Mitsubishi DLP

[PlainBill]

This one is personal. The subject is a 65" Mitsibishi DLP HDTV, Model WD-65731. It has developed a problem with color shifting. I've done extensive searching but have been unable to find a forum that is frequented by TV technicians, or even a post by someone who has had the same problem solved.

The problem was first noted about 9 months ago. It would occur in the late afternoon if the TV had been on for several hours. (At that time of the day the temperature in the room would be in the low 80's. It gradually got worse until it now occurs within an hour on even a cool day.

The first sign of a problem is a slight flickering which gets worse, eventually it will stabilize at the bad state. All air filters are clear, all fans I can reach are working. The local Mitsubishi authorized service center has indicated they want me to bring the set in.

Picture 1 is the set with a good picture, Picture 2 is the set with the bad picture. Does any one know a more appropriate forum?

Thanks,

PlainBill

[Toasty]

Re: Mitsubishi DLP

Hang tight! Wizard should be by any moment...

[Wizard]

Re: Mitsubishi DLP

Sounds like color wheel drifting especially if the bearing is failing. Also you should hear bad noises also.

Cheers, Wizard

[Toasty]

Re: Mitsubishi DLP

!!!!!!!!


I gotta remember that one. ROFLMAO!

[PlainBill]

Re: Mitsubishi DLP

Sounds like color wheel drifting especially if the bearing is failing. Also you should hear bad noises also.

Cheers, Wizard

Thanks. A combination of elderly ears and tinnitus pretty much prevents me from hearing any bearing noise.

I presume the solution would be to replace the optical engine? I do have the service manual, but of course they don't include troubleshooting information. Asking as politely as I know how, what's your confidence level in the diagnosis?

Thanks,

PlainBill

[Toasty]

Re: Mitsubishi DLP

LOLOLOL! Good response! You have a sense of the rather dry humor that pervades the forums!

Where are you in terms of manuf. warranty?

Do you have any technical experience with electronics that would allow you to repair it if we help? Do you have any repair equipment & related knowledge of use?

Have you tried to examine the problem?
Taken the set back off?
Taken any readings or looked for obvious signs of the failure?
Roasted or burned parts, board discoloration?
Bloated capacitors?

Is the manual a paper document or a PDF? If PDF, can you provide us a copy?

Pictures! We LIKE pictures!!

[Wizard]

Re: Mitsubishi DLP

Invite a person with good hearing and advise you on the potiential noise with this tv. particularly when turning on and running.

Color wheel is easy to do, just swapping out but price is kinda expensive. 120-150.

Cheers, Wizard

[Toasty]

Re: Mitsubishi DLP

OMG! It doesn't stop!!

(He must've gotten into the triple cappuccino supply again!)

[PlainBill]

Re: Mitsubishi DLP

LOLOLOL! Good response! You have a sense of the rather dry humor that pervades the forums!

Where are you in terms of manuf. warranty?

SOL. The factory warranty expired over a year ago and I declined the extended warranty offered by the dealer.

Do you have any technical experience with electronics that would allow you to repair it if we help? Do you have any repair equipment & related knowledge of use?

Repaired both tube and solid state TVs. Can read schematics (if the print is large enough). Worked for 5 years maintaining industrial and laboratory electronic equipment. Worked in the manufacturing test area of several large electronics manufacturers for 10 years (advancing from technician to Supervisor). Built, rebuilt, and repaired computers. Have the usual equipment - wire cutters, screwdriver, jackknife, twiddle stick, soldering iron, desoldering iron, DVM, tube tester (not much call for that recently), oscilloscope (three of them, actually). I even have a mirror on a tripod stand so I can see the screen of a TV while sitting behind it.

Have you tried to examine the problem?
Taken the set back off?
Taken any readings or looked for obvious signs of the failure?
Roasted or burned parts, board discoloration?
Bloated capacitors?

Other than checking the fans, no. I've learned (the hard way) not to take things apart unless I'm confident I'll know what I'm looking for. That was the purpose of this thread.

Is the manual a paper document or a PDF? If PDF, can you provide us a copy?

I can do better than that (kinda). I've got the V33 chassis, here's a link to the V33Y/V33+ manual.

Pictures! We LIKE pictures!!

OK, here's one of a real cute baby!

PlainBill

[PlainBill]

Re: Mitsubishi DLP

Invite a person with good hearing and advise you on the potiential noise with this tv. particularly when turning on and running.

Color wheel is easy to do, just swapping out but price is kinda expensive. 120-150.

Cheers, Wizard

$120 - $150 sounds a lot better than the cost of the optical engine. I take it the 'ears' is supposed to be listening for some change in sound as the picture goes to heck? I can hear what is presumably the color wheel starting up within 10 seconds of turning the set on, but the sound disappears within a few seconds as it comes up to speed (I guess).

Thanks,

PlainBill

[Wizard]

Re: Mitsubishi DLP

It can be any kinds of noises. Squeal, groan, harsh whir etc. if it get bad. Eventually they fail to spin soon enough. Need some one to listen. I am deaf and I sometimes had to get someone to listen for me.

Cheers, Wizard

[Toasty]

Re: Mitsubishi DLP

Sounds like the bearings are dry and it's slowing down as it warms up. It's audible, but perhaps not by you.

[Toasty]

Re: Mitsubishi DLP

I apologize, I really didn't realize they used a mechanical device in this set.

Good grief, we've stepped back 50 years -

http://www.earlytelevision.org/colordaptor.html

Did you ever get a notice about a class action suit against Mitsubishi? It seems that there is something going on.

[Wizard]

Re: Mitsubishi DLP

And around 10,000 rpm on that little bitty 6 segment glass pieces held between hubs with glue and is about 2" dia appox or smaller, instead of 600 and few feet dia.

Agree with you. My eye can detect 60Hz on TVs with corner of eye and CRT monitors at 60Hz direct on so I had it 80Hz or higher. LCD at 60Hz is not a problem.
Colorwheel is BODGE, agreed. Rather have 3 DLP or LED DLP sets that switches colors rather faster than colorwheel does because I can detect rainbow effect with colorwheel DLP sets.

http://en.wikipedia.org/wiki/File:DL...bow_effect.JPG

http://cuviper.files.wordpress.com/2...p96-01103a.jpg

http://jdfaith.smugmug.com/photos/454534559_5ZEJc-L.jpg


Cheers, Wizard

[PlainBill]

Re: Mitsubishi DLP

I apologize, I really didn't realize they used a mechanical device in this set.

Good grief, we've stepped back 50 years -

http://www.earlytelevision.org/colordaptor.html

Did you ever get a notice about a class action suit against Mitsubishi? It seems that there is something going on.

No notice. From what I've seen in the various threads on the cnet and avs forums it's mainly posturing by a bunch of loudmouths with too much time on their hands.

There have been a couple of common faults that resulted in an extended warranty. In one case their vendor used the wrong kind of crimp connector (solid versus stranded wire) on a thermistor. This generated bogus 'air flow' warnings. I had that replaced under warranty. Also they've had a problem with the optical engine on the 73" DLP sets, but from what little I have heard, that failure has a much different appearance.

Overall, I am confident Mitsubishi has done a good job on designing this set. I've spent enough time working in manufacturing to know that often the first design has problems. And durability testing mechanical systems is a particular bitch. You can run a circuit board through an elevated temperature test and figure out which components are going to die first in the field. When it's a wheel spinning at 10000 rpm, it may have to spin 10,000,000,000 times before it becomes obvious the bearings aren't good enough.

PlainBill

[Toasty]

Re: Mitsubishi DLP

PB- Any progress?

[PlainBill]

Re: Mitsubishi DLP

PB- Any progress?

Nothing positive, unfortunately. By standing close to the TV set with the sound muted I can hear several 'spinning' sounds. A shortage of mature, (but still good) ears has hampered efforts to identify changes in the sound. I tried having my granddaughter help, but she can't hear anything that doesn't relate to Hannah Montana.

The next idea involves recording the sound using a computer and doing 'good' and 'bad' comparisons. That should reduce the human factor, but will have to wait on other demands of 'real life'. (In addition to being disabled with COPD, my wife feels I should be chief cook and bottle washer. My daughter-in-law is undergoing dialysis, so I am also babysitter to our 4 year old grandson and taxi driver for our 9 year old granddaughter when their mother isn't available. Added duties include garbage hauler, lawn boy, and computer repairman. Now my wife has decided to emulate Michelle Obama and plant a garden. Guess who is designated to prepare the soil and put in an irrigation system?) Before you feel too sorry for me, I'll tell you I just bought a 'dead' LCD TV on eBay, and am looking forward to fixing it's power supply.

I have investigated, but have failed to find a part number for the color wheel, let alone a source of same. What little information I can find indicates the light engine is not serviceable. The best price I can find for a rebuilt light engine ( 938P059020) is at Tri-State Module. $379 sounds better than $900 from UED, but without at least SOME clue that this will solve the problem, I'm reluctant to break open the wallet.

PlainBill

[Toasty]

Re: Mitsubishi DLP

Wizard >>Color wheel is easy to do, just swapping out but price is kinda expensive. 120-150.<<

Wizard will probably/should pop thru here now and give you the skinny on what the part number is and where to get it for those $$.

-AND-

You REALLY need to get to work. You just sound like you're lolly-gaggin' about the house. Idle hands are the playground.

[PlainBill]

Re: Mitsubishi DLP

Wizard >>Color wheel is easy to do, just swapping out but price is kinda expensive. 120-150.<<

Wizard will probably/should pop thru here now and give you the skinny on what the part number is and where to get it for those $$.

-AND-

You REALLY need to get to work. You just sound like you're lolly-gaggin' about the house. Idle hands are the playground.

I'm considering that. You've heard of the Chippendale Dancers? I want to start a similar group to entertain the ladies at the retirement communities. We'll be the 'Chunkendale Dancers'. Nobody under 60 or 225lbs in the group. Right now we're having problems finding Speedos in XXXL.

PlainBill

[Toasty]

Re: Mitsubishi DLP

LOL!

I think I know where I can find out...

When I hit the Boardwalk this summer, I ask some of the guys where they got them...

Need a lead on spandex? I can ask then too.