Replacing 4 diodes with a bridge

[Pentium4]

I want to replace these Diodes with a GBU808 (I know overkill...) and I see where the positive side is but I'm not sure where the other pins of the rectifier would go, I know it's probably pretty simple, I just don't want to do it wrong

[northpoint]

Re: Replacing 4 diodes with a bridge

Why do you want to do that? I would think just leaving them the way they are. If you do blow one then you dont have to replace the whole bridge chip.

Northpoint

[ben7]

Re: Replacing 4 diodes with a bridge

Here you are P4

Blue - AC
Yellow - DC (marked + and -)
Red - unused

[Pentium4]

Re: Replacing 4 diodes with a bridge

Thank you ben7!!! It's a Sun Pro...I already added an X cap, replaced the 220uF input caps with 470uF, and replaced the fake Y caps with real ones, so the input will be in good shape

[ben7]

Re: Replacing 4 diodes with a bridge

Thank you ben7!!! It's a Sun Pro...I already added an X cap, replaced the 220uF input caps with 470uF, and replaced the fake Y caps with real ones, so the input will be in good shape

Mind if you could get us a pic or two of the final job (when the bridge-rectifier arrives)?

[Pentium4]

Re: Replacing 4 diodes with a bridge

Yeah! Here is the before and after, and a pic of a typical Chinese cap lying about the specs! I think maybe some of the little caps on the 5VSB are bad because this thing has no signs of life. I will work on it more on the 31st and hopefully get it going

[TELVM]

Re: Replacing 4 diodes with a bridge

Man that capacitance/ESR gadget is exactly what I'm looking for ! Where can I get one of these? How much does it cost?

[Pentium4]

Re: Replacing 4 diodes with a bridge

Isn't it awesome? I saw tom66 had the ESR60 so I bought the newer version. I found one on ebay, it's ~$128 (97€) shipped but worth it!

[vinceroger69]

Re: Replacing 4 diodes with a bridge

http://www.ebay.co.uk/itm/NEW-Peak-A...item519f47c5a1

[TELVM]

Re: Replacing 4 diodes with a bridge

Thanks!

[tom66]

Re: Replacing 4 diodes with a bridge

I elected to get the ESR60 because I didn't think the audible alerts would be useful (it's £20 extra), but do you find them useful?

[ben7]

Re: Replacing 4 diodes with a bridge

Yeah! Here is the before and after, and a pic of a typical Chinese cap lying about the specs! I think maybe some of the little caps on the 5VSB are bad because this thing has no signs of life. I will work on it more on the 31st and hopefully get it going

Thats not good!

Was it working before you did the mods to it?

[Pentium4]

Re: Replacing 4 diodes with a bridge

I elected to get the ESR60 because I didn't think the audible alerts would be useful (it's £20 extra), but do you find them useful?

It can be useful, plus it detects ESR up to 40 ohms compared to 20. I saw one (only slightly bulging CapXon) hit 26.6 ESR!!!!

Thats not good!

Was it working before you did the mods to it?

No it wasn't working before. But the start up cap is a Ricon so it's probably toast and needs to be replaced

[ben7]

Re: Replacing 4 diodes with a bridge

No it wasn't working before. But the start up cap is a Ricon so it's probably toast and needs to be replaced

Oh no wonder ... a noname capacitor.

It looks like this has a two-transistor 5vsb, so if you don't get it fixed with new caps, then you could do the smps chip mod. (Like the VIPer22 or DM311)

[Pentium4]

Re: Replacing 4 diodes with a bridge

Yeah hope it works! But if it comes to that then I should give it a shot Some cap names make me laugh....one of the caps is "Sapcon"

[ben7]

Re: Replacing 4 diodes with a bridge

Yeah hope it works! But if it comes to that then I should give it a shot Some cap names make me laugh....one of the caps is "Sapcon"

I'll never forget the 'Scatronics' brand capacitor I found in a el-cheapo computer speaker

[TELVM]

Re: Replacing 4 diodes with a bridge

I'm slightly ashamed to ask , but what do you think of this ?:



http://www.ebay.co.uk/itm/NEW-TRANSI...item25791913e6

[dmill89]

Re: Replacing 4 diodes with a bridge

Not sure what your plans for that PSU are Pentium4, but it appears to be very similar (although slightly cheaper judging from the heatsinks) to this one I rebuilt a while back if you want some ideas.
https://www.badcaps.net/forum/showth...hlight=gutless

link directly to the rebuild post:https://www.badcaps.net/forum/showpo...93&postcount=8

[Blargh523]

Re: Replacing 4 diodes with a bridge

I'm slightly ashamed to ask , but what do you think of this ?:



http://www.ebay.co.uk/itm/NEW-TRANSI...item25791913e6

If I got that, first thing I'd do is get some socket-strips and solder then on.

[mockingbird]

Re: Replacing 4 diodes with a bridge



This is pretty good resolution for such an inexpensive device, no?