: Hitachi & Other Manufacturers Convergence Problems (STK392-110 ICs) Read Post 1
adgnz 2007-09-09, 06:21 PM I have a 6+ year old Hitachi 53SWX01B. I had the convergence problem 15 months ago and happened to find your forum and was able to make the repair myself. Thanks!
Recently, we noticed some convergence problems during first power up that went away after the set was warm. Yesterday, the problem changed to no picture and no sound. From the troubleshooting diagram, I noticed that DP37 is blinking.
- 1. Turn OFF power SW
- 2. Wait for 3 seconds.
- 3. Turn ON after several seconds, and carefully observe green LED's.
I only see green DP29 (and don't believe there are others to check). Anyway, both DP37 and DP29 stay on after power off, fading after more than 3 seconds. The DP29 green LED stays on (or is at least more visible for ~10 seconds.)
Can you suggest what to check next?
Thanks
skharris 2007-09-22, 03:10 AM Just a thought regarding the afore mentioned heat problem causing an eminent failure on these Hitachi RPTV's.
I am a computer guy who has modified a number of customs systems all using what is termed "over clocking" of various components which causes heat issues.
One of my solutiions to lower the overall temperature of a given component was to create the best possible heat transference to the heat sink. I did this by using a high quality thermal compound such as arctic silver which can be purchased at any good computer specialty store or website at a reasonably low price. There are any number of good compounds that can be used but you should none the less do you research on whatever product you decide to go with.
I believe this may be a potential long term solution to the heat related convergence problem.
If the end result of this is maybe to just extend the the time between failures may I suggest replacing the heatsink with a copper one which is a much better conductor of heat than the standard aluminum ones that come with these TV's. Fabricating a heatsink may be more work than most are willing to take but with a little time and effort and the right thermal compound my belief is that this problem will never come back to haunt you again.;)
turbogentwo 2007-10-11, 08:52 PM this is not a reply to the above but I have a question my hitachi is a 53udx10b and i get all of the mentioned issues and when I do my magic focus it stops and shows a number 4 is this the same issue of replacing the SDK amplifiers because when I replaced the single resistor as soon as I turned it on it smoke and blew the same one again? Any help would be appreciated...sorry if this has been answered before I looked but could not find similar posts. Thanks in advance!
Same issue. See post 1 of this thread. Note that you need to replace both ICs, the resistors on the convergence circuit and check for cracked solder.
turbogentwo 2007-10-12, 05:18 PM Ok just replaced the single ic now and replace the resistor that was going on now when I turn it on the power button blinks any ideas?
Did you check/replace all the resistors in the convergence circuitry? Did you check for cracked solder? I assume there is only one IC on your TV?
If you did all that, if you want to throw more money at it, I guess it's time to call for service.
turbogentwo 2007-10-12, 06:30 PM well ok it was the ic looks like it was touching another pin fixed it now it turns on I have two but only replaced the one that was burning out the resister; when I go to magic focus it won't let me adjust green in the middle it looks concave or convex depends how you look at it but anyway I adjusted it as much as I could but when I cleared out of it it still showed the pictures all messed up is something that I'm doing wrong? I replaced the ic unit that was on the green side of the panel
If you want to do this piecemeal, it's OK with me. The first post clearly states to replace both ICs and to check/replace the resistors in the convergence circuitry, and check the board.
While the board is out and you're doing all the other stuff it simply makes no sense to only do one IC. If the IC wasn't put in properly (touching pins), then that IC could be shot again - doesn't take much.
turbogentwo 2007-10-12, 06:44 PM are the green lines convex at top or are they all suppose to be straight across?
turbogentwo 2007-10-12, 06:47 PM ok so if I can move the red then which Ic is the green? I thought the ic that kept burning up the resistor was the one at fault
I'm sorry, I'm not a technician and I can't help you further. Perhaps someone else can advise you. The thing is that everyone replaces both ICs (all ICs - 1, 2 or 3 depending on the model) when doing this repair - it's simply the proper thing to do. They then also check all the resistors to ensure they're OK and replace those if any are bad. They then do a continuity check on the board. All of this is done before replacing the board and firing up the TV.
A few people have been lucky and only needed to replace the ICs, however, many people who have tried that approach ended up regretting it when in a few seconds/minutes/hours/days/weeks the ICs failed due to a resistor being out of range. This is why the kits are a good idea. You replace what's in the kit, do a continuity check and are ready to go.
turbogentwo 2007-10-13, 12:08 AM I understand but you have been the most helpfull so far..ok I replaced both ics and I still have the ability to move red and blue but cannot touch green and it is like concave on top and bottom what else is there? what am I missing oh and when I try to save to rom it gives me connect1 no 1 3 5 7 what is that?
You did the ICs, but did you do the resistors? If not, that could be the problem. If you didn't do the resistors, then don't run the TV because that can blow the ICs again, as mentioned in post 1.
Also, the problem could be somewhere else in the convergence circuitry, although the IC/resistor replacement usually does the trick.
When you try to save a convergence to ROM that is too far off, you usually get some error message, like overflow, or something. Here's the DCAM thread, although I'm not sure it applies to your model - yours may simply have the 9 points or something:
http://www.digitalhome.ca/forum/showthread.php?t=9539
Good Luck.
turbogentwo 2007-10-13, 12:36 AM thank you yeah I replaced both resistors that were bad and both ic's do you think maybe one of the resistors is bad? what does connect1 mean??? and those numbers what do they all mean?
I replaced both resistors...I thought there are more resistors on the convergence circuit (more like 6)? Did you contact the people who supply the kits to see what resistors are necessary for your model, or look at their website? (post 1)
...connect1 mean??? and those numbers...
Sorry, don't know, could be error codes of some kind, perhaps there's a bad connection somewhere?
turbogentwo 2007-10-13, 08:44 AM Well I only replaced the ones that were blown.
nicefruit 2007-10-14, 11:00 AM Hi - After browsing this very informative thread, this is what I got myself into:
approx. 7 year old Hitachi 53UWX10B convergence problem. Could not adjust green vertical and magic focus error 4. ordered repair kit 10 consisting of 2 stk392-150 and 6 resistors from vendor mentioned in this thread. Downloaded Service Manual and created/plotted convergence jig. Replaced parts, re-installed board with same problem. Pulled board to check for required continuity between replaced components and inspect for visible defects. All looks good, but still cannot adjust green vertical no matter how hard I press the joystick.
Anybody have any ideas before I start to troubleshoot via the Service Manual? Do not have new chips on hand to swap. Was thinking of switching IK04 with IK05 to see if I get green vert back, but at this point, I am ready to go at this thing with a chainsaw. There's no way in hell I'm putting this thing to the curb in one piece.
Any help would be greatly appreciated. Thanks in advance.
Gary
Hello
Newb here with a question:) . I have a Hitachi 53uwx10ba as well with a convergence issue. when I run magic focus I get " 4 " at the end. I would imagine this is an error message? what exactly is that error message mean?
Please excuse my beginer questions This is my first Big screen and I have no clue how to work on em . I am going to have a repair tech fix the set I just want to make sure I know what it's gonna cost before hand
Thanks
Carmine B
Um, please read post 1 of this thread. The error message is typical of blown convergence ICs.
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