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Science Museum Group
© The Board of Trustees of the Science Museum
CEEFAX clock Serial No. 1 GE7/7.
This unit generated the clock for broadcast in the BBC’s onscreen text information service CEEFAX. Accurate time information was provided by the MSF receiver, contained in a weatherproof box, which was fed to the rack unit.
CEEFAX was the first teletext service, transmitting data in the television transmission vertical blanking interval. It was launched by the BBC on 23 September 1974. The onscreen graphic pages provided information, including up-to-date news and services such as subtitling. CEEFAX ended following the closure of analogue transmissions in 2012.
The MSF signal is the national time reference. The time signal is controlled by caesium atomic clocks and was broadcast from Rugby Radio Station until 2007.
MSF is the morse code sent as part of the time signal and CEEFAX is a pun on ‘see facts’, neither are acronyms.
Details
- Category:
- Television
- Collection:
- BBC Heritage Collection
- Object Number:
- 2012-5118/603
- Materials:
- plastic (unidentified), metal (unknown) and electronic components
- Measurements:
-
overall: 225 mm x 485 mm x 410 mm, 5.5 kg
- type:
- clock
