can you help me fix this psu?

[newtoCaps101]

guys, I have this power brick from a cheap hard drive enclosure that has stopped working, its out of warranty period so I opened the power pack and found some burns. pretty cheapish design but i was thinking if i could maybe fix it instead of buying a new adapter for $10 + shipping.

here' some pics i got, seems to be the 3 legged mosfet that's connected to the heatsink.

[tom66]

Re: can you help me fix this psu?

Do you have any pictures of the top side of the board?

[newtoCaps101]

Re: can you help me fix this psu?

heres a few,
(the big 22uF 400V cap had a discolored tape on top of it, the cap itself is fine not leaking).

[mariushm]

Re: can you help me fix this psu?

Well, that transistor is probably dead... replacement one is about 2$ plus shipping.... which might get you to the same 8-10$ :

http://www.findchips.com/avail?part=4N60

i think this one is compatible http://search.digikey.com/scripts/Dk...&mpart=AOT4N60

But you have to check the diodes and the resistors around and make sure they're not also dead.

How is that power supply even generating the 5v and 12v? Seems to me like it's plain and simple diodes rectifying and sending the voltage directly from transformer to the capacitors and then down the wires. Wouldn't trust that thing to give power to my hard drives

[newtoCaps101]

Re: can you help me fix this psu?

one of the resistors looks to be fried. repair cost might set me back around $5 - $10 and even then it wont be a good product.
maybe I should spend the $20 - $30 and buy a proper enclosure altogether?

[tom66]

Re: can you help me fix this psu?

No EMI filter, three transistor discrete oscillator... That's an unregulated power supply. Could easily send a voltage that's too high to your HDD.