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Discussion Starter · #1 · (Edited)
It seems my 57" Sony (KP-57WS510) is starting to have convergence problems on the initial power on. It will correct itself after 30 mins or so but I have decided to attempt a IC chip repair. After reading many posts and searching for replacement IC chips, It seems that the Sanyo original OEM IC chips (STK392-560, and STK392-570) are hard to find anymore.

If I order from the recommended distributors lists, are the replacement chips considered reliable?

Can you recommend a replacement vendor (Mitsubishi, MCM, Mass Intergated, etc) on these chips since the Sanyos do not seem to be available anymore.

Should I consider ordering the STK392-570 (for higher heat) vs the STK392-560 for my repair ?

Thanks much to all who contribute here. I am a newbie to electronics repair but have learned so much in the last few days.

Thanks
Ken
 

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Either the -560 or -570 will work fine. As for the reliability of the ICs, I recommended certain vendors because they have been reliable. The quality of ICs varies unpredictably, but these vendors are some of the most diligent I know of about finding the best sources. Talk to them and ask them about why you should trust their parts over others.
 

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Your post has been moved to a more appropriate location to make information easier to find and to make it more likely that others who are interested will find your post.
 

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Discussion Starter · #4 · (Edited)
WhoHoo. I was able to successfully replace the IC chips. All is well again.

Thanks Leonard for your reply, your very informative stickies, and all your contributions to this forum. I cannot thank you enough.

I purchased the STK392-570 chips from electronica per the recommended distributors list.

Question: Is there any reason to clean the unit while it is open? I am usually a firm believer of "Don't fix it if it is not broken" but I really, really want to wipe a micro-fiber cloth over the RGB lenses and mirror. Is this a bad idea. I also want to close it up and be done with. Is there risk that something else might break if I do not clean it. What about hitting it with some compressed air?

Thoughts? Suggestions ?
 

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Discussion Starter · #5 · (Edited)
I wanted to also share a few experiences of mine to help others that might be brave enough to attempt this repair. Again, I was a newbie and a computer tech but had never done anything of this caliber. I was way out of my comfort zone.

Steve's Thread on "Steve's KP57WS510 Project" was very helpful with photos and info (If I would have initially known he was so close to me - Lincoln to Omaha Nebraska, I might have recruited him. I did not notice his locale until now.) Thanks Steve.

On removing the D board that contains the STK chips:
I had difficultly trying to determine how to disconnect the wires from the flyback transformer (FBT) to remove the board. After much research. It appears you are not to remove any wires from the FBT but from the components that feed from the FBT. I think it is called the focus wire (larger wire) that runs from the FBT to the HV Block and the secondary (smaller) wire from the FBT that runs to the front of the TV. The focus wire can be removed from the HV Block by pushing in and turning. Do not attempt to remove wires from the FBT. Experts, please correct if this is the incorrect procedure.

Pay attention to the multiple sets of 3 connections (RedGreenBlue) upon disconnect. Label these. I did not do this and when I disconnected and when I reconnected I had issues with my colors not lining up and initially thought my repair did not work. This is very important.

Desoldering Chips from Board:
The $12 desoldering tool from RadioShack was well worth the money in my opinion. It helped me make quick work of this task and helped again when I screwed up solders in future tasks.

Removing the STK chips from the heatsinks:
I had a hell of time getting these off. After some research, I found suggestions to use a hair dryer to help loosen. Also to use rubbing alcohol. I tried the hair dryer first and then the RA. I am not sure if it was a combo or the RA but it worked.

Soldering the chip pins to the board:
It seems my eyesight is not what is used to be. I quickly determined that I would need some help. So I went to bed and the next day went to my local Harbor Freight store and bought a $2.99 Helping Hand Magnifying Glass and a HeadLamp Flashlight for a few dollars. They are not the highest quality tools but it was what I needed to get the job done.


Hope this helps.
Good luck.

Ken
 

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I never even removed the anode leads from the focus block on these. Those connections are easy to damage, and if you break a tab on one you have significantly complicated the repair, not to mention that not getting them seated properly can be very dangerous.

For removing the chips stuck to the heat sink, I just use a screwdriver and a hammer and tap from the side on the defective chip and they pop off. If you have one that is really stuck, a wide sharp blade inserted under the edge and a tap does it. Be careful not to damage the heat sink and if you do smooth it out before reinstalling ICs.

Good advice Ken W.
 

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Discussion Starter · #7 ·
Leonard can you elaborate on what is the recommended way to remove the board from the Flyback Transformer or from the wires that are connected to the FBT? Can the FBT be removed from the board ?
 

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You don't need to remove it at all to do a convergence repair. Just turn the board on its side with all of the connectors removed except the anode leads. If you want to remove the lead from the anode splitter, push and turn about 90 degrees. If it does not release try again until it does but never pull very hard.
 

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Hi Ken (neighbor!), Congrats on the repair! :T

I haven't had any play time lately due to mega-overtime at work so I haven't been working on these sets lately but I'm pleased my write ups were of help to you. Things are supposed to let up though so I'm looking forward to another project or two soon.

I did take a crack at a LCD TV the other day - it would come on and then the picture would go away but if you held a flashlight to the screen the picture was there. Turned out those caps in the power supply aren't supposed to be swelled up like ticks! Replaced them and it's up and running! :bigsmile:

Removing the hv wires on these Sonys . . . for me it was a lesser of two evils. I just didn't relish trying to balance the board while working on it, trying to keep solder from rolling down the board (I don't do this every day) along with trying to keep track of my soldering iron . . . I just KNEW it would flop out of it's holder and melt the carpet! I prefer to just remove board and then sit comfortably in my plush and incredibly well lit electronic service area (i.e. the kitchen table). The risk of damaging the cables removing them was acceptable to me (it's really pretty easy to remove them - I'm getting bolder too as I've scrapped a couple of these sets now so I have some extra ends to solder on if I do booger one up :sweat: ).

Congrats again on your successful repair!

Take care,

Steve
 

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WhoHoo. I was able to successfully replace the IC chips. All is well again.

Thanks Leonard for your reply, your very informative stickies, and all your contributions to this forum. I cannot thank you enough.

I purchased the STK392-570 chips from electronica per the recommended distributors list.

Question: Is there any reason to clean the unit while it is open? I am usually a firm believer of "Don't fix it if it is not broken" but I really, really want to wipe a micro-fiber cloth over the RGB lenses and mirror. Is this a bad idea. I also want to close it up and be done with. Is there risk that something else might break if I do not clean it. What about hitting it with some compressed air?

Thoughts? Suggestions ?
At this age it probably needs a cleaning. Just be very careful. Sprayway cleaner is cheap and pretty safe.
 
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