Nine, keyboard
The keyboard is a variety of ways in the process of use, and it is also a variety of reasons. There is a poor failure, there is a mechanical failure of the button itself, and there is a fault such as logic failure, duct welding, fake welding, demondering and metal hole oxidation. When repairing the analysis, the analysis is determined according to different faults, finding the cause of failure, and performs corresponding repairs.
Common faults 1: "Card key" fault in the keyboard
There are some keys on the keyboard, such as the space bar, the Enter key does not work, sometimes you need to enter - one or two characters in countless times, some keys, if the cursor keys are not up, the cursor is continuously moved on the screen. At this time, other characters of the keyboard cannot be entered, and you need to play once again.
This fault is a "card button" fault of the keyboard, not just the old keyboard for a long time, there is a few new keyboards that don't have a new keyboard, and the keyboard's card key fault has sometimes happened. The phenomenon of the keyboard is mainly caused by the following two reasons:
One reason is that the position offset under the keycap is caused to cause the keycap to push up the keyboard cannot bounce with the keyboard, which occurs in the new keyboard or on the shorter keyboard.
Another reason is that after the button is used for a long time, the reset spring elasticity becomes very poor, and the shrapnel becomes larger, and cannot make the button bounce, which occurs in the long-term use of the keyboard. When the keyboard appears at the card button, you can dial the key cap and press the rod. If you can't put it or fat up by the rod, it is caused by the second cause, otherwise it is caused for the first reason. If the keycap is causing a "card button" failure due to the reasons of the keycap and the key body casing, you can put a gasket between the keycap and the bond, which can be slightly hard (such as the waste-free soft magnetic disk jacket) Made, the size is equal to or slightly larger than the size of the bond, and opens a square hole that allows the ammonium rod to pass free to pass through the position, and insert the keycap; use this gasket Blocking the keycap and the key body can be kept to the fault button; if it is caused by the cause of spring fatigue, the splinter resistance is caused, the bond is opened, and the bond is opened, slightly stretched the reset spring to restore the elasticity; The bullet is restored. By removing the shrapnel, reduce the resistance of the rolling, so that the fault button is recovered.
Common faults 2: Some characters cannot be entered
If only a key character cannot be entered, it may be that the button fails or solder joint soldering. When checking, open the keyboard according to the method described above, and measure the interworking state of the contact with the multimeter. If the key is pressed, it will be noted that the button spring is fatigue or contact, it needs to be repaired or replaced; if the key is pressed, the contact is turned off, and it may be due to the duly welding, dewrapping or golden shaped oxidation. To, it can be measured in a printed line, and the fault can be found. If the metal hole is oxidized, the oxide layer can be cleaned, then the re-welding; if the metal hole is completely detached, it can be used. The soldering lead is connected.
Common faults 3: If there are multiple not in the same column, it is not possible to enter the buttons of the same line.
It may be a line or routine to break, or may be a logical gate circuit to fail. At this time, you can use a high-frequency oscilloscope of 100 MHz to detect, find a malfunction solder point, and then repair. Common fault four: The keyboard input is inconsistent with the character displayed. Such faults may be due to generating short-circuit phenomena on board, but the performance is displayed as other characters of the same column, at which point the multimeter or oscilloscope can be measured to determine the fault point.
Common faults 5: Press a key to generate a string of various characters, or click the button when pressing
This phenomenon is caused by a logic circuit failure. First select a column character, if you don't contain a row of back keys, it is possible to generate multiple other characters; if it is a column containing the back-to-turn, it will generate a character and cannot be finally entered the system. The oscilloscope checks the logic circuit chip, finds the new chip of the same model after the fault chip is found, and the fault is excluded. Ten, mouse
The fault analysis and maintenance of the mouse is relatively simple, most of the fault is the interface or button contact with poor contact, disconnection, mechanical positioning system. A small number of faults are mouse internal components or circuit bread welding, which is mainly in certain inferior products, especially in light-emitting diodes, and IC circuits are damaged.
Common faults 1: Can't find the mouse
1. The mouse is completely damaged and needs to replace the new mouse.
2. The mouse is poor contact with the host connection serial port or PS / 2 mouth. After carefully picking up, you can restart.
3. The serial port or PS / 2 mouth on the motherboard is rarely seen. If this is the case, you have to replace a motherboard or use the serial port on the multi-function card.
4. The mouse line is poor contact, which is the most common. Poor contacts are mostly in the interior of the mouse and the connection of the board. The failure is not difficult to repair it in the PS / 2 connector. It is usually because the line is relatively short, or the mouse line is pulled by force, and the solution is to open the mouse, and then weld the solder joint. In addition, there is a poor contact in the mouse line, which is caused by aging due to time, which is often difficult to find, and replacing the mouse is the fastest solution.
Common faults 2: Mouse can be displayed, but cannot be moved
The flexibility of the mouse decreases, the mouse pointer is not as desired as before, but the reaction is slow, and the positioning is not accurate, or simply cannot move. This situation is mainly due to the loss of excessive dirt due to the mechanical positioning rolling axis in the mouse, causing the transmission failure, causing the scrolling. The maintenance focuses on the transmission of the X-axis and the Y-axis of the mouse. The solution is that the gel lock can be opened, and the mouse roll the mouse, and the rubber ball is cleaned with a clean cloth, and the friction shaft or the like can be wiped with alcohol. It is best to drop a few drops of sewing machine oil at the axial heart, but must be carefully, don't flow on the friction surface and the yards. After cleaning all dirt, the flexibility of the mouse is restored.
Common fault three: mouse button failure
1. The mouse button has no action, which may be because the mouse button and the micro switch distance on the board are too far or click on the switch through a period of time, and the rebound capacity is lowered. Unpack the mouse, attach a thickness plastic sheet below the mouse button, and the thickness is determined according to the actual needs, and it can be used after processing.
2. The mouse button cannot bounce normally, which may be because the plastic reed is easily broken after the bits of the bowl of the bowl of the in-line switch is in the button, especially the plastic reed is long. If it is a three-key mouse, then the middle of the key can be urgent. If it is a quality original brand name, it can be welded, remove the micro switch, carefully cleans the contact, and after the grease is loaded, it can be used.
