VIETA CDV7500GP Owner's Manual page 53

System Setting Operation
Tap
12 Hour Mode
Calibration
Tap
the Calibration setting.
When the target moves to another position, tap and hold at the
center of the new target. Repeat each time to complete the
calibration process.
Once completed, tap anywhere on screen to go back to menu
screen.
Note:
This Calibration is for the display touch screen. If found the
touch screen buttons sensitive became low, the re-calibration is
necessary.
bar to change time format to 24 hours.
bar on the Display Setting menu screen to start
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