Origami architecture

Architecture in paper You probaly have seen popup cards before. This special kind of popup card is called origami architecture. This card is made from a pattern found at Willem's origamic architecture


  • By: A.A. van Zoelen
  • On: 22/11/2010 18:28:00

Mini arcade cabinet

Pacman in mini style I had a few old Nintendo Gameboy advance handhelds laying around collecting dust. I thought it would be a good idea to turn one into a mini arcade console. So here it is!

I dismantled the GBA to its bare parts and wired up the switches to the various controls on the pcb. For the D-pad control i made a nice looking joystick control from a few micro switches, a spring and a small drawer knob. I still had my flash rom kit to do homebrew on the GBA so i added that one into the gameslot, added a few games to select from and there you go, a mini arcade cabinet was born.

Now not everything is nice and shinny. Because the GBA doesn't have a backlite display the view is rather unclear and dark. To overcome this part i added 4 bright leds in the top of the cabinet. Although this helps a lot it is still not enough so i added an additional bright led on top of the cabinet to give that highly needed bit of extra light on the display.


  • By: A.A. van Zoelen
  • On: 20/11/2010 10:18:00

Christmas card

Christmas card Every year i try to make aspecial Christmas card.

For this year i made this one.
I found this one on crechemania.com and it is looking very nice indeed..


  • By: A.A. van Zoelen
  • On: 19/11/2010 22:10:00

Roomba 530 remotely

Roomba 530 The roomba 530 is a vacuum cleaning robot from iRobot.com. I use it frequently when I leave my house and when i come back all I have to do is to toss out the garbage it collected and I am done. The roomba sit nicely tucked away and out of sight under my furnace. All nice and clear, right?

Not really. Because the roomba 530 version hasn't a remote control I have to go on my knees everytime to push the start button to get it started.There Roomba 530 must be another way to do that. It turned out that something as simple as just push the button can be rather hard.
First of all the size of the roomba makes that the design must be heavier then anticipated to overcome bending of the frame while pushing the button. Also I want to push the button only ounce and then return. I made several experimental designs but this one is the most reliable. A mechanical construction driven by a motor, a relay and two switches. I control this with my domotica system. When I give a start signal a KlikAan-KlikUit Roomba 530 module (some sort of X10 thinggy) will swith the main power on for 15 seconds. Then the motor have to rotate only one time and then stop. After 15 seconds the power goes off again and everything must be set in the right position to be able to start the next cycle again.

Roomba 530

Have a look at the schematic.
When the power goes on the motor will start turning. After about a 90 degrees S1 is pushed and kept in that position. At 190 degrees S1 is pressed shortly and it activate the relay disconnecting the power from the motor. However, because S2 is still closed the motor keeps turning. The relay stays on because it powers itself now. At 270 degrees S2 drops to OFF position and breaking power to the motor. Because of the inertia of the DC motor it will turn slightly more and stops at 360 degrees. After 15 seconds the main power is cut of and the relay will drop to its 'normal-closed' positon and setting the device again in the start position. Nice!


  • By: A.A. van Zoelen
  • On: 07/11/2010 09:43:00

Yes indeedy!

Yes, it's a sheep This paper automata i had around a year or so but i never came to it to build it.
Till now that is!
Isn't she adorable. I find this one so cute. The plan is really very simple and the instructions are clear. It took me only 1.5 hour to make it.
Credits for the design goes to http://www.flying-pig.co.uk


  • By: A.A. van Zoelen
  • On: 31/10/2010 13:50:00

3-Band shortwave crystal radio

Radio overview Because i had so much fun designing and building a AM crystal radio i wanted to raise the stakes a bit. So i designed this 3-band shortwave crystal radio set.
This radio is much smaller then the previous one. Also it only needs a antenna wire to work properly.

Read more


  • By: A.A. van Zoelen
  • On: 7/10/2010 19:53:00

Household items crystal radio

And there it is. I finished the crystal radio set. All the parts needed to make it work are homemade by hand and only commonly available goods are used. This project was a real fun project and making a crystal radio set taste for more. Maybe in the future another one will popup here.
If you want to know more about this project then follow the link below.

Read more


  • By: A.A. van Zoelen
  • On: 8/08/2010 20:36:00

What in a diodes name?

As said in the previous post i am trying to make a crystal set radio out of common household items.

This time i was ready to start work on the diode. I made a small test rig to test the functionality of my idea and to test various materials.
I started with copperoxide. I just heated a small piece of copper till it was dark red hot and let it cool down. I removed the black coating with my finger tip and placed it in my test rig. After some fiddling with the paperclip bent as a needle i got a very faint sound.

This small succes tasted sweet. Next i heated some stainless steel till it got a nice blue shine.
That wasn't succesfull as a crystal material till i added some pencil lead as a needle tip. That was some improvement compared to the previous one but not much more. After that i replaced the stainless steel with a old rusty spatula. This was an instand hit. I got a volume out of the earphone of about 70% of that when using a bought geranium diode. More experiments need to be done.


  • By: A.A. van Zoelen
  • On: 2/08/2010 21:41:00

About caps and coils

I am working on a new fun project at the moment.
For a very, very long time i want to make a crystal radio set but never had the time for it. Now, while cleaning up some boxes i found some materials to make one. A scrap piece of pvc pipe, some wire, an diode of unknown type and a few capacitors. I even found an old crystal earphone. What a gold mine!

A few hours later the coil was wound, all pieces soldered and music was filling my ear. It turned out that I was lucky with the diode. A bit wondered that this actual worked i was looking at that thing i made on my bench.

What if i could make this complete radio all by myself like they did in the old days and make all the components by hand?

On the internet i found a page dealing with a variable capcitor made from cardboard. I had a look at it but i couldn't tell what the value of this variable capacitor would have. Nothing else to do then just make it. It turned out that the capacitor only has a very low capacitance of around 10-30pF. I say something because this thing is rather unstable and completly unusable for me.

Back to the drawning board

I needed something sturdier. The next capacitor i made of pcb or printed circuit board. Its material that is used in electronics. It's an epoxy plate with on both sides a copper layer. I made 8 plates for the stator and 9 for the rotor. After the assemble it was ready for the test
The result wasn't good. Again a very low capacitance. It turned out that there wasn't contact between the different copper layers of the rotor due to the design. Adding a small wire and some solder fixed that but i still wasn't pleased with this version. No i've finished a full aluminium 3th version that is up for the task. More about that one later.

In the meantime i found a nice box to build my radio in but the coil was to big to fit in. I needed a new coil. And if you try to rebuild an antique radio set then you must have a good looking sexy coil. Again because i didn't know what i was up to i had to first make a test model. The coil worked but wasn't stable enough and needed to be handle with great care. I made a new coil but now using wire with a solid core. Also about this one i will talk later more.


  • By: A.A. van Zoelen
  • On: 26/07/2010 17:53:00

Dragon remains

Building a large dragon throughout my garden is still ongoing but rather slow. However, yesterday i had some time to work on it again. I carved this neat looking front leg.
Still a few parts to go.


  • By: A.A. van Zoelen
  • On: 05/07/2010 21:35:00


This necklace with matching hangers was made during a crafts workshop some time ago. 15 Ladies where nervously seeking through several boxes to find the most beautiful beads and other items. Me, as the only male there could only wait for them to finish before i could try my luck. It was a successful event and i went home with this nice gift for my wife.


  • By: A.A. van Zoelen
  • On: 19/04/2010 21:33:32

Post modern Van Gogh

Click me for the full image Another experiment with a tutorial from this great site.

This is me on an undercover assignment in the village of Santa Claus..
I had a wonderfull time in Finland and i was doing very well, In the end i was caught by my daughter who recognized me despite the hat...

The snapshot she made gave me a great opportunity to turn that one into a cartoon-like image.


  • By: A.A. van Zoelen
  • On: 7/03/2010 17:00:52

Light scribe

Two week ago i was on a well deserved vacation in Austria. While trying all kind of settings and functions on my camera i got this idea for writing with light. After a few experiments i got this as a result. Looks rather neat if i may say so.


  • By: A.A. van Zoelen
  • On: 7/03/2010 14:01:02

YooYoo and Hoops

The ground is still frozen solid so i am still not able to continue work in the garden. That gives me time to make a time to make a nice paper automata. I found this one last week on the internet.
It was great fun to make.

Click on the image to see it in action.


  • By: A.A. van Zoelen
  • On: 7/03/2010 13:42:13

Whaz the wabbit?

A few months ago i saw some nice images of paper art inside a toiletrol holder. I did emptied mine resently some i gave it a go.

The moon is just shinning through the clouds.

Can you see where the little rabbit lives?


  • By: A.A. van Zoelen
  • On: 7/03/2010 12:33:32

Typographic art

What was i thinking? Lately i was bored. Now being bored isn't always a bad thing. Why? I'll give you an example. As i said i was bored and i was just cruising the internet. Clik here, click there. I ended up at this great site that had all kind of graphic tutorials and examples. There i found this tutorial.
The above picture is the result.


  • By: A.A. van Zoelen
  • On: 6/03/2010 10:04:02


For some time now i am automating my house with sensors, motion detectors and remote switches. But one thing stayed the same all this time. The audio system. Now it's time to reshape that and go all the way. So what did i try to accomplish? Actually not that much. Just listening to audio such as playlists, internet radio or any other source that i could tap into with my server. And i wanted to listen to it in every room in my house that i entered but the music had to be turned off again if anybody wasn't in to room. I was able to do that all. I have audio in every room and even a nice bonus. Also the garden is integrated now into my domotica system. You can read more about it in this article on this forum link (Domotica forum).


  • By: A.A. van Zoelen
  • On: 12/01/2010 21:14:02

Postings in 2009