AASTRA DT4x2 for MX-ONE User Guide EN - Manual (Page 107)

107 DT412/DT422/DT432
Settings
Set the clock manually
When you have entered Settings: г б
Select General. ã
Select Clock. á
Press. â
or
ã
Select Manual setting.
Select
Press (see display). å
Enter time, year, month, and day according to the example
below.
Example: Time:0815, Year:2002, Month:03, Day:30.
Save
Press (see display).
The setting is saved.
Set the clock to be visible/invisible in idle mode
When you have entered Settings: г б
Select General. ã
Select Clock.
Change
Press (see display).
The clock checkbox is marked/unmarked.