How to repair a dead dvd power supply

Let's consider how to repair a dead dvd power supply and an example of a type of dvd supply is shown above sourced from electronicsrepairguide.com.what will be observed is the fuse may have get blown.I will advise you don't change the fuse immediately because doing so without first of all checking for defective component in the circuit can wreck a great havoc in the supply.What you need to do before replacing the fuse is to range your multimeter to x1 ohms range and take readings at the terminals of the power capacitor.If your readings tends towards zero in both direction that means some components are defective so it is better you check and replace them before the fuse will be replaced.One common problem that is related to this supply always has to do with the control ic. when it short circuit-due to high voltage or power surge-it will blow the fuse,so you can source for a replacement at an elctronics spares shop.The bridge rectifier diodes also can be a problem ,take readings of these diodes so as to be sure they are in good condition.If after all these you take readings at the terminals of the power capacitor and it reads short circuit again, definitetly  the capacitor will need to be replaced to correct the fault and  put the supply in good working condition.All this while what I've been talking about deals with the primary side of  the sm transformer.In the next post I will discuss faults related to the secondary side.    

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