A man who wrote a terrorists' handbook using information from an al-Qaeda training manual has pleaded guilty to offences under the Terrorism Act.
Terrance Brown, 46, from Portsmouth, compiled CDs which included instructions about how to build bombs.
The discs, called the Anarchist's Cookbook, were sold for $35 (£23).
Brown pleaded guilty to seven counts of collecting information that could have been used to prepare or commit acts of terrorism at Winchester Crown Court.
The maximum sentence is 10 years. He will be sentenced on 2 June.
Two additional counts of recklessly disseminating the information and one count of transferring criminal property will lie on file.
The discs were sold worldwide on a website, which is now closed, between 2003 and 2008 from his home in Whitworth Road.
They included, among other things, extracts from the Mujahideen Poisons Book and instructions on how to build improvised explosive devices.
The court was told that Brown made tens of thousands of pounds from the business but had no terrorist sympathies.
He is now penniless and has county court judgements against him, the court heard.
Parmjit Cheema, prosecuting, told the court that the haul of terrorist information was the largest ever found in the UK.
The judge, Sir Geoffrey Grigson, granted Brown bail and adjourned the case for reports.