Altec MX6021

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  • Behemot
    replied
    Re: Altec MX6021

    You tell me, just got this BIG sub from Cambridge-whatever-something under Creative, expensive like hell, also SMPS in there (no wonder with the power the thing puts out) and ofc all caps busted. And vitually TONS of that chloroprene stuff EVERYWHERE.

    This is just crazy! Power supplies went ahead and even the El Cheapos start using two-forward topologies at least. But in audio equipment, everybody continues to produce the same shit they used to. Often even worse.

    When you start testing it, I suggest the lightbulb in series. Often it takes one bad SMD components to make the PWM driver explode again. This hould limit the current and protect it, plus you see right away there's a problem.

    Leave a comment:


  • ant3202
    replied
    Re: Altec MX6021

    Originally posted by Behemot
    OMG! SMPS in speakers and chloroprene glue on top of that! What crap is this?

    1R0 is likely, it is fusible resistor which acts as fuse when something goes wrong on the primary.
    thanks for your help Behemot

    you are right.... really crappy.... SMPS inside is really.... (
    older models were using transformer...

    can I say to change all to 1R0 ???

    i had checked.... the ic chip is busted, guess drawing too much current, burning the smd resistors and pcb 1.6A FUSE.

    as a precaution ... i will also change the filter capacitor and misc to better and reliable one.

    as checked with some tech guys ..... seems this board fails quite often.

    now no more decent stuffs from altec lansing...

    plantronics ... and stuffs are really going down......

    Leave a comment:


  • Behemot
    replied
    Re: Altec MX6021

    OMG! SMPS in speakers and chloroprene glue on top of that! What crap is this?

    1R0 is likely, it is fusible resistor which acts as fuse when something goes wrong on the primary.

    Leave a comment:


  • ant3202
    replied
    Re: Altec MX6021

    Originally posted by CapLeaker
    there are 5 smd resistors in parallel they should be all the same rating. I would change all 5 of them out.

    yea, CapLeaker, thanks for the tips, definitely it need to be changed.



    need help to identify... as it is badly burnt...
    i think it could be 1R0 but i might be wrong.
    Attached Files

    Leave a comment:


  • CapLeaker
    replied
    Re: Altec MX6021

    there are 5 smd resistors in parallel they should be all the same rating. I would change all 5 of them out.

    Leave a comment:


  • ant3202
    replied
    Re: Altec MX6021

    Hi Jazzie366

    thanks for the tips...

    You are right, the SMD has been burnt and i cannot read the values properly.
    Perhaps i need to ask people around and compare on it.

    Yea, i can lend a smd rework station from someone.

    Leave a comment:


  • jazzie366
    replied
    Re: Altec MX6021

    Originally posted by ant3202
    Hi All , greetings, someone pass a Altec Lansing MX6021 and I would like to learn how to repair it.

    The issue is there is no power to the speaker set.

    Note: Mods please move this post if you think it is in the wrong section.

    Upon inspection of the speaker power board, there were burnt components, of the resistors. the resistors were FUBAR.

    The power transistor seems to be shorted and I'm planning to replace those.

    The fuse is also open

    Normally for this caused? faulty filter capacitor? transistor? or shorts?


    As attached, it seems that some have gooey black stuffs on it.... i suppose glue become conductive?


    Many Thanks
    Well, the first obvious thing I can see is an exploded SMD resistor.

    Nothing else looks too bad other than shit got really hot due to the glue being browned.

    You're going to need an SMD rework station and a schematic to repair this, you up for that? The rework station isn't expensive, 60$ will get you one that can do the job.

    Leave a comment:


  • ant3202
    started a topic Altec MX6021

    Altec MX6021

    Hi All , greetings, someone pass a Altec Lansing MX6021 and I would like to learn how to repair it.

    The issue is there is no power to the speaker set.

    Note: Mods please move this post if you think it is in the wrong section.

    Upon inspection of the speaker power board, there were burnt components, of the resistors. the resistors were FUBAR.

    The power transistor seems to be shorted and I'm planning to replace those.

    The fuse is also open

    Normally for this caused? faulty filter capacitor? transistor? or shorts?


    As attached, it seems that some have gooey black stuffs on it.... i suppose glue become conductive?


    Many Thanks
    Attached Files

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