Hi,

I used to enjoy your channel, how come you haven't posted any new videos in almost a year!!?? I remember especially the video where you had to buy a third-party flyback to fix an old CRT. That's why I like videos from third world countries, the hardware worked on is usually 80s...

That PSU looks like a Young Year... You will probably be very disappointed when you open that thing up to find that it's probably only a 300W PSU -at best-, though you never know (I am judging by how small the PCB looks through the grill holes from what Iittle I can see). Judging from the rail ratings on the label, it may have been built in 2008, but it's using a ten-year old 5V rail heavy design (Newer designs have much higher 12V rail ratings, 22A per 12V rail is relatively puny for a 700W+ PSU - if it is even indeed that).

Keep in mind that many capacitors nowaday don't bloat but will still either test completely short or very high ESR when taken out of circuit. So unless they're Japanese brand (Which I doubt, Young Year likes to use Fuhjyuu or other no name stuff), or possibly even Taiwanese brand (Teapo), you should probably replace them if you plan on getting any meaningful use out of it.

That's a Logisys. Made by Keerda, IIRC.

It might be able to put out 350-400W after a full re-cap, but I recommend you err on the side of caution when putting it under load, because every Logisys unit I've encountered has had the overload protection removed.

mockingbird wrote:

Hi, I used to enjoy your channel, how come you haven't posted any new videos in almost a year!!?? I remember especially the video where you had to buy a third-party flyback to fix an old CRT. That's why I like videos from third world countries, the hardware worked on is usually 80s...

Thanks for the kind words! I haven't updated my Youtube channel and blog for a long time because real life and its responsibilities have kept me pretty busy and making repair videos as a one-man show is actually pretty difficult. I also got away from Internet forums for a long time and just now I'm getting back into it, also I had been without Internet access at my house for months and I'm now on shitty ADSL for the time being.

I don't take offense to the third world thing, but here in Chile pretty much the opposite happens. People are way too happy about getting the latest and greatest and just chucking perfectly working equipment in the trash because it's not trendy anymore. Repair techs are also seen as sleazy so people prefer replace over repair. Good for scavengers like me, but ultimately bad for the environment. The people that come to me who want to get obsolete/vintage gear repaired are a pretty small minority.

mockingbird wrote:

That PSU looks like a Young Year... You will probably be very disappointed when you open that thing up to find that it's probably only a 300W PSU -at best-, though you never know (I am judging by how small the PCB looks through the grill holes from what Iittle I can see). Judging from the rail ratings on the label, it may have been built in 2008, but it's using a ten-year old 5V rail heavy design (Newer designs have much higher 12V rail ratings, 22A per 12V rail is relatively puny for a 700W+ PSU - if it is even indeed that).

Indeed that's why I asked, it could be one of those and in that case I don't want to waste my time on it.

Old Thrashbarg wrote:

That's a Logisys. Made by Keerda, IIRC.

Thanks! With that piece of info I've found the exact model too, it's a Logisys PS650U12.
With that I started looking around for reviews and a good number of them are negative. I was kind of expecting that, but on the other hand it's supposedly 80+ certified and it sure feels nicer than most "800W!!1!!oneone" PSUs. I might have a look at the caps later. 😉

Thanks again! 😀

Judging from this review of a similar model, it looks like it has decent input protection (You might want to replace the four diodes with a bridge rectifier) and good secondary filtering (meaning actual filtering coils on the secondary instead of wire bridges)...

What the PSU noticeably lacks is a 5VSB IC and instead relies on the "two transistor design". You might want to check out the "badcaps.net" forum. There are some posts by everell (and later "LDIsHere") which are particularly interesting and that deal with implementing a 5VSB circuit on such PSUs... I think your technical ability is much better than mine and I would learn a lot if you made a video about this (Just giving you an idea 😉)

I don't take offense to the third world thing, but here in Chile pretty much the opposite happens. People are way too happy about getting the latest and greatest and just chucking perfectly working equipment in the trash because it's not trendy anymore. Repair techs are also seen as sleazy so people prefer replace over repair. Good for scavengers like me, but ultimately bad for the environment. The people that come to me who want to get obsolete/vintage gear repaired are a pretty small minority.

Don't worry. I live in a supposedly "first world" country (Canada), and I ride my bike sometimes looking for discarded electronics to play with. Initially I was almost alone in this endeavour, but now there have got to be at least 10 other people (and with cars!) driving around taking everything and leaving precious little for me (One Mexican guy in a big white truck even tried to take my bike while I got off of it to look at a discarded aquarium)... Sometimes I wish I could live in a place like Chile, and I would, were it not for fear of military coups...