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Discussion Starter #1
Hello,
I have 62 in Phillips wide screen the picture comes on and after a few minutes it turns into three pics. When I turn it off and it goes back to normal for a few minutes, don't know whats wrong with it. Can anyone help me with this problem?

Thanx for any help in advance.
 

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A little more descriptive info would help . . . I'm guessing you mean the picture looks 3-d and there seems to be three pictures with red/blue/green halos and the such?

If so it's probably the STK convergence chips and there's a ton of information on that on the forum, just look around a bit.

Hope that helps, if the picture is doing soemthing else maybe you can take a picture and post it for us . . . a picture is worth a thousand words!

Take Care,

Steve
 

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Discussion Starter #3
Yes it looks 3-D. Is that the convergence? How difficult is it to replace this on the this on Phillips?
 

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Please post your model number as that will help those trying to help you.

Also, Leonard has made a series of really nice articles that help you understand all of this and what it takes to attempt a repair.

For the convergence the articles are here, please read them all . . .
http://www.hometheatershack.com/forums/diy-repair-maintenance/5600-crt-based-rptv-convergence-repairs.html

How hard is it? Like many things in life, it depends . . .

I've only done two of these and helped someone do a third, so I'm far from an expert, or even "experienced" by any stretch of the imagination!

That being said, this is what I've done . . .

*) Hit the net and look for a service manual, I've not failed yet to find one - even one for an obscure Hyundai unit I helped a friend fix.

*) Get your model number and hit the net and see what you can dig up. You may luck out and find a good thread on your specifc set - we did on my son's Magnavox, it even had pictures!

*) Usually the chips are bad and sometimes some supporting resistors and maybe some fuses. Again, hit the net and see if someone has the board part numbers and values listed for you. If you have an accurate meter you can lift one leg of the resistor and read it's value but resistors are cheap and if I'm going to the effort to lift one side I've just preferred to replace them with new ones.

*) Only buy replacement parts from well respected suppliers - Leonard has thoughtfully supplied a list for us. I've dealt with Acme twice now and couldn't be happier - good parts and lightening fast delivery, as well as very good pricing (remember, these are original parts and not Chinese knockoffs!).

*) Once I've done the research and got my parts I like to take the unit outside, remove the back, and blow the dust off the boards. Now don't be stupid here, don't blast the thing willy nilly with high pressure air as you could dislodge a cable or something. Pay attention to where you're directing the air and use a reasonable pressure (I have a blow gun with a variable trigger so I can vary my pressure easily). A shop vac may be a better idea.

*) OK, once that's done I take it back in and then take some digital pictures for reference.

*) Then I look for the board with the convergence chips - it's easy to spot, the chips are HUGE! Look on the net for pics of STK chips and their heat sinks.

*) Now I use some masking tape and I start at the edge of the board and label the closest wire. I label the wire, use a permanent magic marker to put a mark on the left or front side of the connector (depending upon the orientation of it), and write the number on the circuit board by the connector. I use a Sharpie permanent marker with a very fine tip and I make sure not to cover up any board markings when I do it. Then I carefully unhook that cable. Repeat that as needed until they are all unhooked.

*) Next I look for screws and latches. Usually the boards are on a plastic grid tray thing and there's four or so screws holding it down t that tray - usually near the front, back, left, and right sides of the board. Remove the screws and then look and see if there are any plastic latches holding the board down, if so just push 'em over while you pull the board up.

*) The board should come out now and you can take it to your nice comfy work bench to work on it.

*) Note - You'll see some references to leaving the board in the unit and just raising the entire board tray assembly into the "service position". Doing this would have the advantage of not having to unhook all the cables but I don't like to desolder/solder vertically. I can just see me getting too much solder on a connection and a bead rolling down the board and bridging who knows what! I suppose though you could stick some duct tape or something around where you're working so if a bit of errant solder got loose it would be directed away from the board. My other concern is pulling a wire loose or something though - which could be a booger if you haven't looked at them all and labeled them all. I'm sure service people do this all the time though, so it may be easier than it's appearing to me . . . you'll justhave to decide what you're comfortable with.

*) Now you will need to remove the chips, resistors, fuses, etc.. Radio Shack sells a soldering iron with a desoldering bulb permanently attached to it for about $12 and it works fine, get one! Just depress the bulb, warm up the connection, and release the bulb and it'll suck the solder right out of that hole for ya.

*) Once the chips are desoldered you can unbolt them from the heat sink or sometimes they have a clip. Whatever, remove the mounting hardware. Now gently pry on the chip and it should break loose from the heatsink (it's got grease between it and the heatsink that's probably glueing it down). The chips should come out now, though you may have to warm a solder joint or two up to get it to let go (be gentle, don't rip the chips out or you may damage the solder pads!).

*) Use some alcohol and clean the old heat sink grease off the heat sink.

*) Desolder and replace any resistors, fuses, etc..

*) Apply some heat sink grease to one of the STK chips. I think about any heat sink grease would be OK, but I work on PCs a lot so I've always got some Arctic Silver on hand so I use it. Carefully and gently replace the STK chip. Make sure the legs are all in their holes, then reattach it to it's heat sink. This is great as it holds the thing while you are soldering it - so solder it up now! Be carefull, don't overheat the board and don't create any solder bridges. Don't be spooked, these boards have a fair amount of room and are pretty easy to work on. Now, repeat that for the other chip.

*) Once the defective components have been replaced then reinstallation is just the reverse of disassembly.

*) Once it's reassembled you probably need to clean the mirror and lenses as you probably blew dust up on them when you were cleaning the unit up.

*) Once it fires up you will have to adjust the convergence - read your manual on how to do that.

Now a few other tidbits . . .

There are several variations of these chips and a lot of times there's an upgrade chip that may work better. I prefer to do this if it's available. Others are staunch supporters of replacing with exactly what was in the unit to start with. Hard to argue with that as it eliminates the compatibility question and the stock chips probably lasted several years so the replacements probably will too. Upgraded chips will probably just got a bit longer.

There's a couple places selling kits that contain all the parts you need, a copy of the service manual, a set of pictorial instructions based on your set, and best of all - the right to phone consultation if you have problems. They run about $20 or so more than getting a free manual off the net and ordering your own parts but the phone consultation help in the event of problems is probably worth every bit of the little extra if you end up needing that help. The only real downside is that they usually only have exact replacement parts in the kits, no upgraded parts. One such company that seems to have a good reputation is www.tvrepairkits.com (I'm in no way affiliated with them, nor have I even been a customer. I've just read a bunch of comments by customers on the various forums).

If you haven't soldered much then while you're at Radio Shack buying your desoldering iron buy some ic sockets and a solder ring perf board, then go home and practice soldering / desoldering on it. Soldering isn't that hard so you should pick up on it pretty quickly.

That's about all I can think of, hope it helps!

Leonard . . . wherever I screwed up PLEASE correct me!

Take Care,

Steve
 

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I had a chip go bad on my original Philips 50 inch plasma. Hoped for a courtesy fix or even information from the company. Found them not very supportive even though You tube was filled with videos describing the "half screen" issue. Lugged it to a repair shop...heaviest thing to move. Probably a cheap fix but I paid $300 and all has been well since.
 

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It would be helpful to others to have a model number and more information about the actual problem. It is always best to start a new thread to discuss a different issue and include the model in the thread title.
 
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