3. REPLACEMENT OF MEMORY IC
1. MEMORY IC.
This TV uses memory IC. In the memory IC are memorized data for correctly operating the video and deflection
circuits.
2. PROCEDURE FOR REPLACING MEMORY IC
(1) Standby off
Switch the power off and unplug the power cord from AC outlet.
(2) Replace IC
Be sure to use memory IC written with the initial data values.
(3) Standby On
Plug the power cord into the AC outlet and switch the power on.
(4) Check and set SYSTEM default value:
1) Press ?MUTE? A ?CALL? A ?-\--? A ?CALL? A ?MUTE? buttons in sequence to enter into factory
status.
2) If the memory IC haven?t been written with the initial data, press [Program+] / [Program-] to select item
INIT and press [VOLUME+] / [VOLUME-] to start initialize memory IC.
3) Check the setting value of the SYSTEM default value of Table below. If the value is different, select
items by [Program+] / [Program-] keys and set value by [VOLUME+] / [VOLUME-] keys.
4) Press ?EXIT? button to return to the normal screen.
4. SERVICE ADJUSTMENT
Specific operation: use remote controller
Press ?MUTE? A ?CALL? A 53. REPLACEMENT OF MEMORA ?CALL? A ?MUTE? buttonsY IC in sequence to enter into factory mode.
Press [Program+] / [Program-] to select items and press [VOLUME+] / [VOLUME-] key, to make data adjustment
of corresponding factory menus.
Press ?EXIT? key to exit factory mode.
Focus adjustment
1. Receive a crosshatch signal.
2. While watching the screen, adjust the FOCUS VR on the FBT to make the vertical and horizontal lines as
fine and sharp as possible.
Geometrical adjustment
Receive NTSC standard complete pattern signal.
Adjustment steps�
a) Adjust VSL, to the centre horizontal line just appears from half bottom shadow.
b) Adjust VAM, to get 92% of vertical picture contents would be displayed on CRT.
c) Adjust VSH, the centre horizontal line corresponds to CRT vertical centre.
d) Adjust SCL, to the linearity of P card field is in proper condition.
e) Adjust HSH, to get the picture horizontal centre correspond to CRT horizontal centre.
Receive NTSC signal and repeat above adjustment.
AGC Adjustment
Receive 60dB? (1mV) VH colour bar pattern signal.
Select TOP item.
Adjust value, to noise reduce gradually and just disappeared point.
CRT cut off and white balance adjustment
a) CRT cut off adjustment
1. Select item VG2B, then adjust value to 42.
2. PRESS ?0? key, when the screen shows?VG2? adjust the SCREEN control on Fly back transformer to
make the screen show alternating flashing characters of ?INSIDE HIGH INSIDE LOW?.
b) White balance adjustment
1. Receive a Black and White pattern.
2. Adjust WRP, WRG, WRB items to get colour temperature 9300K ?3 JND.
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ACEC
