Equipment used for diagnosis and maintenance of computers

Often, just a tool kit and a small collection of software will not be sufficient to meet specialized professional support in certain calls, especially if they occur in the field. For this he needs to have a specialized laboratory for assembly and maintenance of computers, where you will find all the resources necessary for the full development of activities. Especially, equipment for diagnostics and general maintenance.

This is the digital multimeter, the best friend of Technical Support! ;-)

One time before, had written an introductory material on the plates POST . Although they carry the status of devices able to diagnose and resolve the anomalies that prevent a desktop PC restart, they do nothing more than display the Post On Self Test tests performed by the BIOS, and some details about what failed. There are even cards designed for diagnosis, but they have certain special features so advanced that only remind us of the plates POST due to its format and usage possibilities. Yet, however advanced they are, they do not solve everything ...

Other equipment will be needed. For example, many anomalies are not linked directly to your desktop, but its power supply. While many coaches are limited to removing the suspect component and give a match without charge to verify their operation (via a clip, connect pins 3 and 4 of the connector and connect the outlet), we often need to perform measurements of voltages food, in order to check that they are actually being provided. Come into play, testers sources.

Some models are very basic, only the signaling voltage power supply, others are a bit more sophisticated (like this photo illustration), with a small LCD panel that advises the measurements, allowing us to see if they are within the allowable variance (10%). However, to have full assurance that the power supplies are tested to operate even though they need to be loaded, problematic because many sources only show their weaknesses when they are actually working full steam ahead! For this, load testers are ideal equipment to meet this need.

Because they are relatively expensive equipment, load testers are often used by laboratories specialized in conducting the reviews, benchmarks and certification of equipment, ensuring that they really do "what they say," according to the specifications reported by the manufacturers. Already a simple laboratory installation and maintenance, electronics experts set up an arrangement where connectors interconnected using one or more bulbs to test them. As I am not an electronics expert, I leave to the experts comment on the subject, but now, you go forward I think this a nice workaround (or better, "Brazilian way")! ;-)

After making sure the proper functioning of the power supply and ensure that it is not the cause of the malfunction of the desktop (except when it is badly scaled), it is time to conduct a close inspection of the motherboard, since it is naturally the next suspect. And after a visual analysis of its external components (to ensure no broken connectors, capacitors, stews, broken trails, dirty contacts and other anomalies of the genre), plus new equipment comes into play: the oscilloscope. Basically, its function is to allow the display of waveforms of electrical signals from components of the motherboard, allowing to diagnose the defective ones from the "behavior" of these signals.

At this point, it goes without saying that the coach should be specialized in digital electronics, as well as should have all the information related to the components of a motherboard. Naturally, this process will be a much more accurate measurement, compared with the possibilities of using a simple digital multimeter, so do not be surprised to know that the oscilloscope is an expensive equipment by nature, where good model is costing something around 2 to 3 thousand dollars.

But now, let's assume that a problem was encountered in a specific chip on the motherboard, in which the solution would be to remove the flawed model for replacement. As such chips are soldered directly on board, we only use sufficient a soldering iron to do the job, right? Not so. Because the format of the contact - which can be numerous "legs" to the system BGA (ball) - will be necessary to use a welding station for carrying out this work.

Also called SMD rework station, what it basically does is generate and concentrate the heat on the chip, as soon as the heat is directed across the board, will be performed by fusion welding. Once the material used in the solder paste has very low melting point, will not take long to weld (or remove) the chip in question. Generally, equipment is cheap, costing somewhere around $ 500.00, but even so, they need not "suspicious" of efficiency, because they are relatively efficient equipment in their proposal. Still, there are far more sophisticated models, where they use infrared lasers instead of hot air to concentrate the heat.

Possible defects in a motherboard may have, in many cases we find the corrupted BIOS firmware, which will force us to do the remake of this for the system (desktop PC) can be started without any problems. But that is the question: rewrite of the software (BIOS or even the BIOS setup, if offers the option) will need the system up and running so they can make rewriting the BIOS! For these cases, there are special devices that allow removing the BIOS chip for its remake: the (re) writers BIOS, also known as EEPROM reprogrammed.

Not much mystery, these devices can make rewriting the BIOS chip without major difficulty, namely that the chip is embedded in one of the available slots, and through the burning software that came with the device (CD-ROM, along with documentation), performing the recording process. Of course, not only the firmware should be compatible with the motherboard in question (downloaded from the website or obtained by the media provided by the manufacturer), but the chip will also be supported by the device in use. Obviously, a closer look at their documentation will reveal what are the DIP chips supported. Overall, the price is around $ 300.00.

Anyway, these are the most common equipment found in laboratories maintenance oriented electronic computers in general. Those interested in having a specialized laboratory "real" need to know that a lot of money to invest the necessary resources. They are not thinking of practicing maintenance over a makeshift kitchen table, right? In fact, not only in equipment and devices of the genre, but also the local infrastructure should be built to accommodate all these materials. Focus on the bench and electrical grounding strap, and cabinets for storage of spare parts and consumables.