Nokia 447ZiPlus Service Manual page 24

7-1. B+ Output Voltage Adjustment
a) Apply a VGA signal (53.6KHz) with cross hatch pattern to the unit.
b) Turn the brightness control and contrast control to the maximum.
c) B+ adj. (R833) for the voltage across C806 to be 56V +2V, -0.5V.
d) Verify the voltage on the table
Voltage
+6.3V
+14V
+75V
+55V
+12V
+5V
-9V
+8V
7-2. High Voltage Adjustment /Sub-Bright Adjustment
a) Apply a VGA signal (53.6KHz) with crosshatch pattern.
b) Set Contrast to maximum.
c) Adjust the Brightness or G2 VR on T440 until the raster just disappears.
d) Adjust HV. ADJ R321 for the high voltage to be 26kV ±0.2 kV.
e) Set the contrast and the brightness to the MAX.
7-3. H. Raster Center Adjustment
a) Apply a 69 kHz signal with crosshatch pattern.
b) Select the jumper on P402 to center the raster position, the background raster should
be centralized with respect to the edge of the bezel by proper insertion the P402.
Spec.
6.1V ± 0.3V
15V ±2V
80V ±6V
56.2V + 2V, -0.5V
+12V ±0.5V
5.1V ± 0.1V
- 9.5V ± 1V
+8.3V ±0.5V
22