Acer AM501 AM501 Monitor Service Guide - Page 30

5.0 ALIGNMENT PROCEDURE Warm up the monitor for at least 30 minutes before adjustment. Set the front of CRT to the east. Turn all VR set to center position. 5.1 B+ Voltage, G1, H. Position Adjustment Use front control key adjust the display size about 260mm, adjust VR501 let the voltage of FBT PIN3 cathode is 139±0.3V. (Timing is 48k 1024x768.Pattern is full white.) 5.2 White Balance Adjustment EXT. BRIGHTNESS and EXT. CONTRAST set MAX. 1. Input timing 48k 1024x768 without pattern adjust G2 VR (mounting on F.B.T) so that the brightness of back raster to become 0.5? 0.1 FL and adjust VR301 VR33 VR361,let the x-coordinate, Y-coordinate be inside spec range. 2. Adjust Brightness to cut-off (Raster), then adjust VR801 let the brightness is 45 ± 1FL (2" pattern). 3. Adjust Bri & Cont. to max, then adjust VR802 let the brightness is 32 ± 1FL (Full white), and adjust VR201, VR231, let the X-coordinate, Y-coordinate be inside spec range. 4. All the value must be check repeatedly. 5.3 Focus Adjustment 1. EXT. BRIGHTNESS move to cut off point. Use EXT.CONTRAST set the brightness to 25FL. 2. Adjust Focus VR (mounting on F.B.T), to get best focus. 5.4 Preset Timing Adjustment (Short P102 or press recall key when power on) 1. Input each PRESET MODE timing, and use front control key adjust the display to the normal position and size, and wait for 2 seconds. 2. Switch to next timing repeat 1 process. Unitl every PRESET MODE timing have been adjusted. 26