Troubleshooting Hints - Daewoo 432X Service Manual

TROUBLESHOOTING HINTS

1. No Character
No Character
Are the Contrast &
Brightness Controls in
OSD menu
maximum?
Yes
Is whole
screen bright?
Yes
Is CRT
Cathode (Rk, Gk, Bk)
signal level
normal?
No
Is the
output signal of the
(pin 15, 19, 22) pre-amp
IC801, normal?
No
Is 8Vdc line
normal?
Yes
Is clamping
pulse (pin 23 of IC801)
normal?
Yes
Is input signal
normal?
Yes
Trouble in IC801 and
its ambient circuit
Change the Contrast &
No
Brightness control value to
maximum
No
No Raster
Yes
Check the peripheral circuit
of CRT
Rk, Gk, Bk
About 45Vpp
Yes
Check the video output
circuit and its ambient circuit
No
Trouble in 8Vdc line
of the Main PWB
No
Check the clamping pulse
circuit
12Vpp
No
Check the signal cable
14
Refer to
No Raster