Acer AC501 AC501 Monitor Service Guide - Page 4

B-3. Picture Alignment White balance alignment Select timing #6(VESA 64K 1280x1024) with crosshatch pattern, adjust both horizontal and vertical OSD's size control to get di splay size within 262 x 196±1mm. Disconnect R×G×B signal inputs, adjust OSD's brightness control to i t's maximum position then adjust FBT's G2 control VR to get a DC voltage t o be obtained on CRT socket pin #7 as defined in following CRT type G2 Voltage SAMSUNG 550V+/-10V LG 550V+/-10V B-4. White Balance Aignment B-5. Select timing 6 VESA 1280X1024 with full field raster pattern (cut off R, G, B) Adjust H-size 260mm V-size 195mm B-6. Brightness and Contrast set to MAX adjust G2, has G2 Voltage to be 550V, then, adjust VR502 to get raster is 0.8fl. Adjust G DC-bias has Y=0.8FL B DC-bias has y=311 +/- 25 R DC-bias has x=281 +/- 25 Adjust Brightness to raster is 0.06fl. B-7: Select 2 inch one-square pattern, adjust color temperature 9300Celsius degree. Adjust G DC-Gain has Y=50FL+/-2FL B DC-bias has y=311 +/- 5 R DC-bias has x=281 +/- 5 B-8: Select white pattern, Double check x=281 +/-2 5 y=311 +/-2 5 Adjust SUB-Bright to get full white pattern, Y is 105 +/-3 cd/mm B-9: Same procedure, to get Color temperature 6500 x=313 y=329 5000 x=345 y=359 B-10. Focus alignment B-11. Select timing #6 (VESA 64k 1280x1024) with a 2 inch five-square pattern, adjust the OSD' s brightness control to get raster light output equial to 0.06 F-L then adjust OSD' s contrast control to get 35F-L at the center of center of the screen, select an alternating "me" pattern that fills the screen with letters that white on black then adjust FBT' s G4 control VR to get best focus on quarter position of CRT screen 4