Daewoo 710B Service Manual page 23

6-2. V.OSC/Deflection Circuit
45Vp-p
Unstable or
Abnormal picture
Is
13V DC line
correct?
Yes
Is
the output
waveform of IC401
(pin 6) normal?
No
Is the
output pulse
of IC501 (pin 23)
normal?
No
Trouble in V.Sync line
or IC501 failure.
21
No
Trouble in
power supply unit
Yes
V.DY
failure
Yes
Trouble in IC401 or
its ambient circuit