6 Troubleshooting
6-14
DP14L*/DP15L*
6-2-12 High Voltage Failure
Is Q504’s drain waveform ok?
Check and replace it.
No
Check and replace AFC input line
from T501 to IC401’s Pin 12. :
C408, R406.
Yes
Are D515, L501, Q504 ok?
No
Yes
Check and replace it.
Are D403, D408, D409, Q402
and Q411, Q412 ok?
No
Yes
Is 53 V on C623?
Refer to 6-2-1 No Power.
No
Yes
WAVEFORMS
13
Are D502, D503, R509, R510 ok?
Check and replace it.
No
Yes
Does B_Out duty of IC401’s
Pin 28 vary with different
H_frequency and image load
(Full White or No Video)?
Check and replace Q502, Q503,
IC401, T501
and REG_IN line to
IC401’s Pin 15.
No
Yes
Check and replace Q502, Q503,
IC401, T501.
12
14.0 V (IC401, #28)
CH1 P-P = 14.0 V
CH1 RMS = 7.34 V
13
136 V (Q504, Drain)
CH1 P-P = 136 V
CH1 RMS = 78.3 V
Symptoms 1: – No Power
– No Raster
– Unstable operation (Fixed FBT B+ voltage with different H_frequency,
Over 31 kHz: whistle sound, Narrow H_Size, Unsynchronized image, 31 kHz: OK)
12
Summary of Contents for DP14LT
Page 7: ...Memo 2 Product Specifications 2 4 DP14L DP15L ...
Page 9: ...Memo 3 Operating Instructions 3 2 DP14L DP15L ...
Page 13: ...Memo 4 Disassembly and Reassembly 4 4 DP14L DP15L ...
Page 44: ...DP14L DP15L 7 1 7 Exploded View and Parts List 7 1 DP14L ...
Page 45: ...7 Exploded View Parts List 7 2 DP14L DP15L 7 2 DP15L ...
Page 46: ...DP14L DP15L 7 3 7 1 1 Front Cover CRT Ass y DP14L ...
Page 47: ...7 1 2 Chassis Stand Ass y DP14L 7 Exploded View Parts List 7 4 DP14L DP15L ...
Page 48: ...7 1 3 Rear Cover Ass y DP14L 7 Exploded View Parts List DP14L DP15L 7 5 ...
Page 49: ...7 Exploded View Parts List 7 6 DP14L DP15L 7 2 1 Front Cover CRT Ass y DP15L ...
Page 50: ...7 2 2 Chassis Stand Ass y DP15L 7 Exploded View Parts List DP14L DP15L 7 7 ...
Page 51: ...7 2 3 Rear Cover Ass y DP15L 7 Exploded View Parts List 7 8 DP14L DP15L ...
Page 63: ...8 Electrical Parts List 8 12 DP14L DP15L Memo ...
Page 65: ...Memo 9 Block Diagrams 9 2 DP14L DP15L ...
Page 67: ...11 1 DP14L DP15L MULTI MEDIA 11 Schematic Diagrams 11 1 Power Part Schematic Diagram ...
Page 69: ...11 Schematic Diagrams 11 3 DP14L DP15L 11 2 Micom Part Schematic Diagram ...
Page 71: ...11 Schematic Diagrams 11 5 DP14L DP15L TILT OPTION 11 3 HOR VER Part Schematic Diagram ...
Page 73: ...11 Schematic Diagrams 11 7 DP14L DP15L 15 ONLY 11 4 H_OUT Part Schematic Diagram ...
Page 75: ...11 Schematic Diagrams 11 9 DP14L DP15L 11 5 Video Part Schematic Diagram ...
Page 77: ...Memo 11 Schematic Diagrams 11 11 DP14L DP15L ...
Page 78: ...Samsung Electronics Co Ltd April 1999 Printed in Korea Code No BH68 00128A ...