Replacement Power Adapter for Commodore 64


26/01/17 - New update on the project here


I am pleased to present a new product to the shop: a power adapter for Commodre 64.

I worked on this project for some time and I finished the final tests.

Compare to other console, the power supply of the C64 is a little weird because it provides AC 9V (1A) and regulated 5V (1.7A).

At first I thought that I would use a multi-voltage power supply but unfortunately the computer does not work with 2 DC voltages.

1) Replaced the 5V DC:
Make 5V presents no difficulty, since the C64 is rated 1.7A, I use a simple step-down voltage (3A max).

2) Replaced the 9V AC:
One might think that replacing this voltage by a DC voltage is correct (as with Pal NES example).
And well no, here we can not do this because this voltage is used to make other voltages:

  • Unregulated 9V
  • 5V regulated via a 7805
  • 12V regulated via a 7812
This is the 12V that we have a problem because there is a voltage step-up before the 7812.

A step-up with capacitor can not raise a DC voltage, it must have an AC voltage.
I'll spare you the details but I will use a square signal 0-12V.

TOD (Time of Day) Clock: to be honest I do not know if the TOD clock works or not because the signal supplied to the IC is not really TTL-compatible.
And then I found no easy way to test this part and I've realized that no program or game uses it (except if you want to turn your Commode into an Alarm Clock ...)
So if you want to use your C64 as an alarm clock, I advise you to stay with the original power supply.

3) The case:
For this first version I decided to use a separate box that can be supplied with 12V (2A).
Simple power supply 12V (2A) from Ebay will be enough to run your Commodre 64. So you can choose US, EU or UK plug.

I will start a batch and the product will be available soon (with and without a 12V power supply).

I will update this post when available.

Update :

04/02/16 - Commodore 64 Power Adapter is available here


Next project : Amiga CD32, Philips CD-i 450 (RJ type plug), Neo Geo CD (depend if I can make the plug)


Back to blog


Keep up the good work, I will buy one.


I’m hereby expressing great interest. :-)

Stephan Schmid

If you do a C128 one I’ll buy one!


I want one. Or two. Or more.


I have that in my todo list but the square DIN plug will be difficult to find.

Retro Game Supply

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