“Algorithmic symphonies from one line of code” meets my R-2R DIY 8bit DAC

Posted by on 2013/03/02 No comments

Last year (2012) I found this cool article: http://countercomplex.blogspot.com/2011/10/algorithmic-symphonies-from-one-line-of.html It shows how you can create “music” using simple bit operators like >>, |, &, and ^ on a single line of code.

In the comments section I found that somebody already had ported (sorry but the link is no longer available) the experiment to run on the Arduino. It uses the PWM square waves to generate the sound. I think they sound OK and requires no extra hardware. But one problem with that approach is that the frequency is not 8 kHz as on the videos on the original post, so the the result is a little bit different.

I have laying around an R-2R 8bit DAC (Digital to Analog Converter) that I built some time ago watching Collin Cunningham lesson. I had never tested it before. Well, actually I tested it using a multimeter and that was pretty boring but nothing besides that.

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Polarity Inversion

Posted by on 2012/09/09 No comments

Recently I received two mini guitar amplifiers that I had ordered some time ago. The power supply is drown from an internal 9V battery or from an external 9V ~ 12V power supply which is not included. The problem is that its input power connector has the polarity inverted related to all power supplies that I have.

The solution? A simple “polarity inverter” like the one that you see on the picture below.

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Comments are back

Posted by on 2012/07/20 No comments

Sorry for the delay. And also sorry for the reCaptcha. I know this is very annoying but I could not find a better solution.

Comments disabled

Posted by on 2012/06/23 No comments

Sorry about this. But I have received a lot of spam recently. I will enable the comments back as soon as I deploy an anti-spam solution.

Etching. Level Up

Posted by on 2012/06/07 1 comment

On my previous post about etching I showed you my first steps. What I really didn’t like about the process was that after the toner transfer phase the way to remove the paper from the PCB was by submersing it in water and then:

  • Use a tooth brush to gently remove the parts of the glossy that should have been removed but are still stuck to the paper (between the tracks). This is very boring and time consuming!

I will show you a modification of the process that has been given me good results and there is no need for water at all:

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Etching. My First Steps

Posted by on 2012/05/06 2 comments

At the beginning of this year (2012) I took a course on PCB etching at my local “Aldeia Coworking“. I was totally new to this skill and we etched a version of the Atari Punk Console that you can see below.

Several weeks later after spending some time learning eagle cad using these good tutorials on YouTube I was ready to etch my first all-by-my-self board.

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Game Clock

Posted by on 2012/04/07 15 comments

I wanted to buy a game clock, but I wasn’t able to find one here at the local stores. Last year, after several weeks learning and playing with an Arduino Duemilanove I realized that a game clock would be a great project.

At my office there are several people who play chess but they usually take too long to play. I thought that a time constrained match would spice up the game, specially for the spectators :)

Sometimes I play go with my friends using a real goban and sometimes I play online at KGS or Panda Net. So I was already familiar with the Byo Yomi and Canadian Byo Yomi time controls.

I jumped to wikipedia and found this page with information about different ways of counting time in board games. My idea was to build a game clock with the most commons time controls used in chess and go.

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About this

Posted by on 2011/10/25 No comments

Hi, I’m new to electronics. I plan to put here things such as DIY, programming, arduino and others. Stay tuned.