Following an experiment by the former UK broadcast regulator Radio Authority, since 2005 some 200 such stations have been licensed by broadcasting regulator Ofcom. Most community radio stations in the UK are on FM, typically at a power of 25 watts. FM community radio stations include Andover Radio, Cambridge 105, Chiltern Voice FM, Preston FM and Penistone FM. A few community radio station also operate on AM (medium wave), particularly in rural areas, and some community radio stations operate online, like Windmill Broadcasting, the UK's only radio station broadcasting from a Windmill, in the Broad Eye Windmill, Stafford.