Kyocera 2100 Series - Manual (Page 26)

6 Getting Started
Screen icons
The following icons may appear on your phone screen:
The phone is operating in CDMA digital mode. If does not
appear, the phone is operating in analog mode (2135 only).
The phone is receiving a signal. You can make and receive calls.
The phone is not receiving a signal. You cannot make or receive
calls.
A call is in progress.
The alarm clock is set.
The phone vibrates or lights up instead of ringing.
The phone is roaming outside of its home service area.