Dodgy PSUs from China

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tricky
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Dodgy PSUs from China

Post by tricky » Sat Feb 10, 2018 4:04 pm

Our DVD player recently suffered a catastrophic failure in the high voltage side of the PSU, so after seeing several components with exhaust marks on the PSU i decided that I would order a cheap replacement from China.

The first one arrived, I had splashed out a whole £4 after deciding that the £2 ones were too cheap!
When it arrived, it was in fact one of the £2 ones and not the one advertised. After an apology from the seller with the excuse that their software had broken and so they hadn't been able to change their pictures for five months, a refund arrived.

I ordered a different £4 one and it arrived today, the boss encouraged me to fit it as one of her costume drama disks was still stuck inside.

I sucked the components off the old psu board to use as a mounting platform, plus some hot glue and wired up the new PSU. The two outputs weren't labled, other than one pad in each pair having a "+" sign.

To my surprise, when I metered them to see which was 5v and which 12v, I discovered that the "+" was actually the "-". I know these things are sometimes a little strange, so I added a load and they were still "backwards".
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I wanted to post in case any of you purchase a little hobby PSU and connect it "backwards", killing whatever you have connected it to.
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I just checked their listing and the one shown also has slightly confusing voltage labels.
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CMcDougall
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Re: Dodgy PSUs from China

Post by CMcDougall » Sat Feb 10, 2018 5:18 pm

Maybe they are for Spectrum & Epson computers, they are arse for elbow too :roll:

looks like you got the DVD out 8)
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Coeus
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Re: Dodgy PSUs from China

Post by Coeus » Mon Feb 12, 2018 11:18 pm

After the thread on deathdapters and rumours of cheap PSUs from China catching fire you're brave. On the other hand I thoroughly approve of giving equipment a new lease of life rather than just scrapping it.

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tricky
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Re: Dodgy PSUs from China

Post by tricky » Tue Feb 13, 2018 1:20 pm

I did notice that some of the cheap PSUs have a warning that they were built as part of a "project", which a guess means by some kind of students or home build returns!

Prime
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Re: Dodgy PSUs from China

Post by Prime » Tue Feb 13, 2018 2:41 pm

Coeus wrote:After the thread on deathdapters and rumours of cheap PSUs from China catching fire you're brave. On the other hand I thoroughly approve of giving equipment a new lease of life rather than just scrapping it.
Indeed, the one place I tell people never to cheap out on is power supplies. Always buy them from somewhere reputable, then you have some comeback if something bad happens.

Cheers.

Phill.

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