Question about Audio Players & Recorders

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Thanks I am savy but can not find the service manual or schematics for this unit. If the output transistors have shorted to ground might it cause this efect do you think? I was thinking of just replacing them and see where i go from there. Not an easy set to work on that is for sure.

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  • angelo40 Apr 22, 2008

    Robotek. I could not find any service manual or scematic for this unit. Would you be able to provide some test points for me to check to determine the problem?

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Hey no worries mate... did you get the other post. We can keep working from there :)

Posted on Apr 26, 2008

  • Graeme Ross
    Graeme Ross May 05, 2008

    hey man, how did you go, would be cool if you could close off this ticket with a rating... is still in my pending list :) Happy to help you sort it out. :)

    Graeme

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I don't have a schematic for this unit, however good design would not demand matched transistors.
If a transistor has shorted, USUALLY mating transistors have been damaged. I am not sure how "5" outputs are configured as usually there is symetry and an even number. If the "5" are all on one side and there are mating trnsistors of another number, then likely there is damage to more components and probably back one stage in the drivers or even farther.
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Service manuals are not available on the net for these. They are suplied to service centers only (as far as I know). These are straightforward units however and should be relatively easy to repair. Are you experienced in audio repair? If so, first check the output transistors. I would suspect that one pair are shorted (at least).

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1 Answer

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