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June 1979 - April 1986

Idents/Clocks [1]

The first electronically-generated BBC television ident came on to our screens in June 1979. It is reported that an off-air recording shows the ident in use on Saturday 23rd June 1979 and that the only known off-air footage prior to that is from Saturday 9th June 1979, where the ident introduced in late-1974 still features in junctions. We have not seen either recording and so are unable to comment on the validity of these dates.

The ident was designed in-house by Oliver Elmes and was playout out from a solid-state box of electronics, put together by BBC engineers. Although static for most programme links, the ident could animate in two ways: (a) starting from a black screen, the double orange lines would scroll into view from the left, followed by each of the two lines that made up the '2' (in turn) and rounding off with the appearance of the second set of double orange lines, from left to right; (b) with the ident fully formed, it would animate out of view, from left to right - executed in a similar style to the first animation. The first animation described here was definitely the more common of the two. It may seem logical to conclude that the second animation would be a common feature of the nightly closedown - not so. BBC Two's closedown routine generally featured the channel's clock device: the announcer would bid us goodnight over the clock and fade to black or, alternatively, fire up some music on the gram machine and work through a series of slides (typically scenic shots), before fading to black. That said, we are aware that on some occasions, the slide show would round off with an appearance of the ident and the lesser-spotted second animation.

One curious characteristic of the ident which most viewers and many enthusiasts will have been oblivious to is the presence of a small white vertical line on the far left near the bottom of the screen, during animation (a). The line is actually present, pre-animation, when the screen is empty/black. This was not a fault. It is believed that it was a way of confirming that the ident output had been successfully put to air, prior to the start of the animation; particularly useful if the ident's output had been faded up from black, which was very common following trade test transmissions and promotional trails. The white line disappears when animation (a) completes and interestingly, the first vertical line of pixels of the orange stripes on the far left of screen also appear when the white line disappears; this may well have been a minor glitch. However, these little oddities would have been out-of-view on most domestic television sets, as they were at the extreme edge of the picture.

From its introduction in June 1979 until c. September 1983, the ident was occasionally accompanied by an audio fanfare. Usage of the fanfare was generally restricted to the first appearance of the ident each day and where BBC Two came back on air later the same day, after a period of closedown/trade test transmission. We say 'generally' because this was not always the case. But apart from these two scenarios, the fanfare was not used. The fanfare lasted about 7 seconds, versus the 3-second animation of the ident - so, not a perfect fit. In an attempt to get around the disparity between the two, many announcers would initiate the fanfare a couple of seconds prior to kicking off the ident animation.

Above: BBC Two ident [1]. Here we see animation (a).

Above: BBC Two ident [2]. And this is the less common animation (b).

Above: BBC Two ident [3] - Ceefax 270. BBC Two ident [4] - Ceefax 888. Teletext subtitles were highlighted by means of 'CEEFAX 270' (and later 'CEEFAX 888') text being overlaid on the symbol.

Above: BBC Two ident [5] - Schools. Schools programmes moved to BBC Two in September 1983; a new version of the BBC Two symbol was introduced for the new 'Daytime on 2' strand.

Above: BBC Two schools countdown [1]. Prior to autumn 1983, Schools programmes occasionally had reason to move to BBC Two for the day. In such circumstances, a special version of the 'Dots' countdown was required. In this example, we see the electronically-generated dots (used on BBC One) with the '==2==' logo keyed on top.

Above: Open University ident [1]. The animation of the OU logo was produced using a mechanical device. Unfortunately, we don't have any footage of the animation at present.

Above: Open University ident [2]. This electronically-generated version of the OU ident is thought to have been introduced at the same time as the electronic clock device, on Saturday 6th September 1980 and remained in use until 1984.

The Open University strand also had its own clock, featuring the same yellow and blue colour scheme. If you have any footage of this clock, we'd like to hear from you.

Above: Open University ident [3]. This OU symbol was introduced in 1984, exact date unknown

Above: Open University ident [4].

Above: BBC Two clock [1]. The mechanical model in use between late-1974 and June 1979 was recoloured and updated with the new stripy BBC Two logo. This all looked very primitive alongside the slick, new electronically-generated channel symbol.

Above: BBC Two clock [2]. Introducing 'News on 2'.

Above: BBC Two clock [3]. At closedown.

Above: BBC Two clock [4]. Leading into an afternoon trade test transmission.

Above: BBC Two clock [5]. On Saturday 6th September 1980, BBC Two got a nice, shiny, new and entirely electronically-generated timepiece. There were one or two teething problems with new kit and the mechanical clock was still 'on hand' to cover. The change of technology also saw the introduction of an updated clock face design, with new hour markers and a small, solid circle in the centre.

The project to replace the Noddy-based clock caption device (where a camera was placed in front of a mechanical clock and colour added by a colour synthesiser) was initiated in 1979 after John Shelley spotted an article in the Engineering Weekly Information Sheet, where the various problems with keeping the clock camera correctly adjusted were outlined. John sent a handwritten note to Richard Russell of the Designs Department saying simply "This all seems pretty primitive. Is there a possibility that we could generate the clock caption electronically?".

When built, the new electronic kit was put on display at the BBC's stand at the IBC (International Broadcasting Convention) in Brighton in 1980. BBC Engineering produced the following article on the new development, which provides some fascinating insights:

From Saturday 6th September, the clock seen on BBC Two has been produced electronically. The BBC One clock is expected to 'go electronic' next year. The new BBC system, designed by Richard Russell of the Designs Department, has done away with the need for cameras, slide scanners and mechanical clocks. Richard Russell says "the new clock has been designed to take up less space, to be less costly to operate and to be more reliable and to offer better resolution than the system it has replaced."

The picture the viewer sees is made up of the clock and the BBC logo, showing him which channel he is watching. The network logo for BBC Two is generated using run-length encoding, where the data is stored in a programmable read-only memory (PROM). Run-length encoding is where, instead of telling each picture element what colour it should be, it is only necessary at each colour change to tell the system how long the colour will last, i.e., its 'run-length'. Although theoretically 1,024 colour changes could take place on each line, this is limited by the size and speed of the data memory. The use of a buffer memory permits at least 64 changes on each line.

The run-length data for the BBC Two logo has been produced by John Mitchell of the Television Investigation Section. Robin Vinson and Ewen MacLaine of the Computer Graphics Workshop produced the data for the Open University symbol on BBC Two, which is also generated by the new equipment.

The logo generator can operate in two modes. The first limits the system to four different colours and reduces the size of the memory needed to a minimum. The other makes 32 different colours possible but as a result needs a much larger memory. For example, it needs about 4 kilobytes of memory storage to display a simple logo.

An additional feature of the BBC logo generator is that it can be used to produce simple animation. Although it is mainly intended to produce fixed patterns by reading run-length data from a PROM, movement can be achieved by using a microprocessor to make real-time alterations to the data held in a random access memory (RAM). The system reads the data from the RAM by means of direct memory access (DMA).

The main part of the picture - the electronically generated clock - is made up of two components: the fixed elements on the clock face and its moving hands. The fixed elements - hour markers, the circle and the centre spot - are stored in a PROM as a series of horizontal position coordinates which are read out in sync with the television waveform. The size of the memory required is reduced by using horizontal and vertical symmetry.

The data for the clock hands is stored in a RAM. A microprocessor controlled by an erasable programmable read-only memory (EPROM) keeps track of the time and every second calculates the correct angle of the hour, minute and second hands.

The BBC designers had to get over the problem that when the hands made only a small angle to the horizontal, the television line structure breaks the edge of the hands up into a staircase. The BBC's answer is to feed the hand signals through analogue processing circuitry which adjusts the rise and fall times of the waveform according to the angle of each hand. The microprocessor then selects the rise time to give the best optical effect on the viewers' screen.

All the equipment needs is mixed blanking and mixed sync pulses together with AC mains power. However, time reference pulses and logo-selection signals for remote control can be used as optional inputs. Without an external time reference signal, the clock derives its reference from either incoming television pulses or from its own internal oscillator. The outputs are standard 0.7 volt peak-to-peak RGB and a composite monochrome output suitable for feeding to a colour synthesiser.

The clock can be set to any time. It can be corrected in one-second intervals or by the hour - useful for the twice yearly changes between GMT and BST.

Above: BBC Two clock [6]. Taken from a link into 'Sunday Grandstand'.

Above: BBC Two clock [7]. At closedown.

Above: BBC Two clock [8]. In the 1980s, BBC Two often showed a series of scenic shots accompanied by music as part of the closedown sequence. Occasionally, the clock that preceded such sequences would have the first scenic slide as a background image.

Above: BBC Two clock [9]. As far as we know, the Open University strand did not have its own clock from 1984 onwards. However, this adapted version of the standard BBC Two clock was used occasionally as a filler, prior to the start of late-night weekday broadcasts.