Tadiran Telecom EMERALD ICE Quick Start Manual page 14

You can select [YES] to register, or [NO] to exit this mode.
Press [F3] (the same as [OK] key) to confirm, the LCD will
display: (e.g. [YES])
4. Move the handset near the base. The system will start to
register with the base unit. If the registration operation is
successful, the LCD will display:
Note:
1. There are 2 EKT lines from KSU to the base.
2. If the handset ID is #1 means the handset is connect to
the Line#1. If the handset ID is #2 means the handset is
connect to the Line#2.
5. If the registration function fails, the LCD will display:
System Registration
Page 2-3