Acer PD726 - Manual (Page 17)

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Installation
Adjusting the Projector Image Height
The projector is equipped with elevator feet for adjusting
the image height.
To raise the image:
1. Press the elevator button  .
2. Raise the image to the desired height angle 
, then
release the button to lock the elevator feet into position.
3. Use  to fine-tune the display angle.
To lower the image:
1. Press the elevator button.
2. Lower the image, then release the button to lock the
elevator feet into position.
3. Use  to fine-tune the display angle.
Elevator Foot
2
1
Tilt Adjusting Wheel 3
Adjusting the Projected Image
Elevator Button