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Repair / Help Forum => Repair / Help => Topic started by: Falcon on December 28, 2009, 11:45:23 PM

Title: Output transistors?
Post by: Falcon on December 28, 2009, 11:45:23 PM

I just replaced a set of outputs on a Denon amp (2) 2sa1491 and  (2) 2sc3855. I have done these before with no problems, As soon as I hit the power button it blows a fuse.. ??? ???. I double checked all the solder joints and everything, I know how to do it, new heat-sink compound, everything.  Any ideas, I wonder if by buying the cheap ones, I got counterfeit's. I bought them from electronix.com. Anyone ever buy from them?

 Anyhow, any ideas? I know it was bad outputs, they would distort in the left channel after being on for 5 minutes. Everything else tested good.

Title: Re: Output transistors?
Post by: OCCD on December 31, 2009, 11:31:29 PM

I will see if I have some stashed away. if I do, I will test them first.

Title: Re: Output transistors?
Post by: Falcon on January 01, 2010, 01:25:08 AM

Thank you Tom.
  I am sure I got shit ones from electronix.com I will never buy parts from them again... I put the old ones back in and the amp works, like it did before with a distorted channel. So it is obvious the new outputs do not work. I seen a bit on Audio karma someone else getting counterfeit transistors from them, so look elsewhere to buy parts.

Mike