Weak current College】 【cathode ray tube monitors (CRT) magnetic principle and workaround】.

<br> <br> The monitor is almost every computer must have the equipment, we opened the computer will be staring at the monitor. If not, we will not be able to keep abreast of the status of the work of the computer. Therefore ., the monitor in the position of the entire computer as our eyes are the Windows of the soul show computer. <br> <br> <br> <br> The monitor as it works in many of the more common types are: cathode ray .tube monitors (CRT) and liquid crystal display (LCD). There are also: plasma display panels (PDP), vacuum fluorescent display (VFD). Ion body panels (PDP), vacuum fluorescent display (VFD) is the new display technology, .but technology is not yet mature and not put into mass production in the market is almost impossible to see. Liquid crystal display (LCD) than a traditional CRT monitor with image is not distorted, flicker-free, non-radiation, etc., but .there are also many of their shortcomings, such as expensive, brightness, low, angle of narrow, slow response. Integrated view, the cathode ray tube monitors (CRT) is the most suitable for ordinary users to buy products. <br> <br .> <br> <br> Although the CRT display and integrated performance and price is good, but it still has some born with defects, such as size, weight, power consumption, radiation strong, vulnerable to magnetic, etc. These disadvantages are the .CRT monitor works, could not be changed fundamentally, the patch only for subsequent improvements or problem occurs before further resolved magnetic phenomenon is a good example. <br> <br> <br> <br> Regular home users and business users to use the .PC environment, always unavoidable other electrical devices and communications equipment. When these devices work, they will become an electromagnetic source, the magnetic field in and around forming a radiation of electromagnetic waves, to form a magnetic field of size and intensity of the radiation from .the device's power of decision. In fact, when a user uses the computer, you often have a number of electrical devices and communications equipment in the work, the computer next to a lot of electromagnetic radiation sources, they constantly transmitting electromagnetic interference the monitor to .work properly. Display manufacturers to address this issue, in the display of plastic enclosures with a layer of metal shielding enclosures, want to eliminate electromagnetic interference. However, due to the monitor in the work of the calorific value is large, so the metal shielding .enclosures must set aside a certain gap for heat dissipation. In this way, electromagnetic interference you can still enter by these gaps, the monitor inside the metal shielding enclosures can only serve to reduce interference, which could not completely solve the problem of electromagnetic interference. .Worth mentioning is that many manufacturers in the design and production of low-end monitors, in order to reduce costs, simply cancel the metal shielding enclosures, allowing interference problems. Unfortunately these no metal shielding enclosures of the low-end user, monitor the general .consumers, in very large. <br> <br> <br> <br> So it seems, the cathode ray tube monitors magnetized problem is pervasive. CRT monitors have been magnetized, display of the image is distorted, swaying, screen does not .display. In this case, there must be degaussed the monitor. <br> <br> <br> <br> To monitor degaussed the monitor, you must first understand the principle appears. We know of CRT monitors its light principle is: when .the picture tube internal gun cathode electron issued <br> The intensity control, focus and accelerated into tiny electronic flow, through DeflectionCoil (deflection coil) role to correct deviations from the target, through the small hole or fencing mask, bombarding the phosphors on the .screen. At this point the phosphor is activated, it emits light. R, G, B 3-color fluorescence is the intensity of the different proportions of electron flow, will produce a variety of colors. One and the magnetization monitor is DeflectionCoil (deflection .coil). It is used for the positioning of the electron gun Launcher, powerup can produce a strong magnetic field, by changing the magnetic field strength to move the gun. In this way, next to the monitor electromagnetic interference sources on magnetic deflection yoke, .will change its strength and direction. Due to the magnetic field strength and deflection yoke orientation is disrupted, gun transmitter location offset occurs, allowing the electronic flow out from the original track, ranging from the screen produce artifacts, the cause of the disorder. Magnetization .because CRT display problem, some monitors manufacturer has a product increases the degauss feature, usually in the monitor's main menu (MAINMENU) DEGAUSS option that is. Perform DEGAUSS, monitor screen will start to violent shaking and accompanied by a large current sound. About in .a few seconds later, swaying and current sound at the same stop, degaussing. Monitor the degauss feature on general temporary magnetic has good effect, use more convenient, but after the strong magnetic field interference caused by the strength of the magnetic susceptibility. For strong .electromagnetic interference magnetization of the monitor, it is best to use a special degaussing equipment, such as degaussing rods and degaussing coil. <br> <br> <br> <br> Degaussing rods for monitor production of magnetization of a short Rod-like .device, in the General e-markets have sales. When you use the monitor screen holders prior to the screen Center as the Centre do radius of the circular motion, gradually enlarge until degaussing. As a result do not clear can be done a few times .. Degaussing a great advantage is the purchase and use are very easy, normal consumers can correct operation. <br> <br> <br> <br> Degaussing coils with magnetic induction principle: is the application through the coil alternating current in the coil .Geometry Center produces an alternating magnetic field, use the alternating magnetic field on the display in the geometrical Center of cathode degaussed, thus the purpose of achieving degaussing. Use the degaussing coils degaussed, handheld coil, stuck to the screen from one edge to the Centre .slowly in a circular motion, arrived at the screen Center and then, in turn, to the outer ring rotates, such asThis repeated multiple times. The end of the operation, the coil on the center of the screen, and the screen surface into a .90-degree angle, perpendicular to the ground slowly back to the monitor, and then close the 1m power supplies, power back up and carefully observe the degaussing. As a result of the poor, can be repeated until the complete elimination of the monitor was .magnetized. Degaussing coil's advantages are more obviously effect (personal opinion), the disadvantage is that the procedure is no more a simple Rod degaussing. <br> <br> <br> <br> Degaussing coil has a big advantage is making simple, .ordinary computer player can make one yourself, as long as the attention to detail, made out of the effect of degaussing coils or very good. Own production of degaussing coils, both to save maintenance costs, and action by yourself, but also allows the operator .to obtain the fun and sense of DIY, why? <br> <br> <br> <br> Self-made degaussing coils required to prepare material is: a few metres of wire, a round plastic box, insulated electric blanket, insulated .rod (1 m), etc. Produced by wire (plastic wire or plastic insulated wires) parallel around circular plastic box, bearing in mind the winding turns, not too little, or generated by the magnetic field is too small, no actual effect; .turns nor too much, otherwise the resulting magnetic field is too strong against the surrounding the negative electricity equipment. Actual operation as long as you are finished around several meters prepared, not enamelled wire is too much or too little. Winding, insulation blanket wrap will .be pasted to the round plastic box, paste the two to three layers (at least two layer, paste will round plastic box and enameled wire surface paste all good), so that the plastic box and enameled wire fixed together. Next, you will place .one end of an insulating Rod has fixed the circle on the side of the plastic box, paste with insulated electric blanket. Finally, the wire's head-line in a large load of household appliances (such as furnaces, heaters or electric rice cooker) or .remove obsolete monitor the degaussing coils dedicated resistance. The degaussing coils series in large load electric or private resistance, in order to reduce the degaussing coil in the use of current intensity to reduce the heat. Otherwise, when degaussing coil, its calorific value great, .very easy to burn through wire insulation, causing a short circuit. However, reducing the current in the circuit, will allow the degaussing coil magnetic field strength decreases, degaussing effect is not evident, the solution is to increase the winding wire turns. The increase .in the number of turns of wire, it should be noted that the above mentioned turns on the effect of magnetic field size. <br> <br> Use the load is big, electrical access utility in degaussing coils in current will make the next generation .magnetic degaussing coil. The user does not have a handheld insulated rod and degaussing coils connected end to monitor degauss. Specific operational methods have been mentioned above. <br> Now let's summarize the production and use of degaussing coil considerations: <br> First, .the size of the degaussing coils should be used to match the CRT monitor; <br> 2. insulation blanket tape layer for at least two layers to ensure insulation effect; <br> 3. in weighing the degaussing coils of heat output and the desired .field strength after degaussing coil ampere-turn (AT value); <br> If conditional, degaussing coils circuit series a thermistor, degaussing coils as you work, will automatically resize depending on the operating temperature to ensure that the use of current values. Thermistor .resistance temperature limit and is dependent upon the system of degaussing coils of wire length and circuit in the series of large load appliances to determine; <br> 5. use should avoid damage the insulation, ensure the safety of degaussing coil <br> VI. .use should use insulated bar, it is best not to touch by hand; if degaussing coils noted above, make a good performance and uses highly secure degaussing coil is not difficult. <br>.