The operators of a transmitter which serves part of northern England cannot say when it will be fixed.
TV and radio services for more than a million people will remain off air indefinitely after a transmitter fire.
The blaze at the Bilsdale mast on Tuesday disrupted Freeview, DAB and FM radio signals across North Yorkshire, Teesside and parts of County Durham.
Operator Arqiva said it would bring in temporary equipment but could not say when services would be restored.
Witness Ron Needham, 71, reported seeing “a huge black cloud of smoke come from the buildings at the bottom”.
He had been hiking on the North York Moors with his wife Sue, 69, when they stopped for lunch at the base of the mast.
They noticed “nothing untoward” but after continuing for about a mile and a half noticed smoke coming from the top “like a chimney”, Mr Needham said.
Despite the loss of transmission from the tower, BBC television remains available on iPlayer.
Radio stations can still be listened to on BBC Sounds.
Firefighters were sent to the site at 13:19 BST on Tuesday after a call from an engineer working on the transmitter near Helmsley.
North Yorkshire Fire and Rescue Service said there were “concerns about the structural integrity of the mast” and a 300m (980ft) exclusion zone is in place around it.
Arqiva confirmed that no-one was injured by the fire and thanked emergency services “for their swift action”.
“Our teams are currently mobilising temporary equipment to site however we are unable to provide specific timelines for restoration of any services,” a spokesperson said.
The 315m (1,032ft) tall tower was built in 1969 and provides coverage for homes across northern England, from Tadcaster to Seaham.
The services affected include:
- Channels on the PSB1, 2, 3, COM4, 5, 6, 7 and LTV television multiplexes
- BBC Radio Tees, BBC Radios 1-4 and BBC DAB
- Commercial radio stations SDL, North Yorkshire DAB, BAUER Teesside, Digital 1, TFM, Capital, Heart and Classic FM
Sky, Freesat and cable services are not affected.
Coverage of BBC Radio Tees on DAB is reduced but some reception should continue for most listeners and there is no need to re-tune. You can also listen live here.
Listeners to the BBC’s national radio services on FM should attempt to re-tune to a neighbouring transmitter, ensuring aerials are fully extended and placed near windows.
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