yeold

Background

About ten years back I bought a Velleman K7203 as a fun soldering project, and to use as a power supply for a future project.

This will provide a very stable output voltage with <0.5 mV ripple which is pretty nice.

And now, 10 years later, it's time for that future project.

Assembly

The most important thing that was required for PSU after the module itself was a transformer, and preferably toroidal transformer. And those things are not cheap, unless you're lucky and find one second hand.

I got a 230VAC/25VAC 2A transformer that I'm gonna use. And together with that I got a metal enclosure from AliExpress.

I began with drilling holes in the front for the banana plug connectors, and followed the standard pitch of 0.75” between the connectors.

And from the front it will look like this:

After drilling some holes and mounting the power supply and the transformer with some spacers and mounting hardware it looks like this:

I made sure to use a ground cable since I use a metal enclosure, and I also use a C14 connector with a power switch and a fuse as recommended by the PSU manufacturer.

Testing

The PSU in an assembled state is very plain, and it gives a voltage range between 2 to 17.9 V.

Next steps

For now the voltage adjustment is located on the PSU, so one would need to open the case to adjust it. In the future I'd like to have a potentiometer mounted on the front together with a VA meter. And that will be for a future blog post.