DIY HeadPhone Amplilfier

Background

I have always been interested in building something like this since my second year at university. But apart from repairing small things like re-soldering a power cord, my adventures down this alley have normally resulted in failure. The most memorable was my attempt at building an FM transmitter from an internet schematic (I can’t even tell what was wrong with this, it just did not work). Recently though, I was encouraged by my “success” in replacing the bulb in my flashlight with LEDs. I put success in quotes because there was no notable increase in the illumination from the torch but it was at least not worse than it was before. So I count it “success”…….. 🙂

This project came back to the forefront a few months ago when I decided to learn the bass guitar but as you might expect, this was not kind on the ears of the people who had to listen while I slowly and painfully attempted to get to the skill level of the likes of Fred Hammond. So I thought this was a great opportunity to convince my wife why it was necessary for me to get a headphone amplifier 😉

Assembly

And so the journey begins. I did quite a bit of research on my options (to build or to buy??). I ended up striking the middle ground by buying this kit off eBay and try to recreate my recent success in the field of DIY electronics. It basically contains a printed circuit board and all the parts needed (that was another reason I got a kit as opposed to buying individual parts. It is hard to get exact parts locally and as a beginner it is not easy to substitute parts). Anyway, 6 weeks later the package arrived and I dove into the construction.

The first thing I noticed was that the schematic referred to a  pair of capacitors which were not in the package.

Kit as shown on eBay....notice the 2 blue capacitors beside the board?

I decided to put it together anyway even though all internet references to the project showed that a couple of capacitors should be in the mix.

Other than that the process was mostly without event. But it was a huge learning experience with regards to soldering. For instance, I don’t know the differences between the type of solders (need to read up on that shortly) but the one that was included in the kit had a tendency to “blot up” more than the one I had. It was as if it was harder to melt and I had to be making a special effort to get clean, neat solder-points. When I started using the one I had before, as soon as I touched it with the soldering iron it just melted and it was like it formed the perfect shape all by itself (as opposed to spreading out all over the board). Also, the opamp chip should be removed from socket before the socket is soldered….it will burn :-D.

Pics of the process and the finished product can be seen here.

I carved a housing for it out of an extra power brick which I had lying around in a box. This was quite a challenge though because I didn’t have any of  the tools to make the holes or properly mark out the spots to be cut. As you can see it wasn’t a total disaster.

Conclusion

Apparently the capacitors weren’t needed as the completed amp worked perfectly without it. As a-matter-of-fact when I added some capacitors of values which some other sites were recommending for their projects, it sounded significantly weaker.

So, as is, the amplifier sounds loud and clear with even my cheap/free BB earbuds and does enough to let me hear the guitar without disturbing anyone else. Overall this experience is worth far more than the $25 I spent on this project.

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Use the Windows Key for the “Start” Menu in Ubuntu Linux – How-To Geek

Ubuntu has a dropdown menu at the top of the screen to launch applications, which is very similar to the way Windows has the start menu at the bottom of the screen. If you are a windows user new to Ubuntu, you may prefer to have the windows key launch the applications menu. Thankfully this is an easy thing to do in Ubuntu.

Go to the System \ Preferences \ Keyboard Shortcuts menu item:

Scroll down till you see the “Show the panel menu” item. Click in the Shortcut column, and when it changes to “New accelerator…”, hit the Windows Key. Click the close button. You’re done!

Now when you hit the windows key, the application menu will pop up. If you hit the right arrow key, you can go to the Places or System menu as well.

via Use the Windows Key for the “Start” Menu in Ubuntu Linux – How-To Geek.

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How to Tell What Version of Ubuntu You Are Running

Telling what version of Ubuntu you are running is extremely easy. You would commonly use this command to figure out if you are running Edgy after you upgraded from Dapper.

cat /etc/issue

Ubuntu edgy (development branch)

Note that the version numbers might change over time. I’m running the beta version so that’s what shows up when I run that command. Either way, it should be clear that you are running Edgy.

via How to Tell What Version of Ubuntu You Are Running – How-To Geek.

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Change or Reset Windows Password from a Ubuntu Live CD – How-To Geek

If you can’t log in even after trying your twelve passwords, or you’ve inherited a computer complete with password-protected profiles, worry not – you don’t have to do a fresh install of Windows. We’ll show you how to change or reset your Windows password from a Ubuntu Live CD.

This method works for all of the NT-based version of Windows – anything from Windows 2000 and later, basically. And yes, that includes Windows 7. Continue reading

Clean Up the New Ubuntu Grub2 Boot Menu – How-To Geek

Ubuntu adopted the new version of the Grub boot manager in version 9.10, getting rid of the old problematic menu.lst. Today we look at how to change the boot menu options in Grub2.

Grub2 is a step forward in a lot of ways, and most of the annoying menu.lst issues from the past are gone. Still, if you’re not vigilant with removing old versions of the kernel, the boot list can still end up being longer than it needs to be.

sshot-1

Note: You may have to hold the SHIFT button on your keyboard while booting up to get this menu to show. If only one operating system is installed on your computer, it may load it automatically without displaying this menu.

Remove Old Kernel Entries

The most common clean up task for the boot menu is to remove old kernel versions lying around on your machine. Continue reading

Linux on the iPhone: iPhone 3G binaries!

I wrote up a how-to for PC World on how to put Android on the iPhone 3G and the iPhone 2G and it went up today. I wanted to be there to tweet about it when it went up, but I’ve been keeping really strange hours lately and I wasn’t awake for it when it went up.

But here are the binaries (for iPhone 3G, and for iPhone 2G), graciously hosted by PC World!

Please read the how-to that I wrote for PC World to on installing it. The steps are basically the same as before, except you can put the firmware in a directory on the iPhone OS data partition. This means that you don’t have to modify the ext2 partition as before.

One thing I didn’t mention is that you could perform the installation on OS X without a Linux VM if you recompile loadibec and oibc. Otherwise, the directions are the same.

via Linux on the iPhone: iPhone 3G binaries!.

Hello world!

This is where I will host my monologue, since I doubt anybody will ever read or better yet comment on what I write.My interest mainly comprise of the following:

  • computers and related accessories(smart phones)
  • DIY electronics
  • music
  • TV/Movies
  • … and the list goes on in that circle

So that’s the type of stuff you will find here.