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Recent content by grieverheart

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    840AV dead PSU

    Well, I didn’t expect this type of reaction. I thought people here shared my passion for repairing things. It’s not like I know nothing about electronics, and PSUs in particular, this is just the first time I’m trying to repair one myself. Obviously I made some mistakes at the beginning, but...
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    840AV dead PSU

    I successfully created an adapter for the ATX power supply and it works very well! Now, the original PSU also has output AC. Inside the PSU there is a relay which is operated by the 12V rail, which turns on the AC output. I also ordered a similar relay to possibly keep the functionality. If...
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    Quadra 840AV speaker connector

    That seems indeed the connector! Thanks! I'll try to see if I can get aftermarket ones. I'm going to try to crimp them using a pair of pliers, otherwise I'll have to get a crimping tool.
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    Quadra 840AV speaker connector

    The contacts inside the internal speaker of my Quadra 840AV connector are broken. Does anyone know what replacements I need? Also, do I need to buy a crimp tool? Also, does it matter which speaker cable goes in which hole of the header?
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    840AV dead PSU

    Just an update, but I decided to take two approaches. Try to repair the PSU and use an ATX PSU. Fortunately, I swapped connectors with the apple and ATX PSU and was able to get the Quadra 840AV running again! This was a first test and after I confirmed, I quickly ordered PCBs (for the first...
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    840AV dead PSU

    Unfortunately, the PSU I ordered, didn’t have the advertised amperage, so that one is going back. I immediately ordered an alternative one, but soon after I found out that my PC also has a PSU with a quite high 5V rail of 28A, so I can always use that one 😊
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    840AV dead PSU

    Thanks for sharing! This will certainly help. Did you go for splicing or did you use the staple method to transfer the pins to the Mac’s connector? I will order the ATX PSU, and see if I can at least get signs of life from the 840AV. Hopefully it was just the power supply!
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    840AV dead PSU

    I’ve got nothing crazy and I don’t intend to. Also have bluescsi instead of a hard drive. It’s good to know that I can also probably use a better quality PSU with perhaps 20A on the 5V rail.
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    840AV dead PSU

    Problem is, I cannot find any ATX power supply with 30A on the 5V rail from any reputable brands. I assume the Inter-tech I mentioned above is on the look low end.
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    840AV dead PSU

    The reason I asked if I should go with revealing an old one or converting an ATX one, is due to This article. Apparently, the newer cheap ATX psus are not as good as the old ones.
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    840AV dead PSU

    You think so? Everything else looks fine. I’m now wondering if just the MOV short-circuited. I read that this can happen, and indeed catch fire. I can’t find any obvious shorts anywhere. So I’m now wondering if I should risk it and replace the MOV and some of the caps and try again. BTW, I...
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    840AV dead PSU

    Indeed, doesn’t sound very intelligent of me when I read your post! 😅
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    840AV dead PSU

    Bad news, I removed the daughter board successfully, and then went ahead and removed the capacitor with the hanging base. I then went ahead and plugged the psu without the board in, but started hearing burning sound again, I sprinkled some alcohol to try to locate the problem, but it resulted in...
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    840AV dead PSU

    I dusted the psu off this morning, and discovered what seems like a probable blown capacitor — the bottom black plastic is hanging, and on the other side of the board it looks darkened. There is also corrosion on some pins on the same daughter board, and I think at least one more capacitor is...
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    840AV dead PSU

    I had my quadra 840AV (which I recapped and had working) plugged in for some time without using it and randomly decided to turn it on today. Unfortunately it did not turn on. After checking the PSU, I found out I was not getting anything from 12V, only from the 5V rail. After a few minutes, I...
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