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18
2. No Raster
Trouble in
power supply
circuit
Trouble in power
supply circuit
Trouble in G1
line of Main PWB
Trouble in FBT or
peripheral circuit
High Voltage
trouble in FBT
Trouble in 77Vdc
line of power
supply unit
Refer to trouble
in P.S.U
Refer to trouble in
power supply unit.
Is CRT
heater red-hot?
No
No
No
No
No
No
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Is Heater
Voltage (CRT PWB)
about 6V?
Turn the Brightness
& Contrast control
to set Maximum
No Raster
Is whole
screen bright?
Check
G1 voltage about
-72V?
Is 77Vdc
line normal?
Does
turning the Sub-
Brightness control to the
maximun on OSD menu
make screen
bright?
Is CRT
G2 (screen) voltage
about 450~
600V?
Trouble in
CRT
Trouble in FBT
TROUBLESHOOTING HINTS