: Hitachi & Other Manufacturers Convergence Problems (STK392-110 ICs) Read Post 1
2010-05-11, 10:41 PM
While I consider my options, does anybody know if my colorimeter-based calibration would be intact after a convergence repair?
I'm wondering if my TV is too old to bother repairing. Still had nice grey scale/color up to this incident.
After seeing some internal RPTV photos in this thread, I wonder if heat problems damaging components are accelerated by the dust bunnies. I've never cleaned mine out.
1. It will be - mine was, although you will likely need to redo your convergence - manual DCAM is best.
2. That is up to you. I was also happy with the PQ of my 9-year old Hitachi - the only thing it lacked was resolution and my new plasma looks very similar to the RPTV, excepting resolution.
4. Heat is certainly one source of the problem.
Part of the reason I changed out my TV a couple of months ago was my desire for a new DVD player (BD) and new (HDMI) AVR. Both of mine were about 10 years old.
2010-05-12, 06:07 AM
To clarify #2, I was wondering what the statistical likelihood is for no more hardware repairs of any kind for the next year, 2 years, 3 years, etc. I need an actuary.
My TV has resided all its life in an air conditioned room.
I'm not skilled at TV hardware repair.
I got my TV repaired around year 4 and it was still fine in year 9. Based on what I've read in these various threads regarding the IC failure, most people who do the repair properly don't need to repair the TV again, athough some people have the ICs go again fairly soon - I assume due to a failure like not replacing the resistors as outlined in post 1 of this thread. Of course, there are no guarantees.
2010-05-12, 05:08 PM
I just thought of this: is there a possibility of per-CRT gun convergence failure? Right now my problem is Blue; but in the future could Green & Red each crash independently, having their own set of ICs, board, and other components, requiring an additional separate repair?
I looked in the service manual and see a single Digital Convergence Unit.
BTW, spending 2 hours today at BestBuy, browsing TV tech, I spent some time watching a 55" LED TV show a demo loop with a BD version of Dark Knight, and I was awed, from every visual aspect, to see very high color and grey scale clarity on such a large surface. My first BD viewing experience; luckily, with exceptional source material, and a great TV.
2010-05-26, 07:05 AM
Well my faithful Hitachi of 8.5 years has just caught a serious convergence sickness. It is seriously off.
It seems reasonably feasible to repair thanks to the information provided here on this fantastic thread. However I remember that lamp life expectancy / dimming was a potential concern when I purchased it (convergence was never mentioned).
So the eternal question is does it worth fixing considering the likely risk of having to replace the lamps in a perhaps near future when taking into consideration the pricing of 1080p plasma TVs?
With that age, I would probably look into a 58-60" plasma since that price range is sort of a "sweet spot" - if you can afford the expense now. If you wish to move up to a 65", then you need to expect to spend quite a bit more. I just replaced my 61" Hitachi a couple of months ago with a 65" Panasonic even though the Hitachi was still providing a good quality picture. The item I noticed most was the difference in resolution as the colour and black levels were similar. I also replaced my 10 year old DVD player and AVR at the time, so everything went HDMI. See link below for additional info.
If you wish to discuss upgrading in more detail, please post in the plasma forum here, as this thread is regarding the convergence issue.
2010-05-26, 10:58 PM
Thank you 57. You may just have given me the last push I needed to make the jump. I will check out your link and the plasma related threads. I also upgraded my a/v hardware this past year and the Hitachi is the last vestige of the past.
I loved the Hitachi that had a far better picture than our other HDTV, a Toshiba DLP, and will be missed. Impressive its colour and black levels are still competitive with the best of today's technology; my model's overscan was a bit much and probably hurt more the actual resolution that I realized.
Thanks for all your good work and dedication over so many years.
2010-06-07, 11:03 PM
Thanks for all the great info here. I too have a convergence issue.
We smelled electrical burning, and then the image went haywire. I opened the back after reading all the helpful posts here, and found that a wire bundle had slipped from wherever it was, and come to rest on top of two resistors on the convergence board. The wires' insulation melted (but it doesn't look like they shorted) and the two resistors are visibly charred.
The chips might still be ok, and I'd like to try just replacing the resistors and the wire bundle. The resistors are numbered r58 and r59 on the board.
Any info on what they're supposed to be? I can't read the colors through the char. Any info on the best place to get them and a wire bundle with clip?
Thanks for any help you can give.
2010-06-07, 11:09 PM
in fact the wire bundle that fried is the one in the second pic above posted by the big guy. It's the one with the purple orange black and brown wires right in the front of the pic. It came to rest on those resistors behind the heat sink for the chips.
2010-06-22, 04:56 PM
I guess it is my turn to torment over whether to replace the IC's and resistors, or go for a new set. We just got a new furnace installed yesterday ($$$) so the timing couldn't be worse. We went to turn on the TV this morning and BAM! - the convergence went instantly. It was not gradual over time.
Below is a pic of my DCAM screen when I went to fix the convergence. It is immediately apparent that the green is the issue. The attempts to move the green up or down had no affect. I could however move the green left and right (as expected) but that was not my big concern. I have read that it is recommended to NOT adjust the green too much but move the red/blue to the green. That would not work for this scenario obviously.
I will give it a few days before ultimately deciding. Sad really as although I miss the connectivity of the newer HDTV's, this set had sentimental value.
2010-06-25, 02:45 PM
I ordered the I/C and resistors. While I impatiently wait for Canada Post, I've noticed the former Newcomers Forum is no longer on this site. I had posted links to the service manual for my set there for any that need it.
Since it will be useful for future readers I'll post them again. Both files must be downloaded and used together.
51GWX20B.ZIP (24 MB .pdf) - Service manual for several models listed below (DP number is the chassis type)
43FWX20B DP24 :
46F500.ZIP (1.3 MB pdf) - Addendum to the above service manual which outlines the differences between the 51UWX20B and the 46F500:
Hope this helps others.
2010-07-09, 09:56 AM
I have (had) the convergence problem described here on my Hitachi. Unfortunately, the TV was used a lot after the problem occured. Some of the posts say this could lead to bigger problems, and it has. The TV now does not display any picture or sound. When the power button is pressed, you can here the relay click and the red light on the front panel comes on but no picture or sound. Can anyone tell me what additional damage may have been done and how to correct it?
This same problem (no pic/sound, not the convergence problem) occured a couple of years ago and it was the video chip. Maybe, by coincidence, that chip went out again? Or, has using the TV with the bad convergence chips done other damage?
Thanks in advance for your help.
2010-07-14, 06:34 PM
FWIW, I am not qualified to give TV repair advice, but to me that doesn't sound convergence related at all. The convergence board on my set has a distinct power input. A call to your local repair shop will likely tell you whether it is worth the fix or better to place your money into a new set.
Well I replaced the convergence chips and two resistors over the weekend. I also cleaned the lightbox interior components. When I get a chance I'll post some pics of the repair process since the 46F500 is somewhat unique - the convergence board is also home to the flyback transformer which for safety reasons I was not going to disconnect. That meant a on-the-spot repair job. Unfortunately the solder side of the board where one of the convergence IC sat was obscured by a plastic PCB support. I had to cut a portion of the support out to access the solder points for the IC.
I had to do the blue button trick after the repair, since the convergence mode was locked into "Static Mode" for some reason. I think I may have tried to save to ROM and got the Buffer Over Run error prior to doing the repair but it has been weeks so I can't recall exactly. Unfortunately, I haven't had a chance to do the full DCAM convergence since. I can see obvious minor convergence touch-ups need to be done (especially when looking at a stationary screen with lots of straight lines - like Bell's IPG), but Magic Focus doesn't get the convergence properly like it used to. So when I can get a bit of time I'll get it tweaked if I can.
Thanks for all the great tips from 57 and others that I gleaned from this thread prior to doing the repair.
2010-07-15, 09:36 AM
I picked up a 60ux58B from a lady that had a dead board. I replaced a pico fuse, resistor and some bad transistors and now have the TV working. However my colors are off and there is a bow top and bottom. The TV had been out of commission for about 3 months before I got it.
Would I be better off replacing the Convergence chips or would I be able to make the adjustments in the Magic Focus? I have tried the steps here as well as from a manual I found online, but my remote does not seem to react as published. If anyone has a service manual they would like to share, send me a PM and I'll share my email address to send it to.
Any advise would be greatly appreciated. Thanks
2010-07-15, 10:22 AM
I got my 43uwx10b about 5 years ago, Did the dcam adjust for about 3 years, I got it close but always had a bow at the bottom that I lived with, finally got some time last winter, I ordered the pair of STK392-150 on ebay for $25, and a few of the burnt resistors, wow, after a new dcam it is perfect, all grids right on just be sure to watch for solder bridges, there are a lot of close pins on those chips and you don't want to blow a $ chip or burn up some other parts on the board. BTW I don't have the correct remote either but I could do all but the course mode, but thru trial and error got enough functions to do a full dcam. Just follow the steps carefully and don't skip any.
Rturner. I moved your posts to this thread on the IC issue. Please read post 1 of this thread carefully and thoroughly. It's unlikely you'll be able to do a proper convergence until the IC issue is repaired.
2010-08-05, 05:07 PM
I am trying to fix the convergence problem of my 42H83
Could anyone tell me how to disconnect these two types of connector ??
Thanks alot !!!
2010-08-06, 12:45 PM
Those are different forms of bridge connectors; in your case they are connecting two different PC boards together. Each side will consist of two parts: an under-mount/adapter that is soldered to the board, and an upper connector that will likely have locking tabs attached to secure it to the mount. Occasionally the locking tab will be part of the mount/adapter and not the connector.
There should be a "locking" tab on at least one side of those bridge connectors. I would guess that at least for the top two (white in your pic) there is one on the outside of the left side of the bridge at the wide point.
Try gently prying outwards with a fine tip standard screw driver (e.g. jewellers/electronics type) on the undermount in various areas starting with the middle or widest areas. A little pressure inwards on the connector may alternatively yield results. The connector may not release upwards (vertically)! It might release in the horizontal plane (i.e. parallel with the board, towards the other PC board.)
best of luck.
2010-08-08, 10:47 PM
I have a Hitachi 46F500 (DP23 chassis) with convergence issues. I have 2 new STK392-180 IC's to replace the old ones. I pulled the board and checked the 6 convergence resistors and RK54 is fried. The colors on the resistor are no longer readable so I got the service manual to find out what it needs to be replaced with and to verify the 5 other resistors. I verified that the color code and the multimeter reading matched the service manual (found in post #692 of this thread). The problem is, only 4 of the 5 good resistors match up with what the service manual specifies. The manual specifies a 3.3 ohm resistor in RK42, however, my board has a 3.9 ohm resistor there.
So now I'm not sure what to do. Should I just leave RK42 alone and only replace the burned RK54 resistor with what the manual says goes there? Should I just replace all 6 and if so, what should go in RK42 - 3.3 ohm or 3.9 ohm? If its advisable, I figure I might as well replace all 6 while I have the board out already. I guess I just wasn't expecting to see a mismatch between the service manual and the board and now I'm not 100% confident that RK54 should be a 1.8 ohm resistor like the service manual says.