[ichosethis1]

Hi Lcaillo, I am working on my old Rear Projection TV Mitsubishi VS-5043 for Convergence problems that it has had for some time now. I was actually given this TV by my father about 8 months ago because he got tired of having to hit it to get it back into convergence and went and bought himself a new Phillips flat screen. Ignorant as we were, my fiance and I were happy to continue smacking it around because the picture was so good when it snapped back in line.:duh: Now I fear we have allowed the problems to get worse. Last week it refused to cooperate, no matter how much we slapped it around, it would no longer straighten up, nor would the red cross hair so much as budge when asked from the convergence setup. So I decided it was finally time to figure out the real problem. After digging around on the web, I finally came upon your wonderful forum (something I wish I had done 8 Months ago) and saw where you had told someone to re flow the solder connections to the STK's. Well I did that,and in the process also found a blown inductor on the board which I replaced, and actually got control back of my red cross hair. However my convergence is still not fixed, and leaves a really wicked drop shadow on all on screen displays. I assume that one of my STK'S must have finally bitten the dust. Could you please point me in the right direction of a vendor that would have a kit of all the common replaced convergence parts for my particular TV and hopefully some instructions? If it helps the amps are STK391-020 and it uses 3 of them. I am a little worried because I found the one 10uH inductor smoked in half Next to the middle STK on the board and am afraid more components may be harmed(although none are apparent). I have recently been layed off from my employer of 9 years, and cash is tight, so calling in the experts is not an option. I have a multimeter, and a soldering iron, and am pretty good at following directions, when all else fails. Any help you could offer would be greatly appreciated.:hail:

 

[ichosethis1]

Thanks for the quick reply, i have already removed the heat sink in preperation of replacing ic's would it be harmful to power up long enough to check voltages? how do i know what voltages should be where?

 

[ichosethis1]

also are you refering to acme in orlando?

 

[ichosethis1]

Thanks, I found you on their "what people say about us" page so I went ahead and ordered the parts from them. Wish me luck.......

 

[ichosethis1]

I don't have the schematic for it. I've been searching the web, but so far no luck.:huh:

 

[ichosethis1]

:gah:Yes, I am finding this manual to be nearly impossible to find so far.........

 

[ichosethis1]

Sorry, I have been searching for a free one, cause I just don't have the funds, at the moment. I did receive my parts today and went ahead and removed the ics, and checked all the voltages at the ics holes to ground on the board after removal, against each other and I recorded the voltages for future reference. They are all pretty much the same voltages pin per pin, ic slot to ic slot. So without schematics, I believe the voltages are ok. However after checking voltages, I installed the new ic's I received from ACME, and I still have the drop shadow. I analyzed the image carefully and it appears that my green image is hour glass shaped pulling in on either side in the middle. on the 5 point convergance setup the center crosshair is fine but each corner setup the green crosshair skews off towards the middle( and if my assumptions are correct the middle ic controls green and that is where the 10mH inductor blew.)I am still worried that something else on the board was harmed when the 10mH inductor blew, but I have so far been unable to find any obvious bad components. I have checked every fuse, and pico fuse i can find, but all read good to the meter. :help: Also when I installed the ic's I used
Arctic Silver heat sink compound lightly applied, and double and triple checked all my solder connections, and am absolutely positive there are no cold solder joints or solder bridges. and nothing is unplugged. I really miss my TV, but do not want to run it till it is fixed. what do i do now? heres some pics too...



all your help is greatly appreciated:yes:

 

[ichosethis1]

Ok, I Acquired the manuals, but I'm not really sure what I am looking at. I went ahead and attached them to this post for you to take a look at if you would be so kind. (who knows, maybe you could use them yourself in the future) Maybe then you could point me in the right direction....I feel sure this should be a simple fix, but I guess I'm an even simpler troubleshooter, LoL........I'm more of a computer geek than a TV geek, if it were my computer doing this it would be a simple software adjustment. Again, I can't thank you enough for the help.

 

[ichosethis1]

Well I still thank you for your help getting me this far. If you are ever in Tulsa, send me a message and my fiance and I will buy you dinner.(Maybe I'll be employed again by then, and can take you out for a steak 80) ) I will continue to beat my head against this thing until I figure it out or blow it up.:yes: I will post my findings, if I figure it out in case it can help someone else with hourglass shaped green image. Keep up the good work sir.:T

 

[ichosethis1]

All of my voltages appear to be spot on, and all the resistors I have checked that pertain to that circuit seem fine. I don't have an o-scope or function generator, or even an LC analyzer, however the capacitors, when checked with a digital multi-meter give the appearance of working, ie they seem to "charge" while trying to read resistance. I have checked resistance from each leg of each STK to it's nearest trace neighbor, to be sure there was no damage to the board from failure/replacement, and all check good. Also there is absolutely no visual sign of any component failures on top or bottom of the board. Now that i have replaced the STK's and the one burnt inductor, could it be in any way possible that this green hourglass image is something I can correct in the factory level setup menu's listed in the manual? If so what would this problem be called? I am working on getting a hold of a copy of the Digital Video essentials dvd, so that I will have a source signal to feed it while testing. At present it looks like it will take a couple of days to acquire. Could you recommend any other video "test signal" resources? I hesitate to start making changes in these factory setups, if that in no way could help. But if it comes to that I will, making sure to record all original settings first......I ain't giving up yet.............addle:

 

[ichosethis1]

Thank you, that's where I will go next. I didn't go there first because of the blown inductor, I wanted to be sure there were no other burned out components. I was afraid I'd make a simple fix into a simple nightmare if I started adjusting for bad components. I am fairly convinced now that the circuit is good so i will start going through this process next. I am still trying to get a hold of the video essentials DVD, may get it hopefully tomorrow. Is there any other reference resources you could point me to for going through the convergence and geometry setup? I am definitely gonna owe you a steak dinner when this is over........:hail:

 

[ichosethis1]

Ok, well I got a color crosshatch from the internet, and went ahead and went through the service menu setups. First I carefully wrote down every current set point in every category. I didn't find the eeprom reset option, however I was able to adjust every adjustment in the setups. After trying every adjustment I have determined that all of them only affect the red or blue channels, or all three at once. there were no settings for only the green channel. I also deduced that my problem is a green E W pincushion issue, due to the fact that by making the E W pincusion adjustment from the original setting of like 126 down to like 32 i could make the red and blue channels bend to match the green channel. (I guess if I had to i could always resort to that for watch ability, UGH) So I guess I am back to a component issue? I tell you what, I have learned more about big screen tvs in the last week than I ever wanted to, but I'm not gonna give up yet. One thing I can say for sure, I don't want your job............:sob: by the way while adjusting things I didn't go to the extremes so as not to stress stuff and I returned each setting back to its original set point after each trial. I still don't know why they didn't include any of these adjustments for green. that would make things a lot easier.

 

[ichosethis1]

Well, I went back through every setting in service level today, and none of the adjustments corrects the hour glass shaped green image or even tries for that matter. I guess I will start replacing capacitors in the green circuit as money allows since I have no good way to check them for spec. I will keep you updated with my progress......don't give up on me, I haven't yet.....LOL.:scratch:

 

[ichosethis1]

yes on my set it calls it "con geo", I also went through "con"vergence set as well. Actually I played with every adjustment allowed in the service menus, as well as the consumer menus, but nothing straightens the green hourglass. I put everything back to original settings after testing. I was really hoping that it would be a setting in there, but it appears not. So I can only guess that one of the filtering capacitors is out of spec. As i said before, when I change the ew pincusion, I can move the blue and red into the same hourglass shape if I want, which I suppose would make convergence work, but that's not a fix, as the image would be distorted on either side. the center of the grid looks goodin the center 1/3rd of the screen. It's just the left and right sides that curve in on green channel. The only settings i didnt play with were the sap/audio settings, and the pip settings, and the high voltage adjustment.