LG / GOLDSTAR MT-50PZ41H
Service Manual

ADJUSTMENT INSTRUCTIONS
1. Application Object
These instructions are applied to all of the PDP monitor, RF02CA.

4. MAX Bias Adjustment
(1) Input Full White (255 Gray) signal which generated from Pattern Generator into CVBS and RGB1 Input part. (2) Press POWER ON KEY on R/C for adjustment and select MAX-BIAS (3) Press Vol. + key and operate TO SET (4) Original Full White screen will be presented about 1~2 seconds later. And if there is a mark of OK OSD, then the Min-Bias adjustment will be completed. (5) After adjustment, press ¥ key to save adjustment and come out of the adjustment mode.
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2. Notes
(1) Because this is not a hot chassis, it is not necessary to use an isolation transformer. However, the use of isolation transformer will help protect test instrument. (2) Adjustment must be done in the correct order. (3) The adjustment must be performed in the circumstance of 25±5°C of temperature and 65±10% of relative humidity if there is no specific designation. (4) The input voltage of the receiver must keep 110~240V, 50/60Hz in adjusting. (5) The receiver must be operated for about 15 minutes prior to the adjustment. 1) After receiving 100% white pattern(06CH), the receiver must be operate prior to adjustment. (Or white condition in HEAT-RUN mode) 2) Enter into HEAT-RUN mode - Press the POWER ON KEY on R/C for adjustment. - OSD display HEAT-RUN WHITE and screen display 100% full WHITE PATTERN. [ Set is activated HEAT-RUN without signal generator in this mode. [ Single color pattern of HEAT-RUN mode uses to check PANEL. (RED/BLUE/GREEN)
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You can check whether circuit adjustment is operated well or not, as below. (1) Display RGB1 to the Main picture, CVBS to the Sub picture in the TWIN PICTURE. (2) To check the MIN-Bias, input Full Black (0 gray) signal into CVBS and RGB1 input part at the same time in the Pattern Generator. (3) To check the MAX-Bias, input Full White (255 gray) signal into CVBS and RGB1 input part at the same time in the Pattern Generator. (4) Compare Black Level with White Level by eyes. And if there is no Level difference, the adjustment is completed well.

Data value, which adjusted in the board, is valid until the VSC Board is dissued and must be protected. For the protection of data, Micom does not permit any more adjustment after completion. O In case of re-adjustment, operate First Value Setting.

[Caution] If you turn on a still screen more than 20 minutes (Especially Digital pattern(13 CH), Cross Hatch Pattern), a afterimage may be occur in the black level part of the screen.

Each PCB Assy must be checked by Check JIG Set before assembly. (Especially, be careful Power PCB Assy which can cause fatal Damage to PDP Module.)

3. RGB Auto Cut-Off & MIN Bias Adjustment
(1) Input Full Back (0 Gray) signal which generated from Pattern Generator into CVBS and RGB1 Input part. (2) Press POWER ON KEY on R/C for adjustment and select AUTO-CUT(Cut-off Auto Adjustment) (3) Press Vol. + key and operate TO SET (4) Screen adjustment starts with Full Black screen. Original Window screen will be presented about 5-6 seconds later. And if there is a mark of OK OSD, then the Auto Cut-off and Min-Bias adjustment will be completed. (5) Pass to the next MAX Bias Adjustment after Adjustment. [ Replace PDP Module or Power Board, adjust certainly Power PCB Assy Voltage.

5. POWER PCB Assy Voltage Adjustment (Va, Vs Voltage Adjustment)
5-1 Test Equipment : D.M.M 1EA 5-2 Connection Diagram for Measuring
Refer to Fig 1.

5-3 Adjustment Method
(1) Va Adjustment
1) After receiving 100% white pattern, HEAT RUN. 2) Connect + terminal of D.M.M to Va pin of P805 and connect � terminal to GND pin of P805. 3) After turning the VR4, voltage of D.M.M adjustment as same as Va voltage which on label of panel Right/Top. (Deviation : ±0.5V)

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