GE 27GT720TX1, Техническая сервисная информация

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MISCELLANEOUS ADJUSTMENTS
SET 4776 Page 1
NOTE: All procedures require an antenna connected and power applied to the set.
HIGH VOLTAGE CHECK
Tune in a picture. Set brightness, contrast, and color to minimum. Connect a high
voltage probe to the CRT anode. High voltage should measure 26kV to 28kV.
COLOR TEMPERATURE
NOTE: See Service Adjustment Parameters to change drive and bias values.
Press menu button for collapsed raster service line. Disconnect the antenna. Preset
the red, green, and blue drive values to 32. Adjust screen control for a service line
that is just visible. Adjust red, green, and blue drives to obtain a white raster. Check
the low light to high light gray scale tracking. Repeat the procedure, if necessary, to
obtain the best performance
SERVICE MENU
The following adjustment procedures are accessed thru a service menu. To access the service menu, turn the receiver on, press the menu button and hold it down while
pressing the power button. While holding down the menu button, release the power button and press the button. The screen will display a one line menu, on the
left the parameter P0, and on the right the value of that parameter V0. Release buttons. Adjustments are made by selecting the proper parameter and changing the value of
that parameter. To change the parameter number use channel up and down buttons. To adjust the current value of that parameter use and - buttons. To access and
change any of the adjustments, the proper parameter pass number must be entered. This information is listed at the beginning of the alignment. When these parameters are
modified, the T-Chip and the corresponding EEPROM are updated. All service adjustments are bus controlled, except focus and screen.
NOTE: In order to adjust the RF AGC, audio or video levels, tuner, PIP, or stereo circuits, the ChipperCheck hardware and software must be used. This can be purchased
from Thomson Electronics. Before making any changes to any of the values, record the On Set values.
SERVICE ADJUSTMENT PARAMETERS
Parameter On Set Value
No. Parameter Name Value Range Comment
0 Pass number for service Must set to 76
-
May not advance until value is set to 76
.
adjustment parameters
.
1 Error Code 1 0 0 - 255 Displays the first error detected. Set to 0 before exiting.
See Error Codes Chart.
2 Error Code 2 0 0 - 255 Displays the second error detected. Set to 0 before exiting.
See Error Codes Chart.
3 Error Code 3 0 0 - 255 Displays the last error detected. Set to 0 before exiting.
See Error Codes Chart.
4 Horizontal Phase 10 0 - 15 Tune in a crosshatch pattern, adjust to center the pattern on the screen.
5 EW DC (Width) 16 0 - 31 Tune in a crosshatch pattern, adjust for slight horizontal overscan.
6 EW Amplitude 8 0 - 15 Set value to 8.
7 EW Tilt 8 0 - 15 Set value to 8.
8 Top Corner Pin Correction 2 0 - 7 Set value to 2.
9 Bottom Corner Pin Correction 2 0 - 7 Set value to 2.
10 Vertical DC 33 0 - 63 Tune in a crosshatch pattern, adjust to center vertically.
11 Vertical Size 84 0 - 127 Tune in a crosshatch pattern, adjust for slight vertical overscan.
12 Vertical Countdown Mode 0 0 - 3 Set value to 0. (0 = Standard, 1 = Non-Standard, 2 = 50Hz, 3 = 48Hz)
13 Red Bias 30 0 - 127 Press menu button on the TV set for setup line.
14 Green Bias 15 0 - 127 Press menu button on the TV set for setup line.
15 Blue Bias 34 0 - 127 Press menu button on the TV set for setup line.
16 Red Drive 41 0 - 63 -
17 Green Drive 33 0 - 63 -
18 Blue Drive 32 0 - 63 -
19 Gemstar Horizontal OSD Position 166 0 - 255 Set value to 166.
20 Gemstar Vertical OSD Position 68 0 - 255 Set value to 68.
21 Gemstar PIP Horizontal Position 40 0 - 255 Set value to 40.
22 Gemstar PIP Vertical Position 43 0 - 255 Set value to 43.
23 Gemstar PIP Window Vertical Size 3 0 - 13 Set value to 3.
ERROR CODES CHART
ERROR CODE
DEC HEX Error Location Condition Indicated
0 00 No error code -
1 01 16.0V fault 16.0V STBY source is failing.
3 03 12.0V run fault 12.0V source is failing.
4 04 T4 Chip Run supply failed.
8 08 T4 Chip X-ray protection caused high voltage shutdown.
9 09 T4 Chip (POR) Power supply problem at (POR) power on reset.
10 0A F2 PIP module error (POR) Power supply problem at (POR) power on reset/PIP.
11 0B Stereo decoder (POR) Power supply problem at reset/Stereo decoder.
16 10 Run IIC Bus held low Run IIC clock or data held low.
18 12 Standby IIC Bus held low Standby IIC clock or data held low.
23 17 Gemstar 3 Board Guide fatal error on set using Gemstar 3 Board.
24 18 Gemstar 3 Board Task monitor error on set using Gemstar 3 Board.
25 19 Gemstar 3 Board Watchdog error on set using Gemstar 3 Board.
26 1A Gemstar 3 Board Task monitor error on set using Gemstar 3 Board.
32 20 Gemstar 3 Board CPU error on set using Gemstar 3 Board.
34 22 Gemstar 3 Board Gemstar 3 fails to acknowledge.
44 2C F2 PIP module error F2PIP fails to acknowledge.
102 66 Octal DAC Octal DAC fails to acknowledge.
128 80 Stereo decoder Stereo decoder fails to acknowledge.
160 A0 Main or PIP tuner EEPROM Main or PIP tuner EEPROM fails to acknowledge.
186 BA T4 Chip T4 Chip fails to acknowledge.
196 C4 Main tuner PLL/DAC Main tuner PLL IC fails to acknowledge.
198 C6 Main tuner PLL/DAC Main tuner DAC IC fails to acknowledge.
ERROR CODES
If certain failures occur, the matching error codes will be stored in the
EEPROM. These error codes will be displayed in parameters 1, 2, and 3.
The first failure error code will be stored at parameter 1 and the second
failure error code will be stored at parameter 2. Parameter 3 will be
updated to display the most recent failure occurred in the chassis. If a
failure of a bus IC occurred, the normal acknowledgment checking of that
bus will be disabled in the service mode and the address of that IC which
failed will be stored in one of the error code parameters. After every repair
is done to the chassis it is recommended to check the error code
parameters, and reset them back to value 0.