My first encounter with 2 seconds to black

[Th3_uN1Qu3]

So the Sammy i picked up for 50 bucks a couple months ago is going tomorrow for $92. That means i need a monitor.

Scanning my favorite auction site again (favorite because repair services advertised there are expensive so most people sell broken stuff rather than repair it), i stumbled upon a 19" Nec for $40 described as 2 seconds to black. I called the guy and he said a repair quote was $35 so he decided to sell it. Anyway, i'm picking it up tomorrow after parting with the Sammy. Let's see what i find inside. I'm hoping bad inverter, i really don't feel like swapping CCFLs.

There's also a 26" LCD TV that has been there for quite a while, with a bad backlight. But for $150 no way i'm touching that. For half that, maybe.

[alexanna]

Re: My first encounter with 2 seconds to black

The NEC's I have seen have been really high quality on the inside,CCfls are really fun to change.
Al.

[Th3_uN1Qu3]

Re: My first encounter with 2 seconds to black

CCfls are really fun to change.
Al.

I'm good with everything that doesn't involve taking the whole panel apart... reason being dusty environment. Been there, done that, not doing it again.

Anyway, someone is selling a fully working Benq G2222HDL (LED, 21.6", full HD) for $140 which seems a very good deal. Sure, 1920x1080 might be a tad cramped for this screen size but i'm used to small text so it should be alright. For what i do it should be damn near perfect. I'm real tempted to buy that one but we'll see.

[alexanna]

Re: My first encounter with 2 seconds to black

It might not be the ccfls.
I was just giving you some BULL ---poopy.
Al

[alexanna]

Re: My first encounter with 2 seconds to black

I'm good with everything that doesn't involve taking the whole panel apart... reason being dusty environment. Been there, done that, not doing it again.

Anyway, someone is selling a fully working Benq G2222HDL (LED, 21.6", full HD) for $140 which seems a very good deal. Sure, 1920x1080 might be a tad cramped for this screen size but i'm used to small text so it should be alright. For what i do it should be damn near perfect. I'm real tempted to buy that one but we'll see.

Well this Is a serious comment, Prices must really be expensive where you are.
Al.
AH crarp i missed the fully working part.

[Th3_uN1Qu3]

Re: My first encounter with 2 seconds to black

Yeah we sometimes tend to miss that side isn't it, since we're so used to fixing things. Anyway i decided to get thru uni exams first then bother about a new monitor... as it's likely a few more opportunities will come my way when i have more spare time. I read about the Benq that the colors suck so maybe the money will be better spent elsewhere.

Prices are expensive here, but not THAT expensive. It's salaries that are low.

[Th3_uN1Qu3]

Re: My first encounter with 2 seconds to black

Okay, got it in. Worked for a couple minutes then just brief flashes. It appears to be built quite solidly and although there are overheating marks on the PCB around the CCFL transformers and in the power supply section where the rectifiers are, they test fine. Caps are all Chemi-Con, all good.

So that leaves the CCFLs themselves. Well, that's the way it is sometimes. I'm still debating whether this is worth fixing or not... It's got a dust speck on the right side so the panel would have to be taken apart anyhow.

[alexanna]

Re: My first encounter with 2 seconds to black

Okay, got it in. Worked for a couple minutes then just brief flashes. It appears to be built quite solidly and although there are overheating marks on the PCB around the CCFL transformers and in the power supply section where the rectifiers are, they test fine. Caps are all Chemi-Con, all good.

So that leaves the CCFLs themselves. Well, that's the way it is sometimes. I'm still debating whether this is worth fixing or not... It's got a dust speck on the right side so the panel would have to be taken apart anyhow.

what did you get,NEC?
Brief flashes?
Al.

[Th3_uN1Qu3]

Re: My first encounter with 2 seconds to black

Yup, got a NEC Accusync 92vm. I meant brief flashes as in it flashes briefly when the power button is hit then goes dark. The classic 2 seconds to black. It ran a few minutes first time.

And i have good news and bad news now. The good: The inverter wasn't tripping any of its protections so i took a good look at the transformers and it didn't take me long to find several cracked joints on the 12v side of them. One of which had so little solder on, that it appears to have been that way from the factory! They were consistent with the heating pattern on the PCB.

Re-did those and the monitor is up and running. Now the bad news. The panel is dusty. Last time i took one apart to clean it i ended up with more dust after than before, but i'll take this one apart anyway and we'll see.

[alexanna]

Re: My first encounter with 2 seconds to black

I had an 18” NEC that I had to take the panel apart you might be surprised how easy it is.
I you have forced air heating and cooling try shutting it off when you're putting it back together.
Al.

[weirdlookinguy]

Re: My first encounter with 2 seconds to black

Go in the bathroom. Run the shower with some very hot water for a few minutes. Make sure things get really steamy. Then shut if off. Now go in there, shut the door tight, and feel free to take apart your monitor.

The humidity in the air will sink any dust particles floating in the air. This will give you a very clean environment to work in.

How does dust get inside an LCD to begin with?

[Th3_uN1Qu3]

Re: My first encounter with 2 seconds to black

The humidity in the air will sink any dust particles floating in the air. This will give you a very clean environment to work in.

Now that's a good idea. For another day.

How does dust get inside an LCD to begin with?

All my laptops have gotten dust inside them over time, one of them even had a couple specks since new. My theory is that they are always there in the screen but outside the viewing area, and with mechanical shocks, which happen all the time with laptops, they are knocked onto the screen.

I've encountered it less often in desktop screens but it still happens. As far as this one goes, judging by the amount of dust it had inside, i can easily see how some of that could have made its way on the screen, it didn't have to be there in the first place. LCDs aren't sealed, that's why CCFL replacement is possible. And dust will make its way into anything given enough time.

Oh and the VGA cable that came with it is absolute junk. I believe that it's not the original since it doesn't match the color scheme (it's white) and it has no ferrite beads on it. There's "smearing" and slight blurriness all over. I'll have to get a new cable. Besides that, i actually like this monitor. The internal speakers are actually useful because there's also a headphone connector on the front, something which is missing in my current speaker system. And it sounds decent too.

The inverter whines on this one as well (at least the CCFLs themselves don't whine like happened with the Samsung) but they designed it well and the whine is only audible when you are behind the monitor. No issue with using it the way it's intended to. Heavy shielding, lots of screws, quality components... it would be a keeper if i didn't need higher res. Mfg date is Jan 2005 btw. There's something that doesn't show up in the pics because it still had the yellow tape at that time - it's got these little rectangular clips over the CCFL connectors, to make sure they don't unclip by themselves! Something i really haven't seen before.

[mockingbird]

Re: My first encounter with 2 seconds to black

Wow, who said the NECs were high quality on the inside!? That looks like an Acer-style PSU.

So far, the best engineered LCD I've seen is the LG engineered Flatron L1710S which had a very impressive PSU.

Not that I'm encouraging buying LG stuff, some stuff they make themselves, and some stuff the contract out. And I had to change the Samxon GF junk on it... Oh yea, the image quality isn't better than the Viewsonic 17", but the colors are much mroe accurate. The red doesn't look orange.

[Th3_uN1Qu3]

Re: My first encounter with 2 seconds to black

At least it has coils and good quality capacitors. But it really really really needs a new signal cable.

[Th3_uN1Qu3]

Re: My first encounter with 2 seconds to black

I'm actually starting to like this thing. A lot. The seller also gave me the CD that came with the monitor and besides manuals and drivers (who needs that), it came with a piece of software that lets you control the monitor via DDC, no need to mess with the on-screen menus. Of course that software doesn't work on x64.

However there is another piece of software in there that works, which is a set of adjustment patterns with guidelines. As i said above, besides the smearing caused by the bad cable, the display also appeared blurry or out of focus in some areas. Tweaking the "fine" control would only move the affected areas around, it would not completely eliminate the problem.

I ran the adjustment software and followed the guidelines, and guess what. No more blurry areas! It turned out that the horizontal size setting was wrong, so the lines bunched together in some areas. Only the slight smearing is left now. Looks like the cable is so bad that it messes up auto adjustment and it has to be done manually. I'll go buy a new one on Monday.

[Th3_uN1Qu3]

Re: My first encounter with 2 seconds to black

I finally got around to buying a new cable today. And... hot damn. This thing is CRYSTAL clear now. Makes me even more determined to take it apart and clean the dust from inside.

[alexanna]

Re: My first encounter with 2 seconds to black

I finally got around to buying a new cable today. And... hot damn. This thing is CRYSTAL clear now. Makes me even more determined to take it apart and clean the dust from inside.

When you said dust inside the LCD I thought you were totally crazy.
Well I have just recently disassembled two LCD's to guess what------- remove some dust.
Have no idea how it got in there, It kinda looked like some dead pixels.
So I owe you a big thanks.
Al

[Th3_uN1Qu3]

Re: My first encounter with 2 seconds to black

Have no idea how it got in there, It kinda looked like some dead pixels.
So I owe you a big thanks.
Al

Don't mention it. Yes it does kinda look like dead pixels from a distance. And no i have no idea how it gets in there either - but given enough time, dust will get into anything, and this monitor wasn't cleaned too often by its previous owner so it had plenty of time to get in.

[alexanna]

Re: My first encounter with 2 seconds to black

Best of luck, mine look like new now!

[Th3_uN1Qu3]

Re: My first encounter with 2 seconds to black

Okay, i finally got man enough to take it apart. Fortunately, the dust was only between the TFT itself and the foil directly behind it. I did my best with Pronto antistatic spray and a "somewhat" clean cloth.

I've whipped it together quickly to see how i did, and i only have 3 tiny specks left. And they aren't black in color, just light gray, so they are only there if i look for them. Mission accomplished. Many thanks to alexanna for convincing me to get to it again, as my last LCD disassembly a few years back was a nightmare. I noticed that there are plenty of places for dust to creep in, i'll cover the sides of the LCD frame with tape to prevent that in the future.

A few pointers for anyone trying this: Before dismantling the panel clean EVERYTHING ELSE. Remove any adhesive strips, especially if they're old, they leave a lot of glue dust behind. Don't be afraid to handle the TFT layer, it won't break unless you try to. Don't just try to blow dust off, you'll get nowhere. Use a fine cloth and some antistatic household cleaner. You know, the stuff you normally use to clean screens. I don't have a "before" pic so an "after" won't mean much either, but take my word on it, i absolutely LOVE this screen now. It's a keeper.