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Go to cover page
5. Troubleshooting (continued)
5.7Checking the interface circuit of sync signal
5.7.1Checking the control circuit of horizontal sync pulse
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| 1. | Video cable is defected. |
Check the horizontal |
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| 2. | Printed wire is broken between P304 pin13 and I314 pin46. | ||||
sync signal on I314 pin46 |
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| 3. | FB305, R364, R363 is open. | |||
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TTL level |
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| 4. | R371, C336, D305 is short. | ||||
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| 5. | I311 is defected. |
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| OK |
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Proceed to “5.8 Checking the |
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resolution change IC movement” |
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section |
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5.7.2 Checking the control circuit of vertical sync pulse
Check the vertical sync
signal on I314 pin47 TTL level
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| 1. | Video cable is defected. |
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| 2. | Printed wire is broken between P314 pin14 and I314 pin47. |
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| 3. | FB306, R368, R369 is open or more than one component. |
NG |
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| 4. | R370, C335, D303 is short. | |
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| 5. | I311 is defected. |
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OK
Proceed to “5.8 Checking the resolution
change IC movement” section
