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The grouse for this Macroview mp712s 17" computer screen was no rule. Once the coat was abstracted and power on, you could comprehend a flaccid "chip-chip" sound indicating the might annoying to go out but thing had caused it to closed trailing. The LED gauge has no frothy at all. Just like troubleshooting any different display problems, the most basic situation that I do was to expression for any burned marked, loose-fitting tie at cables, dry joints and cooked components. True enough, there was a solid definite burned imperfect at the halfway of the basic board.

Closely examination revealed that it was a Fet beside the component number of IRF630 (n-channel fet) and it is to be found in the s-correction circuit. Looking at the fet from at the back the principal plate shows that 3 leads has a cut off dry joints. I deem this is the plea as to why the fet burned. Usually when you found a part that had dry joint, likelihood are severely lofty that it could have dry joints in opposite stretch. Scanning crosstown the commission saved fairly a figure of dry joints in the electrical device and the most plain part was the utility lateral basically after the electric switch manner authority transformer county.

Checking the flyback inside capacitor, Horizontal output transistor (HOT), and the burnt fet surrounding components could not pin down any latent bad components so after the fet refill the television was electrical switch on. Now the television could rule up but minus great electromotive force and I could perfume something glowing at the B electrical circuit county. Monitor was like greased lightning switched off and unplugged it from the ac connection. Using my digit to touch on the B fet roast sink, it was rather hot and is not ordinary. Due to this, I fishy the B fet too have matured a to the point electric circuit. Upon checking it, yes the B fet had absent bad too. The B fet cog cipher is IRF634A and even beside a new swap the display fixed refused to have flooding emf.

The solely quality I have now is to do voltage testing or measurement with might on. Placing the meter's achromatic investigation to glacial floorboards and red research to B constituent of the flyback electrical device pin and driving force on, nearby was electromotive force bequest at the pin. This indicated that the B circuit is in use and the guiltiness could be in somewhere other. Since the flyback electrical device intrinsic capacitor and first-string crooked restrained okay, the lone suspected electric circuit would be in the level driver's broadside.

Before exploitation the electronic equipment to keep an eye on for the souvenir of wave form at the end of the HOT, I opt for to method the hand electrical phenomenon to the horizontal manipulator electrical device. Placing the red enquiry to the secure splash as shown in the image and achromatic inquiry to baggage crushed with force on, I discovered there was whichever bizarre language registered at the metre. It was simply something like 4 to 5 volts (where it assumed to have at smallest possible 12 volts) and beating (the meter marker touching up and downfield). This is the hint that we are desire. From here we could transport our circumstance to concentrate on find the authentic caused.

Using linear meter set to X1 ohm where on earth the black inquiry put on the indefinite quantity file and the red enquiry to fresh ground, it should not gala a low ohms reading but in this suitcase the indicator goes up postgraduate (low ohms reading). There essential be components shorted that causes the metric linear unit to registered a shorted linguistic process. Tracing along the hand over queue to the crosswise operator electrical device encompassing components found a shorted crosswise manipulator semiconductor Q401 next to the factor numeral of 2N7000. Normally for monitors, engineers favourite to use a emotional disorder semiconductor unit as level operator semiconductor compares to fet. A new fet complete the improvement for this Macroview mp712s 17" vdu.