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five, four, three, two, one
17 January 2022 tbs.pm/74458
Time in television is a dimension which must be constantly metered, measured, displayed and costed by those engaged in the industry.
Within the present network of companies, there is no one controlling centre. Each programme is started and run by the contributor to a pre-arranged Master Time Schedule. Local advertising material is inserted, again to the Master Schedule. It is therefore essential for time to be accurate to the second.
There is a battery-driven Master Pendulum clock in a basement room in Anglia House, corrected automatically to Greenwich time signals by a crystal controlled radio receiver switched on twice a day for the ‘pips’ which are filtered out and compared with six pulses from the clock. Any error is reduced to zero during the ensuing four hours.
Two sources of error were found with the clock after installation; a long-term drift was expected, but random jumps were not. The automatic corrector unit smoothed out the drift, but the jumps could not be explained even after close inspection of the master unit. Moving it to another wall effected a cure. The original wall adjoins an echo chamber used by the Sound Department for musical effects and it was thought that the simple harmonic motion of the pendulum was upset by the more complex harmonious motion of the wall.
An example of the Greenwich ‘pips’ on BBC Radio 2 from 1968, before the elongated final ‘pip’ was added.
Studio clocks require a diameter of 3 ft. [0.9m], silent operation and ease of viewing. Clocks used in control rooms are discreetly illuminated and so placed that the least eye movement is necessary between clock and monitor. This helps engineering and production personnel to concentrate on time and picture. This is particularly important in the Continuity Studio, where an announcer linking programmes must conform to precise timing. He must look into the camera lens against strong lighting and yet be able to see the clock’s second hand. This is achieved by combining the clock and monitor unit under the lens itself, the clock illuminations being carefully balanced.
Where the programmes contain film or ampex sequences strict timing is of prime importance if the final programme is to be a smoothly finished product. This is done by accurately measuring the film so that the duration is known and by visible signals, known as cue-dots, which are placed in the top-right hand corner of the picture to indicate that only a few seconds remain. The cue-dot gives a visual sign that the recording will end shortly and is a check to the previous timing of the sequence.
It has been said that ‘Silence is Golden’. Perhaps in television, where advertising is sold in seconds and programmes measured in terms of time, it would be more accurate to say that ‘Time is Golden’.
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