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-   -   I need your guy's help. need any technical info available for Viewpia LCD TV's (http://www.videokarma.org/showthread.php?t=246332)

MRX37 10-26-2009 05:48 PM

I need your guy's help. need any technical info available for Viewpia LCD TV's
 
I would think, and I do hope that there's someone here who has access to some kind of technical information on Viewpia LCD TV's, particularly their 26 inch and larger models.

These TV's are sold over in the UK and europe, and they have a few things that can go wrong. Of particular interest to me is the failing to come out of standby, and the LED on the TV's front becoming very dim. I've searched on google for hours, and all i have found is people with questions, and no relevant answers.

I'm also trying to figure out how to access the service menu on a Viewpia LCD TV. The EURAS database seems to hold some answers for me, but of course I can't access it.

If anyone can provide me with any technical information, I would be very grateful.

andy 10-26-2009 06:40 PM

000

MRX37 10-26-2009 06:49 PM

Quote:

Originally Posted by andy (Post 2958245)
The first thing I would do is check the power supply for failing caps.

Trust me it ain't the power supply. That was my first guess, but swapping power supplies with a known good one does not fix the problem, but swapping the chassis board fixes it.

Also, even the worst new bad caps usually don't fail for at least a few months, these TV's could fail within a week.

karmaman 10-27-2009 12:34 AM

Check the surface-mount caps on the control board, SMD caps tend to get baked dry in LCD's. Also does this thing have a combo inverter/PSU board, or are they separate boards?

MRX37 10-27-2009 05:47 AM

Sorry, but I need actual technical information on this brand. I would love to take guesses at what's failing and troubleshoot with test equipment, but time constraints prohibit me from doing this.

And yes, it has a combo invertor/PSU board, but again the power supply is fine. Once the chassis board is replaced with a known good one, the TV has no more issues. The power supply powers it just fine.

The issue lies on the chassis board.

Zenith26kc20 10-27-2009 09:01 AM

Does this set have a large IC on the control board with no pins sticking out of the side? If it does, these are called ball grid array chips. If you look under the IC you can see the tiny solder balls but nothing can get to them. The heat from the IC can cause the no lead solder to crack and cause many problems. I have inquired as to repairing these and gotten some wild suggestions. I tried a heat gun and it fried the chip. Another that worked was to put the board in an oven at 400 degrees for around 15 minutes and that is supposd to reflow the solder. It has actually worked about 30% of the time.
The biggest problem is melting the plastic connectors.
ROHS.... designed with difficulty in mind!

andy 10-27-2009 09:49 AM

000

MRX37 10-27-2009 06:37 PM

Well, ANY technical information I can find out about these TV's will be of great use to me.

I'll level with you guys... I know more about these Viewpia sets then most of their customers overseas do. I know because where I work sells what are essentially these same TV's, only with our logo and a different casing. I found out about Viewpia through a goof up where one of our TV's had the user guide for a Viewpia in it

Now you would think we could just get all the technical info we needed straight from the manufacturer that makes these TV's for us... if you think that, you've never dealt with a Chinese TV manufacturer. Those assholes won't even give us the time of day, so we're on our own for technical info.

Quote:

Does this set have a large IC on the control board with no pins sticking out of the side? If it does, these are called ball grid array chips. If you look under the IC you can see the tiny solder balls but nothing can get to them. The heat from the IC can cause the no lead solder to crack and cause many problems.
[s]Oh yeah, these chassis boards have BGA chips on them...[/s] My mistake. These do NOT have BGA chips in them.

kc8adu 10-28-2009 07:30 AM

post pics of the boardset.
seems this set is sold under several names like spectroniq,ect

MRX37 10-28-2009 10:53 AM

This is the chassis board.

http://i33.tinypic.com/212d6he.jpg

The problem lies somewhere on this board. I just don't know where.

MRX37 10-29-2009 02:46 PM

Any ideas? Anyone?

zenithfan1 10-29-2009 03:25 PM

With as many surface mount parts it has, you might have to replace the board. Those 'lytics could be changed easy enough but the rest is not so easy. Ever tried hand soldering SMPs? Not fun at all. :no: The chips are impossible when the pins are so close together that there's only about .10 of an inch between them. There probably is a bad chip there somewhere too. Usually what goes on this kind of stuff. I guess in other words, check and replace what you can without wasting too much money on it. Good luck with it. :yes:

MRX37 10-29-2009 04:33 PM

Quote:

Originally Posted by zenithfan1 (Post 2958531)
With as many surface mount parts it has, you might have to replace the board. Those 'lytics could be changed easy enough but the rest is not so easy. Ever tried hand soldering SMPs? Not fun at all. :no: The chips are impossible when the pins are so close together that there's only about .10 of an inch between them. There probably is a bad chip there somewhere too. Usually what goes on this kind of stuff. I guess in other words, check and replace what you can without wasting too much money on it. Good luck with it. :yes:

Here's the deal. This is not just one TV. It's hundreds. Finding a solution will fix at least 10 of these right now.

I also found out today that these TVs are also sold by Pyle.

RobtWB 10-29-2009 04:48 PM

Just reviewed the entire thread.

You state -

Country of origin - China
Sets fail within a week
Hundreds of sets affected

OK - I'll be a smart a** - why bother with them???

Even if you were able to solve this particular problem, the re-failure rate of these sets has to be astronomically high.

mbates14 10-29-2009 05:07 PM

ive seen that exact controller IC used in numerous other LCD sets that I have worked on. its even heatsinked. the failure rate of that CPU control IC is low... so low that it isnt evne possible, however the vizios use the same IC and they DONT have a heatsink, but i find them failing an alarming rate becuase of lack of a heatsink, proper heatsinking problem never shows up.

In your case, i would vote out the main IC. what you need to do is monitor the on-board boost/buck switching regulators that pump out the proper core voltages for shorts and/or proper voltages. standby light is probably dim because there is a short in the rail on that main control module. ive delt with a couple of other brands with similar issues, and it turned out to be core regulator output transistors had failed.

keep an eye on these. And im also sure it goes without saying, in standby mode, check for excessive heating of any transistor, and obviously the CPU core. if the CPu gets abnormally hot then your done, only solution is to replace the board unless you can find a supplier in china for the IC, and usually these ICs have custom programming stored on the IC itself so your chances for that are none... And check your class-D audio output circuits for rail loading.


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