The time calculated by atomic clocks is sent to radio towers.In Germany, the tower is located in Mainflingen near Frankfurt. In Great Britain, the tower can be found in Anthorn. In the USA, the tower is located in Fort Collins. The tower in Japan can be found in Fukushima in the North East and Fukuoka in the South West. The tower for China is located in Shangqiu. The radio tower in Mainflingen reaches a watch with radio technology within a radius of up to 1,500 km depending on the model.