Monday, October 8, 2012

Arduino Hydroponics

For a long time I was looking for an excuse to get into hydroponics. And time too.
I had some Arduinos and some PICs lying around the garage, but they were allocated to some other projects and I didn't want to touch them.
So when I got a Arduino Nano last month I decided it was time to spend a Saturday working on my hydroponics prototype.

Strawberrys and lettuces.

So I hacked some PVC pipes, a small fountain water pump, a 433Mhz remote controller 2 channels with a receiver equipped with 2 220V capable relays.


The fertilizer I use in the water is also homemade, humus based, produced by earth worms. They eat leftovers from vegetables, fruits and... well... horse shit.
I programmed the Arduino to water more during the day and less during the night. Next step would be incorporate some temperature sensors, light sensors and humidity. And solar power it all. Pretty permaculturish.

Saturday, September 15, 2012

Ekoparty 8 edition

Ekoparty is coming, September 19. I wish I could be there for many different reasons. It's full of great talks and speakers, I hear it has good after parties and, of course, it's in Buenos Aires. It's probably the best security conference in Latin America.
In particular, I'm looking forward to see CRIME in action. Oh, you don't know what CRIME is? Wake up!?

Saturday, September 8, 2012


Heard about RTL-SDR? Well, I didn't either until some months ago. You can start here.
Basically you can use a regular USB DVB-T dongle, the ones you use to receive TV, as a software defined radio, a.k.a, frequency scanner. Well, kind of.
The concept in itself is pretty cool, so I decided to grab one of those and start to play around. You can do lots and lots of stuff with these, but I always wanted to see if I could pick some satellite transmissions.
You know, the crazy guy in a barn picking up radio signals from outer space, listening to ET phone home. So after some work compiling and hacking code I came up with my desktop having:
  •  GNOME predict, awesome app for satellite tracking.
  •  gqrx, IMHO the best app to monitor the √¶ther, connected to wxtoimg
  •  wxtoimg, to decode NOAA satellite info
  •  an homemade dipole antenna
End result? mind = blow. Not really, no, but I managed to get some pretty cool pics. And watching it appear realtime on my screen gave me the butterflies.

 NOAA 19 Weather Satellite data as it passed over Europe, filtered with wxtoimg.

Thursday, April 19, 2012

HES 2012

That's right! I was there again! deadbytes house again! And this time we pushed it to another level, eight people sleeping in the same room. Oh, and we won the wargame... again! :D
To be completely honest, my team did much of the work themselves. 
I don't even want to get started on the quality of the talks and the awesomeness of those guys. If you like the security world, no matter which colour your hat is, you should be at HES.
You simply have to.

Saturday, February 4, 2012


Armindo, the cyber janitor.

Who is Armindo, you might ask. Armindo is another project from my hackerspace. Armindo is going to be a cyber janitor, which will allow the members so physically login to our hackerspace. He will have several modes of identification, namely a webcam (live) that recognizes QR-codes from members card for active login.
If you forget your card, don't worry, just bring your cell phone.
Armindo is going to be equipped with bluetooth and wifi, that will permanently be scanning for known mac addresses of members for passive login. This way, you just have to be nearby and he logs you in automatically.

But his main feature is that he randomly  speaks Chuck Norris jokes via festival. :P


Monday, January 30, 2012

Hack yourself a USB microscope

This really couldn't get any easier. I found myself at my hackerspace with an incredible amount of lazyness in my hands. Well, lazyness to clean up the place.
Suddently I noticed an old plastic microscope (with and impressive 1000x zoom) and an old stripped usb webcam.
It was pretty obvious what to do... After adjusting the camera lenses to (very) close focus, an usb microscope was working in no time. You can even remove the IR filter from the webcam and get some IR lights under the microscope to get some awesome images, with the right colorants.

My blood. No kidding. No IR lights here tough.