Mostly playing around with high spectral efficiency digital modulation techniques like PSK/QAM and OFDM using GNU Radio. Trying to shovel as much data as I can between two links with as little power as possible. I'd like to experiment with below-the-noise-floor communication, but haven't gotten there yet.

It's sort of silly, because you can do all of this in simulation, but it's more fun with real hardware. Eventually I'd like to be able to build a (solar?) drone with a radio system resembling a cell tower and do ground-drone-ground relay experiments, but I'm extremely not there yet.

I also wanted something that could transmit after I got a ham radio license (out of boredom during the pandemic, shortly after they started doing testing online), but haven't really used it that much, as I don't really have a good antenna set up. For data experiments, a wire or a PCB trace works well enough.

I also do a lot of embedded Wi-Fi / Bluetooth stuff at work and would like to use this for packet captures, but haven't needed to yet. It's completely overkill for something like that though.