Mitsubishi Electric PD-4225S, Service Manual

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Page 6
MODEL: PD-4225S
ELECTRICAL ADJUSTMENTS
Test Equipment
• DMM
• Signal Generator: RGB (VGA) - 1024x768, 60Hz, COMPONENT (YPbPr) - 1280x720p, 60Hz
Notes
• Do not attempt an adjustment if proper equipment is not available.
• Because this is not a Hot chassis, no isolation transformer is required. However, the use of an isolation transformer
will help protect test instruments.
• Perform only the adjustments required, in the correct order.
• Adjustment conditions… Temperature: 68°-86°F. Humidity: 55%-75%. Line Voltage: 100-240V, 50/60 Hz.
• Prior to adjustment, the PDP must be operated for at least 15 minutes while receiving a 100% white pattern.
• CAUTION: If a stationary pattern (i.e. Cross Hatch or digital generator) is displayed for more than 20 minutes, an
after image (image burn) can occur.
1. PWB Power Assembly Adjustments (Va, Vs Voltage Adjustments)
These adjustments must be performed after the repair or replacement of the PWB Power Assembly, or after replacing
the PDP.
A. Va Adjustment
1. Supply a 100% White pattern.
2. Connect a DMM between the Va and GND pins of P805 on the PWB Power. See
Figure 4 .
3. Note the Va voltage listed on the label located on the panel, top right side.
4. Adjust RV601 so the voltage is equal to the voltage listed, ± 0.5V.
B. Vs Adjustment
1. Connect the DMM between the Vs and GND pins of P805.
2. Note the Vs voltage listed on the label located on the panel, top right side.
3. Adjust RV401 so the voltage is equal to the voltage listed, ± 0.5V.