Need to know what a TTY is?
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What exactly is a TTY, TDD and/or Text Telephone?... is there a difference?
With all the acronyms and other confusing lingo, people find
it hard to understand what a TTY or TDD or text telephone is and what
it actually does. Of course, nobody is going to buy something they don't
understand, so let us explain. All these different names mean the same
thing: TTY stands for teletypewriter, TDD stands for Telecommunication
Devices for the Deaf and Text telephone means a phone that is enabled
to send text over phone lines. All these terms are referring to the
So how does a TTY / TDD / Text Telphone work?
This device or phone, when hooked up to a phone or analog
jack, allows for the typing of messages back and forth between text
telephones. Anybody can call in to a TTY phone (presumably to a hard
of hearing or deaf person) from a relay service, also known as Telecommunications
Relay Service or TRS (people love making up acronyms). Under Title IV
of the Americans with Disabilities Act, this service must be offered
free of charge by every state (just press 7-1-1 to get into touch with
a representative from your state relay center).
What is VCO?
The Text telephone user can call in to the relay service and give the
service representative a phone number to call to facilitate the relay.
The TTY user can type in the message which the relay rep will verbally
relay to the other person. The other person will verbally speak his
message and the relay representative will type it into the Text telephone.
Also, a non-TTY user can facilitate a call to the relay service (also
by calling 7-1-1) so he or she can communicate with a TTY user. This
service is available 24 hours a day.
Some Text Telephones offer VCO (yet another acronym) which
stands for Voice carry over. This feature allows people who are hard
of hearing but not speaking to communicate verbally but get typed communication
relayed from the relay representative to the TTY phone.
What is HCO?
Some text telephones offer HCO (another one?) which stands
for hearing carry over. This feature allows people who hear clearly
but have difficulty speaking on the phone to communicate through the
relay representative by typing and listening to the other person regularly.
So the relay representative will verbally relay your typed message while
you listen to the personís responses directly.
Federal law believes people with these types of disabilities deserve to
communicate as effectively as everyone else, so we hope this information
will help people understand and use these helpful services.
Click here or more information about Relay Services
Contact the FCC directly
Click here to buy a TTY Phone
Some other common questions:
Is my cellular or cordless phone TTY compatible?
Please contact the manufacturer of the product you are
looking to purchase to make absolutely sure your cellular or cordless
phone is compatible with product your interested in:
Can my computer communicate with a TTY directly?
Krown Manufacturing, Inc.
12082 Western Avenue
Garden Grove, CA 92841-2913
(800) 874-3005 voice
(800) 772-2889 TTY
(714) 897-4703 fax
3408 Indale Road
Fort Worth, TX 76116
(817) 738-2485 voice
(817) 738-8993 TTY
(817) 738-1970 fax
Text telephone communication is done through a different
type of Data transmission code than regular computers called Baudot,
which is incompatible with ASCII (American Standard Code for Information
Interchange), which is the worldwide computer standard code. A Baudot/ASCII
modem, or TTY modem, is necessary to make your computer act like a
TTY. This 300 baud modem is more expensive than regular data modems
and canít be used as a replacement for a data modem. You must have
two modems for separate computer activities (if there is a modem out
there that does both, please let us know).
Below is the most promising hardware and software provider we can
find for this need: