A TTY lets the 30 million Americans who are deaf, hard of hearing, or speech-impaired use the telephone to communicate by typing messages back and forth to one another on a keyboard attacked to the phone. Since both parties require a TTY when communicating, it doesn't bridge the gap between the deaf world and the hearing world, where few people have TTYs on their phones. Fortunately, today, lots of other products are bridging that gap. As microelectronics and computers have gotten smaller and cheaper to make, the number of useful products for the deaf and hearing-disabled has multiplied. With today's tech, my grandfather would have been considerably less frustrated.
Users can strap the attachment onto the ear-piece of a telephone handset.
A dial on the magnifier controls volume. For the hard of hearing, these magnifiers can enable nearly normal telephone conversations. This product is portable and can be used anywhere. Keel also uses a TTY machine with an integrated answering machine. The machine responds to incoming calls with both a voice and a TTY greeting.