TROUBLESHOOTING HINTS
1. No Character
No Character
Are the Contrast & | No | |
Brightness Controls in |
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OSD menu |
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Change the Contrast & Brightness control value to maximum
Is whole |
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screen bright? |
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| No Raster | ||
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Is CRT |
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| Check the peripheral circuit | ||||||||||||||
Cathode (Rk, Gk, Bk) |
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signal level |
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normal? |
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| No |
| About 30~35Vpp |
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Is the
output signal of theYes (pin 14, 16, 18) 
IC801, normal?
| No |
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Is 12V line | ||
normal? |
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Check the video output circuit and its ambient circuit
Trouble in 12V line of the Main PWB
Yes
Is blanking pulse (pin 20 of IC801)
normal?
Yes
Is input signal
normal?
Yes
Trouble in IC801 and
its ambient circuit
No
No
Check the clamping pulse circuit
Check the signal cable
15