Samsung SPHA820 Phone Manual page 160

The status of a Sprint PCS Ready Link call is displayed as
follows:
The Green LED On indicates you have the floor and
may speak.
The Red LED On indicates another contact has the floor.
The LED Off indicates the floor is open. (You can take the
floor and speak by pressing and holding
152
Main LCD Display during a Ready Link Call
Section 2J: Using Sprint PCS Ready Link
.)