Samsung GALAXY CORE Prime User Manual page 117

Setting
US dialing
International dialing
TTY mode
Hearing aids
DTMF tones
Voice privacy
Use the Call Settings Menu
1. From home, tap Phone
The phone app opens.
2. Tap More options > Settings > Call.
Phone App
Replace + with the international dialing code, except when entering
+1.
Enter the international dialing code automatically.
Enable service on your phone.
Improve the sound quality of your phone when using hearing aids.
Set the length of DTMF tones, which are used when pressing the
keypad while on a call.
Activate Enhanced privacy mode.
.
Description
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