Samsung CKE5507L, Service Manual

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7 Troubleshooting
CKE5507L/LM 7-3
Check screen VR of FBT and G2 Pin.
Check Q605, Q606 and D621~D623.
Power indicator is green
Check signal cable
and signal source
Does DC 12 V appear at
Pins 16 and 5 of IC101?
Does the video pulse
appear at Pins 4, 6 and 8
of IC101?
Check IC101
Check IC101.
Check clamp circuit on
the Main PCB and
IC202 (pin #37).
Check contrast control
circuit (on the Main
PCB)
Does the video pulse
appear at Pins 13, 17 and
19 of IC101?
Does the clamp signal
appear at Pin 37 of IC202?
7-4 No Video
Yes
No
Yes
No
Yes Yes
No
No
No
Does the video amplified
pulse appear at the Pins
8, 9 and 11 of IC102?
Yes
No
Does the video amplified appear
at the Pin #1, 3 and 5 of IC102?
Yes
Yes
Does the DC voltage appear
at pin 9 of IC 101?
No
32
Check CRT.
No
Does the right R, G, B waveforms
appear at the disconnected
Video PCB from CRT?
Yes
33
11
WAVEFORMS
40.8 V (IC102, #1)
CH1 P-P = 40.8 V CH1 RMS = 27.10 V
33
3.92 V (IC101, #19)
CH1 P-P = 3.92 V CH1 RMS = 3.536 V
32
4.52 V (IC202, #37)
CH1 P-P = 4.52 V CH1 RMS = 4.284 V
11