Ultratec 4425 - Manual (Page 96)

Conversation Etiquette
GA When you talk with another person by TTY, you
type while the other person reads. When you want
the other person to respond, type GA for “Go
ahead.”
GA OR SK To say goodbye, type GA OR SK. This gives the other
person a chance to say any last words before ending
the conversation.
SKSK Type SKSK to end the conversation.
Q Some people prefer to type Q instead of a question
mark because it saves time and is easier to type.
You can use punctuation marks such as commas and periods,
although many people choose to omit them. You may also
abbreviate words,
such as:
GA go ahead OPR operator
SK stop keying PLS please
CD could Q question mark
CUL see you later R are
CUZ because SHD should
HD hold THX thanks
MTG meeting TMW tomorrow
NBR number U you
OIC oh, I see UR your