It has been a while since my last post and I know that some of you are waiting for some very informative posts about gyroscopes and magnetometers, but today is not that day. I want to talk a wee bit about my life in the past few months, since I joined SeeByte and moved to Edinburgh (As you may recall, I was born and raised in Las Palmas de G.C.).

Even though I haven’t written much in this blog, if you go back about a year ago you will see that I was already working on some interesting UUV projects, so SeeByte seemed like the right place for me, since above all I’m a developer/programmer/software engineer/computer scientist. The work I’m doing is very interesting, but unfortunately I’m not allowed to talk about it, suffice it to say it is related to ROVs, as was my , although the level of complexity is much higher.

Three years ago, in 2009, I came to Edinburgh with my sister and thought it would be a great place to live in, and now that I live here I can certainly agree with my past self. If you come from a hot place, like the Canary Islands, the Scottish weather may not agree with you, but I have to say that I really do like the cold, those of you who know me probably know that already. All right, to be fair I sometimes miss the Sun and the heat.

Aside from my job and my personal life, I have also been dedicating some time to my projects and in doing so I’ve learned quite a lot about electronics. The first of the projects I completed was a GPS datalogger but for that one I will dedicate a full post which is already half written. The rest of the projects are not that interesting but I’m quite proud of two of them, one is a Sound Meter (also known as VU Meter) and the other one is a variable power supply.

The variable power supply uses a few voltage regulators in order to achieve fixed 5v and a variable voltage dependent on the input voltage, which can be anything between 7v and 36v  if I’m not mistaken, and the value of the potentiometer, this voltage can then be set between the input voltage and 1.25v. I also added an LCD voltage meter I bought a while ago from ebay. The end result is a very useful device which I can use to power the rest of my projects with a few standard AA batteries.

The sound meter was just an idea I had to learn about LED matrices and shift registers, but it ended up being a lot of fun. In this project I also included an Attiny85, which is a very small microcontroller similar to the ones you can find on the . In order to program the Attiny, I used the Arduino itself and the Arduino IDE.

The basic idea behind the sound meter is to sample the output of a standard microphone and extract from it some sort of volume level. I didn’t want to spend much time with the programming part of the project so the algorithm I implemented is very simple and it is probably not as good as some others you can find on other VU meters.

Once the volume level has been obtained, the shift register is used in order to activate the necessary rows of the LED matrix. In the following video you can see an example of the sound meter working when it was just a prototype on a breadboard, the code I was using is quite different from the latest version and the result is much nicer now, but I was too lazy to make another video.

I think that’s all I wanted to say for now, on my next post I will talk about the GPS Datalogger. Sorry for those who are waiting for the gyro stuff, but you will have to wait a bit more, spoiler alert, gyros are not very useful on their own.

By the way, I’m very disappointed with Google’s decision of killing Google Reader. Please reconsider Google, the options out there aren’t half as good/simple, and that goes for Google+ as well.