Ps-50q96hd That went pop

[smiddy1980]

Hello, I am just starting to learn electronics and my first job was a 50 inch Samsung that was not working, every time I plugged it in it blew a fuse !!, there was a short on the board, I got a replacement for 25 quid, no bad as I thought I had cracked it !!! wrong, when I plug in now I get the click of the power supply but no picture and if I press the on/off button nothing happens, after a few min I noticed that there was smoke coming from the top IC on the buffer board, I pulled the power looks like a short, question is can this be fixed or is it a ne yboard and buffer board ? NOTHING EVER EASY

[tom66]

Re: Ps-50q96hd That went pop

The Y-main board is repairable with a reasonable soldering iron by hand. Y-buffer usually requires good skills to repair.

[smiddy1980]

Re: Ps-50q96hd That went pop

When powered up the ysus board has a green light and there is a light bussing sound, is there any where is can check for voltage on the ysus board as I think it ok and it may just the top buffer board and I may just buy one, but I am a tad scared in case it blows the new buffer board, ohh the dilemmas

[tom66]

Re: Ps-50q96hd That went pop

No, on these when the buffer blows the Y-main is almost always at fault. The LED lit on the Y-main indicates a protection fault.

[smiddy1980]

Re: Ps-50q96hd That went pop

so what's your thoughts, new yboard and top and bottom buffer? thanks for the reply by the way !!

[tom66]

Re: Ps-50q96hd That went pop

Y-main + upper Y-buffer
That being said, I think these older panels aren't really worth fixing, given the mediocre picture quality and often they have "sparklies" (pixels mis-firing randomly)

[smiddy1980]

Re: Ps-50q96hd That went pop

thanks for you input

[smiddy1980]

Re: Ps-50q96hd That went pop

I think I will give fixing the y board a shot, All the caps look ok but there are a few mosfets shorting in circuit on the 2 outer pins Gate and source? I am sure this is not right, I will get them out a test on the bench, there looks to be about 5 faulty, is this what you would see when the y main goes

[Clydeuk]

Re: Ps-50q96hd That went pop

Test them out of circuit if you can to confirm. I would also suggest replacing the drive i.c that supplies these if they have failed. Check capacitors in the PSU as well, I expect the PS you got was a pull, and check carefully the PS for dry solder joints, these are notorious for it. You will need a buffer as well or the Y main will fail again straight away, but there is always a danger that you miss something when repairing the Y main and take out the buffer again.

Not a fan of board changing but the general accepted repair on these seems to be to replace all 3 at the same time.

[smiddy1980]

Re: Ps-50q96hd That went pop

Anybody know where I can get a drawing of the ymain and also the best place to get the mosfets?

[tom66]

Re: Ps-50q96hd That went pop

No schematics of Y-main for this I'm afraid.

[Clydeuk]

Re: Ps-50q96hd That went pop

From previously working in an LG/Samsung service centre the manufacturer considers the Y Main a replaceable assembly and doesn't provide any schematics. For these older plasma sets they even priced the whole PDP including boards (apart from the PS) to be pretty much as cheap as replacing the boards, which for us handling extended warranty repair was always the method used with no risk of another failure. Panasonic did things differently and did have schematics, though board replacement was still the recommended solution. The Panasonic PDP's also came as just a bare panel.

I very much doubt you will find a schematic for a Samsung board.

[tw2005]

Re: Ps-50q96hd That went pop

Anybody know where I can get a drawing of the ymain and also the best place to get the mosfets?

I got mine off Fleabay, should get heaps of hits, 88N30W FETs I'm guessing since form memory there's a bank of 5,

I got mine from china but here's a UK search

http://www.ebay.co.uk/sch/i.html?_fr...c&LH_PrefLoc=1

i've got one of these now, Ymain on this is blown worse than what I've done, not just those large FETs, SMD stuff too

Don't have a problem doing the PSu repair or ymain but the buffers? might have a go at hand soldering the iCs, like tom said, it's not a favourite TV so hard to justify too many $. It's ok, I just like the panasonics but still it's not a bad Tv just my preference.

I enjoy fixing too much so I probably will have a go at some point. good experience.

[smiddy1980]

Re: Ps-50q96hd That went pop

cheers guy, well I'm just new to the old electronic repair so I will just give it a go with the ysus, even if I can get it to power on without the green light than I must be doing something right, use this TV as a practise, Thanks guys

[smiddy1980]

Re: Ps-50q96hd That went pop

Right guys, I got a repair kit with all the fets, caps and zdione, changed them all out and the TV is now switching on yeha....... I left the top buffer board out as I knew that one was bad, but when the TV is on I get the bottom of the screen is all fuzzy, is this because I don't have the top buffer in or is my ysus board still bad ?

[tom66]

Re: Ps-50q96hd That went pop

Can you show us a picture of the fuzzyness?

[smiddy1980]

Re: Ps-50q96hd That went pop

yes will post one just now

[smiddy1980]

Re: Ps-50q96hd That went pop

not sure how to upload pics but here is a link


http://server.pspcs.co.uk/ftp/fuzzy.jpg

[smiddy1980]

Re: Ps-50q96hd That went pop

I just read a post saying that if I don't have the top buffer in the bottom buffer wont know what to do and will show fuzzy pic? I don't want to spend £60 on a buffer if my ysus is still bad, but no green light and switches on and off now, so much better that it was

[smiddy1980]

Re: Ps-50q96hd That went pop

Guys need your help here, I bought a top buffer, installed it and I now get a funny fuzzy redish picture, can you point me in what I should be looking at now, I don't know how to upload pic on here yet but here is a link to them on my server

http://server.pspcs.co.uk/tv