What is a TTY?

A TTY is also known as a TDD (Telecommunications Device for the Deaf)

HOW IT WORKS: This device 'rings' via flashing light or the more recent vibrating wrist band that resembles a watch. The TTY consists of a keyboard, which hold somewhere from 20 to 30 character keys, a display screen, and a modem. The letters that the TTY usre types into the machine are turned into electrical signals that can travel over regular telephone lines. When the signals reach their destination (in this case another TTY) they are converted back into letters which appear on a display screen, are printed out on paper or both. Some of the newer TTYs are even equipped with answering machines.

WHO USES IT: The TTY has 4 million users nationwide. 3 million of tese users are hearing impaired and the other 1 million have severe speech impairments.

ADVANTAGES: Without a means of Telecommunication, the deaf were, in a sense, isolated from many people and services. Life without a telephone substitute involved many miles of driving to deliver and relay messages. (Which was very time consuming and frustrating.) The TTY gives deaf people the luxury of just being able to pick up the phone and chat. It also provided an easier way to connect to police and fire stations in case of emergency. And with the later creation of MRCs (message relay centers) the TTY users could connect to any phone anywhere in the world.

DISADVANTAGES: TTY users must know how to type. The alarmingly high spelling error rate of 5-6% (10% of which is TTY machine realted as in the misfunction of a key) sometimes causes a problem in communication. One half million of TTY users communicate using ASL (American Sign Language) or which there is no written counterpart. ASL also has a grammatical system which differs greatly from that of Standard English. If a TTY user is especially "chatty", the other party must just sit quietly until the "chatty" person sends the message, which they must then read and respond to. A conversation such as this would end up taking much longer than the avrage phone call.


COST: $300-$600 depending on what type of model you purcahse. (source: Communications of the ACM May 1992 v35 n5 p80)TTYs (TDD) can be rented from US West for five dollars a month.

MRC (Message Relay Centers) Minnesota

HOW THEY WORK: A hearing caller who needs to get in touch with a TTY user yet does not possess a TTY of his own can use a MRC to make his call. The caller simply calls MRC (1-800-627-3529 - TTY or voice). The operator at the center will use a TTY to call the party that the hearing person is trying to reach. The operator acts as an interpeter, typing the heaing person's message into a TTY and reading the response to him as it returns. (This works vice versa for a deaf caller trying to reach a hearing party.)

ADVANTAGES: The deaf can connect to any phone anywhere at any time. Their communicatiuon is no longer limited to other TTY users. It opened up many services including mail order catalogs.

COST: free (same cost as call would have cost to dial direct) +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ + This is part of a series of references generated by students + + at Michigan State University to be placed into Deaf Gopher. + + This was a part of CEP 341 American Sign Language & the Deaf + + Community in the spring of 1993 + +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

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