Comment About My Previous Post
One of my repair friend responded about my previous post of having more meters in the repair bench. He encountered difficulty in identifying a components thus by using the Atlas peak analyzer, he managed to done the job. Let’s read about his comment:
Ya I am interested in all test meters, recently I bought atlas DCA component analyzer from peak electronic and it help a lot. One of my customer sent me a Panasonic TV which has no power, when I opened the case I really shock to see that all the board had been changed to China TV board by a technician without the owner’s knowledge which only can controlled by remote control and without channel selector preset.When I checked the board I found that the FET at power supply was shorted and the part marking was faded and can’t be seen, so I used my component analyzer to check it and it was a FET instead of normal transistor, changed it solved the no power problem.
Having more meters does not mean you have to use all the meters everyday in your troubleshooting job. But when you really need it to find out the culprit, that’s the time you will appreciate the most the metes you have bought. I don’t use oscilloscope everyday in my repair work but when i want to see the input and output waveforms i know that my faithful scope will do the job for me without putting much afford in locating the fault.
Dear Jestine Yong,
I’m reparing a 12v smps that blinks. it has a top225. I already replaced the top225 and checked all the esr capacitor and many components as well. but i do not find the problem. Could you give me some ideas to continue with it please?. The schematic is exactly the same as your article top224 schematic.
If you have checked all electronic components and could not locate any bad one then this mean it could be the components breakdown when under full load. I’ve repaired many CRT Monitors power supply blinks due to a diode located in the primary side have intermittent problem. Direct replacement solved the problem. In your case it could be different. Does this power supply use optoisolator ic? If yes, check the surrounding components and if posible direct replace the ic and retest again. A partial shorted of primary winding in the transformer also could cause power blink. Hope this helps!