Sony Ericsson Dialog 4223 - Manual (Page 17)

17 BusinessPhone – Dialog 4223 Professional / Dialog 3213
Description
Signals
Ringing signals are emitted from the phone.
Note: The tones and ringing signals in this guide refer to the
standard system but may vary between countries.
Internal ringing signal - repeated after 4 s
External ringing signal - repeated after 4 s
Automatic Callback signal