CHA42*7L/5**7L
7-1
7 Troubleshooting
7-1 General 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.
7-1-1 No Picture
Check signal cable connection, H/V Sync input.
Check Timing mode (14”: 30~55kHz, 15”: 30~61kHz).
Check Cont, Brit key (all Max) and Screen VR (G2).
Check key components of secondary part. :
Q402, Q508,
D515, D403,
D408,
D409,
Q410,
Rectifier
diodes (
D615,
D611, D608, D616, D617),
IC101
(Vcc~GND)
Check key components of primary part. :
FH601,
TH602,
D604 ~ D607, IC602,
OP601
Check SW211 (Power key) : Does IC202’s #2 voltage vary
vary from 5V to 0V, when pressing SW211?
Refer to 7-2-16 No Video.
Refer to 7-2-1 No Power.
Refer to 7-2-3 No Raster and 7-2-12 High Voltage Failure.
Refer to 7-2-17 Micom Failure.
Refer to 7-2-13 I
2
C Failure.
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 ...