Sharp LC-20B8US, Service Manual

Page: 13 / 128

13
LC-20B8U-S
LC-20B9U-S
LC-20B9U-SM
ADJUSTING PROCEDURE OF EACH SECTION
1. Preparations before adjustment
(1) Keep the AC power cable directly plugged in a wall outlet.
AC110V~240V
[1] Adjustment procedures
1-1. Adjusting the checker
Power on (initialization)
→
Setting the model number and screen size
1-2. Finishing process adjustments
Assembling
→
Power on
→
Adjustment process mode (bus connector)
→
AD converter level, common bias,
TAMP and white balance (cut-off and gain) adjustments
[2] Entering the checker mode/adjustment process mode
2-1. Calling the checker mode
* Keep KEY-5 (pin (82) of microprocessor) at "L" level and turn on the power.
KEY-4 KEY-5 Mode shift
H H Normal mode (Fresh data written and saved on EEPROM)
L H Shift to adjustment process mode
H L Operation with master ROM settings in the checker mode (EEPROM still brand-new after the checker mode)
L L EEPROM initialized and microprocessor's master settings written (process adjustment values not yet written)
2-2. Calling the adjustment process mode
There are two ways to call this mode.
* Keep KEY-4 (pin (81) of microprocessor) at "L" level and turn on the power.
* For servicing:
1
Hold down the "INPUT" and "VOL (–)" keys at once, and turn on the power switch. ("K" appears
at the top left onscreen to indicate that the checker mode is on.)
→
2
Press the "CH (
Ù
)" and "VOL (–)" keys at
once. (The adjustment process mode screen shows up.) ..... To quit the mode, turn off the power (using the power
switch on the set or the remote controller).
[3] Key operation
Ë
Basic operation
* Using the "CH (
ù
)/(
Ù
)" keys, select a receiving channel.
* Using the "INPUT" key, select an input.
* Using the "cursor up/down keys, select an adjustment item. (When the "cursor down" key is pressed at the bottom
item of a page, the top item on the next page will be selected. When the "cursor up" key is pressed at the top item
of a page, the bottom item on the previous page will be selected.)
* Using the "VOL (+)/(–)" or "cursor right/left" keys, adjust the selected item.
* Press the "MENU" key, and the next item will be selected. (When the "MENU" key is pressed at the bottom item
of a page, the top item on the next page will be selected.)
Ë
Hierarchical shift
* Press the "ENTER" key on any item other than I2C DATA on Page 9, the setting page of the item will show up.
* To quit the setting page, press the "FLASHBACK" key.