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Onkyo HT-R490 sound problem

 
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joser



Joined: 09 Jul 2010
Posts: 1

PostPosted: Fri Jul 09, 2010 3:02 pm    Post subject: Onkyo HT-R490 sound problem Reply with quote

my 10yrs old receiver Sad

It will produce a sound for a couple of minutes and cut off
when I turn off and turn on again the sound back for a couple of minutes.

I opened the cover and found out a pcb burn marks near D935, D936 and R924 near white ribbon connector/terminal

any ideas?

thanks
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Pentode



Joined: 30 Oct 2007
Posts: 85
Location: Nr. Manchester (UK)

PostPosted: Tue Jul 13, 2010 6:58 pm    Post subject: Reply with quote

From time to time we do see burn marks under components that run rather warm... what could have happened is that the heat could have damaged the soldered connection underneath, we call these 'dry joints', they look dull, gray and tired, close inspection may reveal cracks around component leads and all that's required here is a re-solder.

On the other hand it could be caused by a faulty component, usually a regulator, transistor, chip (IC) or diode that has gone leaky.

A check with a test meter should reveal further clues along with a re-solder.

Dave
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