Samsung HP-T5054

[gustav]

Got this from a craigslist ad for free. Yep. Just come by and pick it up. They said a "pop" happened and then it went out. Haven't opened the hood yet, but just wondering if anyone has some experience with this model before I do. This is my first Plasma and looking forward to working on one. It's a 2008 model.

This could be a cheap and easy fix or an expensive and complex one. But hey, its free.

Thanks

[kevinm34232]

Re: Samsung HP-T5054

Check this

https://www.badcaps.net/forum/showth...light=hp-t5054

Upper Y buffer and shorted transistors on Y-Main. Look for a damaged IC on the upper buffer, that's the most costly part of this repair, the FET's are cheap.

[capkid]

Re: Samsung HP-T5054

I wonder what the failure rate is on this particular model.

[kevinm34232]

Re: Samsung HP-T5054

I had one with just a bad cap and fuse and Y-main also right where the connector for the PS is.

[gustav]

Re: Samsung HP-T5054

Well, for a quick look before I get it set up, just like what Kevin posted. The upper left corner. I seen a few boards on e-bay for under 50. I really don't want to try to replace the ic/s maybe it's best to replace the board. This is just for starters. The y-main board has not been checked yet. I'll check on the prices on the ic's but a hot air station would also have to be ordered to replace them. I also assume the other i.c.'s are about to go, so replacing them might be in order. A "repairman" told them that it would be $400.00 to fix so they bought another set and gave this one to me for free.

Thanks to you all

[kevinm34232]

Re: Samsung HP-T5054

Also my buffer board was the same as yours (LJ92-01491A), I was able to replace with LJ92-01276C which I was told would work and it did.

[gustav]

Re: Samsung HP-T5054

Well, went out and ordered the Radio Shack 640053 solder station. I know it's not a weller or a Hakko, but for 40.00, I went for it. It doesn't look to bad for a hobbists. Anyways, I was wondering how to remove the y buffer ic without a hot air station safely. I have a heat gun, I know not the greatest method, but it's what I have. The problem I heard is ripping out the tracers when it gets to hot. Some has used the Kapton tape to help protect the other smd's, but there are three grounding "solder holes" in the middle of the chip I'm concerned about removing and replacing. A good you tube video shows the ic being replaced but doesn't do anything about replacing the bottom three holes with solder. I do have solder paste. I'm reluctant to buy a low priced hot air gun, for I don't want to invest anymore money into the project. I am open to buying one if it is highly recommended.

Any ideas would be helpful. I guess this week I'll go at it and see what is blown or shorted and start ordering parts.

Thanks

[capkid]

Re: Samsung HP-T5054

I know that retiredcaps has used a heat gun with kapton tape to remove the ICs. You can put a small amount of solder paste on the center of the pad for the replacement chip then use the heat gun on the underside of the board to melt the paste. I usually do that after I've soldered the pins onto the board.

[tom66]

Re: Samsung HP-T5054

You will probably need to remove the epoxy first (don't forget to replace it after putting new IC on, as it is used to insulate the pins, there is up to 200V between them.)

[trunkle]

Re: Samsung HP-T5054

there is a class action suit and you can get it fixed free.
http://www.ccl-la.com/blog/index.php...ower-supplies/

[tom66]

Re: Samsung HP-T5054

there is a class action suit and you can get it fixed free.
http://www.ccl-la.com/blog/index.php...ower-supplies/

Unrelated -- this is a different, although still common fault.

[gustav]

Re: Samsung HP-T5054

Finally, got it setup to start working on it. It appears to be the default issues with the t5054: Blown cap, and IC so far. I guess it would be advisable to go ahead and replace the five fets Q5500 (K2837), Q5304 (88n30w), Q5303 (88n30w), Q5302 (88n30w) and Q5306(88n30w).

Also, Maybe go ahead and get Q5501(B20nk50z) replaced. And of course the Cap c5709. The green fuse by that cap is also open. I having a hard time finding the parts unless I order from China. I thought for sure Digikey or Mousers would have at least the FETs. But no. Anyway, here is the pics and if you all see anything, please point it out.

[capkid]

Re: Samsung HP-T5054

You can get all the FETs on eBay. Specifically, I buy from SLP5188 on eBay - never had a problem with this seller in a dozen+ transactions, and he has all FETs (B20NK50Z, K2837, and 88N30W). Mouser or Digikey should have the fuse (vaguely remember purchasing the pico fuse from Mouser).

[gustav]

Re: Samsung HP-T5054

Yep, they're on Ebay as well as the buffer ic. fe3407. Would ordering 2 or more of them for backup? I heard you really just need the one that's blown, and others suggest replace them all. Also in the pic two, q5001, it appears one leg is discolored, indicating that q5001 is bad. Also, that stupid black pad. What is the easiest way to get it off and on again. Also the bottom of the buffer I.c. was different than I thought it was. Two "solder holes" are bridged. Is it important that they remain that way? or just fill up them up with abit of paste?

[capkid]

Re: Samsung HP-T5054

Yep, they're on Ebay as well as the buffer ic. fe3407. Would ordering 2 or more of them for backup? I heard you really just need the one that's blown, and others suggest replace them all. Also in the pic two, q5001, it appears one leg is discolored, indicating that q5001 is bad. Also, that stupid black pad. What is the easiest way to get it off and on again. Also the bottom of the buffer I.c. was different than I thought it was. Two "solder holes" are bridged. Is it important that they remain that way? or just fill up them up with abit of paste?

(1) Buy your FE3407 chips from US sellers only. There are some used chips out there that have been refurbished to look like new (mostly from China). Also, I only replaced the one bad chip, since the TV was old. I also added small heat sinks to the chips on both buffers to help with dissipating some of the heat. These Samsungs get very hot, since there are obviously no fans in them.

(2) Replace all the ICs on the same heat sink as Q5001 (Tom's recommendation).

(3) To remove the black bumper, I used a hair dryer (NOT A HEAT GUN) and slowly pried it off with my fingers. To put them back, heat the adhesive side with a hair dryer, immediately stick it back on the board then heat it again with the hair dryer while applying pressure.

(4) No, it's not important that the holes be filled or bridged. Put a small dab of paste on the front side of the pad, and it will melt and fill some of the holes.

I included some recommendations in kevinm34232's thread about how to replace the chip. I've done several myself.

[gustav]

Re: Samsung HP-T5054

Thanks capkid. It worked. Also, I was bidding on a hot air station for really cheap bid. Had a sniper at the last second outbid my highest automatic bid by .50. That's not right. There's no way they could have known what my limit was. Errrrrgh. I beginning to Really hate Ebay. Got so worked up I decided to try the heat gun approach with aluminum foil shaped like a cone to a point the size of a dime. Covered the connector with foil tape and applied the heat very carefully. I used the weight of the pick tool and did not force it at all. Got the chip off with no problem. So I thought. The pic shows what looks like the ground pin was burnt by the chip exploding. It's loose but still attached. My question is do I go ahead and use the board with it like that or just go get a new one. Seen a couple of them reasonably priced. I was going to order two or three of the ic chips in case one of them was blown again. But the difference between the new board and getting the two chips with silicone would be justified. Anyway, here's the pic. Also, ordered from Suburban Electronics for the FETS. Mouser and Digikey had some generic ones, priced the same.

Any thoughts on the board?

[capkid]

Re: Samsung HP-T5054

Yeah, I figured you might have some damage to the board; it's a bit of a crap shoot. I'd probably try attaching a chip, since it's only a ground pad. You could buy a used board, but there's no telling how long it will last.

Edit: With regard to eBay, I almost never play the auction game. I just look for a good "Buy-It-Now" deal, preferably with "Best Offer".

[gustav]

Re: Samsung HP-T5054

Looks like the parts will all be here thursday or friday. I wondering if using a soldering iron to use with that fe 3407 chip, or use the paste. I've used the paste once and it was a little frustrating since the thin line of paste covered the pin's end. But once it was lined up.
applied heat and done. checked for bridging, cleaned a few up. but nice. Haven't tried using the iron yet. Oh well. Got to someday. Just sitting here waiting for the parts to show up.

[capkid]

Re: Samsung HP-T5054

I don't like using paste on these chips, but it could work. I prefer to drag solder.

https://www.badcaps.net/forum/showpo...66&postcount=4

[gustav]

Re: Samsung HP-T5054

Just got done practicing with the paste. My soldering tips I forgot to order, thinking the locals would have something. Nada. So, looks like I will have to order some tips now. And that "third hand" to hold my magnifying glass while trying to solder. I can use the weller, and the hakko tips but I'm not sure which type of tip to get. So far, the paste with heat gun is weird. I guess the hot air gun would be the way to go. But if any solder gets underneath the arc of the pin, there might be a hidden bridge. With the soldering drag approach perhaps the solder would be limited to just the pad of the pin avoiding any bridging along the pin sides. Since I do have an old board with a smaller ic and some chips to play around with, and a 100 pin one to do my final test, I can get my confidence level up before jumping to the only fe3407 chip I bought.