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  #16  
Old 06-14-2016, 09:09 PM
Captainclock Captainclock is offline
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Originally Posted by mstaton View Post
I've had used boards that failed shortly after installation. I have also gotten boards from ebay that said they were tested and arrived with a blown fuse. And some boards will work for years. They fail because they are run at their limits and get very hot, Best not to try a chip replacement yourself the first time. I took me awhile to get it down without damage. It's not as straight forward as you may think. A bad or partially shorted screen of buffers on the verge of failure can also cause boards to fail. LG made buffers hold up better than Samsung buffers by far. Samsung buffers usually fail first and take out the Y-sus and then it becomes very expensive very fast.
IPM's usually fail with a large bang that immediately blows the fuse but the set will generally stay running. Usually only one goes bad but sometimes both go bad.
OK, well I guess I'll just have to try my luck with a used board from ebay and hope for the best, as I certainly can't afford nor justify spending over $100 to send the board in for repair to Coppel's TV Repair as suggested by one of the other members here, seeing as I would have more wrapped up into this unit than its worth then if I did that and wouldn't be able to make any money on the TV If I went to sell it, in fact I would be loosing money if I sold the TV at only $100 when I had over $120 into the unit, I'd rather make $40 than loose $20 when I went to sell the TV. So yeah, I'll just hope that the Y-Sustain Board doesn't go out when I get the replacement installed (although if its working when I sell it and it goes out on the next person who owns it, then its their problem and not mine.)
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  #17  
Old 06-15-2016, 07:11 AM
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dr.ido dr.ido is offline
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These old 42" Plasma sets rarely make more than $80 - $100 here.

LG Plasmas (and many other brands use LG panels) of this generation and earlier often have tired/worn out panels. You will still get a picture, but there will be random red dots everywhere that are very noticeable on dark scenes. Sometimes you can tweak them a bit and get a usable picture, sometimes there is no happy medium - Adjust far enough that the red go away (or at least are minimal) and you get dark dots on bright scenes.

IPM replacement is not easy. It's a multilayer board and the ground pins will soak up all the heat without budging. Preheating the board and low temp solder help.

I don't spend any money or much time on these kind of sets anymore - they're just not worth it. If I don't have a good used board available (that I pulled myself from another junked set, not from ebay) I don't bother.
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  #18  
Old 06-15-2016, 10:29 AM
Captainclock Captainclock is offline
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Originally Posted by dr.ido View Post
These old 42" Plasma sets rarely make more than $80 - $100 here.

LG Plasmas (and many other brands use LG panels) of this generation and earlier often have tired/worn out panels. You will still get a picture, but there will be random red dots everywhere that are very noticeable on dark scenes. Sometimes you can tweak them a bit and get a usable picture, sometimes there is no happy medium - Adjust far enough that the red go away (or at least are minimal) and you get dark dots on bright scenes.

IPM replacement is not easy. It's a multilayer board and the ground pins will soak up all the heat without budging. Preheating the board and low temp solder help.

I don't spend any money or much time on these kind of sets anymore - they're just not worth it. If I don't have a good used board available (that I pulled myself from another junked set, not from ebay) I don't bother.
I see, well I'll see what I can do with this unit anyways ('m not going to be selling it on here anyhow, I'll be selling it locally as I wouldn't trust shipping this TV with as big as it is.) I may even just keep it as a spare, as my LCD TV I have in my Bedroom that I got from my aunt has some dead pixels in it but otherwise good sound and picture so I could use this in place of my current unit once it goes bad completely.
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  #19  
Old 06-15-2016, 11:13 AM
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A little over a month ago, you faced the same dilemma with a Westinghouse 32 " set, where the cost of boards and other parts approached or surpassed the value of the set.... how did that work out for you?

jr
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  #20  
Old 06-15-2016, 01:04 PM
Captainclock Captainclock is offline
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Originally Posted by jr_tech View Post
A little over a month ago, you faced the same dilemma with a Westinghouse 32 " set, where the cost of boards and other parts approached or surpassed the value of the set.... how did that work out for you?

jr
Well I'm just going to pitch that westinghouse tv unless I can find a replacement board for the TV for super cheap on ebay, which it wasn't that the parts were extremely expensive it was that they didn't have any of the boards for sale on ebay at the time and I didn't want to invest in an ESR meter to try and figure out which caps in the power supply/inverter board were bad because yes a bare naked ESR Meter is only $15 on ebay, what scared me the most about those meters is that I could accidently short it out. Anyways, if this would of been a CRT TV it would of been more worth fixing I think, it seems that the flatpanel TVs tend to be like brand new cars where they lose half their value immediately after you buy it, whereas CRT TVs seemed to of kept more of their value over time.

And the biggest problem is that with these flat panels is that its hard to know whether or not they'll be worth fixing or not unless you take them apart and get a good look at the insides and when I see a Flat Panel in the salvage bin at work its not like they're gonna let me take the TV apart to see if its got blown capacitors in the power supply before I buy it off the salvage to see if I want to buy it or not, that's kind of what the repair business is all about, though isn't it, you're taking a chance that something may or may not be worth fixing to sell, its not just flat panel TVs that are that way, but also the old CRT TVs are that way as well and so are the old radios, when you buy something that's in unknown working order to fix it up and resell it, you're taking a chance that it may turn out to be a piece of junk that's not worth your time.

Last edited by Captainclock; 06-15-2016 at 02:52 PM.
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  #21  
Old 06-17-2016, 12:52 PM
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Originally Posted by Captainclock View Post
I didn't want to invest in an ESR meter to try and figure out which caps in the power supply/inverter board were bad because yes a bare naked ESR Meter is only $15 on ebay, what scared me the most about those meters is that I could accidently short it out.
If that is your main concern, for only a few dollars more, you can get one in a fairly basic looking plastic box:

https://www.amazon.com/SainSmart-Poc...ords=esr+meter

Or a nicer looking box wih some handy short clip leads:

https://www.amazon.com/Huhushop-Tran...ords=esr+meter

Either one of these, properly used, should substantially improve your chances of finding bad caps on these sets... bulged and oozing appearance does *not* tell the whole story.

just my 2 cents,
jr
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  #22  
Old 06-17-2016, 03:18 PM
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Quote:
Originally Posted by jr_tech View Post
If that is your main concern, for only a few dollars more, you can get one in a fairly basic looking plastic box:

https://www.amazon.com/SainSmart-Poc...ords=esr+meter

Or a nicer looking box wih some handy short clip leads:

https://www.amazon.com/Huhushop-Tran...ords=esr+meter

Either one of these, properly used, should substantially improve your chances of finding bad caps on these sets... bulged and oozing appearance does *not* tell the whole story.

just my 2 cents,
jr
Being an impatient cheapskate I paid $5 more than the (2 month shipping time ) Asian sellers were asking for a bare board that had fast shipping...Then I made my own box from a piece of plexiglass leftover from my college senior design project. Mine gets exposed to steel wool fibers etc. and has never shorted or been damaged in the year + I've had it...Granted my case does a decent job keeping that crap out.
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  #23  
Old 06-17-2016, 05:24 PM
Captainclock Captainclock is offline
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I'll admit that I probably should invest in one of those ESR Meters, but then again like I said if its only 15-20 dollars you're probably going to be paying for something that's of poor quality build wise because that's usually the way it is in the electronics world, the cheaper the price is, the lesser the build quality and thus the more likely it is that it will be dead in about a year or 2.

Well I broke down and ordered an ESR Meter, and its was one that was in a case already. it was $35 but I figured it would be worth it, because it also had Mosfet, Transistor and resistor tests on it as well besides ESR Tests for Capacitors and it can test capacitors in circuit. And Jr. Tech, the ESR Meter I ended up getting was the one that was in the second link you posted in your post on here.

Last edited by Captainclock; 06-17-2016 at 05:38 PM.
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  #24  
Old 06-18-2016, 12:51 PM
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I suspect that you will be pleased when you discover all that the tester can do. If you have not seen it yet, here is a link to a YouTube video of a short demonstration:

https://m.youtube.com/watch?v=b3dPBnYixs4

Contrary to his opinion, I find the ZIF (zero insertion force) socket to be very useful... about a month ago I went through a bunch of random semiconductor devices that were just thrown into a coffee can over the years and sorted out npn, pnp, fets, scrs, thyristors, diodes... very useful device!

Here is a pdf by the original desiger... likely more than most need to know, but an interesting read nonetheless:

http://www.mikrocontroller.net/attac...er_eng104k.pdf

jr

Last edited by jr_tech; 06-18-2016 at 01:01 PM. Reason: add second link
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  #25  
Old 06-18-2016, 05:32 PM
Captainclock Captainclock is offline
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Originally Posted by jr_tech View Post
I suspect that you will be pleased when you discover all that the tester can do. If you have not seen it yet, here is a link to a YouTube video of a short demonstration:

https://m.youtube.com/watch?v=b3dPBnYixs4

Contrary to his opinion, I find the ZIF (zero insertion force) socket to be very useful... about a month ago I went through a bunch of random semiconductor devices that were just thrown into a coffee can over the years and sorted out npn, pnp, fets, scrs, thyristors, diodes... very useful device!

Here is a pdf by the original desiger... likely more than most need to know, but an interesting read nonetheless:

http://www.mikrocontroller.net/attac...er_eng104k.pdf

jr

OK so when measuring a capacitor's ESR rating what kind of measurement should I be getting if the capacitor is good, and what kind of reading should I get if the capacitor is bad? I'm wondering because I'm going to see If I can take another crack at that Westinghouse TV.
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  #26  
Old 06-18-2016, 06:35 PM
andy andy is offline
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Last edited by andy; 12-07-2021 at 04:18 PM.
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  #27  
Old 06-18-2016, 06:51 PM
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Depends on the size, voltage rating of the capacitor and quality of the capacitor, but lower esr is better. I printed out this scale as a guideline, and find it useful.

http://www.electro-tech-online.com/a...003-jpg.84737/

It is also useful to compare readings to those taken on a new good quality capacitor of the same size and voltage rating. On large capacitors, say under one tenth of an ohm or lower, you may need to zero out or just subtract the test lead resistance to get a better reading.

jr
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  #28  
Old 06-19-2016, 02:42 PM
Captainclock Captainclock is offline
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Originally Posted by jr_tech View Post
Depends on the size, voltage rating of the capacitor and quality of the capacitor, but lower esr is better. I printed out this scale as a guideline, and find it useful.

http://www.electro-tech-online.com/a...003-jpg.84737/

It is also useful to compare readings to those taken on a new good quality capacitor of the same size and voltage rating. On large capacitors, say under one tenth of an ohm or lower, you may need to zero out or just subtract the test lead resistance to get a better reading.

jr
OK, so which leads should I use on the ESR meter to test the Capacitors? It has 3 leads a red, yellow and a green lead, and I'm assuming that I just need to use 2 of the 3 leads for the ESR test.
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  #29  
Old 06-19-2016, 03:30 PM
Captainclock Captainclock is offline
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Well I think I might of found one of the faulty capacitors in the westinghouse TV that was causing it not to power on, it was a 150MFD 450V electrolytic capacitor that measured at about 135 MFD and ESR measured at a whopping 8.5 ohms. So I think that might of been why the TV wasn't powering on considering it was the main filter cap for the power supply, at least I think that's what it is.

EDIT: I retested the capacitors again, and there were a few capacitors that did actually test off from where they should of been, so it seems I will have to replace some capacitors on the power supply board for the westinghouse tv.
C46, C45, C59, C49, C11, C69, and C17 are the ones that measured unacceptable.

Last edited by Captainclock; 06-19-2016 at 05:10 PM.
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  #30  
Old 06-19-2016, 07:01 PM
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Originally Posted by andy View Post
Bad caps typically have 10-100 times the normal ESR. A cap that's just a little high in ESR usually won't stop something from working, but it may be a sign that it's close to the end of its life.
Be sure to keep this in mind... the chart that I linked to above is typical for new caps, some increase is normal over useful life. Caps that have 10 times or more than typical new value are suspect.
I have even seen new (cheap) caps that were about 2 times the value stated on the chart and they seemed to work ok, while higher quality brands usually beat the chart number by a significant margin.

jr
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