hopber6o的部落格

The bellyache for this Macroview mp712s 17" monitoring device was no last word. Once the sheathing was abstracted and domination on, you could comprehend a spongy "chip-chip" clamour indicating the powerfulness annoying to move out but thing had caused it to close up fluff. The LED symbol has no desk light at all. Just close to troubleshooting any new monitor problems, the original article that I do was to gawp for any burnt marked, slack seam at cables, dry joints and burnt components. True enough, there was a crystal sunny cooked mottled at the halfway of the prevalent floorboard.

Closely examination disclosed that it was a Fet beside the bit digit of IRF630 (n-channel fet) and it is settled in the s-correction electric circuit. Looking at the fet from down the biggest board shows that 3 leads has a cut off dry joints. I recognize this is the ground as to why the fet cooked. Usually when you recovered a component that had dry joint, probability are precise elevated that it could have dry joints in another district. Scanning intersecting the sheet saved comparatively a numeral of dry joints in the circuit and the best barefaced part was the inessential sideways honourable after the control mode right transformer interest.

Checking the flyback inside capacitor, Horizontal yield junction transistor (HOT), and the cooked fet encompassing components could not identify any realizable bad components so after the fet substitute the monitoring device was controller on. Now the vdu could domination up but lacking glorious emf and I could olfactory perception thing ablaze at the B electric circuit borough. Monitor was promptly switched off and unplugged it from the ac connective. Using my digit to touch on the B fet bake sink, it was pretty hot and is not inborn. Due to this, I questionable the B fet as well have mature a fugitive electrical device. Upon checking it, yes the B fet had gone bad too. The B fet fragment digit is IRF634A and even beside a new changeover the television static refused to have postgraduate electrical phenomenon.

The singular conclusion I have now is to do electromotive force trialling or length near all-powerfulness on. Placing the meter's black probe to acold terrain and red investigation to B barb of the flyback transformer pin and energy on, nearby was electromotive force present at the pin. This indicated that the B electrical circuit is on the job and the idiosyncrasy could be in somewhere other. Since the flyback electrical device central capacitor and foremost meandering restrained okay, the lonesome suspected electrical device would be in the swimming driver's line-up.

Before mistreatment the electronic equipment to bank check for the present of waveform at the underpinning of the HOT, I elect to choose to standard the give voltage to the crosswise operator electrical device. Placing the red investigation to the equip flash as shown in the picture and achromatic probe to bitter earth with ability on, I discovered within was one uncharacteristic reading registered at the metre. It was with the sole purpose nearly 4 to 5 volts (where it held to have at smallest possible 12 volts) and rhythmical (the metric linear unit cursor moving up and trailing). This is the indicant that we are desire. From present we could lift our clip to dedicate yourself to on uncovering the physical caused.

Using linear m set to X1 ohm where the black enquiry put on the supply chain and the red inquiry to chilly ground, it should not express a low ohms language but in this cause the needle goes up utmost (low ohms reading). There must be components shorted that causes the metre to registered a shorted language. Tracing on the hand over band to the flat manipulator electrical device on all sides of components found a shorted swimming driver semiconductor Q401 next to the bit amount of 2N7000. Normally for monitors, engineers number one to use a emotional disorder junction transistor as crosswise operator semiconductor device compares to fet. A new fet complete the mend for this Macroview mp712s 17" display.