Friday, August 13, 2010

Altec Lansing MX5021 Dead

My MX5021 is dead.
Don't know which part is dead without the diagnosis tools.
Guess it must be the signal path because there is no hum when it is switch on until I play the music.
Plus, my test pen short circuit and pop the TDA7295 while checking each of the components so it is totally dead now. I also lazy to fix it already, going for bookshelf.


My advise, handle it with care to prevent any impact onto components during modification and plan which component and brand to use before start your work. Keep soldering and de-soldering will damage the PCB trace and try your best not to touch the SMD components with naked hand because they are sensitive to electrostatic.

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17 comments:

  1. since the unit is spoiled. How about let it go for a price?

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  2. Hey, I just recently got my brother's MX5021. He told me he was having some problem with them and they don't produce any sound. I anyways got them to check. I have no experience with speakers. I was just wondering if they can be repaired. The woofer is able to power up the control pod and the speakers but there is no sound. The satellites work fine when I connect them to some other player but they don't work when connected to MX5021 woofer. I got the woofer checked with local electrician and he said all the internal wiring is fine. Any clue?

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  3. Hi VC, I need a help on my MX5021. I modded it years ago and it works fine until recently some static noise noticed from the left channel by just turning "ON" the speaker. I swapped satellites, cables, unplug the input 3.5mm jack and the same left channel produce static noise. So the problems comes down to some component on PCB in the woofer. Futher more, when i listen with headphone connected to the control pod, no static noise noticed. So I guess it must be some component not working well AFTER the signal been amplified for the left channel satellite. Problem is I don't know which components comes after the signal amplification and more likely to cause the static noise. Can you advise on this? thanks a million!

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  4. Hi VC, nice meeting you. I'd mod my MX5021 few years ago and it works fine till recently i notice some static noise from left satellite. Turning the volume up and down didn't help to minimize the static noise, I've tried to swap left and right speakers, cables and unplug the 3.5mm input jack but the static noise remain at left channel. So the problem goes down to the PCB board. Since there's no static noise notice with headphone plug into the control pod, I assume that the problem goes AFTER the input signal been amplified along the way to speaker output instead of control pod headphone output. Problem is, I got no clue that which component seems more likely to cause the static noise and need to be replace. Any suggestion? Thanks a million!

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    Replies
    1. I got the problem like you too. But my speaker is not modified. I found that the problem is not in the power amplifier part. By removing C54 ( input for left channel of TDA7265 ) the noise is gone. So I think the problem is some where before TDA7265. But I don't know. Could anyone help me please.

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  5. My speaker is broken too. I can turn it on but there is no sound. Do you know where I can have it fixed?

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    Replies
    1. I have these speakers at home for repair. I had problem with MUTE/STANDBY pins on power amplifiers. All speakers are dead silent, but the input audio signal is applied to their pins. No output whatsoever. These MUTE pins are powered via transistor Q1 (NPN transistor) on the subwoofer PCB which is controlled from the controlling pod. There is an IC (STsomethingsomething) in the pod that has not stable output of 5V on one of its pins. This voltage comes across the switch in headphone jack (it mutes the speakers when headphones are insterted) and via the cable to the subwoofer's PCB. Simple fix with 1 PNP transistor and 47k resistor cures this problem, speakers are working fine again.

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    2. Hi Bajticzek, I have the same problem on this no sound speaker. Could you help to elaborate more on how to fix with PNP transistor and 47k resistor? I mean where to put that transistor and resistor? do we need to remove Q1 transistor? Thanks for the help in advance.

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  6. Sorry guys, I'm no longer into this.
    It is advisable to get a specialist/technician to inspect it. =]

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  7. Hi, I have a MX5021, but I'm having problem with wired controller, where can I buy or replace this?

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  8. Look for lex on forum.lowyat.net. He has successfully fixed quite a number of MX5021 speakers.

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  9. Hello
    Somehow, during transportation, I have managed to smash beyond any chance of repair both satellites for MX5021. I kindly ask you, if there is no need, for a functional pair or a link to buy them. It seems impossible to find them.
    Thnx

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  10. Hello
    I want to buy a pair of satellites for Altec MX5021. It seems impossible to find them on eBay. Maybe someone, somewhere reading this comment has a pair he does not need and wants to sell it.
    Thnx

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    Replies
    1. salut,
      te mai intereseaza mx5021?
      sunt din bucuresti.

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  11. are you still interested in MX5021?

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