My Third Project: DIY TV-B-Gone Micro

Y'all ready for another political post? Tough! Because I'm back to gadgeteering. After the resounding success of my first two projects (check them out below if you haven't seen them), I figured it was time to start something new. Take the time now to skim past the old to see the new.

The Useless Machine

Some Really Awesome Water Barrels: A great way to save water

My understanding of circuity is basically nil. I know how to solder and I'm pretty good at following instructions, but at this point, I don't have a clue about how these things work. This essentially means that I am still somewhat limited when it comes to picking new electronics and DIY projects. But I knew that I had a winner when I read through this lifehacker post. The project looked doable, but it would be a whole new level of soldering and computer programming.

The goal of the project? (Question)

To build a tiny device that serves as a universal off switch for televisions. (Answer)

When might you use it? (Question)

Not really sure. But it's neat. I guess you could use it if you are at a restaurant and an annoying TV is blaring in the background that nobody is watching. (Answer)

The very detailed and helpful instructions for this project were found at instructables.com.

The best, and most challenging, part of this project was that it involved two parts. The final "tv-b-gone" device utilizes an Attiny 85v micro controller, programmed with the set of TV codes.

To program the micro controller, I actually needed to build a USBtinyISP AVR Programmer and SPI Interface, available as a kit from ladyada.net. The kit includes all of the parts, including the circuit board, but you need to solder it all together. Below is a picture of my soldering rig. Check out the cool circuit board holder that I purchased. That holder, along with the "third-hand" that I purchased later were tremendous aids in this project. I, personally, don't have 3 hands, and I don't believe that I could have done things as nicely without them.

Here is a close up of the board after installing some of the components.


And the final result:

After building the programmer and installing the USB drivers, I had to wait for a week until the micro-controller and the rest of the parts for the tv-b-gone arrived in the mail. I did plug the programmer into my controller, and, after my computer recognized it, I installed the drivers and the AVRDude program necessary for programming the chip. I cannot tell you how awesome it was to plug this home build device into my computer and get the initial impression that it worked!

Still, the next step would be difficult. In the picture below, note the "breadboard" with all of the wires shooting out of it. Because I don't have a board built (yet) to house the micro-controller that I want to program, I needed to build a temporary setup using a breadboard. Each prong on the micro controller needs to attach itself to a specific wire/spot on the programmer. I followed some guides and schematics, but the process was still difficult.


After a few incorrect setups, I did get all of the wires in the correct spot, and I followed the directions to program the fuses and the actual chip! I'll admit again that this was an amazingly dorky moment for me. I was very pleased that it worked.

With the chip programmed, it was time to start building the final TV destroyer.

Above is an early picture of the project, and below is the final result. It doesn't look like much, but it works!



My first test was when I put the battery in and the thing didn't start smoking and blow up in my hand. Success.

Next, I went out to the living room and tried it out on my parent's television. At first, I just pushed the button in and let it out. Nothing happened. But, then I held it in for a second, and the TV turned off. Success.

With the initial tests over with, I needed something better. I was sort of afraid to try it out at Best Buy, so I went to KMart, where I could be reasonably certain that nobody would be around to get mad at me. (I was right, nobody was even in the electronics area).

I went to the TV section and stood there, holding in the button. One by one, the TVs starting shutting down. To be fair, they didn't all turn off. But I think that about 80% of them did.

Another project done. I have a second set of parts for this project, so I will probably build another one before everything is said and done. I am not sure, yet, if I will do anything differently. Because of the lack of a case, the device is fragile. I have seen a few encased in hot glue from a glue gun. I may try that.

I am also unsure of what my next project will be. Now that I have this AVR programming board, I want to make something neat. It may be this.