DIY repair of monitors samsung 2380

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• t.iva
• New member
• Inactive

• Registered: 2015-12-29
• Posts: 2

Good day! Monitor - Samsung, SyncMaster F2380. In 2013, by accident, I broke off the screen menu buttons at the bottom of the monitor https://my.housecope.com/wp-content/uploads/ext/1921/storage/0/8/1/QFUcJ8 ... 060081.jpg, but the menu worked, there were no problems, although I did not use the on-screen menu at all. At the beginning of December 2015, all of a sudden my screen menu pops up, I didn’t touch the buttons at all and it didn’t disappear, pressing the “menu” button it disappeared for 1 second and reappeared. I took the monitor to the service center, where they told me that I broke the buttons, and the menu pops up because of that. They repaired it, for 50 hryvnyas, according to their words, the problem was in the buttons. Two weeks later, when I went to the computer in the morning, the screen showed that there was no signal, I disconnected the cables, doing this a couple of times with the PC rebooting, the monitor turned on, but started to go out every 5 seconds, but you can work on the PC, it looks like this ... I will be glad to answer.

• 
• Sarmat_134rus
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• Where: RF
• Registered: 2014-12-23
• Posts: 449

t.iva (Taras) the monitor must be disassembled and the swollen conduits should be looked at, it has a built-in power supply unit. It is possible to meet some joint. I almost wrote about backlight lamps

- after all, the monitor is LED-ovsky

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• Kakhovich Andrey
• Administrator
• Inactive

• Where: Ukraine
• Registered: 2013-01-18
• Posts: 2,163

There was one such monitor (the menu was not removed at all). They removed the panel, cleaned the button, re-soldered the contacts, it seems to work. And what is happening to him now. find it difficult to answer.

• t.iva
• New member
• Inactive

• Registered: 2015-12-29
• Posts: 2

I handed it over to the Samsung service center, repaired it, and took it right that day, paid 220 UAH. When I came to pick up the person who did it, it wasn’t already, and according to the girl who gave me the monitor, the problem was in the buttons, but I couldn’t explain anything else. Thanks for answers!

It so happened that once the screen of the Samsung 740N monitor, which has faithfully served me for almost 11 years, suddenly went out almost immediately after turning it on. Other attempts to enable and disable were unsuccessful, because according to the signals from the sound card, the operating system was booted successfully, it became clear that the problem lies in the monitor. Of course, a radio amateur cannot so easily throw out an old electronic device without trying to fix it, well, or raskurochit broken device for parts, then how it goes.

A quick search [1-6] showed that the most common problem with monitors of this type is the failure of electrolytic capacitors in the power supply. In general, even the most novice radio amateur can do such repairs, so you can get by with the purchase of several radio components at the place of purchase of the monitor, which is a couple of orders of magnitude cheaper, the cost of your own time, of course, is not taken into account. But in order to repair something, you first need to get inside the monitor, do it carefully, without marks on the case, perhaps the most difficult part of the repair. First you need to put the monitor face down, so that the surface of the screen would not be damaged, after that you should unscrew the screws holding the stand.

The back cover of the monitor is held by latches located around the perimeter of the monitor case. To open the latches, insert a strong thin object, such as an unnecessary plastic card or a metal ruler, into the gap between the screen frame and the back cover, and then sequentially and slowly unscrew all the latches holding the cover. Under the back cover, such a spectacle appears before us.In the next photo, the cover that covers the power connectors of the backlight lamps is also removed.

It should be noted that the metal casing visible in the photo above, to which most of the structural elements are attached, is fixed in the desired position with the help of the back cover and is not fixed to anything else. Before further disassembling the monitor, carefully document the wiring of all internal connectors. True, a real chance to confuse the connectors exists only for the power connectors for the backlight lamps.

Just in case, we fix the position of the remaining connectors.

Now, from the actual screen, you can remove the casing with the printed circuit boards fixed in it.

Then we remove the power supply board.

As expected, three failed electrolytic capacitors are visible on the board.

Finally, we disconnect the power supply board and remove the protective film that covers the board from the side of the printed conductors, this film is held on 3 plastic clips.

In addition to the obviously failed capacitors, a number of sources reviewed recommend replacing the C107 capacitor for preventive purposes.

This radio part has been replaced with a 47 μF x 250 V capacitor.

Just as the reviewed sources indicated, the fuse F301 breaks down along with the capacitors. In the photo, this is a green radio component, which is visible next to the swollen electrolytic capacitors.

We remove suspicious and clearly damaged radio components from the board. The main culprits are that the author of these lines was left without a computer on May 9, 2017.

In place of the failed radio components, we install similar capacitors. Instead of a 3 A fuse, a 3.15 A fuse with solder leads is installed.

After assembly, the monitor's performance was fully restored, after three weeks of intensive use, no deviations were noticed in the work. The author of the material is Denev.

It has no screws, but I don’t understand in what sequence to disassemble .. first, the frame, around the matrix to tear off, apparently.

Is it easier to break a monitor during disassembly than a laptop? I remembered something about its price. And it became scary.

If only there were disassembly instructions.

Haha. And I figured it out !! I'm really pleased with myself. the first monitor disassembled and reassembled.

And I immediately had a question: There are 2 boards and the matrix itself.

1) 2 boards are interconnected by wires. Can these wires be lengthened ??

2) The boards are connected to the matrix with wires to the backlight (as far as I understand) and to the screen.

Is it possible to lengthen the wires that supply the backlight?

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Is your TV, radio, mobile phone or kettle broken? And you want to create a new topic about this in this forum?

First of all, think about this: imagine that your father / son / brother has an appendicitis pain and you know from the symptoms that it is just appendicitis, but there is no experience of cutting it out, as well as the tool. And you turn on your computer, access the Internet on a medical site with the question: "Help to cut out appendicitis." Do you understand the absurdity of the whole situation? Even if they answer you, it is worth considering factors such as the patient's diabetes, allergies to anesthesia and other medical nuances. I think no one does this in real life and will risk trusting the life of their loved ones with advice from the Internet.

The same is in the repair of radio equipment, although of course these are all the material benefits of modern civilization and in case of unsuccessful repairs, you can always buy a new LCD TV, cell phone, iPAD or computer. And for the repair of such equipment, at least it is necessary to have the appropriate measuring (oscilloscope, multimeter, generator, etc.) and soldering equipment (hairdryer, SMD-hot tweezers, etc.), a schematic diagram, not to mention the necessary knowledge and repair experience.

Let's consider a situation if you are a beginner / advanced radio amateur soldering all sorts of electronic gizmos and having some of the necessary tools. You create an appropriate thread on the repair forum with a short description of “patient symptoms”, ie.for example “Samsung LE40R81B TV does not turn on”. So what? Yes, there can be a lot of reasons for not switching on - from malfunctions in the power system, problems with the processor or flashing firmware in the EEPROM memory.
More advanced users can find the blackened element on the board and attach a photo to the post. However, keep in mind that you are replacing this radio element with the same one - it is not yet a fact that your equipment will work. As a rule, something caused the combustion of this element and it could “pull” a couple of other elements along with it, not to mention the fact that it is quite difficult for a non-professional to find a burned-out m / s. Plus, in modern equipment, SMD radio elements are almost universally used, soldering which with an ESPN-40 soldering iron or a Chinese 60-Watt soldering iron you risk overheating the board, peeling tracks, etc. The subsequent restoration of which will be very, very problematic.

The purpose of this post is not any PR of repair shops, but I want to convey to you that sometimes self-repair can be more expensive than taking it to a professional workshop. Although, of course, this is your money and what is better or more risky is up to you.

If you nevertheless decide that you are able to independently repair the radio equipment, then when creating a post, be sure to indicate the full name of the device, modification, year of manufacture, country of origin and other detailed information. If there is a diagram, then attach it to the post or give a link to the source. Write down how long the symptoms have been manifesting, whether there were surges in the supply voltage network, whether there was a repair before that, what was done, what was checked, voltage measurements, oscillograms, etc. From a photo of a motherboard, as a rule, there is little sense, from a photo of a motherboard taken on a mobile phone there is no sense at all. Telepaths live in other forums.
Before creating a post, be sure to use the search on the forum and on the Internet. Read the relevant topics in the subsections, perhaps your problem is typical and has already been discussed. Be sure to read the article Repair strategy

The format of your post should be as follows:

Topics with the title “Help fix the Sony TV” with the content “broken” and a couple of blurred photos of the unscrewed back cover, taken with the 7th iPhone, at night, with a resolution of 8000x6000 pixels are immediately deleted. The more information you post about the breakdown, the more chances you will get a competent answer. Understand that the forum is a system of gratuitous mutual assistance in solving problems and if you are dismissive of writing your post and do not follow the above tips, then the answers to it will be appropriate, if anyone wants to answer at all. Also note that no one should answer instantly or within a day, say, no need to write after 2 hours “That no one can help”, etc. In this case, the topic will be deleted immediately.
You should make every effort to find a breakdown on your own before you get stumped and decide to go to the forum. If you outline the entire process of finding a breakdown in your topic, then the chance of getting help from a highly qualified specialist will be very great.

If you decide to take your broken equipment to the nearest workshop, but do not know where, then perhaps our online cartographic service will help you: workshops on the map (on the left, press all buttons except “Workshops”). You can leave and view user reviews for workshops.

For repairmen and workshops: you can add your services to the map. Find your object on the map from the satellite and click on it with the left mouse button. In the field “Object type:” do not forget to change to “Equipment repair”. Adding is absolutely free! All objects are checked and moderated. A discussion of the service is here.

Here are the TOP 10 most common LCD monitor malfunctions that I felt the hard way. The fault rating was compiled according to the author's personal opinion, based on the experience of working in the service center.You can take this as a universal repair manual for almost any LCD monitor from Samsung, LG, BENQ, HP, Acer and others. Here we go.

I divided the malfunctions of LCD monitors into 10 points, but this does not mean that there are only 10 of them - there are many more, including combined and floating ones. Many of the breakdowns of LCD monitors can be repaired by hand or at home.

in general, although the power indicator may be blinking. At the same time, twitching the cable, dancing with a tambourine and other pranks do not help. Tapping the monitor with a nervous hand usually doesn't work either, so don't even try. The reason for such a malfunction of LCD monitors is most often the failure of the power supply board, if it is built into the monitor.

Recently, monitors with an external power source have become fashionable. This is good because the user can simply change the power supply in the event of a breakdown. If there is no external power source, then you will have to disassemble the monitor and look for a malfunction on the board. In most cases, it is not difficult to disassemble an LCD monitor, but you need to remember about safety.

Before fixing the poor fellow, let him stand for 10 minutes, unplugged. During this time, the high-voltage capacitor will have time to discharge. ATTENTION! DANGEROUS TO LIFE if the diode bridge and the PWM transistor burn out! In this case, the high voltage capacitor will not discharge in an acceptable time.

Therefore, EVERYONE before repairing to check the voltage on it! If a dangerous voltage remains, then the capacitor must be manually discharged through an insulated resistor of about 10 kOhm for 10 seconds. If you suddenly decide to close the terminals with a screwdriver, then keep your eyes away from sparks!

Next, we proceed to inspect the monitor power supply board and change all burned-out parts - these are usually swollen capacitors, blown fuses, transistors and other elements. It is also MANDATORY to solder the board or at least inspect the soldering under a microscope for microcracks.

From my own experience I will say - if the monitor is more than 2 years old - then 90% that there will be microcracks in the soldering, especially for LG, BenQ, Acer and Samsung monitors. The cheaper the monitor, the worse it is made at the factory. Up to the point that the active flux is not washed out - which leads to the failure of the monitor after a year or two. Yes, yes, just when the guarantee ends.

when the monitor is turned on. This miracle directly indicates to us a malfunction of the power supply.

Of course, the first step is to check the power and signal cables - they must be securely fastened in the connectors. A blinking image on the monitor tells us that the monitor backlight voltage source is constantly jumping off the operating mode.

The most common reason for this is swollen electrolytic capacitors, microcracks in the solder and a faulty TL431 microcircuit. Swollen capacitors most often cost 820 uF 16 V, they can be replaced with a larger capacity and a higher voltage, for example, the cheapest and most reliable ones are Rubycon 1000 uF 25 V capacitors and Nippon 1500 uF 10 V capacitors. 105 degrees) Nichicon 2200 uF 25 V. Everything else will not last long.

after the time has elapsed or does not turn on immediately. In this case, again, there are three frequent malfunctions of LCD monitors in order of frequency of occurrence - swollen electrolytes, microcracks in the board, faulty TL431 microcircuit.

With this fault, a high-frequency squeak of the backlight transformer can also be heard. It usually operates at frequencies between 30 and 150 kHz. If the mode of its operation is violated, oscillations can occur in the audible frequency range.

but the image is viewed under bright light. This immediately tells us about a malfunction of LCD monitors in terms of the backlight. In terms of the frequency of occurrence, it could be put in third place, but it has already been taken there.

Option two - either the power supply and inverter board burned out, or the backlight lamps are faulty. The latter reason is not common in modern monitors with LED backlighting. If the LEDs are backlit and fail, then only in groups.

In this case, there may be a darkening of the image in places at the edges of the monitor. It is better to start repairs with diagnostics of the power supply and inverter. An inverter is the part of the board that is responsible for the formation of a high-voltage voltage of the order of 1000 volts to power the lamps, so in no case should you try to repair the monitor under voltage. You can read about repairing the Samsung monitor power supply in my blog.

Most monitors are similar in design, so there shouldn't be any problems. At one time, monitors simply rained down with a breakdown in contact near the tip of the backlight. This is treated with the most careful disassembly of the matrix to get to the end of the lamp and solder the high voltage wires.

If the backlight itself burns out, I would suggest replacing it with the LED backlight bar that usually comes with your inverter. If you still have questions - write to me by mail or in the comments.

These are the nastiest LCD monitor malfunctions in the life of any computer technician and user, because they tell us that it's time to buy a new LCD monitor.

Why buy new? Because your pet's matrix is ​​90% unusable. Vertical stripes appear when the contact of the signal loop with the contacts of the matrix electrodes is broken.

This can only be cured by careful application of anisotropic adhesive tape. Without this anisotropic glue, I had a bad experience repairing a Samsung LCD TV with vertical stripes. You can also read how the Chinese repair such strips on their machines.

An easier way out of this unpleasant situation can be found if your brother-in-law friend has the same monitor lying around, but with faulty electronics. It will not be difficult to blind from two monitors of similar series and the same diagonal.

Sometimes even a power supply unit from a monitor with a larger diagonal can be adapted for a monitor with a smaller diagonal, but such experiments are risky and I do not recommend starting a fire at home. Here in someone else's villa - that's another matter ...

Their presence means that the day before, you or your relatives had a fight with the monitor because of something outrageous.

Unfortunately, household LCD monitors do not provide shockproof coatings and anyone can offend the weak. Yes, any decent poke with a sharp or blunt object into the LCD monitor matrix will make you regret it.

Even if there is a small trace or even one broken pixel, over time, the spot will begin to grow under the influence of temperature and voltage applied to the liquid crystals. Unfortunately, it will not work to restore the dead pixels of the monitor.

That is, there is a white or gray screen on the face. First, you should check the cables and try connecting the monitor to a different video source. Also check if the monitor menu is displayed on the screen.

If everything remains the same, we look closely at the power supply board. In the power supply unit of the LCD monitor, voltages of 24, 12, 5, 3.3 and 2.5 volts are usually formed. It is necessary to check with a voltmeter if everything is in order with them.

If everything is in order, then we carefully look at the video signal processing board - it is usually smaller than the power supply board. It has a microcontroller and auxiliary elements. You need to check if food comes to them. With one probe, touch the contact of the common wire (usually along the contour of the board), and with the other, go over the terminals of the microcircuits. Usually food is somewhere in the corner.

If everything is in order in the power supply, but there is no oscilloscope, then we check all the monitor loops. There should be no carbon deposits or darkening on their contacts. If you find something, clean it with isopropyl alcohol. In extreme cases, you can clean it with a needle or scalpel. Also check the ribbon cable and the board with the monitor control buttons.

If all else fails, then perhaps you are faced with a case of a failed firmware or a failure of the microcontroller. This usually happens from surges in the 220 V network or simply from aging of the elements. Usually, in such cases, you have to study special forums, but it's easier to start up for spare parts, especially if you have a familiar karate fighter fighting against objectionable LCD monitors.

This case is easily treated - you need to remove the frame or the back cover of the monitor and pull out the board with buttons. Most often, there you will see a crack in the board or in the solder.

Sometimes there are faulty buttons or a loop. A crack in the board violates the integrity of the conductors, so they need to be cleaned and soldered, and the board must be glued to strengthen the structure.

This is due to aging of the backlight lamps. According to my data, LED backlighting does not suffer from this. Deterioration of the parameters of the inverter is also possible due to aging of the constituent components.

This is often due to a bad VGA cable without an EMI suppressor - a ferrite ring. If replacing the cable does not work, then power supply interference may have entered the imaging circuits.

Usually they get rid of them schematically by using filtering capacities for power supply on the signal board. Try to replace them and write to me about the result.

This completes my wonderful rating of the TOP 10 most common LCD monitor malfunctions. Most of the breakdown data is collected from repairs of popular monitors such as Samsung, LG, BENQ, Acer, ViewSonic and Hewlett-Packard.

This rating, it seems to me, is also true for LCD TVs and laptops. What is your situation on the LCD monitor repair front? Write on the forum and in the comments.

The most common questions when disassembling LCD monitors and TVs - how to remove the frame? How do I release the latches? How to remove the plastic from the case? etc.

One of the wizards made a nice animation explaining how to disengage the latches from the chassis, so I'll leave it here - it will come in handy.

To view animation - click on the image.

Recently, monitor manufacturers are increasingly completing new monitors with external power supplies in a plastic case... I must say that this makes it easier to troubleshoot LCD monitors by replacing the power supply. But it complicates the operating mode and the repair of the power supply itself - they often overheat.

I showed how to disassemble such a body in the video below. The method is not the best, but it is fast and can be done with improvised means.

NCC-1701-A / 24-12-2009, 20:32
Hello.

Link
/ hardware / monitors / 27237 I studied and UNDERSTOOD the principle of operation of C-PVA (I have a similar principle on my Canon SX110 camera - it shows cool, though it was not Samsung who made it (matrix), but most likely Sharp).
Hence it follows that C-PVA is generally a new type of matrix.
The only thing left of * VA is that when the cell is off, the light does not pass (although, to be honest, * VA has nothing to do with it).
The production of C-PVA differs from TN only in the orientation of the liquid crystal (see the previous proposal) and in the presence of 2 additional depolarizing films. There is nothing from * VA - no pixel splitting into domains with their clever orientation - everything is very simple.

Now I apologize for the offtop.
DO NOT BUY these gnusmasses, be patient: in theory, as soon as the old line of professional monitors is sold by other manufacturers, there will be more monitors on, more correctly, on CP-VA (analogue of LP-VA, etc.), and they will be tuned better than these gnusmas.

By the way, theoretically, if you put depolarizing films in a conventional TN matrix in the same way, then the main drawback - small viewing angles, will be eliminated, and the rest (mediocre contrast, but high speed) will remain the same. Who knows what else to expect from TN.

Samsung's SyncMaster F2380 LCD monitor is equipped with a new type of C-PVA matrix, which is hardly worse than the previous generation * VA, while the screen is 23 inches diagonal and the resolution is Full HD. Plus three inputs, a high declared contrast and an adjustable stand - together these parameters make it possible to consider the monitor as a candidate for the role of a universal display device, suitable both for work and for playing and watching a movie.

The design of the monitor is almost 100% utilitarian, almost as a couple of indulgences for the sake of decoration and to the detriment of ergonomics, everything is there. The monitor body and stand panels are made of matte black plastic. The surface of the screen is black and matte.The frame around the screen is very thin - 15 mm according to the manufacturer's data and protrudes from the surface of the screen by only 2.5 mm. On the bottom edge of the frame, exactly in the center, there is a "beard" made of plastic with a gray-silver coating, on which buttons are written in dark gray.

The protrusions on the buttons help you to find them by touch, and the markings on the front are visible, but it is still not convenient to use the buttons, especially in the dark. In addition, menu navigation involves moving up and down and left and right, and the buttons are simply arranged in a row. This is the first design flaw. The second one is the power indicator: between the “beard” and the screen frame there is a narrow insert made of transparent plastic, which is highlighted in white when the monitor is in operation. The backlight is dim, but not switched off, which is slightly distracting, for example, when watching movies. Even if the designations of the buttons were highlighted, but in the best case, in the light of this indicator, you can see the signatures for only two buttons. This is the second drawback, and that's it, then there are only pluses and admiration. The back of the monitor looks very neat.

The embossed pattern looks appropriate, the stand attachment point and ventilation grilles are covered with a removable flap. The connectors are located at the bottom end of the protruding part of the body and are oriented downward.

There is a mechanical power switch next to the power connector. Connecting cables is convenient, especially when you flip the screen to portrait orientation. A Kensington lock slot can be found in the corner on the back panel. The standard stand is screwed with two screws to two points of the VESA pad (100 mm square). If required, a second set of threaded holes can be used to attach to the bracket, forming a 200 x 100 mm rectangle. The telescopic stand of the stand is made of aluminum alloy with a black anodized surface. The supporting element of the base is a figuratively stamped thick sheet of steel. The stand and base are covered with plastic covers on top. The stand has several adjustments - height (130 mm range), tilt (1 ° forward and 20 ° backward) and left-right rotation - and allows you to flip the screen to portrait orientation.

The base of the stand has a relatively large footprint to keep the monitor stable even in portrait orientation with maximum elevation. The upper surface of the base is even and horizontal - you can put various small things on it, thereby utilizing the area occupied on the table.

The construction of the stand is quite rigid, there is no looseness in the joints. The monitor is supplied with a wire pin, by inserting it into the corresponding hole, you can fix the stands at the minimum height position, which is convenient, for example, when transporting the monitor.

The monitor has two DVI-D digital inputs (HDCP supported) and one analog VGA input. If the signal from the current input disappears, the monitor will automatically try to switch to another, but this behavior can be disabled in the setup menu.

For those who are forgetful or who like to watch a movie for the coming sleep, the automatic shutdown timer (1-23 hours in 1 hour increments) is useful.

Menu navigation is relatively easy and fast. The last page the user accessed is remembered, but not the setting on it. The bottom line of the menu displays a hint on the current functions of the buttons.

To improve the convenience of working with the menu, you can move it to the bottom edge of the screen so that the help icons are opposite the buttons themselves. When adjusting the image, the menu remains on the screen, which slightly interferes with the assessment of the changes being made. When there is no menu, the down button is responsible for a quick transition to the selection of profiles of brightness, color correction, color effect or aspect ratio (what exactly is indicated in the menu),

up button - call up the brightness setting, enter button - switch between signal sources. If necessary, you can select a translucent menu background and change the timeout. There is a Russian version of the OSD. The Cyrillic font of the menu is smooth and readable. The quality of the translation into Russian is good.We got the monitor without a manual and without a disk with drivers and software, but on the company's website you can find both Russian and English versions of the manual, as well as the driver and software. The program was of interest MagicTune, which allows controlling the monitor from a computer, but its current version refused to work on our computer.

There are settings Brightness, Contrast and Definition... List MagicBright - these are 5 non-editable profiles with combinations Brightness/Contrast, one custom, and when selecting a profile Auto contrast most settings are locked, and dynamic brightness control is enabled (the brightness is increased for bright scenes and decreased for dark scenes). Parameter Response time responsible for the matrix overclocking modes. (Rough and Exactly - manual substring for VGA signal).

List MagicColor - these are two preset profiles of color correction and a demo mode, in which the result of the image correction is displayed in one half of the screen, and the image without correction in the other. Customization Shade Is a list of three preset color temperature profiles and one custom one where you can adjust the gain of red, green, and blue colors. Function Color effect Allows a couple of clicks to switch the monitor to black and white, or convert the picture to shades of green, aquamarine and sepia. Parameter Gamma determines the current profile of gamma correction.

There are several modes of geometric transformation: you can either keep the original proportions of the image (Auto) by fitting it to the screen, or forcibly stretching it to full screen (Wide). When the mode is turned on AV and digital signals at the input, the picture can be forced to the format 4:3 with a small overscan (fit into the screen in height), stretch to full screen without (Fit to screen) or with a small overscan (16:9).

Dynamic color mixing (dithering) is not visible. Visually, the speed of the matrix is ​​low. At Response timea = Norm. a noticeable tail stretches behind objects in motion. At Response time = Faster and The fastest the tail is slightly shortened. When white objects move quickly against a dark background, the front of the objects takes on a greenish tint a few pixels deep. The viewing angles are very good, the diagonal effect is not pronounced.

Cinema modes were tested using a Sony BDP-S300 Blu-ray player. Subtle gradations of shades differ both in highlights and in shadows (a small blockage does not go beyond the "safe" boundaries). Apparently only RGB color is supported. Brightness and color definition are very high and are determined only by the resolution of the input signal. When scaling from low resolutions, artifacts do not appear, but jagged edges are slightly smoothed out. Regardless of the signal type, the geometric transformation is performed correctly according to the selected mode. Full HD at 24fps is not supported, as is 576i / 480i, but the monitor can handle 576p, 480p, 720p, 1080i, and 1080p signals. In the case of 1080i, the picture is displayed in margins. In 1080 modes, when the overscan is turned off, there is no interpolation, and therefore the picture clarity is maximum. The monitor did an excellent job of showing fragments of films and cartoons containing both dark and bright scenes. Due to the very high contrast ratio, black bars at the top and bottom are almost invisible in the case of 2.35: 1 film format.

We checked some of the matrix parameters using our devices. The technique is described in detail here. All tests, unless otherwise stated, were conducted with a DVI connection and with Shade = Norm., Brightness = 100 and Contrast = 79.

To assess the quality of color rendering, a GretagMacbeth Eye-One Display LT colorimeter was used. Target parameters: gamma = 2.2, white point = 6500 K.

A SAMSUNG SyncMaster 913N monitor with no signs of life was brought for repair. An autopsy showed that the power supply burned out, the TOP246NY PWM controller tore in half, knocked out a 2 A fuse, everything seemed to be standard. But that was not the case, the repair was delayed for several months.

The owner really wanted his monitor back so badly that there was no time to take a good picture of everything.Therefore, I will briefly tell you the history of the repair with a minimum of photos.

Since the malfunction is so obvious, the burned out PWM controller was removed, all the piping and secondary circuits of the power supply were checked, everything was normal. Instead of a fuse, a 60-watt incandescent lamp is connected to safely turn on the power supply. I had one PWM, I installed it, collected everything and tried to turn on the monitor. There was a hurry, they wanted to pick up the monitor as soon as possible. The protective lamp flashed briefly - the power supply started up, secondary voltages appeared and disappeared, and the lamp suddenly lit up with an even light, although the PWM did not fly apart, it went into a short one.

That's it, we’re in a hurry! I bought TOP246NY with a margin and calmly began to figure out what was the matter. After the next replacement of the microcircuit and checking, just in case, optocouplers, zener diodes, etc. etc., the power supply was started but without the main board.

He started normally, but the standby output voltage, which should be 5 V, floated from 4.3 to 4.8. Suspicion fell on the filtering capacitor 100 μF 450 V. It was thoroughly glued into the board and outwardly did not arouse any suspicion. But as soon as I touched the right leg with tweezers, it became clear that it burned out inside the case and instead of a constant voltage we got a pulsating one, which apparently knocked out the PWM controller after the first replacement.

The capacity was replaced, the voltages returned to normal, the protective lamp was removed, a 2 A fuse was installed. The power supply board returned to the chassis, but alas, the monitor does not work. The LED is on, we press the power button, it goes out and that's it, there is no backlight, the power supply does not start any further.

Since I have already examined the entire power supply board, it remains to check the motherboard and, upon a cursory examination, there was still a problem. The punched (with a hole) linear regulator APL5522, which from 5 V, formed 2 voltages of 3.3 V and 2.5 V. It was not possible to buy a replacement anywhere in the vicinity, an order was made for Ali immediately with a margin, as much as 10 pieces.

3 weeks have flown by, the package has arrived, the microcircuit is installed, 3.3 volts is normal, but instead of 2.5 only 1 V and the microcircuit case heats up a lot, what remains? The search continues. I didn't look for the circuit, but just by dialing I found out that this voltage goes to the capacitor C406 and the 87th leg (if I'm not mistaken) of the SE7889-LF scaler.

This leg showed 0.14 ohm to the ground, no more traces of this power appeared. I removed SE7889-LF, the short circuit went away, 2.5 V recovered, it remains only to wait for the next package from Ali.

Within 12 days, the package arrived, today I installed the microcircuit in place, to the joy of the owner, the monitor turned on and is now fully functional, and as a gift he received a package with faulty elements.

P.S. What can I say about the malfunction, apparently from the long and intensive use of the monitor, the leg of the filtering capacity of the power supply corroded and burned out, the PWM controller could not stand the ripple and also ordered to live a long time. Maybe the ripple in the secondary circuit of the power supply unit damaged the linear regulator APL5522, and it has already finished off the SE7889-LE, but it can also be a reverse sequence or just 2 malfunctions that are not related to each other.

All spare parts cost 650 rubles. waiting for almost 2 months.