Something that I find nice about hacker spaces is the diversity of interests that you find when visiting them. This trait was evident during my last roadshow stop with a visit to HacDC. Every other Wednesday, HacDC runs its Amateur Radio Club night, which is the event at which I spoke about the DARPA Bay Area SDR Hackfest as well as what software-defined radio means and the capabilities it enables. The backgrounds of everyone there were all technical, but in many different areas, and even the amateur radio operators in the room had various backgrounds with radio and software radio technology. Unlike my other Roadshow talks, in this one I actually took a step back to go over the fundamentals of sampling theory and frequency domain representation. It was a useful exercise to show how much we can experiment with these tools and learn from them, and I had the sense that what I was showing connected with a lot of people. I had some great one-on-one discussions after the talk. My hope is that the talk generated enough interest in the field of software radio that some of the attendees would want to participate in the hackfest this November.