Service manual

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47
3. DC output voltage is unstable
Unstable power
Check sampling
Circuit
Check R822, R823,
R824
Change R822, R823,
R824
Check the R pin
voltage of IC803
about 2.5V
Check R819, R820
Check R818, D804, C807 if
short
Change R818,
D804, C807
Check pin2 of
IC802 voltage
is 3V
Check pin1 of
IC802 voltage
below 1V
Change R808, R 809,
R810, R 811, R815,
END
Check the C pin
voltage of IC803 if
3V
Change
IC803
VX1935wm-3