HP iPAQ Glisten-AT&T - Manual (Page 149)

30 Accessibility
Turn on TTY Mode
▲ Press Start , tap Settings > Personal > Phone > HAC/TTY tab, and then tap TTY Mode.
Turn on T-Coil mode (Hearing Aid Compliant)
If you are using a hearing aid with a telecoil, you can turn on T-Coil mode to reduce interference
between your hearing aid and iPAQ.
▲ Press Start , tap Settings > Personal > Phone > HAC/TTY tab, and then tap HAC Mode.
Turn on TTY Mode 137