NEC PlasmaSync PX-42VM1G, Service Manual

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6-4. PC 400 line mode check
(1) Apply a PC mode 3 (Program No.3 PC98 400@56Hz) input to the RGB1 input terminal and select PC
INPUT.
(2) Confirm that a normal display is presented.
(3) After selecting [POSITION] on the screen by the use of the PROCEED key, set up [FULL] with the
WIDE key and confirm that the screen size is normally changed over.
6-5. PC VGA mode check
(1) Apply a PC mode 5 (PC98 480@60Hz Program No.5) input to the RGB1 input terminal and select PC
INPUT.
(2) Confirm that a normal display is presented.
(3) Change over the display signal to the lamp waveform and confirm that a normal display is presented.
When a vertical stripe pattern is seen, try to display a monotonous color lamp waveform and check for
any abnormal signal line (Signal R system, or Signal G system, or Signal B system).
(4) Press the WIDE key of the remote control to change the screen mode and confirm that there is a
normal variation of [NORMAL]
→
[FULL]
→
[NORMAL].
6-6. PC SVGA mode check
(1) Apply a PC mode 11 (VESA 600@56Hz No.11) color bar plus circle signal input to the RGB/PC input
terminal and select PC INPUT.
(2) Confirm that a normal display is presented.
6-7. APL correction data check
* The slide switches SW4012 to SW4015 on the jig board should have been set at the lower side (set at Lo).
(1)
Apply a PC mode 5 (PC98 480@60Hz Program No.5) input to the RGB1 input terminal and select PC
INPUT. Enter an input of color bar signal.
(2) Connect an oscilloscope to the check terminals of [PSC0] to [PSC3] on the jig board.
(3) Confirm that a signal of 5Vp-p (Hi) is seen at each check terminal when the slide switches SW4012 to
SW4015 are simultaneously moved to the upper side (set at Hi).
6-8. Fan stop detection
(1) Open the short-circuited section between TP9701 and TP9702 of the MAIN PWB.
(2) Confirm that the LED (green) of the CTL PWB flashes at the intervals of 500ms and that the condition
of remote control standby (power is fed only to the microcomputer) is assumed.
(3) Confirm that POWER ON/OFF is impossible only with the remote control key.
(4) Turn off the main POWER switch.
(5) Short-circuit the opened section between TP9701 and TP9702.
(6) Turn on the main POWER switch.
(7) Confirm that the power supply circuit is turned on and the steady state is recovered.
* When a DC fan or a dummy is used, open the section between TP9701 and TP9702, and confirm
that the condition of fan stop is detected when the said DC fan or the dummy is operated.
6-9. Panel cracks detection signal check for short-circuit testing
(1) Short-circuit the silk side of [!!] of the jumper pin JP4010 on the jig board.
(2) Confirm that the LED (orange) of the CTL PWB flashes at the intervals of 500ms and that the condition
of remote control standby is assumed.
(3) Confirm that POWER ON/OFF is impossible only with the remote control key.
(4) Short-circuit the [
▲
silk] side of the jumper pin JP4010 on the jig board.
(5) Pressing the INPUT SELECT key of the CTL PWB, take an action of [OFF]
→
[ON] for the main power
supply.
(6) Confirm that the power supply circuit is turned on and the steady state is recovered.
5-10
METHOD OF ADJUSTMENTS