Optoma Gt720 Projector User Manual

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Appendices
 Image is out of focus
 
Make sure the lens cap is removed.
 Adjust the Focus Ring on the projector lens. 
 Make sure the projection screen is between the required distance. 
See page 16.
  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 when the projector display mode is set to 
16:9 in the OSD.
 If you play 4:3 format DVD titles, please change the format to 4:3 
in the projector OSD.
 If...

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Appendices
  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.
  Check that “Keypad Lock” is not activated by trying to control the 
projector with the remote control.
  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...

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Appendices
 On Screen Messages 
 Temperature warning:
 
 Fan failed:
 
 Lamp warming:
 
 Out of display range:
 
  If the remote control does not work
 
Check the operating angle of the remote control is within ±15° 
both horizontally and vertically of one of the IR receivers on the 
projector.
 Make sure there are not any obstructions between the remote 
control and the projector. Move to within 7 m (±0°) of the projector.
 Make sure the batteries are inserted correctly.
 Replace...

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Appendices
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 l east 30 
minutes before changing the lamp. 
 Warning: Lamp compartment may be hot! Allow it to cool  down before changing the lamp!
 Warning: To reduce the...

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Appendices
Lamp Replacement Procedure:
1. Switch off the power to the projector by pressing the “” button. 
2.  Allow the projector to cool down for at least 30 minutes.
3.  Disconnect the power cord.
4.  Unscrew the two screws on the cover. 
1
5.  Lift up and remove the cover. 
2
6.  Unscrew the two screws on the lamp module. 
3
7.  Lift up the lamp handle and remove the lamp module slowly and carefully . 
4
To replace the lamp module, reverse the previous steps.
8.   Turn on the projector and...

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Appendices
Compatibility Modes
Mode Resolution V-Sync (Hz)
H-Sync (KHz)
Anglog DigitalAnglog Digital
VGA 640 × 350 707031.50 31.50
VGA 640 × 350 858537.90 37.90
VGA 640 × 400 858537.90 37.90
VGA 640 × 480 606031.50 31.50
VGA 640 × 480 6767 --
VGA 640 × 480 727237.90 37.90
VGA 640 × 480 757537.50 37.50
VGA 720 × 400 707031.50 31.50
VGA 720 × 400 858537.90 37.90
SVGA 800 × 600 565635.20 35.20
SVGA 800 × 600 606037.90 37.90
SVGA 800 × 600 727248.10 48.10
SVGA 800 × 600 757546.90 46.90
SVGA 800 ×...

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Video Compatibility Computer Compatibility
Mode Resolution V-Sync (Hz) H-Sync (KHz)
MAC LC 13” 640 × 480 66.66 34.98
MAC II 13” 640 × 480 66.68 35.00
MAC 16” 832 × 624 74.55 49.73
MAC 19” 1024 × 768 7560.24
MAC 1152 × 870 75.06 68.68
MAC G4 640 × 480 6031.35
i MAC DV 1024 × 768 7560.00
i MAC DV 1152 × 870 7568.49
NTSCM (3.58MHz), 4.43 MHz
PAL B, D, G, H, I, M, N
SECAM B, D, G, K, K1, L
SDTV/HDTV 480i/p, 576i/p, 720p@50Hz/60Hz, 1080i/p@50Hz/60Hz
 
  

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Appendices
RS232 Pin Assignments
Pin no. Spec.  
(from projector side)
1 N/A
2 RXD
3 TXD
4 N/A
5 GND
6 N/A
7 N/A
8 N/A
9 N/A
1
2
3
4
5
6
7
8
9
RS232 Commands and Protocol 
Function List   

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RS232 Protocol Function List
Baud Rate : 9600
Data Bits: 8
Parity: None
Stop Bits: 1 
Flow Control : None
UART16550 FIFO: Disable
Projector Return (Pass): P
Projector Return (Fail): F 
1.   There is a  after 
all ASCII commands.
 
2.   0D is the HEX code 
for  in ASCII 
code.Optoma ES523ST/EW533ST RS232 Command Table  -------------------------------------------------------------------------------------------------------------------------------...

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------------------------------------------------------------------------------------------------------------------------------- ---------------------------------------------------------- ---------------------------------- 
~XX60 1  7E 30 30 36 30 20 31 0D  Format   4:3    
~XX60 2  7E 30 30 36 30 20 32 0D     16:9-l (for ES523ST) / 16:9 (for EW533ST)     
~XX60 3  7E 30 30 36 30 20 33 0D     16:9-ll (for ES523ST) / 16:10 (for EW533ST) 
~XX60 6  7E 30 30 36 30 20 36 0D     Native...