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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.
Contents
- Technical information
- Audio accompaniment
- Bubbles the Clown
- Colour
- Test Card J
- Test Card W
- BBC HD channel variant Test Card X
- BBC TWO variant 2016
- Recent years
- In popular culture
- Television
- Other
- References
The central image on the card shows eight-year-old Carole Hersee (born 1958) playing noughts and crosses with a clown doll, Bubbles the Clown, surrounded by various greyscales and colour test signals needed to ensure a correct 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 a BBC engineer, George Hersee (1924–2001), father of the girl in the central image. It was frequently broadcast during downtime on BBC1 until that channel went fully 24 hours in November 1997, and on BBC Two until its downtime was replaced entirely by Pages from Ceefax in 1998, after which it was only seen during engineering work, and was last seen in this role in 1999. The card was also seen on ITV in the 1970s. It was also seen on Sveriges Television in an unknown time period.
In the digital age Test Card F and its variants are very infrequently broadcast, as downtime in schedules has largely become a thing of the past. 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 switchover, the testcard made an annual 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 tests are found on the left and right respectively of the central picture. On the updated Test Card J, 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.
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.
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; liquid crystal displays (LCDs), that are not scanned at high speed, also help. 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 and the other the monochrome background. 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 sometimes music, usually a composition commissioned by the station itself or "royalty-free" stock music. Composers whose music has been used include Roger Roger, Johnny Pearson, Neil Richardson and Frank Chacksfield.
However, during more recent years in which the Test Card is only played during engineering tests on the BBC, it is more common to hear a steady tone of various pitches accompanied by a female talking clock. Test Card music had ceased to be frequently heard in the 1980s (though it continued to be played over Pages from Ceefax until the termination of that service on 23 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, which is more than any living person other than Carole (who still owns Bubbles).
Colour
Bubbles' original body colour was blue and white, but the BBC engineers decided that green was also needed within the scene as the other two television primary colours, red and blue, were already shown. A green wrap was made to cover his body and this can be seen in Test Card J and Test Card W, along with more of his body shown in the photograph — revealing the fact that he is actually holding a piece of chalk, which was not previously visible.
However, the shade of green material chosen was too subtle for the engineers' liking and so Bubbles' body colour in Test Card F was retouched (this can be seen from the edges of his image) to make it more saturated and also to give it a higher luminance value on screen.
Test Card J
Test Card J is an updated version of Test Card F, and first appeared in November 1999. It includes the following changes relative to its predecessor:
Test Card W
Test Card W is an updated 16:9 (1.78:1) widescreen version of Test Card F. It first appeared in November 1999 alongside Test Card J, with which it bears some similarities.
The colour-bars on the top and right of the image are the full 100 percent saturation version, unlike Test Cards F and J which use the 95 percent type. Extra mirrored arrow-heads on the central axis at the sides mark the positions of the middle 4:3 and 14:9 sections of the image.
On Freeview in the United Kingdom, Test Card W can be viewed at any time on most Freeview boxes.
BBC HD channel variant ("Test Card X")
A 1080 line variant of Test Card W (sometimes referred to unofficially as Test Card X) was used on the now-defunct BBC HD channel. It could be viewed every two hours as part of the BBC HD preview slot. When viewed, it was enhanced with 5.1 surround sound tests. A BLITS tone is played alongside, which plays test tones at different frequencies from each of the different surround sound speakers, with markers (such as L, R, C, LFE, Ls, Rs) appearing inside some of the grey boxes of the testcard. BBC HD closed in March 2013; therefore Test Card X is no longer broadcast.
BBC TWO variant (2016)
The latest (2016) iteration of the widescreen testcard can been seen briefly each morning on BBC TWO and BBC TWO HD. At the centre bottom of the test card is an animated grey bar with graduations corresponding to 1/12 of a second. The animation is accompanied by a 'pip' that occurs when the animated bar reaches the centre mark (indicated by a 0), which together can be used to determine whether the digital audio and video signals are synchronised.
Recent years
Since the late 1990s, Bubbles has only very rarely appeared on television as Test Card F has been discontinued, and Test Cards J and W are very seldom shown due to the advent of digital television and 24-hour programming.
From 1983 Test Card F was gradually seen less due to Ceefax pages being shown more; by the late 1980s Test Card F was only seen early in the morning as all the remaining gaps in the day's programming were filled with programmes. 1992 was the last year that Test Card F was seen daily with music; 1995 was the last year it was seen with music, although it was seen until 1999 with just tone output; CEEFAX was broadcast either with tone or music. However, since the closure of CEEFAX, the shutdown of analogue television transmissions, and the imposition budgetary constraints, a new revision of the testcard can be seen daily on BBC TWO and BBC TWO HD at the end of the "This is BBC TWO" transmission. Each morning, as the segment concludes, the testcard is broadcast for approximately one minute.
For the fortieth anniversary of Test Card F, there was some renewed interest in Bubbles in the media; in a 2007 interview, Hersee mentioned that she took Bubbles into school with her to prove to her headmaster that she really was the girl in the picture.
The BBC website (as of April 2016) continues to feature Bubbles next to a blackboard with "404" inscribed on it when a user visits a page that does not exist. Similarly, the BBC website's "500" Internal Error page features Bubbles crossed-eyed next to a blackboard but with fire in the background.
In popular culture
Variations and parodies of Test Card F are common in British broadcasting, Internet sites and games.