Immediately after eliminating the B+ fet, not merely the facility didnt blink, there was screen also and the anode voltage reads about 12 Kilo volt (a very good monitor ought to have about 24 KV). The main reason why you got 12 kilo volts is because the boost circuit is not operating a result of the removal of the B+ fet. The show shown a small width as well as the horizontal dimension command is previously set to the optimum (you cant get utmost width as the anode voltage is just twelve KV). You are able to regulate or established anything while in the On Display screen Show (OSD) except you cant bring horizontal sizing to utmost.
Capacitor regularly gets to be an unsung hero of electrical circuits which storing probable voltage for staying launched on demand, pretty much similar with a battery. Capacitor is normally neglected until finally the 1 goes bad which may lead to an entire machine to are unsuccessful or malfunction. Digital voltmeter, that's often called a multimeter is quite practical to test if the capacitor is keeping a demand. You are able to do this method very easily and immediately. At this time, this post goes to provide you with some clever tricks to take a look at a capacitor with a voltmeter.
Ordinarily soon after electrical power off, I might contact around the flyback very first then to other parts encompassing the higher voltage portion. While browsing the elements with my finger I stumbled upon a resin coated ceramic disc capacitor that's rather incredibly hot. It's found near the flyback transformer as well as in simple fact the capacitor was there's to act as a filter capacitor to the 400 vdc line output as demonstrated in the photograph.
Commonly what I do is to eliminate the B+ fet initially and link a lightweight bulb to tell apart no matter if will be the primary or just after the B+ circuit components that induced electrical power to blink. Having said that in this instance, I didn't set the light bulb and i instantly removed the B+ fet and ability over the keep an eye on. For your information, this B+ fet will be the Nchannel mosfet which B+ fet is part of the raise circuit.
To begin with make not of what basically takes place after you force the ability button as you could conserve your self aquiring a personal computer repair. Does one hear the followers whirring inside prior to it shuts off, will it not come on in any way, are there any beeps and so on?
Future, checking all around all the circuit, I found an additional electrolytic capacitor have issue much too. The faulty capacitor is located at the secondary output side and act as a filter to eliminate ripple together the output line. A very good a thousand uf ecap must have ESR fewer than .one Ohm but the faulty one examine four.nine ESR Ohm! A brand new substitution of your Pico fuse, C5707 transistor, FQU11P06 FET, 1000uf 16Volts ecap and .22uf 250V metallised polyester capacitor introduced the Liquid crystal display Monitor back again to daily life once again.
The last move that you choose to need to to is always to test the outcomes by using a regarded operating capacitor of the very similar sort in the approach to make up for just about any anomaly with all the meter. So, by following some strategies above, now you could very easily exam the capacitor having a voltmeter.
The moment the metallic casing was taken out, I could clearly see a burnt mark surrounding a transistor situated at the inverter board place. My assumption was appropriate concerning the inverter circuit fault and upon shut inspection; the slightly dim transistor has the portion range of FQU11P06. It is just a Pchannel FET transistor and it can be replaced with element range FU9024N. The realm now has darkened and when you straight set up a whole new transistor in it, I feel the darkened area could result in intermittent difficulty or overall destruction all over again to the new transistor! Why? It truly is because the darkened spot is now carbonized and present can move to other circuits creating the transistor to go shorted once more. To be able to eliminate this problem, 1 needs to scrap off the darkened spot and a result of the board is so fragile; the only way you can do should be to make 1 hole inside the area. Clean up the area with thinner and set up the brand new transistor and it should really not have trouble following that.
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