Ok, does anyone have a good source for how I should be testing these particular mosfets? Ive viewed a few videos on youtube, but just looking for suggestions.....
Thanks!
If they don't check shorted, they are very likely ok. For a proper test you need to remove them and that could just cause more problems.
Ok, so I removed the heatsink that attaches to the two mosfets, I understand this is probably overkill but I wanted to be as throrough as possible. Please see the attached picture with both of the mosfets, I believe thy are MDF18N50, also see the attached link with the data sheet for reference....
I am still struggling in testing out these two mosfets, Im unable to re-create the testing results using 3 different multimeters I have with diode mode......Im not sure if Im doing something wrong or if there's something specific about these components that would prevent me from using a standard inexpensive multimeter in diode mode to test......any help is much appreciated......
I am still struggling in testing out these two mosfets, Im unable to re-create the testing results using 3 different multimeters I have with diode mode......Im not sure if Im doing something wrong or if there's something specific about these components that would prevent me from using a standard inexpensive multimeter in diode mode to test......any help is much appreciated......
I kind of thought about that, even though I was not sure.....is it because my meter is powered with a 9v battery it doesnt have enough voltage to trigger the mosfet to turn on/off? I know that description is pretty crude/simple, just trying to understand the concepts.....If that's the case Im guessing i'd need a more powerful DMM or a bench type meter that plugs into the wall? Regardless, Im purchasing one of those cheap LCR tester meters on amazon to try and sort things out.....
I replaced the cap as well as resoldering the heatsink and mosfets. I was too impatient to wait for the LCR meter to arrive. TV seems to power up normally!!! Great news. Thanks to all for the help and advice.
thetonywarren do you happen to have any high resolution photos of the back of the power supply board? My TV recently stopped working and I was able to find some components that were blown related to the 24V main supply. I was able to replace QW401 and R404, but there is a small resistor on the back side (R402) that is part of the gate drive circuit that has a hole blown right through the part marking. Hoping I can find the resistor size in a high resolution image.
Any help you can provide would be appreciated, thanks in advance!
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