A telecommunications device for the deaf is a specialized terminal equipped with a keyboard and a display screen, allowing users with hearing or speech impairments to communicate over standard analog telephone networks. The device converts keystrokes into audio tones that are transmitted across the PSTN and decoded by a compatible device at the receiving end.
The customer requires a TDD relay service to complete the setup process over the phone.
Also heard as
- TTY
- text telephone
Related terms
PSTN
The global infrastructure of circuit-switched telephone networks operated by national and regional carriers.
Relay
A telecommunications service that facilitates calls between users with hearing or speech disabilities and users of standard telephones.
Acoustic coupler
An early modem interface that connected a computer to a telephone network by physically cradling a telephone handset.