Sony ILCA-77M2Q - Manual (Page 54)

Setting the date and time
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The date and time setup screen appears automatically when the power is
turned on for the first time or when the internal rechargeable backup battery
has been discharged. To reset the date and time, use the menu.
Maintaining the date and time setting
This camera has an internal rechargeable battery for maintaining the date
and time and other settings regardless of whether the power is on or off, or
the battery is installed or not.
Setting the date/time and area again
MENU button t (Setup) 4 t
[Date/Time Setup] or [Area Setting]
(page 43)
MENU button