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Equipment Repairs => PLASMA TV forum => Topic started by: KMpuggy on March 24, 2011,05:49:10

Title: SAMSUNG PS42Q96HD 42" Plasma TV
Post by: KMpuggy on March 24, 2011,05:49:10

Hi people, wondering if anyone can help me out as im at a dead end.


I picked up a 42' samsung plasma telly cheap knowing that it had a dodgy psu, clicking when you turn it on and i was expecting blown capacitors. But nothings never that simple with me. Turns out the caps are fine and one of the the Mosfets had blown. So i re-soldered it back on, replaced the fuse, turned it back on and the other Mosfet next to it went bang. These are not a problem as i can source them parts. Its ive noticed that an smd transistor?? has blown, got a chunk missing out of it. I dont know if this blew first time around, or when number 2 mosfet went pop as its on the same circuit as the one. Now that is the problem as i cant source that part. Stamped on it (B3J1) which means nothing when i search for one. How do i source the right part or identify it to get another one?

They do do a kit for this telly, works out £30, but even if i brought that kit it still might not work as there might be an underlying problem thats caused the problems in the first place, place i only want that little transistor. The last resort would be to send the board off and get it repaired. (£65) The 2 Mosfets can be brought for next to nothing, (fqpf9n50c) and its just that smd thats holding me back, so it would work out less than a fiver in total if i can get hold of the parts, and if it dont work, then just a fiver wasted.

One of these little 3 pin things, how do i know which one it is as there are so many out there?

(http://img-europe.electrocomponents.com/images/SOT23-03.jpg)


Here is some pictures of the board...

The B3 on the chip is wrote length ways along it, and the J1 is wrote across it. Its the same as the one at the top of the pic.

You can see where i un-soldered it, (Red arrow)

And you can see where the Mosfet went, damage has been done to the circuit from where it blew. (White arrow)

http://i5.photobucket.com/albums/y156/KMPUG/DSCF0990-1.jpg

Any help would be much appreciated.

Cheers

Title: Re: SAMSUNG PS42Q96HD 42" Plasma TV
Post by: watteau on March 24, 2011,08:47:50

Hello,
B3 (DX804) is a diode, unfortunately, there's no manual on the power-supply PCB from Samsung.
I've attached a .RAR (you'll need WINRAR to extract it) file containing a listing of SMDs that might be helpful.
Regards
John

P.S. also added the extracted .DOC

Title: Re: SAMSUNG PS42Q96HD 42" Plasma TV
Post by: KMpuggy on March 27, 2011,15:26:56

Thanks for that, i gave up in the end and went and paid £30 for the kit., sorted, well sort of.