What Does a Computer Repair Specialist Do?

The computer repair industry refers to the repair and maintenance of software problems and hardware problems that occur during the use of desktop notebooks, and the replacement of damaged hardware. This industry requires sufficient cultural knowledge and strong hands-on ability.

Computer repair industry

At present, the global computer market is transforming from desktop PCs to notebooks, and global notebook computer sales have increasingly accounted for the proportion of the computer market. Notebook technology will be more intensive, market demand will be more diversified and personalized, and technology and market changes

Change more quickly, making core technology the focus of competition,

China's current computer maintenance companies are generally divided into three types

[Manufacturer after-sales service department]

The first type is the maintenance and after-sales service department set up by the manufacturer or the agent nationwide. It specializes in providing maintenance for its own products. It is not that its own product is not connected or rarely connected. This is usually set up by large factories and large national agents. . The characteristic is that the maintenance personnel are more proficient in their duties, but are usually not knowledgeable all-round talents. The product information and spare parts at the maintenance point are complete. The products during the warranty period account for most of the workload. Because the maintenance personnel are mostly wage-based, There is less darkness.

The problems of this kind of repair point are that they are generally located in very remote industrial areas. Of course, they can be repaired through the purchased distribution channels, but the time will be longer. Product maintenance costs are more expensive. This is because there are many manufacturers' external maintenance centers that do not really repair. They can only be called spare parts replacement centers. The main task is to replace the faulty parts and return them to the real board manufacturer for repair. He has no maintenance equipment. There is also no chip-level maintenance engineer, so the warranty is good, as long as it is spent to repair, it will be very expensive, and a burst capacitor will dare to charge thousands of dollars for another motherboard. After-sales departments such as boards and cards must have professional equipment to complete localized maintenance.

[Authorized Professional Repair Center]

The second type is a large-scale specialized maintenance company. This category is usually a special maintenance center contracted by one or some manufacturers. These manufacturers do not establish external after-sales service departments themselves, and they are entrusted to professional companies to do, such as IBM notebook repairs. Passage blue express train. This type of maintenance company has many characteristics similar to the first type, which is more formal. In addition to being a manufacturer's repair point, it also connects other products. The technology is more reliable. The product information and spare parts are complete. The disadvantages are the same as the first type. Repair is more expensive. One of our Apple ibook notebooks was broken and sent to a special repair center. They also repaired laptops such as HP and Compaq. The maintenance staff told the editor that this requires a motherboard replacement. If it is not within the warranty period, replacing a motherboard requires Nearly seven thousand yuan. But buying a second-hand ibook is less than half of 7,000! What's even more weird is that the maintenance staff told Xiaobian that repair is free. If they do nt repair, they will have to pay a test fee of 85 yuan. This is because although these companies do not charge customers for the products during the warranty period, they have to start from Signed manufacturers collect money, if customers do not repair, then they will not be able to charge from the manufacturer.

[Personal Repair Merchant]

The third type is a private maintenance company with numerous good and bad essences and dross coexisting in various places in the computer city. This type of company is usually a senior technical engineer with a long time in the factory or special maintenance. In order to make more money, it is established by its own portal. Therefore, it is fair to say that although large repair shops are very professional, the technology is the most sophisticated. The highest maintenance masters are often at private repair points. At the same time, private repair points mainly rely on repairing parallel imports and out-of-warranty and out-of-warranty products. They have the lowest operating costs and the most flexible operation methods (except for a black-hearted repair shop, otherwise they will never change the motherboard for a capacitor). The repair price is the cheapest. Sometimes it is much lower than the first two categories, which is why private maintenance sites are in full swing. The quality and quality of the individual repair points are uneven

However, because the private repair points are all for making money, and they are making money for end users with a poor professional foundation (relatively speaking, the main profit of the second type of companies comes from the contract manufacturers, and the manufacturers are very knowledgeable; as for the first Enterprises, there is almost no need for profit), so all kinds of irregular and ugly phenomena will be seen. Of course, this is not to say that the first two types of companies have no problems in this regard, but that there are fewer opportunities.

Computer maintenance industry check board method

1. Observation method: whether there is burning paste, circuit burning, blistering, board disconnection, and obvious damage to components

2. Meter test method: + 5V, GND resistance is too small (below 50 ohms).

3 Power-on inspection: For clearly broken boards, you can slightly increase the voltage by 0.5-1V, and properly heat the problematic chip after booting, so that the fault is easy to appear.

4 Logic pen check: Check the signal input, output, and control poles of the suspicion for the presence or absence of signal strength.

5. Identify the major working areas: Most boards have a clear division of labor, such as: control area (CPU), clock area (crystal) (frequency division), power supply area, input and output port area, etc. This is very important for in-depth repair of computer boards.

Computer repair industry troubleshooting methods

1. For the chip in question, first check whether there are signals (waveforms) at the input and output terminals according to the instructions of the manual. If there are any errors, check the control signals (clock) of the IC. If this is the case, the IC is bad. There is a great possibility that there is no control signal, and it traces to its previous pole until it finds a damaged IC.

2. Do not remove the same from the pole for the time being, and choose the same model. Or the IC with the same program content is on the back, and turn on to see if it improves, to confirm whether the IC is damaged.

3 Use the tangent or jumper method to find short-circuit lines: find that some letter lines and ground lines, + 5V or other pins that should not be connected to the IC are short-circuited, you can cut the line and measure to determine whether it is an IC problem or a board surface Problems, or borrow signals from other ICs and solder to ICs with incorrect waveforms to see if the phenomenon screen becomes better and judge the quality of the IC.

4 Control method: Find a good computer board with the same content and measure the pin waveform and corresponding number of the corresponding IC to confirm whether the IC is damaged.

5. Test the IC with the ICTEST software in a microcomputer universal programmer (ALL-03 / 07) (EXPRO-80 / 100, etc.).

Disassembly method of computer chip in computer maintenance industry

1. Cut foot method: do not hurt the board, can not be reused.

2. Drag tin method: solder on both sides of the IC pin, use a high-temperature soldering iron to drag back and forth, and simultaneously lift the IC (easy to damage the board, but can maintain the test IC).

3 Grill method: Grill on alcohol lamp, gas stove, electric stove, wait until the tin on the board melts out IC (not recommended).

4 Tin pot method: Make a special tin pot on an electric furnace. After the tin melts, immerse the IC to be unloaded from the board into the tin pot. The IC can be lifted without damaging the board, but the equipment is not easy to make.

5. Electric hot air gun: Use special electric hot air gun equipment to align the hot air port with the IC pin part to be removed, and then the IC after tinning can be lifted out (note that you must master the removable wind speed, wind direction, temperature and other skills to prevent Secondary damage to the original. The air gun has a low cost, usually about 300 yuan, and is one of the tools of choice for most maintenance personnel). ^[2]