Repair
pc monitors
repair of a personal computer is usually very simple, due to its modular architecture, if, for example, a floppy drive starts to show problems, it is easier and cheaper to purchase a new try to repair it, but There is an element in the PC whose importance and cost is so high that in cases of failure if appropriate try to rescue: the monitor. This article will discuss the basics of service to these output peripherals, assuming the reader already has the required computer concepts and knows the role of video card.
tools and instruments necessary for the service PC Monitor
Before installing the description of the method of fault detection, see what are the appropriate instruments and tools to service these devices.
1) Computer PC armed and running. We can not properly check the operation of a computer monitor, if not we have a PC armed and working properly as the signal source deployment.
2) Essential for the service monitors, digital multimeter.
3) Another necessary tool for the service to monitor the oscilloscope, with which we can trace the path of the various signals on their circuits.
4) While not a device strictly necessary, it is recommended to have a frequency meter.
5) Of course, all electronic service shop should have common tools such as screwdrivers, pliers, soldering and welding equipment, degaussing coil, etc..
6) No less important are the service manuals of brands and models most common monitors.
If you have all this, service to PC monitors will be relatively simple, and more if it follows the fault detection method that we describe below.
fault detection method.
Let's see what the logical steps to follow in the diagnosis a computer monitor. Power Supply
For anyone connected with electronics, it is obvious that the first element to be checked is the source of power, do not forget that in this block which produce the voltages required for proper operation of the circuits a monitor ..
Then when you get to your shop a monitor with problems, the first thing to check is the operation of the power supply. If all this works smoothly, we can be reasonably sure that the problem is somewhere else in the unit.
Control System (Syscon)
The next block to be reviewed during the diagnosis task is system control and syscon: this circuit closely monitors the performance of almost all the blocks within the monitor. Syscon
The heart and a microprocessor, which has within it a low-power microprocessor, surrounded by supporting elements (input and output ports, circuits, timers, RAM and ROM, etc.).: And all this comes together encapsulated in a single integrated circuit, low-cost, manufacturers have been able to incorporate into their designs without impacting too much on public money. Stage
horizontal sync
might think that once ruled the power supply and the microcontroller, the first thing we would to do is start tracking the color signals to the monitor, but it is better to start with the horizontal sync phase, because in its output are the high voltage transformer.
As mentioned, the horizontal sync pulses coming directly from the video card that is, you just have to get them to the horizontal oscillator to generate the ramp, sending the driver H & H finally reach the exit, where they are connected both the deflection yoke and the Fly-Back. Stage
vertical sync
If you checked properly the operation of stage H of the monitor, now check the performance of stage V. Compared with the block H, managing the vertical bar is surprisingly simple, so it will not cost you more work to track the different signals within this section, and detect any abnormalities from the V input pulses to the generation of V sweeps that are sent to yokes. Color Management
We left the final stage of color management, because a bug in it does not block the overall operation of the system (a problem that they can generate all the other blocks), in the worst case We face a monitor on, which has trace on the screen, but growing video information.
To diagnose the stage. Just use a oscilloscope faith to make a crawl from the entrance of the video card to output amplifiers color, the goal is to ensure that the signal suffers no defects or lost at any given time.
Kinescope .
We left the final appearance of screen, with the understanding that it is considered failure in this device, for example, a magnetized shadow mask, purity and convergence errors, failure to focus, etc. And given that these problems can be eliminated by methods already known to all electronic service technician, not expand on the subject. If you find a defective picture tube, it is best to suggest to the customer buy a new monitor, the reason is that as these devices are highly accurate, are generally not well when they are "repaired" (plus the cost of a new picture tube is almost equal to that of a new monitor).
As you can see, the steps for troubleshooting on monitors is well structured, ranging from those blocks that directly affect the overall operation of the system to others who may presentarfallas hardly noticeable.
We recommend you practice on various makes and models of monitors, and you will see that all the steps are the same.
And do not forget to apply the hypothetical-deductive!
pc monitors
repair of a personal computer is usually very simple, due to its modular architecture, if, for example, a floppy drive starts to show problems, it is easier and cheaper to purchase a new try to repair it, but There is an element in the PC whose importance and cost is so high that in cases of failure if appropriate try to rescue: the monitor. This article will discuss the basics of service to these output peripherals, assuming the reader already has the required computer concepts and knows the role of video card.
tools and instruments necessary for the service PC Monitor
Before installing the description of the method of fault detection, see what are the appropriate instruments and tools to service these devices.
1) Computer PC armed and running. We can not properly check the operation of a computer monitor, if not we have a PC armed and working properly as the signal source deployment.
2) Essential for the service monitors, digital multimeter.
3) Another necessary tool for the service to monitor the oscilloscope, with which we can trace the path of the various signals on their circuits.
4) While not a device strictly necessary, it is recommended to have a frequency meter.
5) Of course, all electronic service shop should have common tools such as screwdrivers, pliers, soldering and welding equipment, degaussing coil, etc..
6) No less important are the service manuals of brands and models most common monitors.
If you have all this, service to PC monitors will be relatively simple, and more if it follows the fault detection method that we describe below.
fault detection method.
Let's see what the logical steps to follow in the diagnosis a computer monitor. Power Supply
For anyone connected with electronics, it is obvious that the first element to be checked is the source of power, do not forget that in this block which produce the voltages required for proper operation of the circuits a monitor ..
Then when you get to your shop a monitor with problems, the first thing to check is the operation of the power supply. If all this works smoothly, we can be reasonably sure that the problem is somewhere else in the unit.
Control System (Syscon)
The next block to be reviewed during the diagnosis task is system control and syscon: this circuit closely monitors the performance of almost all the blocks within the monitor. Syscon
The heart and a microprocessor, which has within it a low-power microprocessor, surrounded by supporting elements (input and output ports, circuits, timers, RAM and ROM, etc.).: And all this comes together encapsulated in a single integrated circuit, low-cost, manufacturers have been able to incorporate into their designs without impacting too much on public money. Stage
horizontal sync
might think that once ruled the power supply and the microcontroller, the first thing we would to do is start tracking the color signals to the monitor, but it is better to start with the horizontal sync phase, because in its output are the high voltage transformer.
As mentioned, the horizontal sync pulses coming directly from the video card that is, you just have to get them to the horizontal oscillator to generate the ramp, sending the driver H & H finally reach the exit, where they are connected both the deflection yoke and the Fly-Back. Stage
vertical sync
If you checked properly the operation of stage H of the monitor, now check the performance of stage V. Compared with the block H, managing the vertical bar is surprisingly simple, so it will not cost you more work to track the different signals within this section, and detect any abnormalities from the V input pulses to the generation of V sweeps that are sent to yokes. Color Management
We left the final stage of color management, because a bug in it does not block the overall operation of the system (a problem that they can generate all the other blocks), in the worst case We face a monitor on, which has trace on the screen, but growing video information.
To diagnose the stage. Just use a oscilloscope faith to make a crawl from the entrance of the video card to output amplifiers color, the goal is to ensure that the signal suffers no defects or lost at any given time.
Kinescope .
We left the final appearance of screen, with the understanding that it is considered failure in this device, for example, a magnetized shadow mask, purity and convergence errors, failure to focus, etc. And given that these problems can be eliminated by methods already known to all electronic service technician, not expand on the subject. If you find a defective picture tube, it is best to suggest to the customer buy a new monitor, the reason is that as these devices are highly accurate, are generally not well when they are "repaired" (plus the cost of a new picture tube is almost equal to that of a new monitor).
As you can see, the steps for troubleshooting on monitors is well structured, ranging from those blocks that directly affect the overall operation of the system to others who may presentarfallas hardly noticeable.
We recommend you practice on various makes and models of monitors, and you will see that all the steps are the same.
And do not forget to apply the hypothetical-deductive!
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