47 CFR § 73.1201 - Station identification.
(a) When regularly required. Broadcast station identification announcements shall be made:
(1) At the beginning and ending of each time of operation, and
(2) Hourly, as close to the hour as feasible, at a natural break in program offerings. Television and Class A television broadcast stations may make these announcements visually or aurally.
(b) Content.
(1) Official station identification shall consist of the station's call letters immediately followed by the community or communities specified in its license as the station's location; Provided, That the name of the licensee, the station's frequency, the station's channel number, as stated on the station's license, and/or the station's network affiliation may be inserted between the call letters and station location. TV stations, or DAB Stations, choosing to include the station's channel number in the station identification must use the station's major channel number and may distinguish multicast program streams. For example, a TV station with major channel number 26 may use 26.1 to identify an HDTV program service and 26.2 to identify an SDTV program service. A TV station that is devoting one of its multicast streams to transmit the programming of another television licensee must identify itself and may also identify the licensee that it is transmitting. If a TV station in this situation chooses to identify the station that is the source of the programming it is transmitting, it must use the following format: Station WYYY, community of license (call sign and community of license of the station whose multicast stream is transmitting the programming), bringing you WXXX, community of license (call sign and community of license of the licensee providing the programming). The transmitting station may insert between its call letters and its community of license the following information: the frequency of the transmitting station, the channel number of the transmitting station, the name of the licensee of the transmitting station and the licensee providing the programming, and/or the name of the network of either station. Where a multicast station is carrying the programming of another station and is identifying that station as the source of the programming, using the format described above, the identification may not include the frequency or channel number of the program source. A radio station operating in DAB hybrid mode or extended hybrid mode shall identify its digital signal, including any free multicast audio programming streams, in a manner that appropriately alerts its audience to the fact that it is listening to a digital audio broadcast. No other insertion between the station's call letters and the community or communities specified in its license is permissible.
(2) A station may include in its official station identification the name of any additional community or communities, but the community to which the station is licensed must be named first.
(c) Channel—(1) General. Except as otherwise provided in this paragraph, in making the identification announcement the call letters shall be given only on the channel, or channels in the case of a broadcaster that is multicasting more than a single channel, identified thereby.
(2) Simultaneous AM (535-1605 kHz) and AM (1605-1705 kHz broadcasts. If the same licensee operates an AM broadcast station in the 535-1605 kHz band and an AM broadcast station in the 1605-1705 kHz band with both stations licensed to the same community and simultaneously broadcasts the same programs over the facilities of both such stations, station identification announcements may be made jointly for both stations for periods of such simultaneous operations.
(3) Satellite operation. When programming of a broadcast station is rebroadcast simultaneously over the facilities of a satellite station, the originating station may make identification announcements for the satellite station for periods of such simultaneous operation.
(i) In the case of a television broadcast station, such announcements, in addition to the information required by paragraph (b)(1) of this section, shall include the number of the channel on which each station is operating.
(ii) In the case of aural broadcast stations, such announcements, in addition to the information required by paragraph (b)(1) of this section, shall include the frequency on which each station is operating.
(d) [Reserved]
(e) Transport Stream ID (TSID) values are identification numbers assigned to stations by the FCC and stored in the Commission's online database. Two sequential values are assigned to each station.
(1) All TV and Class A TV stations shall transmit their assigned odd-numbered TSID.
(2) In ATSC 3.0, a similar value is used called a Bit Stream ID (BSID). Stations operating in ATSC 3.0 mode shall utilize their assigned even-numbered TSID as their BSID, consistent with paragraph (e)(1) of this section.