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Troubleshooting hints, No character – Daewoo 531X User Manual

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15

TROUBLESHOOTING HINTS

1. No Character

Change the Contrast &
Brightness control value to
maximum

No Raster

Refer to
No Raster

Check the peripheral circuit
of CRT

Check the video output
circuit and its ambient circuit

Trouble in 12V line
of the Main PWB

Check the clamping pulse
circuit

Check the signal cable

No Character

Is whole

screen bright?

Yes

Yes

Yes

Yes

Yes

No

No

No

No

No

Yes

Yes

Rk, Gk, Bk

About 30~35Vpp

No

No

Is CRT

Cathode (Rk, Gk, Bk)

signal level

normal?

Is the

output signal of the

(pin 14, 16, 18) pre-amp

IC801, normal?

Is blanking

pulse (pin 20 of IC801)

normal?

Is 12V line

normal?

Is input signal

normal?

Trouble in IC801 and

its ambient circuit

5Vp-p

Are the Contrast &

Brightness Controls in

OSD menu

maximum?