I have a C64 which had a non-functioning power supply. Fortunately it did not blow the computer. On opening the PS I found the simplest, crappest circuit ever. Using the meanwell (about $9) and this guide I was able to get it back working perfectly. Thanks
I have the same c64 supply and others like it non potted. All are putting out good voltage. None the less I wired a buck convertor into it without ripping out the original board. I just bypassed it. Works fine that way.
If its not potted then its not a brick. Some are half potted. I opened a black wedge which is half potted and I wired in a buck convertor inside to step down from 12v dc and I set it to 4.95v. I then changed the outout cord for one to suit my Plus 4. I wasn't sure if 4.95v was too low but it seems ok.
Inadequate cooling design was the reason these original bricks died. Either the brick manufacturer make a better design by adding a larger multi-finned heatsink -- WITH a fan -- at higher added cost to the C64 package ... OR make it the way we actually got them, at the lower cost. Unfortunately, Tramiel decided on the latter to fit his mission statement "For the Masses, Not the Classes". The better design would have made the thermal transfer from regulator & transformer conducting just as fast to heatsink & fan at same rate as the heatsink & fan would have forcefully radiated to the much lesser dense atmospheric isolator. Instead, the design we got was collecting & trapping heat faster than it could "boil" off into the air, thus the heat would boil inside the regulator, transformer & surrounding components instead. It was a cost/quality tradeoff. I'm sure they weren't even looking at heatsink thermal transfer design equations, or if they did, they minimized parts costs as much as possible. Think of IBM PC power supply units where you rarely see one without a fan, otherwise it goes up in smoke. There would have been many more C64 users (and vendors) that stayed with the Commodore for a few more years had their bricks not died, delaying their eventual migration to 16/32 bit platforms. While the C64 became popular & historic, it would have been a much sweeter ending with a better heatsink. That not even includes what happened with the IEC bodge work giving us slow floppy drives. Hindsight is 20/20.
This is the one I used because it was cheap and readily available www.jaycar.com.au/6-3-15v-15va-1a-multi-tapped-type-2155/p/MM2002 I just tapped off the 0 and 9.5v terminals and it works fine. But if you're not in Australia then this probably isn't an option. Just look for a mains to 9vac that can handle at least 1Amp
Nah, she runs pretty cool. I was going to do a follow up video showing the transformer install on my other channel TheRetroChannel but never got around to it. But you can check out Mr Lurch's Things on RU-vid. He did the same mod but he also filmed the transformer install.
Yes, at least it did work for me. I also had a C128 power supply and replaced the internals with the same meanwell rs-15-5. I believe the original is 128 PSU is rated at 2.5A
@@Sawickipedia Something of a success story. Today I had a crack at upgrading a black brick of death like the one in the vid, and didn't go well. Getting 5v on the pin (can't test 9v on my multimeter) and for a while it kept tripping out my Sav64. When I could dial it in to not trip it out I was getting nothing onscreen, not even a black screen. It wasn't my main C64 psu, it came in a bundle I got a few years so I wasn't too worried. Don't even know how well it worked to begin with, and it was more of a test run for the C128 psu. Opened up the C128 psu and was able to figure out what wire was what. Wired it up to the RS-15-5, fitted a fuse holder on the 9v, dialed the pot down to spot on 5v, plugged it into the C128 and it worked! Trimmed some wires so I can get the case back together (had to clip the "holder" in the lid a bit too), plug it in and black screen. Open it up, blown the fuse (2A, asked for 3A but Jaycar gave me the wrong ones but probably should have been lower anyway). Bung in another fuse, get the case back together and it's working again. Been running it for about 40 minutes or so now and been fine. I'll have another go to see what went wrong with the C64 psu, but otherwise this video was really useful for even a novice like me. Have to throw a couple of shekels your way. :D
