Text telephone (TTY).

Text telephone (TTY). A machine that employs graphic communication in the transmission of coded signals through a wire or radio communication system. TTY supersedes the term TDD or telecommunications device for the deaf, and TT.

Source

47 CFR § 9.3

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Scoping language

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.

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