Select > Settings and Phone > Network .
To select the network mode, select Network mode and Dual mode, UMTS, or GSM. In dual mode, the device switches automatically between networks.
Selecting UMTS enables faster data transfer, but may increase the demand on battery power and reduce the battery life. In regions close to both GSM and UMTS networks, selecting Dual mode may cause constant jumping between the two networks, which also increases the demand on battery power.
To select the operator, select Operator selection and Manual to select from available networks, or Automatic to set the device to select the network automatically.
To set the device to indicate when it is used in a microcellular network (MCN), select Cell info display > On .