SAMSUNG PROJECTION TV SERVICE GUIDE
Section 2 -
Service Bulletins
Last update: 4/18//01
Subject:
White balance and gamma adjustment.
Background:
When the white balance and gamma adjustment can not be performed
by visual method, refer to method using test equipment.
Countermeasure:
Adjustment using test equipment:
Equipment:
1. NTSC signal generator, 10 – step signal. Each step of 10 IRE, last step is 100 IRE.
This can be confirmed by using waveform monitor.
2. Color & chromaticity meter (Minolta CS-100).
Procedure: Set the color temperature to the value listed below, using the color &
chromaticity meter with a specific step displayed by the signal generator. Adjust values
in the service mode to achieve good white balance and gamma. Refer to service
manual page 5-4 & 5-5. To enter service mode, press Mute - 1 – 8 – 2 with power off.
Power set on; service mode will be displayed.
1. High light 80 IRE: Y=(13+/- 3.0), x=(0.285+/- .007), y=(0.284+/- .007).
Use control No. 20(Sub contrast, 22(R sub contrast), 23(B sub contrast).
2. Mid light 40 IRE: Y=(2.4+/- 0.5), x=(0.284+/- .007), y=(0.272+/- .007).
Use control No. 15(Sub bright), 16(B sub bright), 17(R sub bright).
3. Low light 20 IRE: Y=(0.3+/- 0.1), x=(0.291+/- .007), y=(0.264+/- .007).
Use control No. 7(Gamma ctrl 1), 8(R gamma ctrl 1), 9(B gamma ctrl 1).
Note: Repeat adjustment of each control to achieve best results.
SERVICE BULLETIN
PRODUCT: PJT
BULLETIN: LCD-02
MODEL: All LCD models
