Common carrier or carrier. Any common carrier engaged in interstate Communication by wire or radio as defined in section 3 of the Communications Act of 1934, as amended (the Act), and any common carrier engaged in intrastate communication by wire or radio, notwithstanding sections 2(b) and 221(b) of the Act. Communications assistant (CA). A person who transliterates or interprets conversation between two or more end users of TRS.
47 CFR § 9.3
Terms with definitions including the (RR) designation are defined in the same way in 2.1 of this chapter and in the Radio Regulations of the International Telecommunication Union.