Panasonic PT47WX34J - 47" PROJECTION TV, Service Manual

Page: 154 / 225

6. To check ABL apply a white pattern and put user bright control to
max. and confirm that reading on meter is 12.4 ± 0.8_V.
17.17. Red, green& blue screen Cut-Off
1. Use either a no input signal condition or raster from the NTSC
generator.
2. Observing the green tube directly or via a reflective surface, adjust the
VR on focus pack for the green tube for minimum noise.
3. Adjust the noise level in the red and blue tubes to match the noise
level in the green tube.
17.18. White balance adjustment
NOTE:
1080i, 480p, 480I pattern can be obtained from Panasonic’s TU-DST51 set-top box DTV decoder.
Prior to this adjustment, perform sub-contrast adjustment. This adjustment requires that the service
use skills in observing what a screen without color should look like (white picture).
Preparation:
1. Set the following in the user picture menu as follows:
- PIC MODE to VIVID
- COLOR to center (31)
- PICTURE to max (63)
- BRIGHT to center (31)
- SHARPNESS to min. (0)
- TINT to center (31)
- NATURAL COLOR to OFF
- COLOR TEMPERATURE to COOL
1. Enter the service mode.
2. Apply a NTSC black and white pattern to one of the video inputs (see
above note) color bar with no color.
17.18.1. High light white balance adjustment
1. Adjust DAC R_DR for red and B_DR for blue adjustments.
2. Make sure the screen is not blue or green. The screen should be white
51