Sunday 12 March 2017

Hi,

here is my design for the C64 and 1541-II replacement power supply.




















Schematics and PCB Layout for Download: Link to Google Drives
The layout was created in Target 3001 (Free to download from http://www.ibfriedrich.com)

Be aware that you are working with mains voltages - only for people who know what they are doing.

Greisi

32 comments:

  1. Nicest homebuilt PSU I have seen - looks great!
    Cool mount for when soldering, where would I found one of those (probably super expensive, but it doesn't cost to ask).

    ReplyDelete
    Replies
    1. Thanks! The PCB holder is a Weller ESF120 - and yes it it very overpriced. But it is still the nicest one I have ever tried (at least for THT). It is pretty much everywhere available where you can buy Weller soldering gear (Although they sometimes market the holder under the Xcelite brand).

      Delete
  2. You can consider using one of these for a real retro Commodore look and feel.http://www.maplin.co.uk/p/vented-psu-enclosure-6-n08kh

    ReplyDelete
    Replies
    1. Love that one - but it's only available to UK customers as far as I can tell (have been mailing with Maplin). It may not be more expensive than the one currently chosen.

      Delete
    2. Wow - That one would really look awesome. Really nice find!

      Delete
    3. This link seems to be broken. Can you specify the brand and product name?

      Delete
  3. This comment has been removed by the author.

    ReplyDelete
  4. This comment has been removed by the author.

    ReplyDelete
  5. This comment has been removed by the author.

    ReplyDelete
  6. nice project, I really like the enclosure. Electrically, I would add an EMI filter to the mains input to filter out distrubances from outside.

    ReplyDelete
    Replies
    1. Thanks! I thought about using a filter on the input - but given it is still a linear transformer (which also acts as an lowpass filter) I decided against it. And designing / choosing an EMI filter is not always strait forward - at our company we had multiple issues where EMI filters created a resonant circuit and started to oscillate and that pushed the output voltage way over the nominal operating voltage which triggered various OVP circuits. Since then I am a bit cautious with EMI filters.

      Delete
  7. nice top see more people doing this project. Here's mine: http://danieleredivo78.wixsite.com/c64psu

    ReplyDelete
    Replies
    1. Hi! Very nice build - Especially the OVP is a really nice touch.

      Delete
  8. hi i am trying to build this power supply, but the transformer is 'unobtanium' in the us (also not sure if it can work with 120vac). any alternatives for it?

    btw thanks for the build and sharing
    ernesto

    ReplyDelete
    Replies
    1. Hi,
      first be aware that my design uses 230V AC. The PCB would need a slight redesign if you want to use it with 120V AC (The primary windings of the transformer needs to be in parallel for 120V).
      Unfortunately I don't know many electronic distributers in the US (Besides Digikey, Arrow and Mouser). None of them seem to have the Transformer I have used.
      And given that these PCB mount Transformers are pretty much all custom designs, I don't think there is an easy 1:1 substitute available.

      greisi

      Delete
    2. Not sure if you're still looking for the transformer, but try looking on Newark Element14 Electronics site, www.newark.com

      Delete
  9. Try and find a close match, then change the PCB to fit...

    ReplyDelete
  10. Hello im in the UK England so i can use all the same components ?

    ReplyDelete
  11. Great project, pcb looks great with components, more organized than the usual PSU. I have ordered components and pcb's and have finished the 1541 II PSU. I put the 220 volts in and it did not explode and my town still exists :-). The output is + 5 volt and + 12 volt, checked with a multimeter. Then I tried it on my 1541 II, which did not explode either, but the green light stays on. If I use an Amiga CD32 PSU (which is the same as thee original 1541 II PSU) the green light goes off and I can access it with my C64. So.. I need your expertise, what could it be??

    Philip.

    ReplyDelete
    Replies
    1. Found it myself: the ground of +5 volt and + 12 volt are not connected, did not expect that. I solved it by soldering the ground of the + 12 to the ground of the + 5 pin.

      Delete
    2. I priced the components from the BOM supplier! Nearly £100 for one unit! Bridge rec/transformer were nearly £50 alone! Crazy.

      Delete
  12. Have you consider designing an Amiga replacement power supply?

    ReplyDelete
  13. Looking at your design, the voltage regulator does not include an overvoltage protection itself. So, from your schematic, you used just a zener diode to limit the voltage. I wonder if that is a bit risky, since the zener will just short to 0V the voltage excess and lots of current will go through it, but this is not the bad point. The bad part is: who is going to turn off the power in such case? After a few minutes the zener will burn, unless you dissipate the heat properly. Other than that it looks nice. I like the pi filter between the rectifier and the regulator, that will clean dirty noise really well.

    ReplyDelete
  14. Have you done any thermal test at full output (3A from 5V)? Would be interesting to compare my findings (based on a similar not not equal 1:1 design) with yours.

    ReplyDelete
  15. Would you mind consider to sell "solder at home" kits? I really would like to have one for my c64c as well.

    Thanks for Sharing greisi

    ReplyDelete
  16. Yeah! Anyone who would provide a kit for these PSU:s would make my day.

    ReplyDelete
  17. Amazing job Greisis! You're a genious. I don't know much about electronics but like your general philiosophy of keeping it simple.

    ReplyDelete
  18. Hi! Great work with your C64 PSU replacement,but I‘m wondering where I can buy the PCB? (or do I have to order them by myself?)

    Thx

    ReplyDelete
  19. Wow…outstanding service and products to meet our office needs. I Love all and the colors you choose are perfect. I want this furniture for my new house. Thanks a lot for sharing
    wooden cot manufacturer in arumbakkam

    ReplyDelete
  20. This is a fantastic build. I don't know if Greisis continues to follow this blog, but if not someone else might know this, what enclosure is being used? And also what sleeved grommet? I've been having trouble finding wide enough sleeved ones like those Greisis uses.

    ReplyDelete
  21. Hello you are a excellent engineer and I would like build my own from your design. I have ordered pcb's before but the designers have allays specified thickness and size of pcb required may I ask do you have this information to hand. Thank you

    ReplyDelete