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I baught an amplifier kit from maplin. its a 200w power amplifier. the problem is now when i turn it the two of the resistor gets hot and they are 5W 0.47ohm resistor. can you please help me with this problem.

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Hi

Have you checked and set the bias current for the output stage. These 2 resistors will get hot if the bias is too high. Is it the firsy time you have fired the amp up? Operating in this condition may cause the output transistors to fail. If the output transistors are damaged,you would also experince heating of these resistors. Get back to me please and let me know if you have set bias

regards
robotek

Posted on Nov 08, 2008

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