47 C.F.R. § 74.791

(a) New low power and television translator stations. Call signs for new TV translator and LPTV stations will be made up of a prefix consisting of the initial letter K or W followed by the channel number assigned to the station and two additional letters and a suffix consisting of the letters -D, consistent with paragraph (d) of this section. Prior to filing a license to cover, a new LPTV station must modify its call sign to be consistent with the requirements of paragraph (c) of this section.

(b) Television translator stations. Call signs for TV translator stations will be made up of a prefix consisting of the initial letter K or W followed by the channel number assigned to the station and two additional letters and a suffix consisting of the letter -D, consistent with paragraph (d) of this section.

(c) Low power television stations and Class A television stations. (1) Call signs for LPTV and Class A television stations will be made up of a four-letter prefix pursuant to § 73.3550 of this chapter along with a two-letter suffix. LPTV stations will be assigned the suffix -LD and Class A stations will be assigned the suffix -CD.

(2) An LPTV or Class A station that is licensed as of December 19, 2025, may retain its call sign as of that date and is not required to comply with the requirements of paragraph (c) unless it changes its service designation (voluntarily or involuntarily) or chooses to modify its call sign.

(d) Call sign protocol. The use of the initial letter generally will follow the pattern used in the broadcast service, i.e., stations west of the Mississippi River will be assigned an initial letter K and those east, the letter W. The two letter combinations following the channel number will be assigned in order, and requests for the assignment of the particular combinations of letters will not be considered. The channel number designator for Channels 2 through 9 will be incorporated in the call sign as a 2-digit number, i.e., 02, 03, etc., so as to avoid similarities with call signs assigned to amateur radio stations. In the event that the two letter combination following the channel numbers reaches ZZ, the next subsequent call sign shall have three letters, beginning with AAA.