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lg T420xw01 takes 1 hour before picture

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mohomane

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greets to all.i got lg lcd-42lg30r that has perfect sound,rm function and tube glowing at switch on,but no picture after an hour or more pic come perfectly.I changed all caps on pwr supply board but no win,i dont have the scheme pls help.:?:
 

LG_42LG30R_SM.

Regards
 

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  • LG_42LG30R_SM.rar
    3.7 MB · Views: 483

mohomane said:
greets to all.i got lg lcd-42lg30r that has perfect sound,rm function and tube glowing at switch on,but no picture after an hour or more pic come perfectly.I changed all caps on pwr supply board but no win,i dont have the scheme pls help.:?:
Click to expand...

Just turn on prior to one hour before use (LOL). No when cold turn it on and at the same time use hot air hair dryer and heat up some area and see if the picture comes fast this will get you to the problem area (roughly). One of the semi-conductor is behaving this way. Or when it is working you can freeze one by one semi-conductors such as ics to see if picture is gone one of the two methods should bring some results. There are freezers available in cans that can be sprayed with precision. And now I see you have a schematic too thanks to barakagsm.
 
I was going to take look at that schematic so I extracted the RAR file and converted to PDF for viewing and saw that I could not find the power supply circuit .
I suspicion that it is at the faaaaaaar right side of Adobe page 24, as that area seems to have the starting of a few related components showing.
Can anyone else see and / or confirm the PS area.
From your description I tend to suspicion CFL /driver or power supply.


73's de Edd
 

Try this,

lg_42lg30r_32r_ch_lp81a_[x]

42LG30R-djvu
 

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  • lg_42lg30r_32r_ch_lp81a_[x].pdf
    4.2 MB · Views: 542
  • 42LG30R_MA.djvu
    1.5 MB · Views: 90
hi,if power supply ok,heating & freezing dont solve, i suspect tcon board,but each tv has its own method of tcon testing.
 

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