He said only an injection of outside influence could make the broadcaster "relevant to the internet age" and admitted that he did not presently pay for it via the licence fee.
In an interview with BBC2's Newsnight, he insisted his idea was serious and backed by a group of "like-minded people who don't want to see Britain lose the BBC".
Nicknamed 'Project Reith' - after the Corporation's first director - it had "run some models" of possible present and future values, he said, though he had "absolutely no idea" what the price might be.
"We believe that the BBC is sleepwalking itself to destruction and the BBC will be lost to Britain and we do not think that is right," he said.
"This is a really serious situation where the BBC, because of its triple problems of the way in which it's been funded, historic baggage and the way in which it is used as a political football, its very future is in doubt."
"It's a patient that is now terminally ill and it needs another force from outside to cure it and make it fit for a world that we couldn't have envisaged 10 years ago."
He declined to disclose how the schedules might look if he got his way - but pointed to the sums presently spent on the World Service and Welsh-language programming.
"Because of the historic baggage we've got a ridiculous situation where the licence fee now covers the World Service," he said.
"Most people in Britain don't even know how to get the World Service.
"There are 50,000 people speaking Gaelic. Welsh language has been declining over 10 years and the BBC spends £48 million on that."
Asked if he paid the licence fee, he said: "I don't have a TV licence. I don't watch except on catch-up."