teletypewriter(English)

• in the 1960s with the invention of the acoustic coupler (which holds the telephone handset receiver) and teletype machines, deaf and hard of hearing people were able to call each other directly using these devices. In the late 1970’s and through the 1980’s, much smaller and compact versions of the TTY were manufactured, and made available through state TTY equipment distribution programs
• NAD
• Auditory system, Disability
• https://www.nad…relay-services/