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Old Feb 04, 2007, 01:12 PM
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Fixing V144 Inverter board.

Hi, Just in case any of you are still stuck with no backlights. I had the same fault on my cr@ppy chinese import LCD tv here in the UK (High street retailers own brand). I took it to work and scoped out the signals to find the overvoltage signal on Pin2 of the OZ960 chip was going slightly over the comparator threshold - 2.0 volts. To fix it I changed the value of the resistor connected to pin2 from 1M ohm (marked 105) to 100K ohm. Overvoltage signal is now reduced to 1.8-1.9 volt and the backlight stays on. IF YOU WISH TO TRY THIS DO SO AT YOUR OWN RISK the overvoltage protection is there for a reason - probably!

Arniewrx
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Old Feb 07, 2007, 08:30 AM
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Any Dead Darfon V144 Boards for Sale?

I've got an Audiovox FPE3000 with the same bad inverter problem. The inverter is definitely going into overvoltage protection. I checked all of the transformers for resistance, and one was a lot different than the others. The transformer primaries are wired as pairs, and when I moved both transformers in the pair the other lamps came on just fine.

So I would like to buy someone's dead Darfon V144 boards for parts.

BTW, I called LCDparts yesterday and they don't know when the replacement board is due in (the website says it will be available Feb 6, 2007).

If you are willing to sell your dead board, please send email to: neilrdavis@comcast.net. I'd gladly pay $100 for the board since I'm fairly confident it will help me fix the problem. Any more than that and I'd have to think about it.
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Old Feb 22, 2007, 08:53 PM
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Fixed the inverter board

Moniserv has the transformers in stock for the Darfon board. Just compare each one of them with an ohmeter and replace the oddball.

http://www.lcdpart.com/Products/v144.html
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Old Feb 23, 2007, 02:13 AM
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Great work Neil! I wish I did that when it first broken. I think the main chip on mine is dead. But can't find any information about it.
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Old Feb 23, 2007, 02:20 PM
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When testing these, can you tell me what post to test against? I was going to pick up a couple of the transformers for future need....
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Old Mar 01, 2007, 09:36 AM
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Quote:
Originally Posted by kuyote
When testing these, can you tell me what post to test against? I was going to pick up a couple of the transformers for future need....
To be honest with you, I didn't try to understand how the transformers were hooked up. I just compared the resistance of comparable legs with an ohmeter. Brute force--find the one that is different from the others. I just checked the primary--the two pins on the "bottom". The transformers are hooked up in pairs, and after removing both of them in the pair the other lights came on. I replaced the one bad transformer and all is well and we are using the TV again.

I did check pin 2 of the chip for overvoltage (greater than 2 volts), and it was clear that there was an overvoltage problem. You could probably check the voltage coming back from each leg and be more systemmatic about finding the bad transformer, but I didn't have the right schematic and just did the brute force approach.

Somebody had posted the O2Micro spec sheet on the chip, even though it is marked "confidential" on the first page and the notice on the last page says reproduction of the spec sheet is prohibited. Unfortunately, the wiring diagram that they show isn't like the Darfon board and isn't much help. I tried using that wiring diagram to help trace out the TV schematic, but gave up.
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Old Mar 17, 2007, 11:04 AM
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LT30HV Service Manual Posted at Yahoo Groups

Quote:
Originally Posted by Mike Kozlakowski
Although it's no consolation to those of us who own these units, I guess "˙ou get what you pay for" holds true in this case. I too tried tech support and gave up after half an hour on hold. I sent them an email (which they promise to answer within 24 hours) but of course heard nothing back. On the bright side, Thanh is getting his inverter repaired - we will see how that works out. I also found a source online which carries these new. Although not cheap, it's an option:

http://lcdpart.com/Products/v144.html

Syntax claiming they can't sell these is bs, it's a part made by a 3rd party (darfon) and used in a variety of lcd panels. They will just make more money if they do the repair. I think they've earned a little internet backlash. I would like to spread the word so to speak to teach them a lesson and to hopefully help them change their attitude toward their customers.

I've created a Yahoo Group for all us Olevia owners:

http://groups.yahoo.com/group/syntax_lcd

If anybody finds the inverters elsewhere for a better price, let us know.
Thanks for starting the newsgroup, which I joined. And thank you everyone for this excellent and useful discussion. I have been trying to find a way to get my LT30HV fixed and my search indicates that a lot of people are experiencing problems with their units after just two years.

I e-mailed Syntax and asked for a service manual and a part number for
the inverter. They sent me a copy of the service manual pdf file and
said I should get the inverter from the following link:
http://lcdpart.com/Products/v144.html

This link has been shared previously but its the first time that I
have heard about it coming from Olevia or Syntax-Brillian.

I have included the service manual in the "Files" section of the yahoo newsgroup at the following link:
http://f1.grp.yahoofs.com/v1/YPT7RZr...viceManual.pdf

I can also post it at this site but it exceeds the 3MB limit even when converted to a zip file.
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Old Mar 17, 2007, 12:16 PM
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Quote:
Originally Posted by BTL6434
...I have included the service manual in the "Files" section of the yahoo newsgroup at the following link:
http://f1.grp.yahoofs.com/v1/YPT7RZr...viceManual.pdf
Can you check this link? It comes back as file not found for me.
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Old Mar 29, 2007, 11:05 PM
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I also have a LT30HV and had the same problem. I sent my inverter board to lcdrepair.net to have them fix it. While my TV is now working I wouldn't recommend sending your board to them and I'll explain why. First of all I believe the website is backed by only one person who does the repair as well. My emails were never answered and neither were the voice mails I left. It was a rare occasion when I actually got through (happening twice in about 15 total attempts). What was also troubling was that my check (no method of electronic payment e.g. PayPal offered) was cashed right away and the repaired board didn't arrive until about 7 weeks afterwards! In addition the inverter board was shipped in a flimsy bubble envelope barely larger than the board via regular USPS ground mail (I found the board jammed into my mailbox!). Moreover, when I called an inquired about the status of my board I was told that it was already shipped. Then when I checked the postmark on the envelope it was actually shipped the day after I called, so apparently he lied to me. About the only positive was the cost was only $66 for the repair. Still though, if you have any electronic inclination I would recommend buying the transformer for lcdpart.com and doing the replacement yourself. I would have done this if I heard of part being available online early.

Anyways, now that I've properly vented , I'd like to thank Thanh for replying to my email and for posting his TV pics. The photos greatly helped in disassembling the unit. Also, I don't currently need it (but maybe for future use), thanks to the guy who posted the service manual.
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Old Mar 30, 2007, 09:48 PM
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Quote:
Originally Posted by Gary Warner
Can you check this link? It comes back as file not found for me.
Hi Gary, you need to join the yahoo group: syntax_lcd, then you can browse for the file in that group.

lbc13 I had bad service with lcdrepair.net as well. It tooked like 2+ months to get the inverter board back, which he didn't test it I think. At first he said he would test my board with a TV after he fixes it. When I called back complained that the fixed board doesn't work, he said he needed my TV sent in so that he could test it .

BTL6434 thanks for the service manual. Did you see the schematic of the inverter board? I looked at and it had schematic of everything but the inverter board. I saw some blank pages though, not sure what's wrong.

Meanwhile, I bought a new 40" Samsung 4041 LCD TV. It's big and nice, but one of the speakers has some rattiling noises when there are a lot of bass on the speaker! It sounds like something is not tighten correctly.

Thanh
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Old Apr 07, 2007, 12:27 PM
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I tried to attached the manual but the file is too large even when zipped.

Quote:
Originally Posted by Gary Warner
Can you check this link? It comes back as file not found for me.
Sorry for the late reply...

I don't know why there's a problem with the link. It worked when I first posted it. I can download at the yahoo groups "Files" section.
http://tech.groups.yahoo.com/group/syntax_lcd/files/ it still gives the error but if you right click and "Save Link" you can save to your hard drive (using Firefox).

This is the pdf file sent by the Syntax customer service rep.
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Last edited by BTL6434; Apr 07, 2007 at 12:38 PM. Reason: File too large.
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Old Apr 07, 2007, 12:52 PM
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I can see the schematics in my file.

Quote:
Originally Posted by thanhTran
Hi Gary, you need to join the yahoo group: syntax_lcd, then you can browse for the file in that group.

lbc13 I had bad service with lcdrepair.net as well. It tooked like 2+ months to get the inverter board back, which he didn't test it I think. At first he said he would test my board with a TV after he fixes it. When I called back complained that the fixed board doesn't work, he said he needed my TV sent in so that he could test it .

BTL6434 thanks for the service manual. Did you see the schematic of the inverter board? I looked at and it had schematic of everything but the inverter board. I saw some blank pages though, not sure what's wrong.

Meanwhile, I bought a new 40" Samsung 4041 LCD TV. It's big and nice, but one of the speakers has some rattiling noises when there are a lot of bass on the speaker! It sounds like something is not tighten correctly.

Thanh
Sorry for the late reply. I am using Adobe Reader 7.0.9 and all the schematics seem to be there (pages 40 to 61) but nothing specifically labeled inverter board. But the components appear to be there but I can't be certain since my background is minimal.
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Old Apr 08, 2007, 07:46 PM
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I have been reading your posts about getting the inverter board fixed. If your interest my father owns a TV repair shop in Chicago called Archer Electronics. The shop has been open for 15+ years. The number to the shop is 773-767-3653, if you have any questions just call and ask for Leszek. He has repaired these inverter boards in the past. The price for repair would be $150+shipping.
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Old Apr 23, 2007, 07:17 PM
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another dead Olevia

My Olevia has died after about 2 years. I did get a hold of the company and they told me the same thing. I told them they had better be careful and start taking care of their customers or they could get a class action lawsuit against them anyone know of any good lawyers?
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Old Apr 24, 2007, 02:50 AM
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A cool thing to do with LCD's after the inverters go out https://secure.lumenlab.com/shop/index.php?ref=& geared towards 15" LCD's but can be done with any size if you can find the lenses.

Dylan
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