Amateur radio requires the call sign to be stated at the end of a communication and every ten minutes during (some hams use countdown clocks to remind them to identify); modes such as packet radio and fast-scan television often have a provision for automatic identification, either including it as part of a digital data stream or overlaying it over an analog picture. Repeaters are often designed to automatically transmit the repeater's callsign, usually in Morse code. The requirements for the United States are covered in Title 47 of the Code of Federal Regulations, part 97.119.
