It's a pity to throw out the TV worth 50,000 rubles and more, on the contrary, cheap LCD panel is sometimes easier to buy than to replace the matrix. Meaning it takes in private companies, staffing comprises a cell master. Surprising keen interest to ensure that the conduct repair of television with his own hands, breakage can be negligible, the gain is obvious. How not to be killed shock, do not break the device? Plan to discuss today's review, we list the main types of faults.
Repair of TVs with cathode-ray tube
The percentage of models with cathode-ray tube is great. It is logical to begin to consider with them how to repair the TV, because switching power supplies are considered to be part of any equipment. Liquid crystals, OLED (organic LEDs), plasma. Scan chip exploit similar principles. the imaging method is different, but the element base is similar. Therefore, the repair of television with his hands moving trodden footpaths.
The equipment comprises fuses. Open secret event of force majeure (lightning, power surge, falling equipment) - should break the protection. Almost the end of the catches of the chip. From start to fuse. Of course, if the apparatus is devoid of signs of life. In normal operation, the current through the fuse zero, experts have come up with to use the repair fact put at the service. Burned part removed, is attached to the terminals 100-watt light bulb. The resistance is relatively large, will be a good current limiter circuitry paused burn on.
Note. According to Ohm's law, power allocated to the circuit section, proportional to the current. Limiting value will avoid burnout electronic components. Actually, so do complement circuit current limiting resistor. Lamp will display purposes makes it clear passes an electric current. Spiral heating up, see the light.
In normal mode, light will blink and then goes out after switching on the TV. Wherein the apparatus works with the additive slightly incorrectly. There are two details that often burn in a cathode-ray tube:
- Diode bridge rectifies the current. With a sharp increase in the consumption of one branch of burns. Usually two diodes fail. Determine the fit can be continuity. Diode current passes one direction, the other valves are closed. The circuit triangle indicates where the current flows. On representations of the circuitry current always flows from plus to minus. Accordingly, place the electrodes from a dial.
- The second part is called posistor curious working on an inductive loop tasked with removal capacity with the cathode ray tube. Otherwise, the screen displays the characteristic rainbow due to violations of the motion of electrons. It can burn a thermistor, or a loop. Check the circuit simple. You need to disable, then kerf food. If the light that burned before now gone out, the problem in the chain of lifting capacities. You can test the device, some time will be able to work properly without a loop.
How do you know whether the left or failure PTC loop burned? First, to measure the resistance. In four thermistor inputs. Two heating circuit form a two - remove potential. Between the first pair of resistance will be 300 - 600 ohms, between the second - units ohms. If the disable outputs going to the loop degaussing a cathode ray tube, exclude the portion of the work. Inspection procedure simple. If the lamp is lit with a loop, and no - no, you have to look for a new string. Visually - thick wire covering the cathode ray tube perimeter. To an accuracy of 100% check PTC, vypayat bother. Turn on the power track actions bulbs.
For reference. With the lamp, replace the fuse, long to keep the equipment can not be included. The device is defective, it has more current. Suffice second switching understand lamp is lit or not. After the TV, unplug the power plug. It allows to protect the unaccustomed serviceable load circuit elements.
What else burn? The power supply when entering the large-capacity capacitor, next - the power transistor. Both parts prozvanivatsya. Transistor breaks transition source-drain, although there may be other options. If observed that half of the diode bridge burned, he said eloquently: fuse failed. View TV shows failure: failure in another. But it has already led to the failure of one branch of the diode bridge. Diagnosis is made, the lamp will refuse to light. A key feature of the correct working of the TV is a characteristic hum, indicating: Turn line scanning.
How to repair the TV
Forgot to give general guidance on the TV repaired. The main board is dismantled for convenience, leaving a chance to get even with the electric shock machine is turned off. It seems that no one has died, received burns. Required discharge electrode is a cathode ray tube. It is located under the rubber gasket. Without touching the metal parts of the hands, a screwdriver, pry the rubber, swinging from side to side, remove the electrode. Discharge pin of the housing. If you see a nearby ground loop, get better at it. Clearly, for a successful procedure you need to have on hand with earthing-pin plugs are connected correctly.
When discharging poslyshatsya clicks. Continue to touch the contact, while the phenomenon is observed. In any modern TV electronics collected a board, the head of the operation. Many radioactive elements evaluate the integrity of the visual. Spoiled swell capacitors, resistors (active elements) blacken. Sometimes remains darkened resistance fit. Defect uniquely specifies: radioelement closes the circuit of the broken member.
Repair of LCD TVs recalls the case of models with cathode-ray tube. PTC, of course, is no. Just to understand the cause of failure backlight. In TVs with liquid crystal used two types:
- gas discharge lamp;
- or organic LEDs.
Gas lamps do not like the fellow hanging on the ceiling. Most straws white. To check the power supply, remove the back wall to see the wires that go into the matrix. Carefully disconnect the connector, taking a serviceable lamp, then test. Happens, backlit bit busy with a number of light sources. Matrix bother to remove, turn on the TV, check that the lamp does not work, replace it.
Scheme lighting installation is different. Some TVs require just pull the lamp from the end, without disassembling the matrix. Wiring come from two sides, each covered by a rubber seal. It should move the protective elements, vypayat lamp. Installing a new place in reverse sequence. Try to choose one that is the size equivalent to the original. Location lamp side, at least the top. Sometimes, two or more lighting. If the matrix has vertical or horizontal stripe likely occurred burnout scan electrode. Try to turn the unit on the other, known good die, to test the hypothesis.
Replacement crystals for cheap TVs unprofitable. The cost of new parts above 3000 rubles. Another thing, if the hand similar to a broken television, which has a matrix of liquid crystals in order. Then the change is registered. Repair the TV screen profitable in rare cases.
Meets the characteristic failure of modern television: stepping on the cable. Rip lived, sometimes together with the track on the chip. The digital receiver is represented by a small mikroshemka (which need to screen), so collected is inseparable from the connector. Before repair carefully remove the electronic part. Then use the glue, soldering, restoring detail. Repair of TV antenna is required after being struck by lightning. Users install the plates, lightning forget.
Repairing of plasma TV is the same way. No backlight, PTC, consequently, less problems!