Wales will become the first part of the UK to have a fully digital TV service today.
The principality's last analogue television transmitters started switching off at midnight, leaving every viewer with a digital signal.
By the end of the day, anyone who has not changed to digital TV providers like Freeview and Sky TV will lose their television service.
The Wenvoe transmitter near Cardiff and its 75 relay stations, which serve 649,000 homes in south-east Wales, are being shut down.
Wales's switchover began in Swansea in August last year, followed by mid and north Wales, with Wenvoe the last of eight transmitter groups being closed.
Emyr Hughes, Digital UK's national manager for the country, said the switchover had gone well with 98.4% of households in Wales having digital television after the switch.
The others did not have analogue television to start with, he added.
Mr Hughes told the BBC: "It's been fine. Most people managed it without any difficulty at all. There was quite high satellite coverage in Wales to start with.
"I can't think of any instances where there's people who were unhappy with digital television but there were some people who found it a bit more challenging because they had unusual equipment, or elderly people who needed a bit more support."
Other parts of the UK will see their switchover start over the coming years.
Most of Scotland will change later this year and next, with the likes of London, Tyne Tees and Northern Ireland regions waiting until 2012.
Under a government-backed scheme, elderly and vulnerable people have been given help to make the switchover.
The Wenvoe transmitter and its relay stations cover an area including Cardiff, Newport, Monmouth, Merthyr Tydfil, Brecon and Rhondda Cynon Taf.