Test Card F is a test card that was created by the BBC and used on television in the United Kingdom and in countries elsewhere in the world for more than four decades. Like other test cards, it was usually shown while no programmes were being broadcast. It was the first to be transmitted in colour in the UK and the first to feature a person, and has become an iconic British image regularly subject to parody. The central image on the card shows Carole Hersee playing noughts and crosses with a clown doll, Bubbles the Clown, surrounded by various greyscales and colour test signals used to assess the quality of the transmitted picture. It was first broadcast on 2 July 1967 (the day after the first colour pictures appeared to the public on television) on BBC2. The card was developed by BBC engineer George Hersee (1924–2001)—Carole's father. It was frequently broadcast during daytime downtime on BBC Television until 29 April 1983, when it was replaced with broadcasts of Ceefax pages. It continued to be seen for around 7.5 minutes each day before the start of Ceefax broadcasts but it would also be shown on days when the Ceefax generator was not working. It was further phased out from BBC1 in November 1997 when the station began to air 24 hours a day, followed by BBC2 in January 1999 when its overnight downtime was replaced entirely by Pages from Ceefax. After then it was only seen during engineering work, and was last seen in this role in 2011. The card was also seen on ITV in the 1970s, occasionally used in conjunction with Test Card G. In the digital age, Test Card F and its variants are very infrequently broadcast, as downtime hours in schedules have largely been discontinued. Several variations of TCF have been screened, among them Test Card J (digitally enhanced), Test Card W (widescreen) and its high definition variant, which is sometimes erroneously referred to as Test Card X. Up until the UK's digital television transition in 2010–2012, the test card made an appearance during the annual RBS (rebroadcast standby) Test Transmissions and, until 2013, during the BBC HD preview loop, which used Test Card W.
Technical information Virtually all the designs and patterns on the card have some significance. Along the top (see above) are 95% saturation colour bars in descending order of luminance—white, yellow, cyan, green, magenta, red, blue and black. There are triangles on each of the four sides of the card to check for correct overscanning of the picture. Standard greyscale and frequency response (1.5, 2.5, 3.5, 4, 4.5 and 5.25 MHz) tests are found on the left and right respectively of the central picture. On the updated version known as Test Card J (including widescreen and HD versions), the X on the noughts-and-crosses board is an indicator for aligning the centre of the screen. The blocks of colour on the sides would cause the picture to tear horizontally if the sync circuits were not adjusted properly. The closely spaced lines in various parts of the screen allowed focus to be checked from centre to edge; mistuning would also blur the lines. All parts of the greyscale would not be distinct if contrast and brightness (both internal preset settings and user adjustments) were not set correctly. The black bar on a white background revealed ringing and signal reflections. The castellations along the top and bottom also revealed possible setup problems. In the centre image, a child was depicted so that wrong skin colour would be obvious and not subject to changing make-up fashions. The juxtaposed garish colours of the clown were such that a common transmission error called chrominance/luminance delay inequality would make the clown's yellow buttons turn white. Use of centre images in test cards were however not a new idea; RTF and ORTF in France used the Marly Horses as the central motif of its monochrome 819-line test card which was used on TF1 between 1953 and 1983, and the first French colour test card featuring a centre image of colourful roses was used on France 2 from 1967 until sometime around the mid-1970s. SVT in Sweden was also later inspired by Test Card F to develop its own colour test card, based on its earlier monochrome test cards, with a girl holding a doll in the centre image. Modern circuitry using large-scale integration is much less susceptible to most of these problems. Some of them are also associated with cathode-ray tubes; modern screens use liquid crystal displays (LCDs) that are not scanned at high speed. The test card was a vital tool in its day, but has become far less important. The name of the broadcasting channel usually appeared in the space underneath the letter F—a sans-serif F denoting an original optical version of the test card. Originally, Test Card F was a photographic slide made up of two transparencies in perfect registration—one containing the colour information (chrominance) and the other the monochrome background (luminance). The card was converted to electronic form in 1984 when electronic storage became possible.
Audio accompaniment
A sound of some kind is usually transmitted in the background. It is either music, usually a composition commissioned by the station itself or "royalty-free" stock music, or a steady tone. Composers whose music has been used include Roger Roger, Johnny Pearson, Neil Richardson, Frank Chacksfield, Syd Dale, John Cameron, Brian Bennett, Keith Mansfield, and Alan Hawkshaw. In recent years, the Test Card is only shown during engineering tests on the BBC and is accompanied by a steady tone of various pitches accompanied by a female talking clock. Test Card music had ceased to be frequently heard with the test card by the end of the 1980s, although it continued to be played over Pages from Ceefax until the termination of that service on 22 October 2012.
Bubbles the Clown
Along with his Test Card F co-star Carole Hersee, Bubbles has appeared for an estimated total of 70,000 hours on television, equivalent to nearly eight whole years. Carole still owns Bubbles.
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