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LG Studioworks 775N / EV7001 (CA-65) doesn't start

 
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the_ccm
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PostPosted: Mon Aug 22, 2005 7:01 pm    Post subject: LG Studioworks 775N / EV7001 (CA-65) doesn't start Reply with quote

Hi,


I've got a problem on a LG 775N monitor.

When I power-on the monitor, the power led goes on. A relay is clicking, I hear some noise as if the high-voltage is generated and then it stops. The relay is clicking and the power-cycle starts over again.


I check secondary voltages on SMPS, there is 4 lines : 75V, 160V, 6.3V and 15V. Everything seems to be ok except for 15V line which is only 11V , i thought one component were dead on the 15V line but couldn't find one ?? also on THT no -30V, -120V, -40V etc. also B+ transistor driver (IRF9530) is very hot after 30 seconds ......
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the_ccm
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PostPosted: Tue Aug 23, 2005 7:26 am    Post subject: Reply with quote

Ok maybe this will help :



when "DPMF Low" is low, V1 equals to 15V and V2 nearly 0V, which is normal. But when DPMF is 5V, V1=11,2V and V2=11V. Output current on transistor collector is 0.33A , but even if i cut all after transistor output, and i place a 100Ohm resistor for example (0.15A), V1 fall down to 11,8V ??? D924 and C925 have been changed without success .................

Thanks for your help
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PostPosted: Mon Aug 29, 2005 10:12 am    Post subject: I have same problem Reply with quote

Hi,

I Have same monitor too and also I have same problem too. Did you find any solution for this.

Thanks

Baris
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PostPosted: Sat Oct 15, 2005 8:08 am    Post subject: Reply with quote

check on crt bord their is any dry solder i found many time in 15 "
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Kulfi
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PostPosted: Wed May 31, 2006 6:47 pm    Post subject: Problem Reply with quote

Same Problem
did any one found any solution.
Thanks
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Guest






PostPosted: Tue Dec 25, 2007 5:08 pm    Post subject: Reply with quote

your FBT is gone. Change it
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PostPosted: Sun Sep 26, 2010 6:16 am    Post subject: Reply with quote

Same Problem
did any one found any solution.
Thanks
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