Why is a non-acoustic connection point needed for TTYs?
Traditionally, people with communication disabilities used a TTY by placing a telephone handset in an acoustic modem on top of the TTY. Some manufacturers reduced the size of their TTY by removing the acoustic modem, thus requiring the TTY to connect directly to a telephone or wall jack. Therefore, if a new phone system has hardwired cords with no port for direct connection, then a direct connect TTY cannot be used at that phone and the phone will be considered non-conforming with this section 508 provision. Why must phone systems be capable of intermixing speech and TTY tones and why must users be able to turn microphones on and off? This provision supports VCO and HCO. People with communication disabilities have reported instances in which they connected a TTY to a cellular phone, which resulted in a deactivation of the telephone s microphone. In those cases, there was no way to talk into the phone (no way to turn the microphone on). This is frustrating to people with a hearing disab
