Optoma Ep728i Projector User Manual

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Appendices
Image Problems
 No image appears on-screen
 Ensure all the cables and power connections are correctly and 
securely connected as described in the “Installation” section.
 Ensure all the pins of connectors are not bent or broken.
 Check if the projection lamp has been securely installed. Please 
refer to the “Replacing the lamp” section.
 Make sure you have removed the lens cap and the projector is 
switched on.
 Partial, scrolling or incorrectly displayed image
 Press...

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 6.  Select the “Change” button under the “Monitor” tab.
  7.  Click on “Show all devices”. Next, select “Standard monitor 
types” under the SP box; choose the resolution mode you need 
under the “Models” box. 
  8.  Verify that the resolution setting of the monitor display is 
lower than or equal to UXGA (1600 x 1200). 
 If you are using a Notebook:
  1.  First, follow the steps above to adjust resolution of the 
 
computer.
  2.  Press the toggle output settings. Example:...

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 Image is out of focus
 Make sure the lens cap is removed.
 Adjusts the Focus Ring on the projector lens. 
 Make sure the projection screen is between the required distance 
3.9 to 39.4 feet (1.2 to 12.0 meters) from the projector.  
See page 17.
 The image is stretched when displaying 16:9 DVD title
When you play anamorphic DVD or 16:9 DVD, the projector will 
show the best image in 16:9 format on projector side.
If you play 4:3 format DVD title, please change the format as...

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Appendices

Intermission Problems
 The projector stops responding to all controls
 If possible, turn off the projector, then unplug the power cord and 
wait at least 60 seconds before reconnecting power.
 Lamp burns out or makes a popping sound
 When the lamp reaches its end of life, it will burn out and may  
make a loud popping sound. If this happens, the projector will not 
turn on until the lamp module has been replaced. To replace the 
lamp, follow the procedures in the “Replacing the...

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 Message Reminders
 
 Fan failed:
 
 Temperature warning:
 
 Replacing the lamp:
 
 Out of range: (refer to page 49)
  
  

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Remote Control Problems
 If the remote control does not work
 Check the operating angle for the remote control is approximately 
±22.5°.
 Make sure there are no obstructions between the remote  
control and the projector. Move to within 6 m (20 ft) of the  
projector.
 Make sure the batteries are inserted correctly.
 Replace weak batteries in the remote control. 

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Replacing the lamp
The projector automatically detects the lamp life. When the 
lamp life is nearing the end of use, you will receive a warning 
message.
 
When you see this message, please contact your local reseller 
or service center to change the lamp as soon as possible. Make 
sure the projector has been cooled down for at least 30 min-
utes before changing the lamp. 
 Warning: Lamp compartment may be hot! Allow it to cool 
down before changing the lamp!
 Warning: To reduce...

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Lamp Replacement Procedure:
1.  Switch off the power to the projector by pressing the “Power” button.
2.  Allow the projector to cool down for at least 30 minutes.
3.  Disconnect the power cord.
4.  Use a screwdriver to unscrew the 2 screws from the cover. 
5.  Push up and remove the cover. 
6.  Use a screwdriver to unscrew the 2 screws from the lamp module. 
7.  Pull up the lamp handle carefully. 
8.  Remove the lamp module. 
To replace the lamp module, reverse the previous...

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Compatibility Modes
ModeResolutionV-Sync (Hz) 
AnalogDigital
VGA640 x 48060, 72, 75, 8560, 72, 75, 85
VGA720 x 40070, 8570, 85
SVGA800 x 60056, 60, 72, 75, 8556, 60, 72, 75, 85
SVGA832 x 6247272
XGA1024 x 76860, 70, 75, 8560, 70, 75, 85
XGA1152 x 86460, 70, 75, 8560, 70, 75, 85
WXGA1280 x 72050, 60***
WXGA1280 x 7686060
WXGA1280 x 8006060
SXGA1280 x 102460, 75, 8560, 75, 85 (85Hz,  Sub-sampling mode)
SXGA+1400 x 10506060 (Sub-sampling mode)
UXGA1600 x 12006060 (Sub-sampling mode)...

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RS232 Commands
Pin no.NameI/O (From Projec-tor Side
1TXDOUT
2RXDIN
3GND__
Pin no.Spec.
1N/A
2RXD
3TXD
4DRT
5GND
6DSR
7RTS
8CTS
9N/A
12345
6789
12
3
RS232 ConnectorVGA-In Connector