There has been much research in recent years into the use of optic fibre cables, and the department has been heavily involved in the development of these cables for the transmission of audio and visual signals.
Optic fibres are made from a very high grade silica glass, so pure that a window pane 100 metres thick would let through more light than a 3mm window pane of conventional glass. When bundled and stretched into lengths, optic fibre cables are considerably more compact and efficient than the copper cables now in general use.
Being non-metallic, optic fibres do not suffer from electrical interference and are quite impervious to water, the two natural hazards that most commonly hamper outside broadcast units.
On a location such as Sandown Park racecourse, there is a permanent installation of copper cable jointly maintained by Thames and London Weekend Television. Thames’ engineers plan to solve interference problems by replacing this system with optic fibre cables carrying up to ten channels of sound, six for communication with the control room and four for transmission.