Sofa butler tips coup We often encounter the situation where the TV has no sound, but a large part of the users do not know how to solve this problem. In fact, we can solve it by ourselves. Today, Xiao Bian brought everyone a sound image-free repair method for Konka TV. It is not necessary to find maintenance personnel.
The cause of the failure:
1. If there is only some noise with no image after turning on the TV, this situation is likely to cause problems in the tuner and the middle. According to the working principle of the television, this reason causes the sound to have no picture, the picture tube can show the machine setting menu, audio and video interface, and can play external audio and video signals.
2. The second case is the sound of a normal TV show but no picture. This shows that the high-frequency, intermediate-frequency, and audio circuits are in normal operating conditions, and there is no fault in the short circuit of the output circuit. If the screen can display the TV settings menu, then this problem is likely to be due to the sound separated into the video playback section.
3. There are also situations where the sound is normal, but there is no on-screen menu. In this case, you can turn on the brightness and contrast of the TV, pay attention to the condition of the screen, and turn off the TV. If you see a flash of light on the screen at the moment you turn it off, with a slight discharge, you can be sure that the picture tube is OK. At this time, it depends on whether the picture tube filament is bright or not.
4. If it is a TV with a remote control, it may be possible to lose the image due to the failure of the CPU chip.
5, the power circuit is not normal, the performance of the panel when pressing the button without any reaction, the indicator light does not shine. First check the normal 12V voltage, follow the check 5V voltage, because the A/D driver board signal processing part of the chip's operating voltage is 5V, so find the machine can not open the fault, first use a multimeter to measure 5V voltage, if there is no 5V If the voltage or 5V becomes very low, then there may be a problem with the input stage of the power circuit.
In other words, the 12V to 5V power supply part of the problem, this failure is very common, usually burn insurance or voltage regulator chip failure, some machines are built-in switching power supply, output two sets of power, one of which is 5V is used for signal processing, and the other group is 12V to provide high voltage board point backlight. If some parts of the switching power supply circuit fail, it may result in no output of the two groups of power supplies.
Another possibility is that the 5V load is getting heavier. The 5V voltage is pulled very low. In other words, the signal processing circuit at the rear stage has a problem, some of the circuits are damaged, and the load is aggravated, pulling the 5V voltage. Very low, one by one after the investigation of the problem of the components after the problem, replace the failed components, 5V can return to normal, the fault is generally resolved, but also often encountered after the 5V voltage returned to normal after the normal boot.
This situation also has a variety of reasons. On the one hand, the MCU program may be washed out, which may lead to no boot. There is also damage to the MCU itself. For example, the I/O port of the MCU is damaged and the MCU cannot scan the keys. The failure caused by the MCU, in the case of no way to find the replacement of the original AD driver board, can only find another way to find the A/D driver board that can be replaced.
6, the power is normal, may have a problem driving the backlight circuit. The detection method is to connect the monitor to the host boot check, close to the screen carefully observed, if you see the display is very dark images, it proves that the A / D driver board signal processing part of the circuit is normal, the problem is locked in the drive Backlight high voltage board and control high voltage board switch function circuit, the common fault of the high voltage board has the high voltage board's own insurance burn out causing no 12V supply and switch chip failure and so on.
7, AD board control high voltage board switch part of the circuit is faulty, can not be output high to control the switch pin of the high voltage board, with a multimeter negative test lead ground, the test lead is received control output pin, press the switch button, normal words It can be seen that there is a level change, but also can use a relatively simple method to determine whether the high voltage board is not good, that is to find the control of the high voltage board switch directly to the 5V voltage, high voltage board is not faulty Can light the backlight.
Another situation will cause a black screen, that is, the backlight of the screen is broken, but if it is a dual-lamp and four-lamp screen backlight at the same time bad is not possible, broken one of the lamps will cause a black screen, but with the black screen failure in front of The performance is different. This is because some high-voltage boards have unbalanced load protection. If a lamp is broken, the high-voltage board will enter the unbalanced load protection state after power on, and it will appear as a black screen after flickering.
Maintenance method:
1. Listen to the high-voltage sound of the start-up: If there is a description, the circuit work is basically normal (note that it is basically normal), and if not, the line circuit is not started.
2. Observe whether the display tube filament emits light: at this time, slowly adjust the knob on the high voltage pack while observing the screen changes. There are roughly three situations:
(1) No change, indicating that the cathode voltage of the cathode of the kinescope is abnormal; check whether the 200v visual discharge power supply is normal.
(2) Vertical one bright line because of the open circuit of the horizontal deflection coil or the phenomenon of false welding in the solder joint.
(3) There is a bright line at the level, and there are many reasons. In addition to the open circuit of the field deflection coil or the welding of the welding spot or the welding of the field output block, the signal transmission circuit of the field oscillation and the field output may cause malfunction;
Maintenance Notes:
1. It is necessary to clarify the fault condition of the faulty TV before repairing. Whether it is to repair the customer or repair it to relatives and friends, this should be taken into account. To avoid being misunderstood is to erode it.
2. How to find out the fault condition of the faulty TV during the repair?
(1) Ask the specific fault phenomenon. The process of the fault is sudden or gradual. What is the status? It is helpful to analyze the cause of the fault.
(2) Ask if the color TV is turned on and whether someone else has repaired it. Asking these questions will allow you to determine whether you can power up the TV in front of the owner. To find out the fault condition of the faulty TV, it is better to be able to watch the TV on the front of the owner, and then open the case and observe it carefully.
(3) For the "three-nothing" TV, after opening the casing, it is necessary to observe whether there is any problem with the diameter of the CRT. You can use your hand to squat a few times, because some of the broken diameter will be fixed by the deflection yoke. It also depends on whether the circuit board has obvious breaks, large area burns, and other serious phenomena.
3, do not use thin copper wire or large container fuse to replace the sub-fuse, especially after the fuse is burned, do not replace the test machine immediately, otherwise it will burn other originals. If you replace some components, be careful to keep the same parameters as the original components.
4, can not use the discharge method to check the high voltage, or the discharge current is too large to the TV output line tube or high-voltage rectifier components damage. For the maintenance of the line output, the pass capacitor cannot open circuit test, it is easy to burn out components.
5, when the resistance problem needs to be replaced, pay attention to the resistance, power and the original resistance.
6. If there is a problem with the kinescope, if there is a bright line or bright spot on the screen, the brightness should be turned off to prevent the fluorescent layer of the kinescope from being burned. Be careful when replacing the display tube. Wear explosion-proof glasses or goggles to prevent the shell from bursting.
The cause of the failure:
1. If there is only some noise with no image after turning on the TV, this situation is likely to cause problems in the tuner and the middle. According to the working principle of the television, this reason causes the sound to have no picture, the picture tube can show the machine setting menu, audio and video interface, and can play external audio and video signals.
2. The second case is the sound of a normal TV show but no picture. This shows that the high-frequency, intermediate-frequency, and audio circuits are in normal operating conditions, and there is no fault in the short circuit of the output circuit. If the screen can display the TV settings menu, then this problem is likely to be due to the sound separated into the video playback section.
3. There are also situations where the sound is normal, but there is no on-screen menu. In this case, you can turn on the brightness and contrast of the TV, pay attention to the condition of the screen, and turn off the TV. If you see a flash of light on the screen at the moment you turn it off, with a slight discharge, you can be sure that the picture tube is OK. At this time, it depends on whether the picture tube filament is bright or not.
4. If it is a TV with a remote control, it may be possible to lose the image due to the failure of the CPU chip.
5, the power circuit is not normal, the performance of the panel when pressing the button without any reaction, the indicator light does not shine. First check the normal 12V voltage, follow the check 5V voltage, because the A/D driver board signal processing part of the chip's operating voltage is 5V, so find the machine can not open the fault, first use a multimeter to measure 5V voltage, if there is no 5V If the voltage or 5V becomes very low, then there may be a problem with the input stage of the power circuit.
In other words, the 12V to 5V power supply part of the problem, this failure is very common, usually burn insurance or voltage regulator chip failure, some machines are built-in switching power supply, output two sets of power, one of which is 5V is used for signal processing, and the other group is 12V to provide high voltage board point backlight. If some parts of the switching power supply circuit fail, it may result in no output of the two groups of power supplies.
Another possibility is that the 5V load is getting heavier. The 5V voltage is pulled very low. In other words, the signal processing circuit at the rear stage has a problem, some of the circuits are damaged, and the load is aggravated, pulling the 5V voltage. Very low, one by one after the investigation of the problem of the components after the problem, replace the failed components, 5V can return to normal, the fault is generally resolved, but also often encountered after the 5V voltage returned to normal after the normal boot.
This situation also has a variety of reasons. On the one hand, the MCU program may be washed out, which may lead to no boot. There is also damage to the MCU itself. For example, the I/O port of the MCU is damaged and the MCU cannot scan the keys. The failure caused by the MCU, in the case of no way to find the replacement of the original AD driver board, can only find another way to find the A/D driver board that can be replaced.
6, the power is normal, may have a problem driving the backlight circuit. The detection method is to connect the monitor to the host boot check, close to the screen carefully observed, if you see the display is very dark images, it proves that the A / D driver board signal processing part of the circuit is normal, the problem is locked in the drive Backlight high voltage board and control high voltage board switch function circuit, the common fault of the high voltage board has the high voltage board's own insurance burn out causing no 12V supply and switch chip failure and so on.
7, AD board control high voltage board switch part of the circuit is faulty, can not be output high to control the switch pin of the high voltage board, with a multimeter negative test lead ground, the test lead is received control output pin, press the switch button, normal words It can be seen that there is a level change, but also can use a relatively simple method to determine whether the high voltage board is not good, that is to find the control of the high voltage board switch directly to the 5V voltage, high voltage board is not faulty Can light the backlight.
Another situation will cause a black screen, that is, the backlight of the screen is broken, but if it is a dual-lamp and four-lamp screen backlight at the same time bad is not possible, broken one of the lamps will cause a black screen, but with the black screen failure in front of The performance is different. This is because some high-voltage boards have unbalanced load protection. If a lamp is broken, the high-voltage board will enter the unbalanced load protection state after power on, and it will appear as a black screen after flickering.
Maintenance method:
1. Listen to the high-voltage sound of the start-up: If there is a description, the circuit work is basically normal (note that it is basically normal), and if not, the line circuit is not started.
2. Observe whether the display tube filament emits light: at this time, slowly adjust the knob on the high voltage pack while observing the screen changes. There are roughly three situations:
(1) No change, indicating that the cathode voltage of the cathode of the kinescope is abnormal; check whether the 200v visual discharge power supply is normal.
(2) Vertical one bright line because of the open circuit of the horizontal deflection coil or the phenomenon of false welding in the solder joint.
(3) There is a bright line at the level, and there are many reasons. In addition to the open circuit of the field deflection coil or the welding of the welding spot or the welding of the field output block, the signal transmission circuit of the field oscillation and the field output may cause malfunction;
Maintenance Notes:
1. It is necessary to clarify the fault condition of the faulty TV before repairing. Whether it is to repair the customer or repair it to relatives and friends, this should be taken into account. To avoid being misunderstood is to erode it.
2. How to find out the fault condition of the faulty TV during the repair?
(1) Ask the specific fault phenomenon. The process of the fault is sudden or gradual. What is the status? It is helpful to analyze the cause of the fault.
(2) Ask if the color TV is turned on and whether someone else has repaired it. Asking these questions will allow you to determine whether you can power up the TV in front of the owner. To find out the fault condition of the faulty TV, it is better to be able to watch the TV on the front of the owner, and then open the case and observe it carefully.
(3) For the "three-nothing" TV, after opening the casing, it is necessary to observe whether there is any problem with the diameter of the CRT. You can use your hand to squat a few times, because some of the broken diameter will be fixed by the deflection yoke. It also depends on whether the circuit board has obvious breaks, large area burns, and other serious phenomena.
3, do not use thin copper wire or large container fuse to replace the sub-fuse, especially after the fuse is burned, do not replace the test machine immediately, otherwise it will burn other originals. If you replace some components, be careful to keep the same parameters as the original components.
4, can not use the discharge method to check the high voltage, or the discharge current is too large to the TV output line tube or high-voltage rectifier components damage. For the maintenance of the line output, the pass capacitor cannot open circuit test, it is easy to burn out components.
5, when the resistance problem needs to be replaced, pay attention to the resistance, power and the original resistance.
6. If there is a problem with the kinescope, if there is a bright line or bright spot on the screen, the brightness should be turned off to prevent the fluorescent layer of the kinescope from being burned. Be careful when replacing the display tube. Wear explosion-proof glasses or goggles to prevent the shell from bursting.
H1Z2Z2-K Solar Cable is a type of cable specifically designed for use in solar power systems. It is commonly used to connect solar panels to inverters and other electrical components in a solar installation.
The H1Z2Z2-K designation refers to the cable's technical specifications. The "H1" indicates that it is a harmonized cable, meeting European standards. The "Z2" indicates that it is a halogen-free cable, which means it does not emit toxic gases when exposed to fire. The "Z2" also indicates that it is resistant to UV radiation, making it suitable for outdoor use in solar applications. Finally, the "K" indicates that it has a flexible copper conductor.
H1Z2Z2-K solar cables are typically insulated with cross-linked polyethylene (XLPE) or ethylene propylene rubber (EPR) to provide excellent electrical insulation and resistance to environmental factors such as sunlight, heat, and moisture. They are also often double-insulated for added safety.
These cables are available in various sizes and can handle different current ratings, depending on the specific requirements of the solar system. They are designed to withstand the harsh conditions of outdoor environments and have a long service life.
Overall, H1Z2Z2-K solar cables are essential components in solar power systems, ensuring efficient and reliable electricity transmission from the solar panels to the rest of the system.
When installing H1Z2Z2-K solar cable, it is important to follow the manufacturer's guidelines and local electrical codes to ensure proper installation and safety.
Tinned Copper Solar Pv Cable,Pv Solar Power Cable,Twin Dc Solar Cable,Dc Solar Cable
Ruitian Cable CO.,LTD. , https://www.rtpowercable.com