Samsung CKF5607L Service Manual page 29

7-4 No Raster (1)
If in a protection case, you must check these case
• Check CN401 and CN402.
• Check Screen VR.
• Check VR501.
Does secondary voltage
appear at D608, D609, D610,
D611 and D612?
Yes
Does DC 12 V appear at Pin 2 of
IC603?
Yes
Does H-out signal appear at Pin
6
26 of IC401?
Yes
Does signal appear at base
of Q405?
Yes
Does signal appear at collector
of Q405?
Yes
Does flyback signal appear at
14
collector of Q410?
Yes
Does switching pulse appear at
22
base and collector of Q509?
23
Yes
Does signal appear at gate
of Q512?
Yes
Check Q512, D511, D508 and FBT.
CKF5607L
No
Check Power parts.
No
Check protection case.
No
Does DC +5 V, DC +12 V appear
at Pins 29, and 32 of IC401?
Yes
No
Check Q403 and Q404.
No
Check Q405.
No
Check Q410.
No
Check Q506, Q507, Q508 and Q509.
No
Check IC501 and FBT.
7 Troubleshooting
WAVEFORMS
6 9.24 V (IC401, #26)
CH1 P-P = 9.24 V CH1 RMS = 6.048 V
No
Check IC600
and IC603.
Check IC401.
14 1.072 kV (Q410, Collector)
CH1 P-P = 1.072 kV CH1 RMS = 310.0 V
22 6.80 V (Q509, Base)
CH1 P-P = 6.80 V CH1 RMS = 1.456 V
23 952 V (Q509, Collector)
CH1 P-P = 952 V CH1 RMS = 307.2 V
7-3