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 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.    

How to troubleshoot dead power supply with ease.

Power faults remains one of the most common faults when it comes  to electronics.It may be due to power surge from ac supply ,high voltage or when a component fails at the power stage.What will be noticed is that the fuse will get blown and the mistake we normally make- especially beginners in the field of repairs- is to just change the fuse and power the set.This may result to greater damage of the power supply so it is better to check other components in the supply before deciding to replace the fuse only.Usually when there is a short circuit there is bound to be problem,you need to check for short circuit at rectifier diodes or power capacitor which are the major causes of  blown fuse.In this series I will be examining different power supplies and how you can troubleshoot them.

Akira TV fails to raster with standby light on

A friend of mine brought an Akira 14'' colour tv for repair with the above mention fault.Atimes it will take 30-40mins before the raster comes on and after about 4mins it will fade away with the standby light still on.
       I discovered dry joints on the panel board and resoldered it.The raster came on immediately I switch it on but fade away again within 5mins.This fault  always connect with the video board so I also check for dry joints and resolder it but the problem persisted.That is it with repair,you need to have a persistence spirit to be a good repairer and if you have professionals around it will hasten up your learning.There is hardly any fault you may encounter on your repair work that someone somewhere hasn't pass through and sharing it with them will help a lot.
Back to what we are treating,I checked +180v supply to video board,it was there.I hold on to the board tightly and noticed the raster came on and fade away as I leave it.This is a sign that the tube base is having problem.As the tube base was replaced with a new one the fault was cleared and  the raster came on for more than an hour without fading away.