Please help with Mitsu convergence problem!

[stewartg]

I have a three year old 65" Mitsubishi HD rear projection unit. Its got a weird problem...

Sometimes when we turn the set on, the RGB convergence is WAY off, gradually from the center of the screen to the outside corners. To explain - the very center of the screen is converged, and as you go out to the corners, it becomes separated by up to about an inch. After a few minutes, the screen just "pops" back into normal. Sometimes smacking the side of the TV (no flames please!) will get it to "pop" back into normal. Over the past few weeks, its taking longer to fix itself and smacking it doesn't seem to work.

Any ideas?

If we need a tech in Houston, can y'all suggest anyone? Perhaps someone that can recalibrate well after the repair?

Thanks for your help!

StewartG

[pbmax542]

An alternative to hitting your TV would be to make it sit on its bed for 5 minutes. This is called a “Time Out.” Physical abuse is not the answer.

You can use this link to find an ISF calibrator near you, who may be able to solve your problem. http://www.imagingscience.com/isf-trained.cfm

[stewartg]

Technically, experts recommend one minute in time out for every year of age. The TV should probably only have three years in time out, anything more might traumatize it.

Seriously though, at this point, I'm more interested in diagnosing and fixing the problem than worrying about calibration. (I've put off the calibration for three years already...)

Does anyone recognize the problem I'm having?

More importantly, does anyone know of an honest, reasonably priced repair tech who can fix it here in Houston?

Thanks for the help!

StewartG

[Sinastar]

Immediately upon starting the tv put up the internal convervence grid. Or put up a geometry grid from avia or dve. Note if all three guns are off or just one or two.
Call and personally talk to repair person and see if he has any idea what the problem is and how much he thinks it will cost to fix.
And quit hitting your tv or i'll turn you into the SPCRPTV.
Society for the Prevention of Cruelty to Rear Projection TV's

[stewartg]

Thanks for the reply! I've already tried what you suggested. The result is very weird. All three guns are misconverged by the exact same amount. After warm up... POP - picture is perfect again!

I'm going to start hunting for a tech in Houston tomorrow. I just don't know where to start looking... (other than yellow pages)

StewartG

[Sinastar]

There is what they call a "convergence board" inside your televison.
Probably need replacing. Maybe there's a loose connection in it.
Hitting it gets it connected?...what do i know.
Main thing is don't get a repair man over there that will start turning
the guns and messing around with the convergence. Seen a few sad posts
like that. Keep an eye on 'em while he's fixing it.

[pbmax542]

I had a slight convergence prob, so I called my local sears repair man out to fix it. After 5 days of calibrating, the tech had made my picture so bad that his only suggestion was to have the set replaced. The moral of the story is, don't let a redneck guy named Ray work on your TV.

[stewartg]

See, thats the thing... The repair guy shouldn't even have to BEGIN to adjust convergence. That is NOT the problem... After the warm up (or the slight smack to the side of the TV) the convergence is perfect.

If I had to guess, I am thinking there is a slight short or something that, when heated, reconnects...

(Good a guess as any, I suppose...)

StewartG

[robert123]

It sounds like there is a bad connection, most likely on the convergence amplifier ICs. These are the devices that generate the most heat.

Robert

[fandale8]

Stewertg,
My ws55813 does the same thing..ie. when I turn it on the convergence are out of alignement. After 2-3 seconds or change of input the convergence are OK???

Now. My set was just calibrated by Greg(Feb 4 '05)..I had this trouble before and after calibration. Maybe this is a problem with netcommand, as for I had similar trouble with a 65511. Mit's replace it in october(ir shut down problem)

I do have a problem with my pronto changing the inputs to early and causing the tv to do strange things. It will show that it changed to s-vid input but black screeen until input is changed again.
And also the component and dvi conergence can't be algined at the same time. The set was cal. for component HD and so the convergence are off on DVI. when you algin the dvi, the conponent convergence are off. This happens from the center off to the right side..

[RCHELI]

I don't know if there are any electrolytic capacitors in the convergence circuitry,but with my experience with electronics 'warming up' and generally being bad then good-it has usually been due to an electrolytic going bad for keeps. If you can access them,if present,try some freezing spray (available at Radio Shack) or a REASONABLE amount of heat from a heat gun or hair dryer. The heat and cold treatment can also sometimes find a dry solder joint and other components on the way out.

[stewartg]

fandale8:

After you turn your set on, does your convergence "pop" back into alignment? Or does it slowly "drift" back into alignment? I was wondering if this were a problem other Mitsu owners were having...

RCHELI:

I appreciate the tip, but I'm not going to open the thing myself. I'll blow something up.

I was hoping someone would be able to give me the name of a good and reasonably priced repair tech in the Houston area...

StewartG

[fandale8]

Stewartg
I never really paid it any mind, so when i red your reply I turned on the tv. To describe it I would really say it looks like a b/w picture for just a second and then goes to a blueish grey and then all of a sudden it's fine. 3 seconds tops..
If my pronto sends a code within thoughts 3 seconds the tv does wier stuff.
fandale8

[ADevantier]

This is a problem with your power supply. It is not convergence problem. The repair is pretty simple and not that expensive. A repair tech that works on a lot of Mits sets will be able to fix it. BTW, it will get worse and worse as time goes by.

I had mine repaired for this last summer. I described the problem over the phone to my local repair tech. He was so sure that it was the power supply that he ordered the parts before coming by my house! He was right. Apperently, its a common problem.

allan

[sconner]

What was the cause of this issue? My WS-65908 is doing the same thing.

sconner
srconner@yahoo.com

[CountryJoe]

This sounds like something I have heard of with the IC Convergence board. I have heard that there is a relatively easy fix, if you are handy with a soldering iron. You might search here or in the Home Theater Spot site.

[hammerdwn]

If you can smack the set and watch the convergence pop in/out, then it could just be bad solder connection(s) on the convergence IC's. If you feel comfortable with opening the Tv up and doing some soldering let us know, otherwise calling someone will cost $250~$400.

Hammer

[sconner]

Well, I gave it a light wack a couple times and didn't seem to make any difference. But I didn't bump it that hard. Next time it does it I'll be sure to give it a beating.

sconner

[sconner]

I've since had this problem several times again and as stated, give it a few firm whacks on top and it pops back into alignment. So one of these days when I get bored I'll check solder joints.

sconner

[ecelis]

I have a similar problem as described here with my Mitsubishi WS-55807. where can I find some detail instructions on replacing the convergence ICs? And where can I order the parts?

[Rolls-Royce]

In most cases, the Mits convergence ICs don't have to be replaced, just resoldered. There is information about this over on the Home Theater Spot. The repair doesn't look to be difficult, just finicky.

[ecelis]

I went to the hometheater spot but could not find where to get this info, can you please guide me?

[Keith Ford]

I was whacking the side of my set to fix convergence for about a month. Then the whacks quit working and I had to pursue a proper fix. I paid the Spot membership and downloaded their article on resoldering the convergence ICs. The article was pretty detailed with pictures. It took about 2 hours to remove and install the circuit board and it is a bit tedious, but very doable. The soldering, once the board was on the kitchen table, took about 3 minutes. My convergence was back to normal after the repair.

[jtny71]

I have the same problem with my Mits, I didn't get it fixed, and let the tv sit around for a year. Well I think it's high time I fixed it, I miss my big screen. Off I go to the Hometheater Spot to grab a membership.

[WildBuddha]

I have a stuck RED to the right on my WS65908 did you find a way to fix the convergence problem?

[sconner]

Another update, some months back I took the mainboard out of the TV, flipped it over and just soldered the pings for the convergence ICs. I didn't acually go through the hassle of replacing the chips or removing all the old solder...just basically added more to each pin. In the end, it's been running for several months without any problems.

The entire job took me about an hour or so but most of that time was just getting all the screws and cables unhooked to remove the board. Took the opportunity to give it a good cleaning while I was in there as well. Lots of dust bunnies.

sconner

[jhirschtick]

Mitsubishi WS65909 bought 3/02. Now has intermittent convergence problems and other strange behaviors.

Set is at a vacation house. Worked great last Jan. Did not unplug from Jan to June when house was idle (I know, mistake). Came back in June and set would not respond to remote. Picture was unviewable. (power surge?)

Unplugged for one day, then it worked fine -- for an hour or so. Then started to intermittently jump back and forth from normal picture to bad convergence (old 3D movie look, with image warped in an arc shape).

Leave TV on and eventually it will not respond to remote control and will be permanently in the bad convergence mode.

Called a repair service and the guy sounded confident he could fix it. I have also seen this thread suggest either resoldering convergence IC's and/or power supply problem. I suspect power supply since it is not just the convergence that is acting strange.

Advice appreciated. Thanks, - Jon

[sconner]

If it was just the convergence acting up I'd say for certain it was the convergence IC chip needed re-soldered. Remote not working? Don't know how that could be related to either IC or PS? Dumb question, but maybe batteries flakey? Remote flakey? Have another universal remote to try?

sconner

[Mr Bob]

I have seen this type of thing countless times in my 20 years plus in the repair biz. Convergence going out on CRT RPTVs is very common, like a thermostat going out on a car. You just remedy it and keep driving her, it's really just a bump in the road.


If it's still intermittent, you have a chance to fix it without having to put new parts in. If it has gone over the edge to not snapping back in, chances are the parts will need to be replaced. When cold solder joints cause non-connection, the ICs start getting run outside of their design parameters, eventually causing them to overheat and/or simply die. They could also short, causing the power supplies feeding them to be compromised. I have seen this happen, where the set actually shuts down permanently after a certain point, because the power supply that runs the +24v to the ICs has been shorted, and that's what allows the set to turn on. Without it, it just stays in shutdown.

So don't dally once your set has gone intermittent! It could get worse. Get it fixed ASAP.

If your intermittency is still alive, resoldering your ICs - which get ungodly hot in there - will usually restore everything without further ado.

It's a pain getting in to do that resoldering, tho, and that's where all the time and energy of this fix goes.

All HDready Mits have a light box that is removable from the main box, for spiriting down to the shop. It involves removing 4 screws on each side - 2 big bolts on the floor and 2 flatheads at CRT lens level per side, all screws/bolts #2 Philips head - plus disco'ing the wiring to the front of the set. This is much easier and much safer than disco'ing all the wiring needed to get a board out, and taking a board out, where you might inadvertently mess something up when you put everything back together.

Once removed from the main set box, the light box can then be up-ended to reveal the legs of where the ICs are soldered in. The resoldering itself is very straightforward and only takes a few minutes. As already mentioned, just adding a bit of solder to each leg is all that is needed.

If you need to replace the ICs, be sure and be liberal on the heat sink compound, as it is critical for heat transfer away from those ICs to the heat sinks themselves.



But replacing a board when there is a convergence problem is never the best solution. Starting out from scratch on your geometry and convergence is something that requires lots of time and experience just to master, let alone accomplish with finesse. And is not needed when you simply repair the board in question - as in resoldering or replacing ICs, rather than replacing the entire board.


Mr Bob


PS - your convergence paradigm in there might be overheating the ICs. I have seen some really dorky work done on the convergence at the Mit factory, with lots of registers fighting each other.

This can all be straightened out, and I do so whenever I encounter it, as part of my basic calibration package. Just like optics cleaning, which is another absolutely essential part of that package. I encountered one Mit HDready where all the numbers in the point system were positive, and in the hundreds, whereas they SHOULD all revolve around an average of zero, plus or minus. When I zeroed them all out to start over, the picture had shifted itself to the side by 7"!

So if you have me calibrate your set and it has these registers fighting each other in there and causing excessive heat by so doing, that sloppiness on the part of the factory gets cured in the process.

[Mr Bob]

Originally Posted by sconner

Remote not working? Don't know how that could be related to either IC or PS? Dumb question, but maybe batteries flakey? Remote flakey? Have another universal remote to try?

sconner

All Mit HDreadys have had problems with their coolant leaking in an appreciable number of their sets. This should be checked for, any time freaky problems start cropping up.

If your Signal board has been compromised, you could be SOL. The other 2 boards under the CRTs are single sided and as such can always be repaired.

The Signal board, beneath the blue gun, is a 4 layer board, and once infected with coolant penetration, will eventually usually be history, even if cleaned off now. That coolant really does a number once it has penetrated that board's layers.