Repair of TVs

TV today is probably in every house. What if he broke down? Firstly - do not panic, because very often with repair can be managed independently. Let's talk about the different models of TVs, their possible damage and about how much repair of TVs with their own hands is possible with any malfunctions.

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Cathode-ray tube model

Today, this type of TV is considered obsolete, but many are still actively using it, and its chips work just like more modern LCD TVs or plasma. Of course, the way the image is constructed is very different, but the elements themselves have many similar parts.

Accordingly - the repair of televisions will be made by the same methods, and therefore should start with these models.

Recommendations for repairing

Self-repair of any electrical equipment is a very dangerous occupation, so observe the safety precautions and the following recommendations:

1. If the technician refuses to switch on with a working socket, plug and cord from the TV, check the switch.
2. For convenience of repair work, you can dismantle the main board. But keep in mind that even disconnected from the network, it can be very shocking.
3. You also need to discharge the electrode of the kinescope. Find it easily - most often it is hidden under a rubber gasket. Work carefully, do not touch the metal parts. The gasket is easily clipped by a conventional screwdriver, and the electrode is pulled out by rocking.
4. The rod must be discharged to the housing or ground. Discharge the electrode is necessary until the characteristic cracking ceases to appear.
5. Modern TV models are equipped with a single board, on which repairs are carried out. Part of the damage can be seen with the naked eye. For example, inflated capacitors.
6. If the resistor is damaged, it will turn black. This does not mean that it burned out, but points to the chain where the damage is.
7. Frequent breakage is chipped or small cracks in the soldering of parts. Because of them contact may disappear. Therefore, even if it's not a soldering - look at all possible places, if necessary - go for details.

Consider the most frequent breakdowns.

Fuse

Any electronics is necessarily equipped with a fuse. It saves chips from voltage drops, and does not allow them to burn. Therefore, if the TV does not give any signals, it is necessary to start the repair with a fuse.

For this, the burned out part must be removed and a 100 watt bulb connected to its terminals, it has a large resistance and will not allow the circuit to burn more strongly.

Important! During normal operation, the lamp lights up, and after switching on the equipment it goes out. Of course, with such a modification the device can work with errors.

Diode bridge

This part is necessary for rectifying the current. If the power consumption increases sharply, one of the branches of the bridge will burn out. Often these are two diodes.

You can check their operation with a multimeter. And before that, you should turn to the electrical circuit and understand where the current goes.

Important! Do not forget that in any scheme, electricity is sent from plus to minus.

Posistor

This part works in the same circuit with the withdrawing voltage from the cathode ray tube inductive loop. If the work of the part is incorrect, the screen will show the rainbow. Accordingly, the motion of the electrons is violated, and the problem lies either in the burned posistor or in the loop.

To check the parts, disconnect the circuit from the electricity supply and connect the power. If the light bulb, which was lit earlier, ceased to burn, the problem lies in these details.

The technician can arrange a small test: without a loop, he can briefly turn on in the operating mode. To find out which part of the circuit is burnt out - measure the resistance with a multimeter. The resistance of the first two inputs on the posistor will be from 300 to 600 ohms, the second - from one to five ohms.

Important! If you replaced the fuse with a light bulb, it is forbidden to keep the TV set in working condition for a long time. The technique is faulty and is under high voltage. It takes just a few seconds to check it. Next, unplug the device from the wall outlet to avoid damaging the circuitry.

What else can fail?

At the input of the power supply unit you can find:

• capacitor;
• transistor.

These parts can easily be pierced by a multimeter for breakdowns.

Important! If the diode bridge burned, the fuse could not protect it, which means it is only a consequence of the cause, and the breakdown should be looked for deeper.

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LCD TVs

Repair of TVs of this type is in many respects similar to electron beam models. Of course, there are no posistors. But from this it is only easier to find out what is the breakdown.

There are two types of LCD TVs, the repair of which will vary:

• with discharge gas lamps;
• with LEDs.

Gas lamps

They are very different from those used in ceiling lighting. These are small thin white strips.

To accurately identify the problem:

1. To test them, remove the back cover of your TV and disconnect the wires from the matrix.
2. Next, take a working lamp and check how it behaves with the technique.
3. If the TV uses several lamps, you will have to remove the matrix, turn on the TV, find a non-working lamp and replace it.

LEDs

If you need to replace the crystal - think about how much it is profitable. Even in cheap models, the cost of a single crystal can reach more than half the cost of a TV.Therefore, it is necessary to repair the TV only in extreme cases with expensive models.

For plasma TVs it's still easier. The repair scheme does not differ from the rest of the models, but there are no posistors and backlighting, and accordingly - elements that require repair much less.

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More breakdowns

In addition to the listed, other breakages of your equipment are possible.

The horizontal strip of the

is lit. With this problem, the TV catches a signal and you hear a sound. But in the middle of the screen you can see only a white band. Most likely, that the personnel microcircuit has broken. For diagnostics, call the microcircuit, and in case of a breakdown, replace it with a new one.

No sound

If there is an image, but there is no sound, the TV speaker may have broken. What we do in this case:

• To diagnose the failure of the speaker, you need to ring its contacts - the resistance should be from 4 to 8 ohms.
• You also need to check how well the wires are routed to the speakers.
• At the same time, check the soldering of the board near the audio connector.

If you are not coping with the repair yourself, it is better to contact the service center where professionals will repair the TV.

The

is out of order. The device of the remote control is quite simple, and with its repair you will be able to cope on your own.

You will need:

• soldering iron;
• exchangeable keyboard;
• actually the console.

First, we'll deal with the keyboard. During operation, it may become unusable, so disassemble the remote, clean its contacts with alcohol and replace the keyboard. After that, the console must be assembled and checked.

It is also possible that the reason lies in the microcracks on the console board. Carefully inspect it and disappeared.

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Summing up

Repairing your TV yourself or at least diagnosing the problem is not an easy task. But if you do not have at least initial knowledge about the work of electronics or do not know how to solder, then it is better to entrust the matter to a specialist.

If the TV model is inexpensive - calculate the cost of repairs, it may be cheaper to buy new equipment. During the work, be sure to record all the steps you have taken - so it will be much easier for you to assemble a TV set. Be sure to follow the safety instructions for all work.