7 Troubleshooting
7-24
CHA42*7L/5**7L
7-2-21 Horizontal Blank Failure
7-2-23 Spot at Center During Power Off
7-2-22 Whistle Sound
Check trans coil
(L401,
T501, T601, CRT)
Is H_Blank waveform on
Q510’s collector?
Check CN202 and CN202_2.
Check and replace IC101.
Check and replace C503, C516,
R540, C515.
No
Yes
Are Q504 and D517 ok?
Replace it.
Yes
No
Symptoms: – Dark image and if shifting image to left or right side, image is rolled.
– Raster left or right side is rolled.
Does G1 voltage vary from
–60~80 Vrms to –200 Vrms during
power off time? (After falling
down to –200V, G1 voltage is
slowly increased to 0V).
Check and replace CRT.
No
Yes
32
31
Are 12 V line and Q504 ok?
Replace it.
Check and replace D510, R513,
R521, R520, C518.
Yes
No
WAVEFORMS
31
5.36 V (Q510, Collector)
CH1 P-P = 5.36 V
CH1 RMS = 4.210 V
WAVEFORMS
32
158 V (CN202, G1)
CH1 P-P = 158 V
CH1 RMS = 151.1 V
Summary of Contents for CHA4217L
Page 2: ...Samsung Electronics Co Ltd August 1998 Printed in Korea Code No BH68 61127A ...
Page 10: ...Memo 3 Product Specifications 3 4 CHA42 7L 5 7L ...
Page 14: ...5 Disassembly and Reassembly 5 2 CHA42 7L 5 7L Memo ...
Page 62: ...9 Electrical Parts List 9 14 CHA42 7L 5 7L Memo ...