Ian Forman, 42, developed a homemade bomb and researched religious venues in Merseyside, Kingston Crown Court heard.
Forman, of Shavington Avenue, Oxton, Birkenhead, was detained after work colleagues found him researching chemicals and explosives on the web.
The explosive was discovered during a police raid, along with a replica Nazi uniform and bomb plans.
Officers said seized computers showed evidence of internet research into a number of mosques in Merseyside, including Penny Lane Mosque, Liverpool and Wirral Cultural Centre, Birkenhead.
http://www.bbc.co.uk/news/uk-england-merseyside-27237768