B+ Adjustment; X-Ray Test; Adjustment; H-Raster Center Adjustment - NEC MultiSync V720 Service Manual

(5) B+ Adjustment

(A) MODE: No. 12.
(B) Pattern: Full white. (Brightness just cut off)
(C) Adjust VR101 to make the cathode of D112 has 13.6V.
(D) Check other power source should be 78 ¡Ó

(6) X-RAY Test

(A) Mode: No.12
(B) Pattern: Normal Crosshatch (Brightness just cut off)
(C) Test
1. Use Hi-Voltage probe
2. Adjust VR102 until X-RAY protector is operated, then check the protection voltage
should be 29.5KV or less.
3. After X-RAY protection test, turn back the VR102 position to center.
(7) H. V. Adjustment
(A) Mode: No. 12
(B) Pattern: Full White(Brightness just cut off)
(C) Adjust VR102 to make the cathode of D114 has 117V (LG CRT), 118V (Samsung CRT),
103V (TOSHIBA CRT), 117V (Matsushita CRT).
(D) Check the high voltage is 25.8kV ¡Ó

(8) H-Raster Center Adjustment

(A) Mode: No. 18
(B) Pattern: Crosshatch Reverse
(C) Adjust the Brightness Control that the background can be visible.
(D) Change SW301 position to make the mostly near center background position.
(9) Mode 12 Pre-Adjustment
(A) Mode: No. 12
(B) Pattern: Crosshatch
(C) Enter to Factory mode. Adjust H-phase, V-center, H-size, V-size, Pincushion, Trapezoid,
Bow, Parallelogram, and rotation to make Picture Position Center and Picture Size
310*232mm.

(10) White Balance Adjustment

(A) Setting

Enter Factory Mode,
Mode: No. 12, Pattern: Full White.
Warm up 30 min.
Make External Degauss.

(B) Cut Off Adjustment

1. Select the color Mode 9300K
2. Cut Off Adjustment: Video Signal Off (0.vp-p), Bright Control set to Mex., Adjust VR301
(VR307 for Toshiba CRT), at the Brightness 1~1.5FL. (3.4~5.1 cd/m2)
¡Ó2V, 6.2V ¡Ó ¡Ó0.3V, 53.5V ¡Ó
¡Ó ¡Ó
¡Ó ¡Ó ¡Ó ¡Ó
¡Ó
¡Ó1kV.
¡Ó ¡Ó
18
¡Ó1.5V,-11.5V ¡Ó ¡Ó ¡Ó
¡Ó0.5V.
¡Ó ¡Ó ¡Ó ¡Ó