Category Archives: Projects

This category contains all projects.

The Fan Controller Wrapped Up

Yesterday I found some time to put the fan controller in a casing. I used a very cheap no-name case with the dimensions 130 × 68 × 44 mm. First I drilled some 2.5mm holes into the lid, and fastened the Arduino board on it using M2.5 spacers. You see the bottom of the case in the photo – I mounted everything top down, because this simplified everything.

I experimented with the spacer size, until I found the right height, so the display is more or less at the same height as the case bottom. Next I put very small bits of double sided tape onto the corners of the display and put the case bottom on top of the lid. After removing the bottom, the exact position of the display was marked at the bottom with these double sided tape bits.

First I drilled four holes at the expected corners to see the position from the other side. Next I used a Dremel tool to cut the rectangle out of the case.

As usual: This was my expectation of the result… 😉

lucky-resistor-2

…, and this was the actual result:

lucky-resistor-3

No, seriously, I did not expect much. I just hoped the controller will fit into the case and I cut the rectangle at the right place. So, this worked out very well.

Fan Controller Project

Recently I had the problem some expensive components did overheat in my server rack. The ventilation was not optimal and I had to install additional fans. Because this rack is in my office and I like a quiet working place, the ventilation had to be as quiet as possible.

First I thought about buying a off-the-shelf product, but then I realised: If this controller does not work as I expect and the fans will spin too fast/loud, this will drive me crazy over time. So I decided to build a own fan controller. A very simple one, where I can write own code and tweak it until it runs as I like.

On the project page I describe how to build this particular controller. It is not meant you really reproduce this same controller exactly as shown, but maybe understand some basic principles to build your own controller.

Continue reading on the project page!

Outmoded Sequencer Part 2 Ready

I just finished part 2 of the project description for the Outmoded Sequencer. In this second part I describe the steps from the prototype to the final device. I copied the preface from the page after this link .

Outmoded Sequencer Part 2

(Preface from the project page)

Building the Outmoded Sequencer was a really interesting project where I learned a lot. It was the first project with a custom designed PCB. Usually I just solder everything onto stripe boards, because I only produce one single device. The complexity of this device with the matrix forced me to design a proper PCB, soldering everything on a stripe board is feasible but requires more space and a different approach for the matrix.

Not everything turned out as well as expected. First there was the idea with the matrix using steel balls as switches: Even with the magnets generating a certain force to the pads, the steel balls do not connect as reliable as I would like they do. As you can see in the demonstration video, it is still possible to have a lot of fun playing with the sequencer – however better connections would make the experience even better.

Should you build your work Outmoded Sequencer? Yes, absolutely! But you should definitely use a different approach for the matrix. Best first only experiment with the matrix part until you have a working solution there before you add the other parts around.

Should you use the provided PCBs? No, better design your own board especially implement the matrix in a different way.

Should you use the circuit design as provided? Yes, definitely! The design is, in my opinion, a very good start and should give you a reliable and working device with minimal effort. Keep in mind: This is a minimal design and there and many ways how to improve certain aspects of the circuit. So feel free to address the problems if you have components left, to spend on this project.

Continue on the project page

 

Outmoded Sequencer Live Demo Video

Today I made a short live demo of the Outmoded Sequencer. I just added briefly some audio effects at the end of the video, so you can hear the real sound of the device. Adding effects is a really great way to turn the beep sounds in interesting music.

You can also see the connection problems sometimes happen. A short push on the steel ball solves this problem usually.

Let me know what in think in the comments. Next I will finish the second part of the guide, where I explain how everything was built.

Outmoded Sequencer Finished!

Hurray! I just finished the final Outmoded Sequencer device. The tuning of all frequencies was way faster than I expected, because I used a new method. Have a look at the following photo gallery before I tell you some details.

You can see the device is build like a control desk, with the PCB a little bit at an angle. The left knob on the top controls the speed of the sequencer and the right one the volume.

A did a few tests already and the idea with the steel balls is working, but not great – just ok. So sometimes they do not connect and you have to move them a little bit until they make contact again. Most of the positions are working always without problems.

It is a great fun to play with the device, changing the pattern while the melody is playing. Now everything is finished, I also can move two steel balls at a time which can create interesting variations.

Next I will do a detailed video, where I demonstrate the final Outmoded Sequencer. It should give you a better impression of the device in action. I will also setup a complete filter chain, so you can experience how easy you can use the sound of the sequencer as input to do various interesting effects.

I will also add the second part of the project page, where I explain some of the details about the magnet matrix and how the whole thing is built.

There are seven absolutely perfect PCBs left, so I think about to give them away if someone is interested into building the project. But be aware, this is no kit, just the plain PCB. You also have to use the exact same components as I did – or at least ones which perfectly fit into the holes. All components should be available to buy at various stores, and I will provide the exact part numbers.

Video: Assembling Final Outmoded Sequencer PCB

Here a short update on the progress with the final Outmoded Sequencer project. I did the whole assembly of the final PCB and connected everything. You can see part of the soldering process in the following video:

I accidentally cut a route on the bottom of the PCB, so I had to fix this with a short wire. It is not visible on the final device. The magnet matrix mentioned in a previous post is already securely fastened to the bottom and holds the steel balls in place.

There are only the final adjustments of the frequencies left to do. I have to tune each tone and add the last four missing resistors.

Building a Magnet Matrix

I did many tests with the Outmoded Sequencer how to use steel balls as switches. While this is working very well from the electronic point of view, one problem was the steel balls tended to fall of the PCB easily and roll under furniture.

To hold the small steel balls into place I am building a matrix of 8×8 neodym magnets. This magnet matrix is later mounted below the PCB, so there will be one magnet for each pad on top.

I am using these small, but very powerful neodym magnets. They have a diameter of 4 mm and a length of 5 mm. You can get this magnets, any many other shapes, from Supermagnete, they deliver the magnets to almost all European countries.

magnet-matrix-02

I started by using the holes in the PCB as a template to put marks onto a piece of plywood. Best is using a stitching awl, to create small holes. Next I drilled 64 holes with a diameter of 4 mm into the plywood.

Continue reading Building a Magnet Matrix

The Final Outmoded Sequencer PCB

The final black and gold PCBs for the Outmoded Sequencer arrived. They really look great with a nice contrast between the solder mask and the silk. The surface is somehow glossy and the routes are barely visible under the black solder mask. Now I really hope I will not find any further problems with this PCB.

Outmoded Sequencer Final PCBOutmoded Sequencer Final PCB

This nice PCBs were produced by PCBWay. As you can see, the quality of the PCB is very good. They produced it in three working days and it was shipped in three days via DHL.

The final version is 8mm wider and 10mm higher than the prototype PCB. You can also see how I rearranged the components to move the matrix more to the center.

A very interesting fact is, that I could simplify the routing, because I mounted the resistors and diodes back in the normal horizontal way. This created space under the components which I could use for the routes. Here the routing of the final board:

Outmoded Sequencer Final Board