Below are the 2 most recent journal entries recorded in randythompson23's InsaneJournal:

Monday, January 16th, 2012
10:29 pm	LCD Monitor Problems - Good way to Repair It Today's article discusses repairing the CMV 19" LCD Monitor problems model CM-922D. The complain was no power as what the customer explained. This power supply was not included in the circuit thus it need an external power adapter to power up. The input towards the LCD Monitor is 19V with 3.1 Amp from the adapter. Because the complain was no power, we have to test drive it to check if the ability adapter reaches fault or even the LCD Monitor. The ac supply was plugged in to the power adapter and that i could see the ability LED was lighted up. Checking the output voltage of the power adapter I acquired about 19 volts that is good. Although the LED has lit and proper output voltage, it doesn't imply that the ability adapter can maintain when there is a load (the LCD Monitor) attached to it. I remember when i discovered a Compaq 17" LCD Monitor that have an exact output voltage from the power adapter however when connected to the Monitor, the display appeared for any fraction of the second before shutting down. Usually in this case, your experienced would tell you that it may be the inverter circuit are faulty or even the lamps have problem. You'd be surprised the actual reason for the shutdown was due to the power adapter. It cannot sustain the output voltage if you find a lot onto it. This kind of fault was normally as a result of bad filter capacitors located in the creation of the secondary circuit. If you have ESR meter, it is possible to locate the defective electrolytic capacitors fast. Without having the meter, just direct replace the caps. As mentioned in my previous repair articles, to verify when the power adapter is really working or otherwise you'll need a lamp to act like a load. Ensure the power LED light doesn't blink whenever the light bulb is connected. Even if it blinks once, this proves that the regulation is not good and want to be check entirely. Within the above china made LCD Monitor, the power adapter work perfectly fine! Since i have have previously confirmed the power adapter is nice, my focus now was around the LCD boards. Removing this cover was super easy and you will easily access to the board once the metal casing was removed. The first thing that I checked was the SMD fuse located in the main board. If the fuse opens then there would be no supply towards the ADC/SCALAR and also the CPU IC thus the power LED would not light! Checking this SMD fuse was rather simple because the method of checking it is the same like a normal fuse. Use either an analog or perhaps a digital meter set to ohms range or continuity check. You can check the fuse while it is still in circuit. Yes, the fuse was discovered to be open circuit. lcd monitor repair Now there is one question that should be answered by us. Why is the fuse to visit open circuit? Well from what we have known about electronic repair, you will find three possibilities as why a fuse opens circuit. First, the fuse may become open circuit because of its lifespan. Some fuses can last for a long time although some only few years. Quite simply, living of the fuse depends on the qualities from the materials used. Secondly, the external factor such as a surge causing the fuse to open circuit to be able to protect the main board. Thirdly, the main board itself have problem (like a shorted IC's and other electronic components) that caused the fuse to open circuit. If the LCD Monitor problems falls within the first and also the second categories then replacing only the fuse will definitely solve the problem. However, with this LCD Monitor, replacing just the fuse failed whatsoever and also the fuse open circuit again. You've only two choices to solve this kind of problem. Firstly you may use an external regulated power supply as explained during my previous repair articles and fasten the negative output of the ability supply to ground and also the positive towards the fuse (the road that leads to other circuitry) to be able to detect the short circuit. Slowly vary the output voltage and monitor the present drawn. When the current drawn in regards to a amp or two, now place your finger to any electronic components in the primary board. If you found any components that get hot then that's the cause of the short circuit. In this article, I'm going to do it differently to detect the short circuit. Are you ready? Now instead of replacing the fuse with the exact rating that is 3 amperes, I replaced it with a 5 amperes fuse. The reason that i can place the 5 amp fuse instead of the 3 amp fuse was because "if the fuse doesn't blow then the component that have short circuit would blow". Do you obtain the idea? Three things sometimes happens if you use this way to force out the culprit. First the ability adapter may shut down due to heavy current draw from the primary board. Second, the short circuit electronic components (either be a IC, diode, capacitors, transistor and etc) will get hot and you can quickly locate it easily by touching them. Remember don't onto it for too long otherwise when the shorted components get too hot it'll go open circuit and now you may have a hard time to discover the fault. Third, you may hear a pop sound and spark in the shorted component. Trace from where the spark came from and you can easily identify the place and sometimes towards the actual component that create the spark. laptop screen repair For that above LCD Monitor, I personally saw a little spark at the top part of the main board when the power input jack was connected. It prompted me towards the exact place and when I check the SMD ceramic capacitor (that generated the spark beneath it) with analog meter set to X 10 K ohm range; it really developed a slight short circuit. Replacing just the fuse and also the SMD ceramic capacitor solved no power condition in this 19" LCD Monitor. This Monitor uses the inverter IC (OZ960G), A1084-25CM (2.5 volts voltage regulator), AMC1117-3.3 (3.3 volts voltage regulator), ADC IC (MST8136B) and CPU IC (MYSON MTV312MV64). Conclusion-There are always options regarding which methods that you would like to make use of to detect the short circuit. Should you prefer the latter one, then I suggest you to try taking some photo shots first before anything really burnt out beyond description. With the photos, at least you'll have some hints of the items the components may be or even the part numbers. Well, there's always a fascinating way to solve electronic problems and this is among the reason that I like electronic repair a lot since you can always act as a detective to discover the culprit-real satisfaction! Oh! By the way, you can use the above mentioned approach to any other electronics which is not limited simply to problems repair. Have a great hunt my friend! (Comment on this)
10:25 pm	LCD Monitor Problems - Easy Way To Repair It Today's article discusses repairing the CMV 19" LCD Monitor problems model CM-922D. The complain was no power as exactly what the customer explained. This power supply wasn't built into the circuit thus it need an external power adapter to power up. The input to the LCD Monitor is 19V with 3.1 Amp from the adapter. Since the complain wasn't any power, we must test drive it out to see if the ability adapter reaches fault or even the LCD Monitor. The ac supply was plugged in to the power adapter and that i often see the ability LED was lighted up. Checking the output voltage of the power adapter I got about 19 volts that is good. Although the LED has lit and correct output voltage, it doesn't imply that the power adapter can maintain if you find a load (the LCD Monitor) attached to it. I remember when i discovered a Compaq 17" LCD Monitor which have a precise output voltage from the power adapter but when connected to the Monitor, the display appeared for a fraction of a second before closing. Usually in this instance, your experienced would tell you just how it may be the inverter circuit are faulty or even the lamps have problem. You would be surprised that the actual reason for the shutdown was due to the power adapter. It cannot sustain the output voltage if you find a load onto it. This sort of fault was normally as a result of bad filter capacitors located at the creation of the secondary circuit. If you have ESR meter, you can actually locate the defective electrolytic capacitors fast. Without having the meter, just direct replace the caps. As stated in my previous repair articles, to verify if the power adapter is really working or not you need a lamp to act like a load. Ensure the power LED light doesn't blink whenever the sunshine bulb is connected. Even when it blinks one time, this proves the regulation isn't good and need to become check entirely. In the above china made LCD Monitor, the power adapter work perfectly fine! Since i have have previously confirmed the power adapter is good, my focus now was around the LCD boards. Removing this cover was very easy and you can easily access to the board once the metal casing was removed. First of all , I checked was the SMD fuse located in the main board. If the fuse opens then there would be no supply towards the ADC/SCALAR and also the CPU IC thus the ability LED wouldn't light! Checking this SMD fuse was relatively easy as the approach to checking it's the same like a normal fuse. Use either an analog or perhaps a digital meter set to ohms range or continuity check. You should check the fuse even though it is still in circuit. Yes, the fuse was discovered to become open circuit. lcd monitor repair There is one question that needs to be answered by us. Why is the fuse to go open circuit? Well from what we have known about electronic repair, you will find three possibilities as why a fuse opens circuit. First, the fuse may become open circuit because of its lifespan. Some fuses may last for a long time although some only couple of years. Quite simply, living of a fuse depends upon the qualities of the materials used. Secondly, the external factor such as a surge causing the fuse to spread out circuit in order to protect the primary board. Thirdly, the main board itself have problem (like a shorted IC's along with other electronic components) that caused the fuse to spread out circuit. When the LCD Monitor problems falls within the first and also the second categories then replacing just the fuse will definitely solve the problem. However, for this LCD Monitor, replacing only the fuse didn't work at all and also the fuse open circuit again. You've only two choices to solve this kind of problem. First you may use another regulated power supply as explained in my previous repair articles and connect the negative output of the ability supply to ground and also the positive to the fuse (the line leading to other circuitry) to be able to detect the short circuit. Slowly vary the output voltage and monitor the current drawn. When the current drawn in regards to a amp or two, now place your finger to the electronic components in the main board. Should you found any components that will get hot then that's the cause of the short circuit. In the following paragraphs, I'm going to get it done differently to detect the short circuit. Isn't it time? Now instead of replacing the fuse with the exact rating that is 3 amperes, I replaced it with a 5 amperes fuse. The purpose that i can put the 5 amp fuse instead of the 3 amp fuse was because "if the fuse doesn't blow then the component that have short circuit would blow". Would you obtain the idea? Three things can happen if you use by doing this to force the culprit. First the power adapter may turn off because of heavy current draw from the main board. Second, the short circuit electronic components (either be a IC, diode, capacitors, transistor and etc) can get hot and you can quickly locate it easily by touching them. Remember don't on it for too much time otherwise if the shorted components get too hot it'll go open circuit and you may have difficulty to discover the fault. Third, you may hear a pop sound and spark in the shorted component. Trace where the spark originated from and you will easily identify the place and sometimes towards the actual component that generate the spark. laptop screen repair For that above LCD Monitor, I personally saw a little spark at the top part of the main board once the power input jack was connected. It prompted me to the exact location and when I look into the SMD ceramic capacitor (that generated the spark underneath it) with analog meter set to X 10 K ohm range; it really created a slight short circuit. Replacing just the fuse and the SMD ceramic capacitor solved the no power problem in this 19" LCD Monitor. This Monitor uses the inverter IC (OZ960G), A1084-25CM (2.5 volts voltage regulator), AMC1117-3.3 (3.3 volts voltage regulator), ADC IC (MST8136B) and CPU IC (MYSON MTV312MV64). Conclusion-There are always options regarding which methods that you would like to make use of to detect the short circuit. Should you prefer the latter one, then I suggest you to definitely take some photo shots first before anything really burnt out beyond description. Using the photos, a minimum of it will give you some hints of what the components may be or even the part numbers. Well, almost always there is a fascinating way to solve electronic problems which is one of the reason that I like electronic repair a lot because you can always act as a detective to find out the culprit-real satisfaction! Oh! Incidentally, you should use the above mentioned method to every other electronics which is not limited simply to problems repair. Have a great hunt my friend! (Comment on this)