NEC MultiSync 3D JC-1404HME Service Manual page 21

3-1) DEF PWB Adjustment
Al Analog Adjustment
(1) Horizontal Hold
a) Short TP501 and the ground.
bl Receive signal 1 (15kHz) and adjust horizontal hold (1) VR501
Sor that there is one screen.
c) Receive signal 2 (38kHz) and adjust horizontal hold (2) VR501
So that there is one screen.
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d) Receive the signal 1 and confirm that there is nearly one screen. If not, re-perform b) and c).
e) Remove the short between TP501 and the ground.
(2) High Voltage Adjustment
Recieve signal 8 (31.5kHz) and adjust high voltage adjustment VR504 so that the high voltage is
23.5kV with the CRT anode current cut off.
Due to DHHS, after adjusting, seal with an adhesive (TSE-385RTV) or cap (74004891 ).
(3) Horizontal Raster Centering
Receive signal 8 (31.5kHz) and check that the horizontal linearity is suitable. If it is extremely
bad, adjust to a suitable point with L504 (H. LIN. COIL).
Turn the brightness control fully clockwise so that back raster appears, then reinsert connector
RH so that the back raster is in the center of the CRT screen.
CRT /
RH 1
CJ .-
No correction
RH2
CJ .-
Correction 2mm
RH3
CJ .-
Correction 4mm
(4) Side Pin Cushion
For horizontal correction, set with
the direction of the connector.
Receive signal 8 (31.5kHz) and adjust VR403 for the optimum side pin cushion distortion.
Adjust so that pin distortion is zero (straight) at one side or both sides.
(5) Horizontal Linearity
Receive Signal 5 (22.0kHz) and adjust L504 for the optimum horizontal linearity.
(Reference: Optimum is that the magnet is turned about 45° clockwise or counterclockwise.)
(6) Horizontal Width
a) Short TP151 and TP152.
b) Receive signal 8 (31.5kHz) and adjust width coil L503 for a horizontal screen size of 240±2mm.
NOTE: Do not touch the Horizontal Size Control Switch of the front panel until Horizontal Width
Coil Adjustment is finished. Because the microcomputer's output voltage for the Horizontal
width adjustment will change once the test pins have been shorted.
Adjust after that video area is nearly center of the raster with Horizontal Position Switch and
Vertical amplitude is less than over scan (about 18mm) with Vertical Size Switch.
If Horizontal Size Control Switch is pushed by mistake, turn off the power switch and re-
adjust.
Bl Digital Memory Adjustment
Confirm that the adjustments as shown below are finished before performing this adjustment.
1. High Voltage Adjustment
2. Width Coil Adjustment
3. Horizontal Raster Centering Adjustment
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