Samsung CL21K40MQGXXAZ Service Manual page 42

Troubleshooting
6-4-2 Troubleshooting Deflection Block
■ Countermeasures by Deflection Types
Countermeasures by Deflection Types
1. The screen is blank and only the relay repeats close and open when turning the power on.
This happens when the vertical voltage or vertical signal is not supplied, and because the Micom operates for 5 to 10 seconds and
then turns the power off by force as it cannot detect the vertical signal.
2. CHECK POINT
- Check that the vertical output voltage is measured in the FBT terminal.
VCC (+) : +16.5v
VCC (-) : -16.5V
If you cannot measure the output voltage, check that the collector voltage of the horizontal TR is 1360V.
If the voltage is measured, the problem is a defect in the FBT unit.
(When you don't have an oscilloscope, and you can hear the high-voltage sound, you can determine that the horizontal TR is
normal.)
Is the vertical input waveform output from the TDA9377PS/N3/A VDP Pin.
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