GVD Audio Amplifier broken...

Ender
Ender Posts: 603
edited July 2009 in DIY, Mods & Tweaks
I've got a broken GVDaudio (GTD electronics) amplifier, the P6500S, that someone wants me to fix up.

Now, I'm really no expert at this, so I wanted to ask to make sure... but these caps are busted, right?

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dsc00168gev.th.jpg
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SDA 1C, SDA 2A, SDA SRS 2, CMT-340SE, Swan M200MKII, Swan D1080MKII, Behringer MS40

Outlaw Audio M2200 x2, GFA 555 II, BGW 750C

GDA 700, Outlaw Audio Model 990, Sansa Fuze, X-Fi Platinum Fatality
Post edited by Ender on
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Comments

  • Systems
    Systems Posts: 14,873
    edited June 2009
    In the first pic the tops of those filter caps look swelled.Thats an indication that their voltage rating has most likely has been exceeded.Did they also leak out electrolyte around the bottom?
    Testing
    Testing
    Testing
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  • Ender
    Ender Posts: 603
    edited June 2009
    I don't know. I can't tell the difference between electrolyte and some of the glue. There's some sort of dried water mark that looks like it could be electrolyte... but I can't tell if it is.

    7 of 8 of these big black caps have swelled tops. I am pretty sure they are busted. What should I do to fix this?

    I know I will need to get distilled water or something and wash out the electrolyte. Then replace the caps. Do I need to remove all components before washing the CB?

    Also, could other areas have been affected by the busted caps?
    SDA 1C, SDA 2A, SDA SRS 2, CMT-340SE, Swan M200MKII, Swan D1080MKII, Behringer MS40

    Outlaw Audio M2200 x2, GFA 555 II, BGW 750C

    GDA 700, Outlaw Audio Model 990, Sansa Fuze, X-Fi Platinum Fatality
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  • Systems
    Systems Posts: 14,873
    edited June 2009
    You must first be sure that the voltages are correct and within the caps voltage rating. The swelling is likely a symptom not the problem,it will have to be corrected and there could be other problems aswell.Does it blow fuses at turn on?If there is some electrolyte on the board you could try using somthing like methyl hydrate to help disolve and clean it,removing the caps only.That board does not carry any signal audio signal so if you get it reasonably clean it should be OK.
    Testing
    Testing
    Testing
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  • zingo
    zingo Posts: 11,258
    edited July 2009
    I have always tested filter caps by leaving them in the circuit and testing the AC ripple after the caps. If it's anything more than a little, the caps are not doing their job, thus broken.

    You should just be able to do a light clean up from where the caps were mounted and then solder in the new ones. Just make sure you install them with the correct polarity so they don't blow.
    Jake
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