Samsung Galaxy S4 User Manual page 336

Network Operators
Using this feature you can view the current network connection. You
can also scan and select a network operator manually, or set the
network selection to Automatic.
1. From the main Settings page, tap Connections tab
networks
2. Tap Network operators. The current network connection
displays at the bottom of the list.
Important! You must deactivate data service prior to searching for an
available network.
3. Tap Search now to manually search for a network.
4. Tap Select automatically to automatically select a network
connection.
Note: Connecting to 2G networks slows the data transfer speed and
time.
328
Mobile networks.
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