Samsung CKE5507 Troubleshooting
CKE5507L/LM 7-1
7 Troubleshooting
Notes: 1. If a picture does not appear, fully rotate the brightness and contrast controls clockwise and reinspect.
2. Check the following circuits.
• No raster appears: Power circuit, Horizontal output circuit, H/V control circuit, and H/V output circuit.
• High voltage develops but no raster appears: Video output circuits.
• High voltage does not develop: Horizontal output circuits.
7-1 No Power
Does proper AC 90-264 Volts
appear between the positive and
negative poles of C606?
Check F601 and L602.
Check D604~D607, IC602, T601,
OP601, and power circuit.
Yes
No
Check IC301 and its
related circuits
Check the power supply circuits
(D616)
Check the power supply circuits
(D608)
7-2 Horizontal Line on CRT
Does DC 13 V appear at
Pin 2 of IC301?
Does DC -11 V appear at
Pin 4 of IC301?
Yes
No
No
Replace IC301 or check its
related circuits
(D301, IC301 and R312)
Does the output pulse of
48 Vp-p appear
at Pin 5 of IC301?
Yes
Yes
No
WAVEFORMS
13
38.8 V (IC301, #5)
CH1 P-P = 38.8 V CH1 RMS = 4.26 V
13
7 Troubleshooting
7-2 CKE5507L/LM
7-3 No Raster
Check the horizontal drive
circuits. (IC401)
Does the drive pulse appear
at Pin 26 of IC401?
Yes
No
Check Q403 and T401
Does the drive pulse
appear at the collctor of
Q403?
Yes
No
Check its related circuits
(R414 and C411)
No
WAVEFORMS
21
19
Check flyback pulse at the
collector of Q402 connection of
CN502 and its related circuits
(D403, D409 and T501)
Does the drive output
pulse appear at the base
of Q402?
Yes
22
23
106.4 V (Q403, Collector)
CH1 P-P = 106.4 V CH1 RMS = 44.92 V
21
8.48 V (Q402, Base)
CH1 P-P = 8.48 V CH1 RMS = 1.252 V
22
3.80 V (IC401, #26)
CH1 P-P = 3.80 V CH1 RMS = 2.376 V
19
1.080 kV (Q402, Collector)
CH1 P-P = 1.080 kV CH1 RMS = 208.0 V
23
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