47 CFR § 74.882 - Station identification.
(a) For transmitters used for voice transmissions and having a transmitter output power exceeding 50 mW, an announcement shall be made at the beginning and end of each period of operation at a single location, over the transmitting unit being operated, identifying the transmitting unit's call sign or designator, its location, and the call sign of the broadcasting station or name of the licensee with which it is being used. A period of operation may consist of a continuous transmission or intermittent transmissions pertaining to a single event.
(b) Each wireless video assist device, when transmitting, must transmit station identification at the beginning and end of each period of operation. Identification may be made by transmitting the station call sign by visual or aural means or by automatic transmission in international Morse telegraphy.
(1) A period of operation is defined as a single uninterrupted transmission or a series of intermittent transmissions from a single location.
(2) Station identification shall be performed in a manner conducive to prompt association of the signal source with the responsible licensee. In exercising the discretion provide by this rule, licensees are expected too act in a responsible manner to assure that result.