Daewoo 103FH, Service Manual

Page: 19 / 58

17
2. No Raster
Trouble in
power supply
circuit
Trouble in video
circuit
Trouble in G1
line of Main PCB
Trouble in HVG
Trouble in G2
of HVG
Trouble in 80Vdc
line of power
supply unit
Refer to trouble
in P.S.U
Refer to trouble
in P.S.U
Is CRT
heater red-hot?
No
No
No
No
No
No
No Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Is Heater
Voltage (CRT PCB)
about 6.3V?
Turn the Brightness
& Contrast control
fully Maximum
No Raster
Is whole
screen bright?
Check
G1 voltage about
-35V?
Is 80Vdc
line normal?
Does
turning the G2 VR in HVG
counterclockwise
make screen
bright?
Is CRT
G2 (screen) voltage
about 490V?
Trouble in
CRT
Trouble in HVG