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Saturday, December 13, 2014

Tech question (Plus: An art joke. And sea urchins.)

So, my nice big monitor has gone totally blackscreen on me, and I do not have the funds to replace it. It's a little annoying to do Photoshop work the dinky backup monitor, but, like whatever.

Here's the thing: A number of YouTube videos convey the impression that monitor repair is easy. Just open 'er up, look for the bad capacitor (the cylindrical thingies), remove and solder a new one in place.

But what if all the capacitors look fine? Anyone out there know what to do next? (I know that the power supply is bad because I could see a very faint image on the lcd screen when I held a light right up next to it.)

Someone out there must be savvy enough to tell me what to do next. Thanks in advance!

The art joke: Actually, this is a true story. Salvador Dali and an artist friend attended an exhibition of abstract paintings. After a while, the friend asked Dali: "Why do you keep looking at that door over there?"

Dali answered: "Because it's the best-painted thing in here."

Salvador Dali tells this story in a book titled 50 Secrets of Magic Craftsmanship, which is full of useful, practical information for anyone in the trade. Some of his secrets are a bit odd, as you might expect. For example, he says that the oil painter's medium should include three decomposing wasps. I've never met anyone who has followed that advice, so I can't tell you if the wasps help. But Dali's paintings are in good condition, so I guess the wasps don't hurt.

He also says that dogs must be banished from the artist's studio; instead, the painter must keep a pet spider. Yeah, well...screw that.

The first secret is a bit complicated...
To begin with, you will eat three dozen sea urchins, gathered on one of the last two days that precede the full moon, choosing only those whose star is coral red and discarding the yellow ones. The collaboration of the moon in such cases is necessary, for otherwise not only do you risk that the sea urchins will be more empty but above all that they do not possess to the same degree the sedative and narcotic virtues so special and so propitious to your approaching slumber.* For the same reason these sea urchins should be eaten preferably in the spring—May is a good month.
It goes on and on like that. According to Dali, this meal puts one into a special slumber, and incredible dreams will come, and those dreams will inspire great paintings.Unfortunately, I don't know where one finds urchins around here, so I'm going to have to make do with Gorton's fish sticks. I'll let you know how it works.

And seriously, I need advice from someone who knows how to repair monitors. Can I do the job without a sea urchin...?

I repaired a Samsung TV myself. It was just a matter of searching for a YouTube video showing how to do it and then ordering the resistors and soldering gun from Amazon. Never buy a Samsung TV.
(Long - in 3 parts.)

Unfortunately, monitors can go black for a number of reasons; a bad capacitor is only one. That said, it's definitely worth looking into, as a dollar part and an hour's hassle could save you the cost of a replacement.

For a while, there was a very good chance your trouble was caused by a bad capacitor, as millions of monitors, televisions, computers, and other electronic devices ended up being damaged or destroyed as a result of perhaps the costliest instance of industrial espionage to date. (TL;DR version: Scientist steals a secret formula for electrolyte used in fluid-filled capacitors from his Japanese employer and takes it to China; later, his staff steal the formula from him and defect to Taiwan, where Taiwanese manufacturers use it to manufacture tens of millions of capacitors. Unfortunately, at some point the formula was mis-copied, leaving out an ingredient or two; the resulting capacitors are prone to bursting.) The resulting capacitor plague spread throughout all sectors of the electronics industry in the mid- to late-2000s, resulting in billions of dollars in damage and repair costs. (Dell alone spent $420 million to repair or replace motherboards.) Most devices manufactured after 2007, though, are unlikely to contain any of the faulty electrolyte, and a number of vendors transitioned to using only more-expensive solid capacitors in their designs. For the past few years, capacitor plague-related failures have been few anbd far between.

If your monitor dates from the plague years -- roughly 2003 through 2007 -- then you should definitely look into replacing your capacitors. (If yours is a plagued machine, you should go ahead and replace all of them.) You can probably find a kit containing all the capacitors your make and model of monitor requires, along with instructions, schematics, and an alligator clip heatsink, somewhere in the $12 to $20 range. Search eBay or the web for "[make] [model] capacitors." The last I checked, there were hundreds of such kits available.

Even if your monitor isn't of the right vintage, it's worth checking for a failed capacitor, as they aren't that uncommon even at the best of times. Fortunately, they call them 'blown capacitors' for a reason: A failed capacitor will often bulge, rupture, leak, or actually explode, making visual identification relatively simple. (Check your manual, though; if your monitor boasts 'all solid caps,' you won't be able to tell a bad capacitor by looking. Of course, if it boasts 'all solid caps,' you probably aren't dealing with capacitor failure.)

How easy they are to replace is another matter. If you're fortunate, the caps will be attached to the circuit board using what is known as 'through-hole soldering.' That's your standard, old-school PCB manufacturing technique: traces terminate in circular copper pads with a hole in the center; the component's leads are fed through the hole, soldered in place, and clipped. To replace such a component, you'll first need to desolder the old one. The easiest way to do so is to touch a piece of desoldering wick -- think of a tennis shoe lace woven from copper wires -- against the pad and then use a soldering iron to heat the solder joint through the wick; once the solder melts, it will be, um, wicked into the wick, freeing the old component and leaving the pad free of solder.

Almost forgot.

Tutorial on replacing surface-mount components.
Dali's art always seemed pretty trippy to me. I was thinking maybe mushrooms, but sea urchins never occurred to me (who knew?). The fish sticks could work if they were served with a side dish of fresh mushrooms of the proper variety.
As for sea urchins...get the to your nearest sushi bar and order uni. I think it tastes ghastly, myself, but it's a small sacrifice to make for the sake of art. Besides, the Japanese believe it's an aphrodisiac.
hmmm... did parts 2 and 3 not come through, or were they simply clipped for space? If the former, let me know and I'll re-up. Thanks.
Your monitor is dead because the backlight is dead. That's why you can see images on it when you aim a light at it.

Capacitors can hold a serious charge, in TVs and amps you don't dick around for fear of a serious shock.. tube amps'll kill you if you dick it up.

Unless you have some sort of stellar giant screen, it's probably not worth the expense. Sorry, but they're basically disposable.
"Your monitor is dead because the backlight is dead. That's why you can see images on it when you aim a light at it."

Yes, but it's probably *not* the light itself (often -- especially in larger monitors, as Joe has -- there are actually two backlight panels, so to have both go out at the same time is unlikely). Instead, it is probably either the power supply or the secondary power supply for the backlight -- which in turn could easily be caused by a blown capacitor or fuse.

"Capacitors can hold a serious charge, in TVs and amps you don't dick around for fear of a serious shock.. tube amps'll kill you if you dick it up."

The voltages in flat-screens are typically far lower than those for CRTs or plasma TV sets. LCD monitors with LED backlights *don't* have capacitors that would possibly hold dangerous voltages after the monitors is disconnected from mains power; ones with CCFL (cold-cathode fluorescent lamp) backlights *might* hold a charge after being disconnected, especially in sizes > 32". Even then, though, most flatscreen power supplies have drain resistors to bleed off the stored charge within minutes, and the ones without resistors will typically discharge after a few hours. If Joe has been using his backup monitor for days, with the main, now-dead, monitor unplugged, he'd be at little risk.

Of course, he could also play it safe and bleed the caps using a discharge resistor or bulb. There's information available on on how to do so.

"Unless you have some sort of stellar giant screen, it's probably not worth the expense. Sorry, but they're basically disposable."

Um, the cost for me to repair three $300 monitors was $1.80 apiece -- well, actually about $5 each, factoring in the cost of spare components and shipping. Yes, they're essentially disposable (and I can hear component manufacturers laughing all the way to the bank) *if* your only other option is to pay a service professional to make the repair---

---but, then, so are a lot of things.

I'm typing this on a Dell Dimension that for several years was my most powerful PC, with a Core 2 Duo processor and 4 Gb of RAM. I found it sitting on the curb at the end of the block. I booted it up and learned why the original owner most likely had dumped it: It was so painfully slow as to be essentially unusable. The fix? Install XP instead of the Vista it came with. (I assume it was probably heavily virus-laden, as well, but I didn't have the patience to find out.)

The repair took me all of 20 minutes (well, I probably did a full format of the drive, so the process took longer than 20 minutes, but I probably burned no more than 20 minutes of brain time), and it cost me nothing. (Over the years, I'd purchased 5 or 6 XP licenses; I reused the activation code from a P4 machine I had decommissioned in 2004.)

To the original owner, his PC was disposable. For me, it was a valuable secondary system that's given me a number of years of solid service.
maz, thank you so much, and I am sorry that I didn't respond earlier today. It's been kind of a busy day.

I don't see much reason to be fearful of capacitors, as long as the power is disattached. I've handled all sorts of mobos and graphics cards -- switching cases and that sort of thing.

Alas, all of those old caps in my monitor have not the slightest whisper of a hint of a bulge or anything else amiss.

Oh, and you are definitely right about the fact that folks are too quick to toss old equipment away. Some folks down the street trashed their entire system. I took it home and stripped the parts. Turned out the hard drive was beset my one nasty virus. I kept it well away from my own system. Wiped the drive and "washed" it with some heavy-duty anti-virus and anti-rootkit apps. Result: An extra 750 gigs.

Alas, I just don't think I can save this monitor. Well, I'm stuck in the 17-inch world until I can earn enough for something new.

Oh, and parts 2 and 3 did NOT go through, maz. Sorry!

One other thing I forgot to add: That "trashed" computer I found was later transformed into a nice duo-core system for a lady I know. Just popped in her old hard drive and loaded up the RAM and off she went. I can't imagine her ever needing more power.
How can I "wipe" my hard drive? I replaced a dead hard drive in my laptop and like a fool immediately picked up a persistent virus trying to download an overpriced book for free (sucker). Since there's nothing critical I need on that barely used drive I'd like to erase it completely so that I can just redo the clean install of Windows 7 and start over. But it can't reformat the entire disk because a partition needs to be reserved for enough of the operating system to run the computer to do the task. Only thing I've seen that would work is to get a second hard drive to run the system while the first is wiped. But if I'm buying another hard drive I'd probably just use it instead and toss the viral laden one.
Easy, CBarr. Install the drive as the only drive in a computer with an optical drive (CD, DVD). Then run a windows installation disc. There will be an option to reformat everything.

You can borrow an installation disc if you don't have one. Or, you know, the darker areas fo the net....
The windows installation disk I bought is supposedly for new installations only. I'd read that I couldn't run it and do a clean install if there was already an operating system on my hard drive. But I guess there's nothing to lose by trying. Thanks.
for completeness' sake...


If you aren't lucky, you'll be dealing with surface-mount technology, which is as literal a term as 'through-hole.' In such a case, component leads are attached to, not through, the pad -- which not only means they need to be clipped to a precise length before being attached, but component placement and clearance are likely to be tight, as surface-mount designs are usually intended to be assembled by an automated device rather than by hand. Fortunately, though, if you do need to replace a blown cap, there are limits to how small a capacitor can be and still be able to carry sufficient charge, so even surface-mount components tend to be human-scale. (More on that in a moment.)

You can find a lot of information on capacitor diagnosis and repair at; they also sell capacitors and capacitor kits and offer a repair-by-mail service.

You should also search the web for information on your monitor make and model, just to see if there are known common failures. For instance, ten years ago I bought four 19" ViewSonic VX900 monitors. (I think I paid $280 apiece for two and, liking them, went back to Fry's the following weelk (after the sale had ended) and bought two more at $320 a pop.) They came with a one-year warranty, but I later learned for some reason ViewSonic had decided to extend coverage to three years. Had I known, that might have helped me some when, thirty-five months later, one monitor went dark; at the time, though, I was only using three of them, so I swapped in the spare -- only to lose a second monitor six months later, and a third a month after that.

Not wanting to toss $900 worth of what had recently been perfectly good monitors -- especially as all were seemingly suffering from the same malady, I boxed them up and dragged them with me through my next couple of moves. (Had I been in a position to replace them, financially, I wouldn't have had to move.) Once I'd finally found some sort of fiscal equilibrium, thaks to the convergence of rent control and a DoD contact, I started to see if there was anything I might do to revive them.

I quickly learned the VX900's had a design flaw that often resulted in one or both of a pair of fuses blowing on the secondary power supply that feeds the fluorescent backlight. (Like most flatscreen monitors, the VX900 consists of an LCD panel lit from behind by a cold-cathode fluorescent panel.). This was well-known enough of a problem that third-party vendors were offering replacement invertors that could be swapped with the original boards with no soldering required. At about $50 each, they were a bargain compared to the cost of replacing a monitor -- but still a bit rich for my blood.


Fortunately, one of the companies that offered such replacements also hosted detailed, step-by-step instructions on repairing the original power supply. (Most likely this was in hopes that, once you saw what was required, you'd go ahead and buy their module.) At the time having more time than money (or brains), I decided to try my hand at repair, figuring if I couldn't get the originals to work, I'd still have the option of replacing them.

From a forum discussion at another site, I learned what amperage fuse was required and who sold them in small quantities. (Since surface-mount components are intended for use by robotic assemblers, they typically come packaged on reels of perforated tape, each component affixed to the tape individuallly, with anywhere from 1,000 to 10,000 components per reel.) I found a place offering them at $0.79 each. I ordered ten; with shipping, the total cost was around $15.

Remember how I said capacitors, at least, were constrained by the laws of physics as to how small they could become? Well, I wasn't dealing with capacitors, I was dealing with fuses -- and while I expect they, too, are limited to a minimum functional size, that minimum is several orders of magnitude smaller than those for capacitors. Just how small are we talking about? Take a look. That is a standard, unaltered Lincoln penny; the little green thing beside it the fuse. At each end of the fuse is a C-shaped area of silvery (white, in this photograph) metal: Those are the leads.

So, in order to repair a monitor, all I had to do was desolder the old, blown fuse and replace it with a new one, attaching each end to its own soldering pad, without overheatinjg the fuse or allowing solder either to touch the green part of the fuse or bridge the space between the two pads.


For each monitor.

As I recall, it took me about 15 hours, total: disassembling the monitor, replacing the fuses, reassembling the monitor, testing it, and repeating as necessary until all three were again functional. In the process, I lost one fuse and destroyed two more, leaving me with one to spare.

...which is a good thing, as one of my repaired monitors -- or perhaps it was the one that hadn't needed to be fixed -- recently went once more to black. It seems the problem with repairing, not replacing, the ViewSonic power supply is that doing so does nothing to alleviate the inherent design flaw, leaving the replacement fuses vulnerable to failure....

cbarr, if you just want to wipe the drive, you can use an old XP disc. Or you can make a system disc using any functioning Windows 7 system.

maz, I haven't read all of that yet, but...THANK YOU!
The IT support folks at my company use freeware KillDisk to wipe hard drives clean. I've also used it on my own PCs when they've become infected or just too bogged down with crap. KillDisk overwrites all the sectors with zeroes, which prevents recovery of any data. Then you just start again by installing the OS.
Fixing my Samsung didn't take 15 hours. Don't be discouraged by some of these horror stories.
Anonymous - My 15 hours wasn't a horror story; in fact, I was pretty damn pleased with myself. But mine wasn't a case of swapping out a blown, through-hole capacitor; instead, I had to replace two SMD fuses, each far smaller than a grain of rice, on each monitor. (To do so, I used one of those 'helping hands' jigs from Radio Shack with a mounted magnifying glass and a small LED flashlight in its claws pointed at the fuse. On top of that I wore a pair of 2x [3x?] reading glasses -- and even then I had to take regular breaks to rest my eyes.)

That 15 hours was to repair three monitors, as well -- and included the time it took to desolder and replace several fuses I'd managed to destroy.

I'd done some electronics repair work prior to attempting this repair -- oh, a total of maybe two dozen times in fifty years. Maybe three of those two dozen times my work didn't suck: I was an astoundingly crappy solderer. (I'm much better at it now.)

The important message to take away is this: If I managed to pull this off, *anyone* could do so.
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