... Product Description solar radioProduct function:1. Crank by hand for power generation2. Solar energy for power generation3. FM / AM / WB radio functionUse ... handle, hold the unit and crank the handle byanother hand at the speed of 2 to 3 circles per ... switch clockwise, a crack sound will heard to show power on, then turn to make a clangorous sound. 2 ... , a crack sound will heard to show power off