With many hackers out there realizing how much you can do with a few RF blocks connected to a computer, it’s no surprise software defined radio would make a showing in the semifinalists for The Hackaday Prize. [Michael]’s project is the PortableSDR, a small, self-contained unit that handles just about everything below 30MHz. No, [Michael] isn’t dealing with gigahertz accessible with fancier SDRs, but that’s not the point: PortableSDR is meant to do everything – vector analysis, a neat waterfall display, transmit and receive – in a small, portable package you can take anywhere. It’s also fairly cheap to build, and of course completely open source.

This isn’t [Michael]’s first rodeo; he’s built a number of equally cool projects before. He was kind enough to send in a short bio, available below.

Just one? Obviously radio and electronics are big. Hackaday is my favorite site, if that tells you anything.

I enjoy all sorts of outdoor activities, backpacking, rock-climbing and, most recently, paragliding.

I’ve been interested in Asian culture and languages for years. I studied Japanese in high school and college and I was able to serve as a missionary for two years in Taiwan where I picked up Mandarin.

Other than my wife, it would probably be learning and making, experiencing new things. Before I could build things, I would draw a lot, I’d create people, places and things that only existed on paper.

Printers are a pretty good one. Maybe computers in general. Sometimes I wish software was a thing that could be smashed… ugh.

I was a die-hard Mac user as a kid and I still think it’s very well designed and usable, but pretty much everything I want to do requires Windows (7 or Server editions please) so that’s what I find myself using most. I play with Linux here and there and I love what it can do, but haven’t really gotten comfortable with it, everything seems to take so much work.

Oscilloscopes. Just picked up a Rigol DS1074Z and I love it (get the signal gen, it’s worth it!) That said, if Tektronics wants to sponsor me, I’d gladly accept a MDO3/4000.

Also, Current limited bench supplies have saved my bacon a number of times….. also flux pens. And if you can swing it, a binocular microscope, I don’t know how I lived without it.

I’m really enjoying the STM32 microcontrollers. The F4 in the PortableSDR is a beast! 180Mhz, FPU, lots of memory, and ten each of every peripheral you could ever want. They are so flexible too. On the AVR-Arduino/PICs, your GPIO are digital or analog, sometimes you have a built in pull up resistor. The STM32s (I imagine a lot of this applies to other ARMs as well) have pull ups and pull downs, and open-drain, various drive levels for every GPIO. It has DACs built in, etc. I was using an AVR for something once and I was going to be using TTL serial, but it was inverted, so I had to add some circuitry to flip it, don’t need to on the STM32s it has that ability built in.

C. (Also C++/C#/Java) No real reason, it’s just what I know and am comfortable with (not that I’m particularly good at any of them) also runs on anything!

I have a secret one (not helpful, I know.) I hope to Kickstart at some point.I am part way into a connect home security/home automation system that includes thermostat control, and power consumption measurement. The coolest part, though, is that is uses the Portal Turret voices (open a door and you hear, “Hello? Who’s there?” walk in front of the motion sensor and get, “There you are!”)

I’d been interested in Software Defined Radio since I first heard about it a few years ago (this article in particular) and wanted to build my own. As I learned more and more about electronics and microcontrollers in particular, I thought I could combine SDR with my interest in the outdoors.

Lots of stuff! Here are a few: To the DSP guys, how do I build an arbitrary filter for FFT convolution with a known kernel length? The way I am doing it now seems to be wrapping around even though I have padded my samples. I’m probably making tons of mistakes… RF guys, I’d love a hand designing an efficient RF amp to get up in to the 1-5 what range, that is small and can run off 3 volts. To the Hams that are into morse code, what hand do you use, what angle do you position your key at, I’m thinking 45 degrees? Ever tried capacitive keyers, what did you think? There is a ton of brain power in the Hackaday community, so I hope people will tear into the PortableSDR and help me make it better. I look forward to (hopefully constructive) feedback!

Several. I thought the GPS Clock was very polished. I wouldn’t mind building myself one. And the microwave lost PLA project?! Hybrid Jetski, I’ll take one. Cardboard hovercraft. To name a few. Several of the projects I like did make it to the semifinals.

I have been having a lot of fun with the contest and it’s been inspiring to see all the cool things other people have come up with. Also, I really appreciate all the positive support I’ve received from people as I’ve worked on this project. A few have built their own already, and someone even posted about my project on reddit. Thanks everyone!