: Hitachi & Other Manufacturers Convergence Problems (STK392-110 ICs) Read Post 1
I Have A Hitachi 43uwx10b That Recently Had A Convergence Problem-after Checking The Forum Here My Freind Replaced The Amps And Resistors That Burned Up And The Tv Was Back Working Again-at First I Was Getting A Green Tint To The Picture And The Bars On The Sides Of The Picture Seemed To Change From Grey To Green-after Some Fine Tuning And Setting Magic Focus The Picture Came In Clear And The Green Went Away-the Problem I'm Having Now Is There Are Three Vertical Lines At The Top Of The Screen.one Blue One Yellow And One Red(actually The Red Is Just A Small Smudge).it Looks As Though Someone Took Colored Markers And Scribbled These Lines On The Screen -any Idea What This Could Be From-it Looks As Though It May Be Something On The Lens-when I Disconnect The Cable And Have White Snow They Remain-any Help Would Be Appreciated-thank-gmg
2006-03-20, 06:35 AM
I have the same TV, and just repaired my convergence board per the instructions on here it worked perfectly for me. It did take me 3 times on adjusting the DCAM to get the screen back properly. did you try to move the vertical up a little in the settings. or you may have to go back into DCAM I had that same problem on the left side which I corrected on my third time by fine tunning and sliding the green out farther left then aligning the red and blue to it..
2006-04-07, 04:10 PM
I have a 43UWX10B with a bad red convergence amp. I have examined the set in order to determine if I want to replace it myself, but haven't found which board is the convergence board. I've had no luck finding any diagrams online which would point me in the right direction. Could anyone give me an idea of where I should be looking to find the convergence amps? I just want to get an idea of how accessible the board is to remove and also to determine how complex the replacement would be.
Thanks in advance
The board is very easy to access and remove. On my TV it was the one on the left side of the TV, when viewed from the front. If viewing from the back, it's on the right.
The convergence ICs are attached to a heat sink. The CRTs plug into the convergence board - make note of the proper positioning of the R,G,B.
There are several screws to remove and you need to remove/open the "jumpers" between this board and the one next to it.
As indicated earlier in this thread there may be more wrong than the ICs.
I strongly suggest you replace both ICs and all the resistors on the board (there are not many - 3-4 if I recall) and you should also check the board for continuity since some boards have cracked solder. You may need a service manual from Hitachi. You can order this - I paid about $30.
If you simply replace the ICs and there's still a fault in the board, the ICs will blow again either right away or very quickly.
You may wish to take the board to someone to do this service. Cost probably 2-3 hundred $ if he has no difficulty. The service person may have a service manual, or access to it.
Please put your location in your profile, it'll often help us help you.
Remember, there's high voltage in the TV, so don't electrocute yourself.
2006-04-07, 05:14 PM
The board was right in front of me all the time ;) . The amps are on the back sides of the heat sink, so I didn't see them at first. I was also expecting three STK392-110s. There are only two.
I will have to look closer for the resistors you are recommending I replace. There are 10 small resistors immediately in front of the amps and dozens on the entire board.
I suspect you can't predict the need to replace the resistors by visual inspection or by guaging the relative severity of the display distortion?
I'm sure the questions has been asked and answered many times (but I'll ask it here again), is the entire board available - and if so - what do you estimate the cost would be?
Thanks again for your help. This forum is a great resource. I really appreciate the information. If nothing more, I'm at least a much more educated consumer.
BTW: I will update my profile to provide more information.
The entire (rebuilt) board is available from Hitachi. I believe it's around US$300. I also believe they charge you US$75 "extra" if you don't return your board to them, hence the rebuilt boards...
The resistors are 3-4 resistors with numbers in the 50s on the circuit diagram if I recall. (something like RK-50, 54, 58...)
This is a great thread and this is the only place where I could find some useful information on rear projection convergence issues. Thanks a lot.
I have a 3 year old 43FDX15B and I am trying to fix the red lines that are appearing across the screen. I checked the board and only one resistor RK46 is little bit dark. Other than that everything looks OK. I do not know how to get the board out, neither do I know how to replace RK46 and STK392-120. Can someone send me step-by-step instructioon for replacing these two parts?
I wish I can upload the photos of my darker resistor and the pin that I was not able to pull out. I will figure out a way to do that.
Thanks a lot,
See post 44 for instructions on removing the board. Not sure if the F series is the same though, it may not be.
See the following for image posting.
Sometimes the resistors look fine, but are still bad.
2006-04-15, 03:06 PM
Just a side note that I had said before... I do service the Hitachi projection TV's and this has been talked about before but thought I would eloborate on something. Most all the projection models have a service bulletin that replaces the STK392-110 and 120 with the STK392-150 along with 6 resistors, two with each color. When I asked a engineer about this because I was curious why all the service manuals had the 150 IC's listed when the boards mostly had the 110's and 120's. Seems in production they kicked out the TV so quick supply was an issue so they used which ever they had access to and would use different resistors for the 110's or 120's. I will post here in a couple days the resistor values and locations and let you know which models this is for. Most all the 14G and 15 chassis call for the 150 when replacing.
2006-04-21, 01:12 AM
We have a Hitachi 53UWX10BA, and the Green will not adjust up and down. It seems to be the last problem. Any suggestions, I read that it could be some resistors? RK50 RK54 and RK58 does that sound right. Could you you desribe or send a picture of them if its. Any other idea?
2006-04-24, 02:58 PM
I have both a 43fdx01b and a 43uwx10b. The widescreen (UWX) was moved from a working location (in laws) to my basement. The blue gun bows inward severely at the top and bottom, the green shifts slightly to the upper left.
Gently tapping on the set fixes the problem. After reading this thread, I took out the conv board and looked at it. I can't seem to see any broken solder joints. I have not tested with a meter. I also can not see any burnt components. Using my finger to gently flex the board with the power on duplicates the problem or lack of problem.
Is it safe to assume this is a bad solder joint stressed due to moving the set, or do dying amps exhibit this behavior (tapping to temporarily fix the problem)?
I went ahead and adjusted the DCAM (I am an ISF) but hate to spend any more time on this unless I can fix it, as I am sure the problem will get worse.
I have also noticed that the menu screen (or stationary screens) are rather "jumpy". Paying close attention to the magic focus, it appears that the green gun is the one that is the worst.
"Tapping" worked with me for a few months too, but eventually I had to get the ICs replaced, the appropriate resistors replaced and the board resoldered.
My technician told me that the delay probably "worsened" the situation, but I'm not 100% sure about that because the board probably had cracked solder when I needed to start the tapping....
2006-04-24, 04:00 PM
I am considering just hitting every solder joint on the board once, in hopes tht a bad solder joint is the culprit.
2006-04-24, 04:02 PM
I am also goint to patiently await the post regarding the proper resistors for the 510 chip upgrade. Maybe somebody could get ahold of hte service bulltiten (thats how i got my 43fdx progressive scan problem fixed).
2006-05-07, 07:37 AM
I have a 43uwx10b. About a year ago I had to manually converge the set using the procedure found on this forum. Everything went great until I tried to Initialization. I came up with a "over flow" error written in red. So I lost Magic focus. The picture still looked fine. Yesterday the top left corner of the screen lost its convergence. After hitting the blue button to get the hash marks, I couldn't get the top corner to converge. Does this indicate the red convergence amp? Take your time responding, I'll be out of touch for the remainder of the week.
2006-05-11, 07:32 PM
I'm having the same problem wiht losing magic focus. Is there a way to get it back?
Not sure what you mean.
1. Do you get static mode?
2. Do you get an error message?
3. Is the picture slightly off due to poor convergence?
4. Is the picture way off due to convergence that's so poor you can't watch?
5. Which TV model do you have?
2006-05-12, 10:15 PM
I have a Hitachi 43UWX10B thats about 4 years old. I get static mode only, unless I push the little blue button on the front left (facing the set) side of tv. After pushing the button I can get the dynamic convergence patterns. I can get into coarse, medium, and fine patterns. After converging with all 3 patterns, still can't bring the red into the into the pattern on the top left corner, I try to initialize. I still get the "over flow" error message written in red. I don't necessarily want to save this setting with the red being out, I was just trying to get Magic Focus back. The rest of the picture looks good, just the top corner is out.
hmm. I don't understand why you can't get into "course or medium" (I believe fine is the default). Be sure to follow the directions exactly, as these have been used by people for >4 years. Note that the grid doesn't change, the cursor simply skips a line in medium.
If you try to do the convergence using only fine, you'll often end up with a "wave" pattern to the colour that results in problems and the overflow. As the DCAM instructions indicate (I'm assuming you're using the instructions in the sticky at the top of the Hitachi forum here), if you get this "wave" or "S", the only way to get rid of it is to go to medium or course. I've found medium is usually adequate - do a medium convergence first and then the fine is easy.
It sounds as though your IC's are not yet "shot", but they may be getting there...
Once you've pressed the blue button and done a proper, saved convergence, you should be able to press Magic Focus again, however, I suggest you don't, and simply do a DCAM every 6 months or so, since it only takes about 15 minutes once you've done it a couple of times.
DCAM instructions link.
I was having convergence problems with my Hitachi 43UWX10b and replaced 2bad resistors and the 2 STK392-110 amps. After reinstalling the circuit board I tried powereing up the TV. No picture. The red power light flashes near the power button on the front panel and there is a clicking noise coming from a green light on the center circuit board. Any suggestion for a fix? I don't mind trying something risky as I don't see the sense in paying for a repair when this model has a history of recurring problems. If I can not fix myself, I will start saving for another TV.
Thanks for your help.