4756593.stm
|url-status=live
}}</ref><ref>{{cite news
|title=Time change marks end of an era
|work=BBC News Online
|date=25 March 2007
|url=http://news.bbc.co.uk/1/hi/sci/tech/6483969.stm
|access-date=28 March 2007
|archive-date=27 March 2007
|archive-url=https://web.archive.org/web/20070327132755/http://news.bbc.co.uk/1/hi/sci/tech/6483969.stm
|url-status=live
}}</ref> The change in location and consequent change in signal strength can make some equipment designed to use the MSF signal fail to continue doing so. This is found more in domestic equipment not designed for optimum sensitivity and positioned haphazardly.{{Citation needed|date=November 2011}}
Currently, the signal from Anthorn is still usable, in the location of the Mediterranean, although it is weaker than Rugby.