Samsung DV7720KV Service Manual page 26

Troubleshooting
6-2 Blue background not shown (LD,CD)
Check for 4fsc signal
at TP1
Check for Video signal
at pin 78 of VIC2
Check for video signal
at NC6
Check for video signal
at pin 7of NIC4
Check for video signal
at pin7 of VIC10 on the
FMV PCB
Check for video signal
at emitter of NQ1,NQ2
Samsung Electronics
NO
YES
NO
YES
NO
YES
NO
YES
NO
YES
NO
Adjust VCTC1
Check for micom
interface
YES
Check for video signal
at base of VQ28
YES
Replace VQ28
Replace NIC4
Check TV mode:NTSC or PAL
Check for connection of VCW1
on the FMV PCB
Check for connection of VCW1 on the FMV PCB
Replace NQ1,NQ2
NO
Replace VX1
NO
Replace MIC101
NO
Check for video signal at
base of VQ25, VQ19
,VQ20,VQ21
6-2