Samsung SyncMaster CSH7839L Service Manual page 31

7-1-7 Abnormal H_Size
IC201 Pin 5 output duty varies
with different B+ offset DAC
values?
Yes
T402 Pin 8 waveform is right?
10
Yes
Check some parts around D407.
7-1-8 Side Pin or Trap Failure
IC251 Pin 24 output exists?
11
Yes
Check and replace IC401.
Check some parts IC401 Pin 2
and IC251 Pin 24.
7-1-9 Para. or Pin Balance Failure
IC251 Pin 5 output varies with
different DAC values?
No
Replace IC251.
CSH7839L/CSH9839L
Check and replace IC201.
No
Check some parts IC201 Pin 5,
IC251 Pin 28 and IC401 Pin 2.
No
Check and replace T402.
No
Check and replace IC251.
7 Troubleshooting
WAVEFORMS
54 V (Q406, Drain)
10
CH1 P-P = 54 V CH1 RMS = 22.44 V
WAVEFORMS
11 11.6 V (Q406, Gain)
CH1 P-P = 11.6 V CH1 RMS = 6.944 V
7-5