Low Head, Tasmania possesses the only working Type G diaphone (one of the largest models constructed) in the world. It has an audible range of up to 20 miles. Lindesnes Lighthouse in southern Norway. The last Sunday of July, Fog Horn Day is held at the lighthouse. External links Animation of the operation of the Hope-Jones diaphone: Gamewell Diaphone Photographs of diaphone foghorn components: Douglas Head lighthouse, Isle of Man Horn & Whistle Board: Diaphone foghorn References Canadian inventions Navigation