its a Marshall MG100DFX and my friend plugged it into his 4x12 cabinet (im not sure the impedance or the wattage) when i wasnt there and he fried it i guess. He said is started smoking and so he turned it off. then he turned it back on and the fuse blew. so he replaced the fuse and turned it back on and it blew again. I think he tried turning it on without a speaker plugged in as well, not sure if he did it before or after the fuse blew. I opened it up and looked around and found that this transistor was cracked, melted around the crack, and had smoke residue on it. Everything else inside the amp looks in perfect condition so im assuming everything else is ok. I ordered a couple of those transistors and i have already desoldered the old chip off (below)
that transistor was screwed against a black heatsink which has a 50mm fan on it. (top left corner below)
I'm not really sure what im doing or what is wrong with the amp. It is obvious that the fried transistor needs replacing, but what would be the next thing to fry or get messed up in some way after that chip fries, or can i be certain that the fuse blew before anything else fried?
that transistor was screwed against a black heatsink which has a 50mm fan on it. (top left corner below)
I'm not really sure what im doing or what is wrong with the amp. It is obvious that the fried transistor needs replacing, but what would be the next thing to fry or get messed up in some way after that chip fries, or can i be certain that the fuse blew before anything else fried?
I'm not sure if your amp is fried, or repairable- seems like you're doing what needs to be done...just replace that transistor, MAKE SURE everything goes back together all proper-like, and take extra precautions not to "bleed" your solder joints into eachother, or you're just asking for a refry. After it's all back together, plug 'er in and watch the fireworks! You should be all set, if not, it's off to the repair shop dude! Good Luck~!
