In detail: do-it-yourself erisson 29f2 TV repair from a real master for the site my.housecope.com.
Erisson TVs have “bugs”. Previously, “bugs” were called errors and breakdowns in telegraph and telephone systems, as well as in radar electronics. Later, this professional slang word migrated into the vocabulary of programmers. So in modern widespread electronics there is also “bugs”- errors in design and construction.
One very common malfunction in CRT TVs can be called a "bug" Erisson... This malfunction manifests itself after a year or two from the moment the device began to be used and the cause of further malfunction is the transistor in the frame scan circuits. Frame scanning in CRT televisions serves to form a vertical image and controls the electron beam in the CRT.
As a rule, a "bug" manifests itself as follows:
The TV does not switch from standby to working.
Such a manifestation of the defect is due to the fact that in the event of a malfunction of the frame scan units in the TV, the protection against the kinescope burn-through is activated.
CRT burn-through Is when the screen has a bright horizontal bar in the middle of the screen. In this case, all the energy of the electron beam is focused on this narrow band, and as a result of this, the phosphor of the kinescope can be burned out in the place where the electron beam hits.
If you leave a TV with such a defect on for a long time, then later in the place where there was a horizontal strip there will be a section with a lower luminous efficacy (burnt-out phosphor) - the picture tube will be damaged. To avoid this, modern TVs have built-in protection against kinescope burn-through and the TV simply does not switch from standby (sleep) mode to working mode.
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Video (click to play). |
On the CRT screen, there is a bright horizontal line in the middle of the screen.
In this case, the protection against burn-through of the kinescope does not work, since the electric circuits of the frame scan are working, but the faulty elements still partially fulfill their function and the protection system does not “see” that a malfunction has occurred. Therefore, a bright horizontal stripe appears on the screen.
If there is a horizontal bar on the screen, then try to turn off the faulty TV as soon as possible in order to prevent damage to the kinescope.
It was with such a malfunction that the TV got on the repair table. Erisson (model 1401, manufacturer Telebalt LLC, Kaliningrad). The TV did not switch from standby to working... The cause of the malfunction was a transistor. 2SB764 with broken transition E–TO... The resistance between the emitter and collector leads was zero. This is what caused the protection against burn-through of the kinescope to operate.
On the circuit board, the 2SB764 transistor is designated under the serial number Q406... The transistor itself is located next to the microcircuit LA78040N... The LA78040N microcircuit is the main amplifying element in the frame scan circuits. A deflection coil is connected vertically to this microcircuit.
After replacing the 2SB764 transistor with a new one, the TV began to turn on, but a bright strip formed on the screen in the middle of the TV picture, and the image at the top of the screen was nonlinearly elongated. Teleradiomechanics call such a defect “bloat”. When turning vertically, the image is as if superimposed - wraps up... The photo shows a twist formed after replacing the 2SB764 transistor.
In addition to the resulting vertical twist, the new 2SB764 transistor got very hot during TV operation - there was still some faulty part in the circuit, leading to overheating of the replaced transistor. When turned on, the TV did not turn on for a long time, and the image first appeared in a narrow strip in the middle and then slowly expanded to full screen.
After a short search, it turned out that in a switching power supply, an electrolytic capacitor (47 microfarads. 50 V.) has a small capacity, which amounted to 19 microfarad. instead of the required 47. The capacitor has a reference designation on the circuit board under the number C933.
If you encounter a similar malfunction, be sure to check this capacitor.
After replacing the capacitor in the power supply, the image began to appear faster, but despite this, the image, when turned on, unfolded as if from a pillow. Transistor 2SB764 still very hot... After a couple of switching on the TV, the transistor struck again, despite the fact that a small radiator was installed on the transistor. So several unsuccessful attempts were made to replace the 2SB764, which resulted in 2 damaged 2SB764 transistors. The latter went out of order without even working for a minute ...
If you wander on the Internet on the electronics repair forums, you can find recommendations for replacing the 2SB764 transistor with a more powerful transistor 2SB772 in brand TVs Erisson, in order to exclude the breakdown of the 2SB764 transistor and the repeated failure of the TV - relapse.
In practice, it is not always possible to find a 2SB772 transistor. In this case, you can use a domestic transistor KT814... It, like 2SB764, 2SB772 has the structure P-N-P and the parameters are close to 2SB772.
After installing the domestic KT814 instead of the imported 2SB764, the TV began to work properly - the “twist” disappeared, and the excessive heating of the transistor stopped.
When repairing a TV Erisson 1401 with the described malfunction, first of all, check the 2SB764 transistor (Q406), if possible, replace it with more powerful analogs 2SB772, KT814. Also, an analogue of the 2SB764 transistor is 2SB985which can also be used as a replacement. You should check the capacitor in the switching power supply unit number C933. As mentioned, it may have a capacity loss.
A similar malfunction was observed in Erisson 2102... The already known transistor 2SB764 turned out to be faulty.
Darkening was observed on the circuit board around the 2SB764 transistor - evidence of excessive heating of the transistor. Due to overheating, the 2SB764 fails. Burnout of this transistor in TVs Erisson Is an explicit “bug”. The Erisson 2102 was restored by replacing the faulty 2SB764 with an analogue 2SB985.
The pinout of the terminals of the transistors 2SB772, 2SB764, 2SB985, KT814 is shown in the figures.
Erisson 2120 chassis 3S10
Cannot tune to channels. When automatically tuning to a station, there is no synchronization both by lines and by frames, the picture is b / w (it does not remember the channels and simply skips them).
On examination, it turned out that the L301 throttle was not drilled and the R325 burnt parallel to it. At first I thought that there was a memory failure, but when I entered the service (MENU-> AV-> ANAL), I did not find any deviations.
After checking the piping of the TDKS and the STV2248C video processor, I came to the conclusion that the latter was malfunctioning. After replacing the STV2248C, the device started working. PS: put a percentage on the socket because of the large number of defects on sale (luck smiled at me the second time). Whoever has “lit” 100 µF in position C009A - change to 10 µF to prevent memory failures in the future.
Erisson 1401 chassis MDY5
The power supply unit is going to the pediment. Power + V = 180 volts at a rate of 110 volts. Leaking transistor Q904 2SC1815. After replacing it and replacing R915 1.5Ω, standing along the + B circuit, everything returned to normal.
Erisson 1401 chassis MDY6
When you turn on the TV, the LED lights up, the screen is dark, there is no sound. The power supply unit at the + B output is twice as high. electrolytes С917, 922, 924, 403 are inflated. defective Q406 2SB764. I connect a 220V 60W lamp to + 110v. When the power supply unit is turned on, it goes into spacing, after a while the voltage stabilizes. In the power supply unit, I replaced the Q904 2SC1815, turned on the power supply network, it works great. Replaced IC801 LA42351 sound is. Thanks to the people who share their information on the site.
Erisson 1430
When working, the brightness floats, when very bright scenes appear, it goes to the duty room. If you lower the gain or lower the brightness, it works fine. checking the OTL circuit did not give any results.The reason turned out to be much simpler - a break in the filter capacitor at +112 V. After replacing the TV, it worked fine.
Erisson 1401 composition LC863532 LA76818 LA78040N
Defect - with an ideal picture, the jitter of service information (menu, channel numbers, etc., etc.) Replacing the C432 (in the personnel voltage boost) solved the issue.
Erisson CTV-3410 - does not turn on
Composition of NN5198K, AN5539, AN5274, HOT-2SD2500, BP-C4429
Failure of the cyclic bp as a result, the NOT was broken due to the increased voltage, replaced 2 - litas 47/25, 2200/35 also burned out PR901 according to the scheme is designated as 2-opposite on the diode written 300V from it 2-pins and a disk are left. on position C950, R950, ZD988 but no denominations.
R439 turned out to be faulty, its value became 2.1 Ohm, although it was 1 Ohm
put 0.56 Ohm bodies stopped off. C848 was swollen, the AN5274 sound was also out of order. Solved.
Sent by Sergey 100
Erisson S14 chassis 3Y11
LC863328C-55W0, LA76810A
It turns on, a green screen with the inscription ERISSON, gradually (within 5 seconds) the brightness increases, the screen fills with green without LOH. If you reduce the Screen - the screen darkens, the inscription is green. There is no sound, it reacts to switching channels. At the output of the VP - R - 2.2V G - 4.3B B - 2.5V.
To eliminate it, it is necessary to replace the LA76810A.
Erisson 1406 chassis 3Y11
STRG-6653
when the power supply is applied, the power supply starts for 2 seconds and goes to stop. Everything was sorted out in accordance with the recommendations for both the primary and the secondary, but the jamb was found R 612 the optocoupler power control circuit increased the rating from100 to 158kom
Erisson 21F1 chassis 3P51
TDA9381PS / N3 / 3, PSU - CQ0765RT
Came with a failure to start the power supply unit. I found a C615 1500/2 KV capacitor that was darkened with a crack, but it still didn’t start up, I replaced the micr. in the power supply unit CQ0765RT, the TV started, everything worked fine, but after turning off the power button, the power supply unit did not start again, I checked the litas. After a long idle time, the TV turned on, but after turning off the power button, again there is no power supply start. When it did not start, there was no voltage on the microcircuit to start 18v, I replaced the D614 zener diode with 18v and everything went, although before that the zener diode was checked as a whole, and after replacement checked, also normal, whorled it can be seen under voltage and planted 18v
Erisson 2120 chassis 3S10.
On HF it works fine. On AV - there is no signal. If you turn off the “blue background” function, the signal from AV goes, but there is no synchronization.
Replacing the video processor STV2248C solved the problem.
As it turned out later, the client connected TRICOLOR to hot.
Erisson 2109 chassis 3Y11
B.P. - STRG-6653
The power supply starts for a moment with overestimated output voltages (instead of 110v -140m, instead of 20v-25v, 5v is normal), and immediately goes into protection (at the outputs = 0 v) - The problem was solved by replacing the interrupted resistor R642 = 100 ohm in the optocoupler circuit ...
Erisson 21UF20 chassis 3P61E
I flashed TDKC BSC29-3807B and dragged off the TDA4865AF frame chip. There was no native TDKS. The client was literally breathing down the back of his head, so he had to improvise from what happened. The BSC25-N0809A from AVEST 54ТЦ-04 was successfully installed with a minor modification, which consisted in a home winding on the core of an additional winding of 10 turns connected to the 7 and 9 TDKS terminals. Instead of TDA4865AF, the TDA4863AJ quietly came up.
Then I read on the Internet that the BSC29-3807B has a direct analogue - 6174V-6006M (n). This means that a reverse replacement at AVESTA is possible without alteration.
Erisson 2103 chassis BN37
When the TV is turned on, the brightness starts to increase and the power supply protection is activated. The problem was solved by replacing the Q504 2SA1015 transistor, which was broken through to-e and completely opened the cathodes.
Erisson 25F2 chassis BN88
When turned on, the relay cyclically clicks on B +, power stabilization is violated. Banally increased (up to 40 ohms) its resistance R902 = 1.5 ohm 5w, in the emitter Q904 (2SC4429) B.P.
Erisson 2103 chassis E3701-022010A2
I came with a complaint: it stupidly reacts to the remote control, no more than 1.5 m. I noticed the photodetector and the LED next to it less than 1 cm. I put a black partition between them. From 5m it responds perfectly.
Erisson 21SF10 chassis 3Y18
The vertical size spontaneously increased, the adjustment in the service did not help for long, the signal disappeared until you restart the TV.
I installed a new memory with a working firmware, no failures.
Erisson 1401 chassis MDY5
BP - clearly gave out overestimated voltages. On the circuit: + 26V was + 41V. Faulty: pos: IC401 - LA78040N; pos: Q406 - 2SB764; Replaced litas: pos: C922 - 1000 / 35V; pos: C420 - 330 / 35V;
The culprit of the malfunction turned out to be: RP901 1k - installed in the stabilization circuit (burnout). Replaced and litas: pos: С934-С933 47 / 50V
ERISSON 21SF40
Composition: 8896CSNG7E18, LA78041, 24C16A.
Fault: the image is shifted to the right by 3 centimeters, on the left there is a “torn” edge. The culprit - R466 10k in the cliff, stands from the 7th leg of the TDKS ABL, then through R227, VD210 at 27 pins.
Erisson1401 chassis E3701-054070A
Does not leave standby mode. (From the words of the owner: when turned on, the picture either immediately appeared normal or was compressed horizontally, after some work it could be restored.) Upon examination, an incorrect Q406 was revealed (the key for powering the IC401 (LA78040) KR, and the pre-output stage of the horizontal scan), as well as changed in BP e-you C933, C934. After that, the TV turned ON-OFF-ON-OFF, the screen did not have time to light up. The KR became very hot and again the breakdown of Q406 (all the voltage from the power supply unit is normal). When replacing the KR (LA78040) and C432- (voltage boost), everything remains the same. After a long study, the turn-to-turn personnel winding turned out to be faulty, during external examination it was not revealed, and the tester R = 3.4 Ohm. Compared to a similar operating system on which this chassis is working properly, R = 16 ohms.
Erisson 2106 chassis 3Y11
After a thunderstorm. Changed memory, did not save data.
Unpleasant jammed sound. Illegible speech, especially on Russia-1.
The ULF works purely without distortion; the sound standards are really switchable.
Defective video percent. LA 76810A.
I did without replacement. I used UPCHZ-2. I spoke beautifully.
Erisson 2120 chassis 3Y11
hiss instead of sound on the 6.5M standard, the effect is as if the sound standard is not turned on correctly. The reason turned out to be a video processor: LA76810A
Erisson 29F2 chassis BN88
https://my.housecope.com/wp-content/uploads/ext/2254/section1/topic118029.html
It turns on, the line starts and immediately off - the relay opens.
Blame Q405 - A1320.
Erisson 21UF20 chassis 3P66
I could not start at full strength, there is a horizontal bar on the screen when adding a screen for a few seconds and restarting. Instead of 5V on 3.45V processor. The culprit is S8050, 5V processor power supply. Phoned as serviceable.
ERISSON 29F5 BN88
Clicks inside (according to the client), breakout of bsc25-0101c output. It is far to the store (160 km), and there are plenty of samsungs with a “sweet couple” in the firewood. TDKS was installed with SCT-11 FCV-20A001 with a slight re-routing and the values of R426-2.2om / R427-4.7om were changed, and the heat was corrected (1st). This year, such devices hit 2 times, in the first case, another percent was killed. I forgot to solder the ABL wire in the re-routing photo. (Ed. By gilan)
LG863324A processor,
memory ST24C04.
tuner EWT-5V3S32-E08W
When turned on, the network button or remote control can immediately turn on and work without any remarks. But it may not turn on for a long time. If you turn off the network and turn it on again, then everything repeats. It can turn on, maybe not.
During the manifestation of a malfunction, the indicator dims by half, although usually the transition from worker and vice versa from duty to worker in this model, the indicator does not react.
In memory and in the process, the 5-volt voltage drops to 2.72V.
Sometimes in this state, you can turn it on from the control panel, the sound and sound of the last state appears, but there is no reaction to the remote control.
Memory microchip malfunction. Replacement, firmware solved the problem.
Received TV on repair Erisson 29SF10, chassis 5Y19E. Such a healthy and heavy suitcase. I was not at work at that moment, so I don't even know how the guy covered the TV in the workshop.
He called me and said that the TV was not showing. Well, it doesn't show, so I'll do it. The TV did not turn on. I immediately disassembled it and visually did not find anything. Although I found a burnt Drosselek. I rang it, it turned out to be burned out.
Soldered instead of him another. I turn on the TV, and it stinks and smells burnt. It turned out that the throttle had burned out again.
The line transistor 2SC5841 burned out, although the circuit should be 2SC5299. Here she is carelessness. I would put a 100 watt lamp instead of a load and everything would be whole.
And the line transistor burned out because in the personnel strap there was a hooked capacitor C451 - 35V 100mf. He pulled the throttle and, of course, the personnel chip N451 - LA78041. After replacing the line transistor 2SC5841, a horizontal stripe appeared on the screen of the Erisson 29SF10 TV. Here, then the personnel is also covered.
I changed the whole thing for new details. I connected incandescent lamps instead of a line load and a power supply.
Included, lowercase and personnel plow. I removed the lamp from the line load and left the lamp in the power supply, which I put instead of the fuse. I switched on the Erisson 29SF10 TV again, the pulses are on, it means the TV is working.He took off the load lamp and the TV shows like new.
Everything, repair Erisson 29SF10 finished…
Copyright Gertc.
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Posted on Tuesday, October 21st, 2014 at 12:50 am Posted in Category Work Offline. Subscribe to comments RSS 2.0, You can skip to the end and leave a response. Pinging is currently not allowed.
Interesting. We can say lucky - everything is in reality. And I fucked with a similar device like "Samsun" for two days - the protection knocks off and that's it. You turn off the power of the lowercase - the power supply is working. Well, I think TDKS, there is nothing more. They searched for a long time but did not find it. And so he stood. I brought the owner to the merchants (we have lovers of just such a technique). Their specialist climbed in and it turned out that in one small inductance there is an inter-turn one. Experience helped, so to speak. This coil is located on the board on top of the deflector. Such is the bullshit.
Yeah, I've also seen such coils. The joke is that the client said “the TV doesn’t show”, but that there was a strip in the middle of the screen, he kept silent or forgot to say. So I would immediately replace the personnel and burned out harness and that's it
It is impossible to imagine a modern apartment or house without video and audio equipment. This equipment is used every day and therefore breaks down more often than others. There are several ways to repair TVs: send the technician to a service center, call a qualified technician at home, or make repairs with your own hands.
Before you start repairing a TV, you first need to make sure what the problem is. This will also help if you do the repair yourself, and then when the master comes, you will be able to explain the situation to him.
There are several types of malfunctions that can most often be found when a TV breaks down.
- The technique does not turn off. In independence, a CRT TV or a modern LCD model has broken down, this malfunction is associated with a blown fuse. Only different models have distinctive details from each other. You should also pay attention to the diode bridge - perhaps it was he who burned out.
- In both domestic and imported models, the potential can often go astray, for the function of which the posistor is responsible.
- If the plasma TV monitor is broken, then the problem, most often, is interference or drops, light or dark stripes may appear, color changes while watching a program or movie.
- The problem may be a broken cord or a faulty outlet.
If we take into account all the troubles listed above, it is worth saying that the most difficult breakdown is considered to be a screen malfunction. For example, light reflections appear on your monitor after the liquid hits the matrix or the TV is hit, then it is better to carry it to the teleservice. Here it will certainly be repaired, and if the warranty period has not expired, then it will be free of charge or at a reduced price.
See also - How to choose a TV for your home in 2018?
You can try to fix some malfunctions of TVs yourself. And it doesn't matter here - these are LCD models, LCD or LED, it is not necessary to call the wizard if you are confident in your abilities. But caution never hurts, because such TV models are not cheap, and without having any repair experience or knowledge in this area, you can only harm and aggravate the breakdown.
Before you start repairing LED or LCD TVs, you must carefully read the instructions, and also study the principle of operation of your model. Anyone, even one far from this field, will understand that the repair of TVs such as LCD or LED will differ from CRT models. In the latter case, you are guaranteed not to run into a faulty PTC thermistor. The main thing here is to determine the problem, why does the backlight not work?
If you are repairing LCD, LED models, then the only difference here will be what kind of backlight is used. If it is an LCD TV, then the backlighting is produced using fluorescent or fluorescent lamps. For TVs, LED backlighting is produced using LEDs.At this point, the differences between LCD models usually end.
The breakdown can only consist in the fact that there is no power, in order to check this on an LCD TV, you can do the following with your own hands:
- open the back cover of the model;
- remove the wires connected to the matrix;
- connect the working lamp to the contacts;
- there are also LCD models in which more than one light source is provided. In this case, all sources must be tested. Just dismantle the matrix and plug your TV into the network - you can see which LED is the problem.
When a broken lamp in an LED or LCD TV is identified, it must be replaced. This stage requires maximum care from the master, as well as the manifestation of special attention. In some cases, the lamp is removed without removing the matrix, you just need to move the protective elements with a rubber gasket and pull out the lamp with a soldering iron. Similarly, it is necessary to mount a working light bulb. Now we can congratulate you - you did the repair of the LCD TV with your own hands! Just pay attention to one important nuance - the new light bulb must fully meet the parameters and dimensions of the broken one!
To repair TVs yourself, look carefully at the matrix! If there are "unhealthy" streaks here, then the breakage is in the matrix. Have a new part? Then everything is simple! You change it and turn on the TV, if it works, then you have accurately identified the breakdown.
If the reason for the breakdown of LCD TVs is the screen, then it is best to purchase new models of LCD or LED equipment. It is not recommended to change the screen of LCD and LED models, as it is impractical! This also applies to the LCD matrix.
What could be the problem with a malfunctioning plasma TV? If it is necessary to repair plasma TVs, then proceed in the same way as described above. Just adapt it to your specific case. This description can be applied to any model of plasma TV, just stock up on the necessary tools in advance.
Although today most users prefer to use plasma, many still watch programs on more outdated CRT models. Let's find out how to repair a breakdown in such TVs. Below is a step-by-step instruction that will help you repair your electron beam product with your own hands.
- If you do not turn on such a device, check first of all the fuses. In these TVs, the back is made up of panels. Therefore, it is necessary to unscrew that part of the panels. Under such panels you will find a board and the power terminals must be connected to the fuse. They are connected to a conventional incandescent lamp, or rather to its base, after which the TV must be connected to the network. In the event that your equipment is in good working order, the lamp will go out after switching on, otherwise, when the fuse has blown, it will either not work at all, or it will constantly burn.
- The diode bridge may also break. It should only be borne in mind that it is necessary to regulate and repair it only after making a dial. In this case, not only a multimeter is used, but also a product passport, which indicates the main parameters of this model.
- The most difficult breakdown in a TV with a kinescope is a posistor. To check with your own hands, you must first turn off the power circuit, and then turn it on. In this case, the lamp must be monitored. If the work lamp goes out, then it can be said that the posistor is faulty. To make repairs, it is necessary to adjust the resistance of the network and only ventures to change this part.
But not only the matter may be in the posistor, transistors and capacitors burn out in CRT models. The diagnosis of this breakdown can also be made visually. If the condensate is blackened or cracked, then we replace it with a serviceable analogue. Now you know why the TV does not work and how to fix it yourself.
Good time, I need help on this TV, can anyone come across or repair it, after turning on the protection is triggered, percent. I read the S3C8849X48 controls on the forums, you need to throw 41 legs off, that is, off. All protections, I turn on the TV set, everything is OK, it has been working for 2 days, but I don't want to leave it so much.
KVASS: but I don’t want to leave - Well, tell me, what is stopping you now to SEPARATE the protections that go to this conclusion and figure out which of them you are triggering, or is the protection itself simply “falsely triggered” due to problems of the “sensor” or the key ?! 
Or are we waiting for the finished one?
Yes, I figured it out, the heat protection works, but there is a dead end, I checked the piping, everything is ok, but it doesn’t work, I’m already thinking the pipe can, but although it shows well
KVASS: I checked everything, everything is ok, but it does not work - the approach is simple!
1. WHAT I checked and the VALIDITY of checking - nothing normal - REPLACEMENT!
2. Amplitude of the IOC on the glow or the voltage of the glow? There may be problems in the UPS (B +), etc. ...
Hurray found. Two electrolytes, one in the personnel power supply 100x16v, the other 10x160v in the line power supply, the most interesting thing is that the omics call perfectly for the discharge of the charge, but with the ESR device already assembled for a long time, from the same forum, the author of mine GO, I throw it at him, I didn’t believe it , the readings are zero, although I constantly check the air conditioners for them, and I measure the shunts, this is how it happens with electrolytes, like a whole one, but does not work, in short, I replaced them and immediately the TV set started working!
KVASS: one in personnel power supply 100x16v, the other 10x160v in line power supply +
KRAB: There may be problems in the UPS (B +), etc. =
Yes, it seems to work. In general, the Errisons Polars, this is such crap, they set up the defenses, and they hover their brains specifically, it would seem in the intense protection of the problem, but in fact there are problems with the feed.
KVASS: seemingly in an incandescent protection of samples - the way it is - B + underestimated - and the heat - underestimated (and vice versa) 
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It is no secret that a breakdown of a television receiver can ruin the mood of any owner. The question arises, where to look for a good master, do you need to take the device to a service center? You need to spend your time on this, and what is important - money. But, before calling the master, if you have basic knowledge of electrical engineering and know how to hold a screwdriver and a soldering iron in your hands, then repairing the TV with your own hands in some cases is still possible.
Modern LCD TVs have become more compact and easier to repair. Of course, there are breakdowns that are difficult to detect without special diagnostic equipment. But most often there are malfunctions that can be detected even visually, for example, swollen capacitors... With such a breakdown, it is enough to evaporate them and replace them with new ones with the same parameters.
All TV sets are the same in their structure and consist of a power supply unit (PSU), a motherboard and an LCD backlight module (lamps are used) or LED (LEDs are used). It is not worth repairing the motherboard on your own, but the power supply unit and screen backlight lamps are quite possible.
As already mentioned, the design and principle of operation of LED and LCD TVs, regardless of the manufacturer, are the same. Of course, there are some differences, but they do not play a significant role in the diagnosis of faults. Often, in the event of a problem with the power supply, the LCD TV does not turn on at all, while there is no indication, or it turns on for a while and turns off spontaneously. Using an example, the repair of a DAEWOO LCD power supply unit (can be applied to plasma) is considered, which is not much different from repairing an LG TV, as well as Toshiba, Sonya, Rubin, Horizon and similar models.
- First of all, before you repair the TV, you need to remove the back panel of the device with a screwdriver by unscrewing the screws. On some models, the rear wall may be latches installedwhich must be handled with care so as not to break them.
- After removing the cover, you will see the power supply unit, consisting of several modules on the left, and the motherboard on the right.
- On the power supply board you can see 3 transformers: the bottom one is the mains rectifier choke, the top one on the left (large) feeds the inverter, and on the right is the standby power supply transformer. You need to start checking with it, since it turns on the standby mode of the TV receiver.
- Duty transformer when the device is connected to the network, it should give out a voltage of 5 V. In order to correctly find the wire on which you need to measure the voltage, you can use the diagram, or you can see the markings on the case. In this case, opposite the required contact is written - 5 V.
Measurement is taken first open circuitby connecting one probe to the found contact, and the other to the cathode of the diode on the radiator. In this case, there is no break. 
As you can see from the review presented above, repairing TV power supplies with your own hands is not such an overwhelming task. Following this description, you can also repair plasma TVs.
Do-it-yourself TV repair with a kinescope, for example, such as: Rubin, Horizon, Sharp 2002sc, LG TVs, as well as repair of the Vityaz TV, begins with checking the power supply unit for operability (this is done if the unit does not turn on). It is checked using incandescent bulbs for 220 V and a power of 60-100 W. But before that, be sure to disconnect the load, namely the horizontal output stage (SR) - connect a lamp instead. The CP voltage ranges from 110 to 150 V, depending on the size of the tube. Must be found in the secondary circuit SR filter capacitor (its values can be from 47 to 220 microfarads and 160 - 200 V), which stands behind the SR power rectifier.
To simulate the load, you need to connect a lamp in parallel to it. To remove the load, for example, in the popular Sharp 2002sc model, it is necessary to find and unsolder the inductor (located after the capacitor), the fuse and the limiting resistance through which the CP stage receives power.
Now you need to connect the power supply to the power supply unit, and measure the voltage under load.The voltage should be between 110 and 130 V if the CRT has a diagonal of 21 to 25 inches (as in the 2002sc model). With a diagonal of 25-29 inches - 130-150 V, respectively. If the values are too high, then it will be necessary to check the feedback circuit and the power supply circuit (primary).
It should be noted that electrolytes dry out during prolonged operation and lose capacity, which, in turn, affects the stability of the module and contributes to an increase in voltage.
When the voltage is too low it is necessary to test the secondary circuits to exclude leaks and short circuits. After that, the diodes for the protection of the power supply of the SR and the diodes for the power supply of the vertical scan are checked. If you are convinced that the power supply unit is working properly, then you need to disconnect the lamp and solder all the parts back. This check can also come in handy when doing DIY Philips TV repairs.
Another common breakdown of the TV that can be eliminated is the burnout of the backlight lamp. In this case, the TV receiver, after switching on, flashes the indicator several times and does not turn on... This means that after self-diagnosis, the device notices a malfunction, after which the protection is triggered. That is why there is no image on the screen.
For example, a Sharp LSD TV receiver with this malfunction was taken, although in this way it is possible to repair Samsung TVs, Sony Trinitron, Rubin, Horizon, etc.
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To fix the TV, you need to remove the back cover from the TV. This requires a screwdriver or screwdriver.
Next, you need to be careful disconnect loops from the matrix. 
Thus, you can repair the Philips and LG TV with your own hands, and other LCD panels, as well as devices with LED backlight (LED). Owners of the latter type of devices should read the article on repairing LED backlighting, where the whole process is described in detail using the example of an LG TV.
Among the typical and simple reasons that the TV set does not turn on, there may be a remote control or a lack of signal from the antenna cable.
If the TV does not turn on with the remote control, first, you need to make sure the batteries are good. If they are shrunken, replace them. Often the TV set cannot turn on due to contamination of contacts under the buttons. To do this, you can disassemble it yourself, and clean the contacts with a soft cloth from accumulated dirt. If your remote control has been dropped, it is possible damage to the quartz emitter... In this case, it must be replaced. Well, if you filled the remote control with water or some other liquid, and it did not work after disassembling and drying, then it will have to be replaced with a new one.
You can learn more about fixing the remote control in the following video or article.
When repairing TVs LG, Sharp with LCD, Rubin, Horizon with the same screens, a situation often arises when it does not turn on when the device is in good working order. It turns out that the reason may be no TV signal in the antenna cable. This happens due to the operation of the noise suppression protection (in Rubin TVs, they began to install it not so long ago), and the unit goes into standby mode. Therefore, if you find your TV set inoperative, you should not panic, but you need to check the presence of a signal from the transmitting station.
In conclusion, we can say that when you decide to repair a TV set yourself, you should soberly assess your abilities and knowledge in this matter. If you do not feel confident, then it is better to entrust this matter to a telemaster, especially since nobody canceled 220 V, and ignorance of basic safety rules can entail unpleasant consequences.
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