Hello guys and girls,

I have a rather expensive active subwoofer, which stopped working a few days ago.

I opened it up and found that a resistor was burned on the DSP preamplifier board.

Since this board also enables the end-amplifier and configures the sound, i need it for the thing to work.

I can solder in a new resistor, if only i knew what properties it should have.

Can anyone tell me the values of the resistor in the picture?

Thank you so much for helping me out.

Grtz.

 

When resistors burn, it's usually caused by a fault elsewhere.

Sorry I can't identify the resistor.

 

.. Take a better picture of U400, on the heat sink. Maybe there will be some visible sign of heat stress.

 

.. Take a better picture of U400, on the heat sink. Maybe there will be some visible sign of heat stress.

Thank you for your reply.

They look pretty good, as far as i can see.
I put U1 on here too.

 

Here are some pictures made with flash.

 

There is some sort of black spot at the base of the heat sinked part, but it is difficult to say if it is due to overheating or merely a shadow. The U400 is a 3.3 volt voltage regulator and could be the root cause of the problem if it is defective.

 

There is some sort of black spot at the base of the heat sinked part, but it is difficult to say if it is due to overheating or merely a shadow. The U400 is a 3.3 volt voltage regulator and could be the root cause of the problem if it is defective.

What you see is some green loctite kind of stuff.

The weird thing is, on side of the resistor is connected to the input-side of the LM1117 and the other side is connected to the input side of the L7812cv.

Any clues on the resistor value?
The colorcodes seem off. There is no black tolorance band.

 

... Take a close look at the other side of the board. Look for burned, oxidized,or melted out solder pins.