HP 16500A Service Manual page 55

HP 16500A/16501A - Adjustments
White Balance
1. From the Display Test menu, select a blank (colorless) raster.
2. Set the front panel BACKGROUND and SUB BRT (RV901), located on the bottom PC board, to
mechanical center.
3. Set the front panel BRIGHTNESS and SUB CONT (RV902), located on the bottom PC board, to
mechanical center.
4. Set the G. DRIVE (RV921), B. DRIVE (RV931), and R. DRIVE (RV911), located on the bottom PC
board, to mechanical center.
5. Set the G.BKG (RV721), B.BKG (RV731), and R.BKG (RV711), located on the rear PC board, fully
counterclockwise (CCW).
6. Adjust the SCREEN (RV702), located on the rear PC board, until either a red, green, or blue raster
just starts to become visible. Note which color becomes visible first and do not adjust background
control (BKG) for that color in the next step.
7. Adjust the other two background (BKG) controls for the best white balance.
8. From the Display Test menu, select the white raster test pattern.
9. Set the front panel BRIGHTNESS control to maximum.
10. Observe the screen and adjust the DRIVE controls (RV921, RV931, and RV911), located on the
bottom PC board for the best white balance.
Using an average piece of white photocopy paper, compare the white on the
CRT to the paper.
11. Repeat steps 1 through 3 and 6 through 10 until the white balance is acceptable.
12. Reinstall the cooling fans. Refer to section 6, "Service," for the fan installation procedures.
4-20
Note
Any text on the screen will not affect this adjustment.
Note