Final answer:
TTY equipment is needed for making phone calls.
Step-by-step explanation:
To communicate by TTY, TTY equipment is needed for making phone calls. TTY, which stands for Text Telephone, is a device used to facilitate communication for individuals with hearing or speech impairments. It allows users to type messages on a keyboard, which are then transmitted as text to another TTY device. The recipient can read the message on their own TTY device or respond using the same method.