mtx 6500d not 1 ohm stable

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I have read this thread in hopes of finding some useful information in repairing a 6500d that i put into a 1ohm load. The amp worked for about 30 secs then it just quit. I checked the 3 fues they were all blown. Keep in mind that the fuses were 15a. It calls for 25a. I put 3 new 25a and she started rollin again. I must say this amp is such a underated amp. I know its not a 1ohm stable amp but it lasted for about a week then one night boom it cut off and then i smelt it. I took the amp apart and imediatley noticed the input side mosfets were melted.

From the research i have done on this site i ordered some irf3205's to replace the 75339p.

I replaced them tonight and took some readings

FET601 climed to 900+
FET602 same
FET603 same
FET604 same

I got the readings with my DMM set to .OL and red probe on center pin and black probe on the right or left outer leg depending on which way your looking at it. If i reversed polarity i got the same reading but it was -984

Im afraid to power it back up due to maybe some other things i might need to look at like maybe R628 and R629 they look a little ruff compared to some of the others.

Last thing there are 2 fets labled REC601 and REC602. How should these read? Into the mega ohms like other fets?
 
Update!

I took the REC602 out of circuit and confirmed a reading of 0.000 in any configuration. It goes from .OL to 0.000 instantly while the REC 601 reads well into the 900's

The REC602 has U1620R CQ236 KAK on it

The REC601 has MUR1620C. N2 18 on it

Seems like same fet just different manufactors?

PS outta circuit means to desolder and remove from board? For testing purposes?? I got the same reading when the fet was on the board. Is this just to make sure its not being shorted out by something else
 
They broke in half. Hopefully i can scoop up some of them tomorrow along with some Rectifiers that i discussed in an eariler post.

I have a Little AC to DC converter that i can select voltage on from 3-12 volts. Can i use this to bench test? I put my meter on it and it read just as if i was checking the voltage off my car battery.
 
Thank you for the prompt responce as always. Soldering in these smb 0805s looks like it could get tricky. Any pointers? I will check out some youtube vids. When i mentioned i couldnt find the 0805s online i ment local. I stopped by today an he couldnt pull anything off of 0805s. Ill prolly just order from digi. All fets an rectifiers seems to be reAding into the mega omhs. Stupid ? But as i checked the power side it seemed as if the fets build off each other as i checked each one it just climbed and climbed.
 
To desolder the resistors, add new solder to both ends. Heat one end for a couple of seconds then move the iron quickly to the other side. When the solder melts, push the resistor off of the pads.

Desolder both pads with desoldering braid and add hew solder to one pad. Heat the solder on that pad and slide the new resistor into it. Then solder the other end.

The rectifiers are likely OK but to know definitively, you'd have to check them out of the circuit (no reason to do so at this point).
 
Well i'm not out of the woods yet. Keep in mind i never tried to put power to the amp since it poped. I went to hook up, but i didnt have power it seemed at least no red led power. seems like at this point without schematics or maybe a working mtx 6500 to use to get readings. Any schematics out there by chance???
 
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