Zte Z963VL User Manual page 73

TTY HCO: Users who can hear, but cannot talk, may use

this mode to listen to conversation of the other party, and
respond via text messages.
TTY VCO: Users who can talk, but cannot hear, may use

this mode to talk through the phone and receive
responses via text messages.
Set Hearing Aids
Your phone supports HAC (Hearing Aid Compatibility) function.
When you turn on the hearing aid compatibility and use a hearing
aid with a Telecoil to answer the phone, it will help you hear more
clearly during the phone call.
1. Touch the Home key >
Settings > Call settings.
2. Check Hearing aids to turn on hearing aid compatibility.
> (in the top search field) >
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