Sony alpha 330 Instruction Manual page 127

When the LIVE VIEW/OVF switch is set to "OVF," looking into the
viewfinder turns off the LCD monitor.
In the default setting, while looking into the viewfinder, the LCD monitor
is turned off to prevent the battery pack from wearing down.
If you want to turn on the LCD monitor while looking into the viewfinder,
select [Off].
MENUbutton -+ _ 1 -+ [Autooffw/VF] -+ [Off]
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