Hearing Carry Over (HCO) allows a hearing person with a speech disability to listen to the person they are calling. The HCO user types his/her conversation for the operator to voice to their caller.
HCO to TTY
HCO users can contact other TTY users but have the choice to listen to what the TTY users are saying back to them. HCO users can listen while the relay operator is voicing the typed message from the TTY user. The HCO user will then type their conversation directly to the TTY user.
HCO to HCO
Two HCO users can contact each other through relay. The relay operator will voice what both users type, one person at a time. When one user says "GA", it will be the other person's turn to speak.