d4mn bad ch1

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i got a bad lm4065 for free in hopes i could fix it cause it didnt turn on.
so i take the cover off and i can see the remote trace is broken so i jump the points and it turns on. i go through testing channels.

all but 1 works and i cant find any bad traces or burned components.

does anyon e have a schmatic of this amp or anything?

ill try to snap some good pics.
 
i found one bad part on the amp. an RFP70N06-ND MOSFET N-CH 60V 70A TO-220AB. it is cracked and is messed up. (i powered it up and noticed the crack i touched it and it sparked) the odd thing one side of the amp had those transistors and the others have an different type.

someone has worked on the amp before(some one has changed one of the opamps cause it has a different gasket underneath it)

im going to try and replace that transistor and see if that does it.
 
inside1.jpg

the one circled in blue is the broken one
the ones in green are RFP70N06-ND
and the ones in red are
Untitled-1-1.jpg


the one in blue is cracked and messed up. nothing else looks burned or broken.
 
Did you have a question?

If one of the RFP70N06s are blown, you need to replace both of them.

I don't have a schematic but you shouldn't need one.

It appears that at least one of the gate resistors (near the 70N06s) overheated. You need to check it after removing the FETs. It also appears that the FETs are driven directly by the PWM IC (SG3525?). If that's the case, the IC may have been damaged also.

What are the numbers on the power op-amps?
 
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