Making a Siemens C55 Data Cable

Hi! Recently I've been developing a GSM access control system for eLab Hackerspace using an old Siemens C55 cell phone and, as such, I needed a data cable to connect it to a PIC microcontroller. I searched on ebay for one but it turned out that they were a little expensive and I began thinking about a way to make myself a data cable.

(Click the photo for better resolution in Picasa Photostream)

Luckily, after searching for a while in my "old power supplies box" (a box where I store all the old phone chargers and power supplies), I found two chargers for old Siemens phones, having the connector that I needed. However, I quickly realized that they only had the VCC and GND pins and I needed a connector with Tx and Rx pins too.

Since I had two chargers I decided to try to modify the connector of one of them to add two more pins and it worked perfectly! :)

Read more »

Lab tip for power connectors

Hi there! Today I'll show you a simple but very useful tip for your hacking sessions in your home lab or local maker/hackerspace.

Probably sometimes you want to power some device from your laptop's USB or phone charger, but the device has a DC barrel power connector and there you go and make a USB A to DC barrel connector. Then, in some other day you actually need the same thing but with a micro USB, or a mini USB, or a USB B, or a thinner barrel connector, or a larger connector, or alligator clips, or a longer cable, or a shorter one, and so on... The problem is that after some time you'll end up with lots of connector converter cables and you'll still find yourself needing a different connector converter cable. Well, I'm going to share with you a simple solution to avoid making lots and lots of cables.

(Click the photo for better resolution in Picasa Photostream)

Read more »

Record Audio playing in your computer

Hi! In this post I'm going to explain you one of those things that the music industry doesn't want you to know: how to record audio playing in your computer. :)

Some years ago, back in the days when I was still using Micro$oft Windows XP, I remember that in the sound properties there was an option named "stereo mix" that would allow you to do record the audio being sent to the output of your sound card. However, from what I've read some time ago, that useful option has vanished from the sound controls in more recent versions of Micro$oft Windows.

When I heard about it I started wondering why would they remove a useful feature from the audio options. I googled about it and the history is that the music industry made some pressure next to sound card manufacturers, Micro$oft and Apple so that they would drop that feature in hardware and software, so that people wouldn't be able to copy music. If the history is true or false, I do not now, but, honestly, it wouldn't surprise me and certainly is a kind of measure that fits within the spirit of SOPA, PIPA, ACTA, etc. : limiting the freedom of people to get money at all cost.

However, using linux gives you back that freedom. Moreover, using the audio-recorder application you can do it in an even better way! :)

(Click the photo for better resolution in Picasa Photostream)

The audio-recorder application allows you to record audio being played by any program of your choice, instead of the final sound card output mix. To install it you can download the appropriate package for your Ubuntu version and computer architecture (32- or 64-bit) here.

Read more »

Cheap Ball Casters for Small Robots

Hello everyone! :) In the title of this blog I mention that it is also about robotics. However, and to be honest, I've realized that I haven't posted much stuff about it. I hope to fix that in the following posts since recently I've finally finished some robot projects that I have been doing in the past months. Unfortunately I can't publish them yet. Maybe in a month or two :) Anyway, I'll start with a simple post regarding a simple but very useful part for small robots: ball casters!

You can buy ball casters from several robotics shops online and they're not the most expensive thing on earth. However, there are other options that can be cheaper and will save you from the waiting until you receive the ball casters that you may order from shops online. Some of the options fit in the spirit of Green Robotics, which is the idea of reusing and recycling everyday things to make robots. I'm going to show you three options that may suit your needs :) .

(Click the photo for better resolution in Picasa Photostream)

I'll start with the option that I think to be the best of the three that I'm going to talk about. See the shiny metal balls stuck in a white plastic piece? They look really good, don't they? :)

Read more »

How to Install LibreOffice 4.0 in Ubuntu 12.04

Hi there! I don't know if you've heard about it but this week we had some great news for the open source community and Linux: LibreOffice 4.0 has just been released. :) I'm not going to describe all the new features and improvements since you'll get a better glance at them by visiting the release notes. I'll just point out four of them which I think to be the most significant:

(Click the photo for better resolution in Picasa Photostream)

1. Better interoperability - Interoperability with other file formats is a very important feature for any user and a critical one for enterprise users;
2. Remote control Android app for presentations - a month ago I was just discussing with my brother how this would be cool to do and gladly the LibreOffice development team made it a reality. Now you can control and view the presentations simultaneously in your Android phone or tablet;
3. Preetier User Interface - it now supports Firefox Themes. Now you can customize the looks of your Libreoffice instalation;
4. Better Performance - faster, faster and... did I already say faster?

Read more »