DIY TV repair: video

Without video and audio equipment, few people already represent a full-fledged home, and it is precisely because of the regular and intensive use that this type of equipment is most often damaged. Repair of TVs can be done at home, if you call the master, or do all the work yourself.

Diagnostics

Before starting repair work, you should determine what exactly broke on the TV. In any case, this will greatly facilitate both the independent repair process and the explanation of the essence of the problem to the telemaster.

The main types of malfunctions:

1. The device does not turn on. Both in kinescope models and in more modern LCD TVs, a malfunction occurs due to a blown fuse. But in different devices, it can be represented by various details. At the same time, the problem may be a burnt diode bridge;

   

2. Imported and domestic projection televisions very often lose their potential. The posistor is responsible for this function;
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3. Breakdown of plasma monitors. This may include color changes, swings, noise or dark (light) stripes on color TVs during broadcast;
4. But sometimes the problems of turning on or working certain functions will be a malfunction in the power cord or outlet.

Of all these troubles, the most difficult to fix is ​​a broken screen. For example, if bright reflections appeared on the monitor after hitting or getting water on the matrix, then it is better to immediately take the device to a service center, where it can be repaired under warranty.

LCD and LED Repair

But most repairs can be easily done with your own hands. Let us consider in order how to carry out urgent repairs of home LCD and LED TVs Thomson (Thomson), Sharp (Sharp), Samsung, Panasonic (Panasonic) and other models:

1. The difference between the above types of TVs is in different backlighting, but in principle their work schemes are very similar. On LCD televisions, the monitor is illuminated by fluorescent lights, and on LEDs by LEDs. Therefore, if the monitor does not turn on, you must immediately check whether power is supplied to the backlight;
2. Regardless of brand, the back panel is removed. It is screwed to the base with screws. After that, you need to remove the power supply wires from the matrix (first unplug the device from the outlet);

   

3. To check their performance, you need to connect the most ordinary lamp to the contacts. Most commonly used at 100 watts;
4. It should be noted that for modern Toshiba (Toshiba), Sony (Sony), Philips (Philips), several backlight sources can be connected to the circuit, so you will need to check each separately;

   

5. For testing, the matrix is ​​removed, a lamp is connected to the contacts, and the power wire is connected to the network. If it is working, the lamp will light up. If not, you will need to replace the cable or repair individual threads.

In addition, a certain portion of the backlight may burn out.

In different models of television equipment, lamp replacement is performed in different ways. For example, for many Daewoo, Akai, and Hitachi TVs, to dismantle a burned-out lamp, it will be necessary to remove the matrix from the panel and reinstall the element on it. At the same time, for some Rolsen (Rolsen) and Funai it will be possible to change a burning lamp or a diode without dismantling it. Depending on the design, it will be necessary to bend (unsolder) the contacts, remove the gasket and carefully remove the burned element from the housing. In its place, a completely similar lamp is installed, both in parameters and in size.

Many Chinese models of television equipment - CTV, HLW, BBK, when disassembling, you can see the light stripes on the matrix. They indicate a breakdown of this particular element. Due to some external factors, the part stopped working and oxidized. In this case, you need to select an element that is identical in performance and install it in place of the faulty one.

Unlike the old stationary kinescope or portable models, plasma and ED versions are very rarely subject to repair if the screen breaks. This is a very time-consuming process, so not even all professional workshops undertake such work. In most cases, if the monitor is cracked, then it will be cheaper and easier to buy a new TV set than to repair an old one.

Video: PHILIPS TV Repair

Repair of picture tubes

Despite the total use of plasma, many owners still have more outdated picture tubes (say, Vityaz, Elt, Rubin, Horizon, JVC). Step-by-step instructions on how repairs are performed on electron-beam models:

1. If such a device does not turn on, you must immediately check the fuse. Check it out very easily. Unscrew the back panel, a board will be installed under it. The power terminals are connected to the fuse. They need to be switched to the base of a simple incandescent lamp and turn on the TV in the network. If the device is serviceable, then immediately after turning on the lamp will go out, but if the fuse is blown, then it will either light all the time, or vice versa, it will not give signs of operation at all;
2. Sometimes, as we said above, the reason lies in the breakdown of the diode bridge. Its adjustment and repair is made only after dialing. To do this, use a multimeter and a TV passport, which indicates the main parameters of the equipment. Remember that in the old TVs the “triangle” scheme was used, in which the electric current moves from the positive pole to the negative;

   

3. The most difficult problem of cinematic TVs is the breakdown of the posistor. To check its serviceability, you must first turn off and turn on the power circuit, while observing the working llama. If it goes out, then the part is defective. For repair, the network resistance is first set up, and then the posistor is replaced.

   

There may be different tips on how to check the posistor of a TV, but any professional telemaster will recommend that you measure the resistance between its contacts. The part has four, i.e., two pairs. The resistance of one honey can reach 600 Ohms, while the other can be in the range of 1–5 Ohms. But this is only a theoretical check, for a more accurate diagnosis it is necessary to solder the posistor.

In addition, CRTs often burn capacitors and transistors. They can be diagnosed even visually. They swell or change color on the board. If you see that the capacitor is blackened or cracked, then it needs to be replaced with a working analog.

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