The iconic Crystal Palace broadcast tower is no longer transmitting analogue signals.

At just after midnight today, more than seventy-five years of analogue TV broadcasts in London came to a close, when the signal at the landmark venue was switched off.

CEO of transmission provider Arqiva, John Cresswell, was joined at the 219 metre-high tower by BBC director general Mark Thompson, to flick the 'off' switch to analogue and turn on the new, high-power digital TV signal.

Crystal Palace and 52 relay transmitters across London and the Home Counties - from St Albans to Dorking - switched to the new system for Freeview, reaching into five million homes across the capital and beyond.

It is hoped the new signals, with 10 times the power of the current digital TV service, will reach more than 400,000 viewers in coverage blackspots.

To mark the switchover, a huge lightshow will take place at the Crystal Palace broadcast tower tonight and tomorrow.

Facts and figures

• More than 200,000 watts – 7.5 billion candlepower – of energy-efficient lighting, the same wattage used to light the Eiffel Tower in Paris, has been installed in readiness for the lightshows.

• At 9.15pm tonight (April 18) Sir David Attenborough and Professor Brian Cox will push the button to illuminate the 219-metre tall structure.

• Visible across London, the explosion of light will culminate with a beam of light shooting up the tower and radiating out over London, representing the invisible digital TV signals.

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