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Old 11-01-2007, 03:56 AM
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dr.ido dr.ido is offline
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Join Date: Mar 2005
Location: SE Melbourne, Australia
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The view after removing the 30 or so screws holding it together. It was manufactured in 2002. Judging by stripped screws posts and the texta marks on almost every board it has been repaired several times in it's 5 year life.

The small board at the top of the picture is carries the standby power supply and the audio amplifier.

The panel itself is made by Chungwhua. Most of the other components are known brands (Rubycon capacitors, etc). That kind of surprised me at first considering the kinds of off brand and left over parts I'm used to seeing in a lot of recent cheap electronics, but I guess that can't get away with the kind of shorts cuts I see in cheap CRT TVs/DVD players/etc here.




The signal board which provides VGA and DVI inputs and the daughter card which adds composite and component video inputs. The only BGA IC in the unit is on this card. There is a space and connector for another card, probably a TV tuner.



The X scanning board. It's mainly through hole components and loads of surface mount diodes. Some of the diodes have already been replaced in a previous repair.



The Y scanning board. More of the same. No visible repairs on this board.



The driver (?) board. A stack of FPGAs, buffers and some RAM. I'm guessing that in a brand name display they'd probably use some custom ICs here. One of the surface mount capacitors had already been replaced with a through hole part.



The power largely obscured by it's heat sink. This is all through hole bar one tiny module. I found 2 bad capacitors (1500uF/200V) here that appear to be filtering the 175VDC rail that drives the panel. I don't know if this is the cause of the red snow yet, I don't have any suitable replacements on hand. I have seen bad filter capacitors that measured okay cause snow in CRT sets before.

All in all it looks like plasmas are more repairable than I thought, though this may not apply to other brands/models. I'm going to replace the bad capacitors to see if the picture improves, but considering the damaged panel I won't be spending any more time/money on it otherwise. If the panel was okay I'd look into it further. If I knew exactly what I was looking at I could handle working on the power supply and scan boards. Someone with greater skill and a finer soldering iron than I have could work on the driver and signal boards (with the exception of the lone BGA IC).
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