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The bellyache for this Macroview mp712s 17" monitoring device was no potency. Once the case was separate and pressure on, you could comprehend a cottony "chip-chip" stable indicating the impetus testing to move out but something had caused it to closed downfield. The LED symbol has no neutral at all. Just approaching troubleshooting any opposite monitoring device problems, the archetypical entity that I do was to look for any cooked marked, free tie at cables, dry joints and burned components. True enough, within was a solid explicit burnt tarnished at the central of the prevalent flat timber.

Closely examination revealed that it was a Fet next to the section amount of IRF630 (n-channel fet) and it is situated in the s-correction electrical device. Looking at the fet from at the rear the prevalent commission shows that 3 leads has a severed dry joints. I believe this is the foundation as to why the fet burned. Usually when you found a constituent that had dry joint, likelihood are highly superior that it could have dry joints in different speciality. Scanning cross-town the flat timber recovered rather a digit of dry joints in the electrical device and the most plain sector was the minor sideways retributive after the controller manner energy electrical device constituency.

Checking the flyback inside capacitor, Horizontal production semiconductor unit (HOT), and the burned fet encircling components could not pin down any possible bad components so after the fet standby the display was electric switch on. Now the vdu could propulsion up but short overflowing electrical phenomenon and I could trace something sizzling at the B electrical circuit district. Monitor was promptly switched off and unplugged it from the ac instrumentality. Using my digit to touch on the B fet energy sink, it was slightly hot and is not ordinary. Due to this, I queer the B fet as well have formulated a thick electrical device. Upon checking it, yes the B fet had gone bad too. The B fet section digit is IRF634A and even near a new transposition the display immobile refused to have utmost voltage.

The lone assessment I have now is to do voltage trialling or measuring with influence on. Placing the meter's achromatic probe to bleak terra firma and red investigation to B tine of the flyback transformer pin and authority on, nearby was electrical phenomenon existing at the pin. This indicated that the B electrical circuit is exploitable and the bad habit could be in somewhere else. Since the flyback electrical device interior capacitor and foremost roundabout curbed okay, the single suspected electric circuit would be in the horizontal driver's cross.

Before mistreatment the cro to draft for the instant of wave shape at the podium of the HOT, I select to consider the endow emf to the horizontal manipulator electrical device. Placing the red enquiry to the provide chain as shown in the image and black research to unheated broken next to momentum on, I observed there was some unusual language registered at the metre. It was one and only about 4 to 5 volts (where it designed to have at lowest possible 12 volts) and rhythmical (the meter mark blown up and set). This is the indication that we are want. From here we could lug our juncture to tincture on discovery the physical caused.

Using linear metric linear unit set to X1 ohm wherever the black investigation put on the supply procession and the red probe to frosty ground, it should not ascertain a low ohms linguistic process but in this suit the indicator goes up overflowing (low ohms linguistic process). There must be components shorted that causes the metre to registered a shorted linguistic process. Tracing on the provide dash to the naiant manipulator electrical device close components saved a shorted flat operator junction transistor Q401 with the portion numeral of 2N7000. Normally for monitors, engineers preferred to use a major affective disorder junction transistor as swimming operator semiconductor device compares to fet. A new fet completed the fix for this Macroview mp712s 17" computer screen.