The BBC’s director general will be among the special guests as Crystal Palace switches off its analogue signal tonight.
Mark Thompson will be at the iconic tower as the transmitter, which broadcast the first colour images in 1956, is turned off for good.
The switchover to digital TV begins tomorrow and will be marked by the tower being lit up in a spectacular light show.
Broadcasters Sir David Attenborough and Professor Brian Cox will flip the switch at the tower to start the lights.
A new high-power digital TV transmission service will then be emitted by Arqiva from the iconic Crystal Palace broadcast tower.
Sir Attenborough said: “Thanks to public service broadcasting, for the past 75 years we could all take part in the most memorable moments in the UK’s history.
“Think about the coronation of Queen Elizabeth in 1953 or England winning the World Cup in 1966.
“Now with the switch to digital TV, we’re celebrating the start of a new, very exciting time in UK broadcasting when viewers will have more channels to choose from and a better viewing experience than ever before.
“This is as wonderful as anything I’ve experienced in my 60 years of working in the TV industry.”
John Cresswell, chief executive of Arqiva, said: “Digital switchover is the 21st century equivalent of the introduction of colour TV, bringing crystal-clear pictures, more channels and interactive features to the whole of the UK.
“With London’s rich history of broadcast firsts and almost five million homes served by Crystal Palace broadcast tower, London switchover is a very special moment in the nationwide switchover project.
“Behind the scenes, the scale of this national infrastructure project is immense. By completion in October we will have transformed a network that took 25 years build in only five years, transforming this vital public service into a modern platform that will meet the evolving TV viewing needs of the UK population.”