Samsung A820 Manual page 86

To place roaming calls with Call Guard on:
1.
From standby mode, dial 1 + area code + the seven-digit
number and press
2.
Press
To answer incoming roaming calls with Call Guard on:
1.
Press
2.
Press
Reminder:
78
to confirm Roaming Rate.
to confirm Roaming Rate.
If the Call Guard feature is set to On , you need to take
extra steps to make and receive roaming calls.
Section 2D: Controlling Your Roaming Experience
.