I have been intrigued by software defined radio (SDR) for some time. The basic premise is that many of the components of a radio that were traditionally implemented in hardware, can now be done in software. This includes filters, mixers, amplifiers, modulators, etc.
RTL-SDR came about when someone discovered that with a little software, a cheap USB TV dongle can be used for wider SDR, and I had to see this in action. After a little research, I decided to buy a Terratec T-Stick Plus (sheesh, the price has risen dramatically) because of the chip used. This particular dongle has an Elonics E400o chipset, supposedly one of the better choices.
The software was a bit of a beast to set up (first I tried on OS X, big mistake) but I finally have something going. I haven’t fiddled with it much yet, but I can’t wait to try and put that RF school-learning to some proper use.
This week I took a metal clay class at the Dallas Makerspace. Metal clay is basically around 90% of the metal you desire (bronze, copper and silver are all examples) and 10% organic binder and some water. You shape the metal clay into whatever shape or size you want (with a few limitations), let it dry and then fire the clay.
Firing the copper and bronze clay requires a kiln to maintain a temperature for a longer period of time, but the neat thing about the silver clay we were using was that it could be fired with a simple butane torch.
The class at the makerspace was taught by Jenny Vestal, who also teaches an online course on the subject on Craftsy.com. We made some simple charms to begin with, and we were given extensive instructions for further projects. Here are the earrings I made!
I have a few fun ideas for some electrical engineering themed pieces. Transistor symbol keychain anyone??
Yesterday I attended a workshop at the Dallas Makerspace on using the Arduino as an ISP for smaller microcontrollers. As most of you know, there can be many advantages to using a smaller microcontroller instead of a full Arduino or Pi or whatever including size, battery life, cost, etc.
We essentially followed the same directions listed here on High-Low Tech to program an ATtiny85. It was amazingly easy to use the Arduino to program the 85s. Those little beauties are under a dollar and can do quite a bit! So far I’ve gotten the ATtiny85 to blink not one, but TWO LEDs. I’m really interested in trying out the slightly larger ATtiny84 coupled with a little 433 mhz radio module to make a super cheap wireless sensor system. Hopefully you’ll see that soon! Thanks to Ralph for teaching the class.
I’m kicking myself for forgetting to take pictures, because last weekend I had the pleasure of volunteering at a high school robotics competition that was being held at my university. The competition was through Lego FTC (First Tech Challenge). I was brand new to this whole world of competitive robotics but I had a great time volunteering.
There are two parts of the competition, building the robot to perform a number of tasks and then another component where the kids give a presentation to a panel of judges about their challenge. I got to judge these presentations and I have to say that I’m so impressed with our next generation of engineers. These kids were from all over the local area, from very rural areas to the most urban schools. They all had unique ideas and perspectives and I was so fascinated with how the program helped them develop incredible STEM skills as well as learning to present and document their work and ideas.
I hope to be able to volunteer again, and the next time I promise to take pictures!