No Video - Samsung CHB5707L/5237L Service Manual

7-1-16 No Video

Check signal cable and connection.
IC101 Pins 5, 8 and 10 inputs
15
are right?
Yes
IC101 Pins 21, 24 and 26
16
outputs are right?
Yes
IC102 Pins 1, 3 and 5 outputs
17
are right?
Yes
Cathode DC levels are right?
Yes
G2 voltage is right?
Yes
Change CRT.
Done.
CHB5**7L/6**7L/7**7L
No
Check the signal cable connection.
No
2
Check I C bus and +12 V line.
No
Check +12 V line.
Check and replace IC102.
Check +75 V line.
No
Check and replace QR01, QR02,
QG01, QG02, QB01, QB02.
No
Check G2 wire, CRT Socket board,
and FBT.
7 Troubleshooting
WAVEFORMS
15 780 mV (IC101, #5, 8, 10)
CH1 P-P = 780 mV CH1 RMS = 2.494 V
16 2.72 V (IC101, #21,24,26)
CH1 P-P = 2.72 V CH1 RMS = 13.78 V
17 34.4 V (IC102, #1, 3, 5)
CH1 P-P = 34.4 V CH1 RMS = 44.52 V
7-9