NEC MultiSync 2A Service Manual page 16

(6) Vertical Sub Height
Receiving all white signal, adjust VR452 so that vertical screen size is 180 mm.
(7) Side Pin Cushion
Adjust VR401 for the optimum side pin cushion distortion.
(8) Horizontal Width (when receiving all white signal)
a) Receiving signal 4 (MAC11), adjust L504 (H. WIDTH COIL) so that horizontal width is 235 mm.
b) Receiving signal 1 (VGA), adjust L503 (H. WIDTH COIL) so that horizontal width is 240 mm.
NOTE: Adjustment must be conducted starting from a), then b).
3-2) Adjustment of Video Amplitude and White Balance
NOTE: Check that the video signals are as shown below before performing the main adjustment. In
particular, for L VG - 1600, the video signal output level varies according to the signal
pattern, so check the level with the signal to be adjusted.
Video: Analog 0.7Vp-p
Synchronizing: Separate TTL level
Unless otherwise specified, use signal 1 for video adjustments.
(1) Initial Settings of Adjustment VRs
VR701, 702, 703 GAIN VR
VR710
SUB CONT VR
VR704, 705, 706 BIAS VR
VR707, 708, 709 SUB BRIGHT VR
(2) Video Contrast Adjustment (Signal 1: Window pattern)
a) GAIN VR adjustment
(j)
Receive the window pattern.
CD
Contrast control
Brightness control
CD
Adjust VR701, VR702, and VR703 so that the R, G, and B outputs (TP701, 702, 703) on the
VIDEO PWB are 36 Vp-p.
After adjusting, check the Vp-ps again and reajust if they do not conform to the settings.
b) SUB-CONT. VR adjustment
(j)
Contrast control
Brightness control
0
Adjust VR710 so that the G (TP702) output on the CRT PWB is 10Vp-p.
After adjusting, check that the R (TP701) and B (TP703) outputs are 10Vp-p ±0.5Vp-p.
If not, fine-adjust VR710 so that the R, G, and B outputs are within the range of 10Vp-p
±0.5Vp-p.
Fully counterclockwise
Fully counterclockwise
Fully clockwise
Center
Fully clockwise
Fully counterclockwise
Vp-p
Fully counterclockwise
Fully clockwise
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Vp-p