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lcaillo,

Wow!! Thanks for the wealth of knowledge and for the parts distributors you provided in this forum.

Could you, please, answer a couple of questions regarding the infamous STK IC's?

First, i have a Panasonic 51" HDTV 1080i Rear Projection TV, Model No.: PT-51HX42F.
STK392-110 IC's. The blue convergence is out so I've been doing my homework to find the best way and the best parts to use to fix the issue.

Based on your recommendation i'm use the Hitachi STK394-160. I know in your posts you say tritronicsinc sells the Hitachi STK394 but i did a search on their website and could not find the STK394-160 IC in ANY brand on their site. Any ideas here?? I might try calling tomorrow.

So far the only place i can find an actual Hitachi STK394-160 from Vance Baldwin. Their description says its a Hitachi Hybrid Ic (Stk394-160e). I'm not exactly sure what "hybrid" indicates here. But its listed for $37.65 which sounds a little high or is that about right?

I also found a Sanyo STK394-160 on prelcoparts. Is the Sanyo IC OK?
AND they offer two models: STK394-160E and a STK394-160KT (says its a universl kit??). other than one being what looks to be a kit is there much of a difference here?

I appreciate any input and assistance.
Thanks a bunch.
 

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Tritronics sells the part only in the Hitachi kits. I only buy them in the Hitachi kits. Sanyo is the OEM for all STK parts. They made the STK394-160 specifically for Hitachi to replace the 392 series chips in their sets. They happen to work to replace the same parts in many other products. The problem with buyniung the parts outside of the Hitachi supply chain is taht you may be getting second quality parts or counterfeits. It is very difficult for distributors to know the actual source of the parts and reputable vendors, and many servicersa dn consumers have been burned by bad parts in the past. Prelco has generally been a good supplier but they are not one that I know very well.
 
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lcaillo,

Thank for the reply. I called Tritronics and they do have the STK394-160. I did ask if it is a Kit and he indicated it is NOT a kit just the IC by itself.

After reading through countless forum posts (especially yours) i found that in some cases others are also replacing the resistors and some are not (if they dont have a kit).

Since I'm going to the trouble of replacing the Convergence IC's do you recommend I go ahead and order replacment resistors? I gave the system board, capacitors, resistors, etc., a good visual look-over, everything looks good. I see nothing bulging, burnt or broke, although, I understand just b/c i cant see it doesn't mean its not bad. I would rather not replace just the two IC's only to find the possiblity of a bad resitor(s) as i realize a bad resistor could affect the new Convergence IC's.

ok, i'm newb here so i apologize of my ignorance. I know there are probably about 15 (give or take a couple) resistors right near both Convergence IC's. Is it safe to say the resistors are indicated on the PCB to which resistor works in conjuction with the Convergence iC's? If not, how do i know which to replace?

If you do recommend replacing the resistors what are your recommendations here? Brand, uprades to stock, etc? I figured i would order them from Tritronics too.

Also, with your expertice would you happen to know the part numbers to them ( i realize not all TVs are the same)? I was hoping that the typical resistor with the Convergence IC's are the same. i'm currently at work and would have to wait until this evening to get a visual of one - I realize thats probably the safest bet. I can use your color code charts you provided for help too.

Again, thanks for your help and any input.
 
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BTW - I've read where others (including myself) are having problems searching for: STK394-160 on Tritronics website. The search comes up empty.

I called Tritronics and got the stock #: CZ01341
Enter the stock# in the search and that pulls up the IC.
 
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lcaillo,

One other question. The Tritronics guy said the CZ01341 is an Hitachi. However, the their site says Manufacturer: HYBRID IC (STK394-160E). I just want to verify the "Hybrid" is OK?? Can i take a stab and say a Hybrid of Sanyo??

Thank again.
 

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All of the chips should be Sanyo parts. They are all hybrid type ICs. You are taking a chance if you do not buy them under Hitachi part numbers. Buying them in the kits from Hitachi has been cheaper in the past.
 
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Since I'm going to the trouble of replacing the Convergence IC's do you recommend I go ahead and replace the resistors too? I gave the system board, capacitors, resistors, etc., a good visual look-over, everything looks good. I would rather not replace just the two IC's only to find the possiblity of a bad resitor(s) as i realize a bad resistor could affect the new Convergence IC's. Besides the blue convergence being bad i also have a slight vertical bow on the right side of the screen. I seem to have read that might be due to bad resistors??

ok, i'm newb here so i apologize of my ignorance. But, i'm not exactly sure which resistors work in conjunction with the Convergence IC's. I know there are about 12 resistors right next to both Convergence IC's. The are staggered and some have different labels: 2.2ΩJ, 82ΩJ and 120ΩJ. Based on what i've read i believe its supposed to be the 2.2ΩJ resistors.

OR

There are also two other nearby resistors that have a label on the PCB that says CONV-18V and CONV+18V. I dont suppose the CONV relates to "Convergence"??

Again, i apologize for my ignorance but i'm also grateful for your help.
 

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All of the resistors should be checked with the chips removed and the convergence yoke connectors removed. The low ohm values are the ones that usually fail, but check ALL of the large resistors near the heat sinks that stand up off of the board. Replace any that are discolored or not the right value.
 
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Great! Thanks lcaillo,

I'm going to go ahead and order the 2.2ΩJ which many seem to replace as well. I figure its only 6 resistors and it might be a good idea since i'll have it torn apart.

I tried to see all the information on the 2.2ΩJ resistors but its difficult to read without removing the entire board and I didnt want to do that until i have all the parts.

I've read on forums its a 2.2ΩJ 1W AND 2.2ΩJ 2W for the Panasonic. I figured I would ask the expert. With your experience can advise the wattage please (I'm hoping the Convergence IC Resistors are the same for most TV's)? If nothing else i'll order both. both are cheap.

Thanks a BUNCH.
 

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STOP!

You must verify the values FOR YOUR MODEL! Do not assume that all Panasonics or other brands all use the same parts. You have to check by reading the value printed on the part, or using the color codes, or checking the service manual. Do not trust generic information that you get on the forums! Check the manual or the parts themselves to be sure.
 
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lcaillo,

I just want to give a big "thank you" for your assistance. After reading through countless threads (especially this one), watching youtube videos on desoldering and proper soldering, reading up on any related information in replacing IC chips etc., I have successfully replaced both IC Convergence chips and the (6) related resistors. My Panasonic is absolutely 100% BEAUTIFUL. I had absolutely NO problems (none). It’s like having a new TV again. Its great to be able to watch HD in 1080i again.

Probably, the biggest issue(s) I read on most threads was poor soldering work. I made sure I took my time and checked, rechecked, triple checked, quadruple checked my solder points. I even took close up pics of all my solder work with my digital camera and blew the pics up on my computer monitor to examine them even further. All solder points are perfect.

I must say I was very nervous and yet optimistic having done my homework. I know there is little room for error and that I could seriously do more damage if I wasnt careful. In the end I am proud of what I accomplished.

Again, thank you for your help and thank you for your wealth of knowledge.
 
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