| 30bandgeek |
Hey i have 8004 4 channel fosgate, it turns on, two channels dont work, the other tow channels is putting out like 70v dc or something, it just fryes any speaker instantly as soon as a speaker gets hooked up.
I opened amp and there is nothing visabally worng with it.
I used to build pcb fabs and programming on SMT equipment so i am comfortale with soldering, id ing parts and stuff. But there is nothing visabaly fryed,
any suggestions to help kick me in the right direction or any ideas on what i could test?
thanks in advance
Adrian |
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| Perry Babin |
If the outputs have shorted, that could be the cause of the high voltage on the outputs. That amp shouldn't have 70 volts of rail. I'd expect something closer to 40 volts.
Check:
The output transistors
The 0.1 ohm source resistors
The driver transistors (Qx19-Qx22)
The 20 ohm SMD resistors connected to the emitters of the driver transistors
If any of the 0.1 ohm resistors have failed, you may also have some damage to the protection circuit. You would need to check the 15 and 39 ohm SMD resistors connected across the source resistors.
Let us know what you find. |
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| 30bandgeek |
yeah it is accualy around 40V so you are right about that..i exagerated a bit. I guess i shouldnt do that when ask8ing for help...sry...mybad
but i will check those things out and let you know what i find. |
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