TTY Devices:Roaming Phones for

the Disabled

By: Latia Hill

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Benefits & How it Helps

• TTY technology gives the deaf and hard of TTY technology gives the deaf and hard of hearing a text-based system for communicating hearing a text-based system for communicating over phone lines among themselves or with over phone lines among themselves or with hearing individuals. hearing individuals.

• A.A. With just TTY units and the With just TTY units and the phone system, people who are hard of phone system, people who are hard of hearing can communicate with each other. hearing can communicate with each other.

• IIf electrical power is out in your area, you f electrical power is out in your area, you can still send and receive messages with can still send and receive messages with your TTY unit.your TTY unit.

Drawbacks

• The vocoder found in most cell phones -- the device that turns speech into digital format for transmission -- can't send a message without tiny glitches of dropout

• For voice communications, the glitches are often imperceptible, but for TTY machines, a tiny disturbance can garble an entire message.

Limitations

•A. They will also need a cellular telephone with the TTY chipset installed, but exactly who will manufacture the phones is uncertain.

• While the technology to transmit TTY communications via digital phone increases mobility, users will still be limited to the 30 words per minute speed of the TTY.

http://www.wired.com/science/discoveries/news/2000/01/33945