This year, my place of employment gave me an end of year bonus, and it was substantial. It was, in fact, the largest bonus I have ever received. So, I went a little nuts buying stuff, mostly electronics. I got a couple of things I've wanted to get for a while. An SDR receiver dongle that works for HF, and a device I've wanted to buy for a while, which is a HackRF One. A HackRF One is a software-defined transceiver that covers all the frequencies from 1 MHz (and possibly lower) up to 6000 MHz.
gnuradio
I've been working on an SDR (Software Defined Radio) receiver that I can control via computer so I can use my TV receiver dongle to work linear transponder satellites. It hasn't work or, rather, has kind of worked strangely so last night I took it apart, metaphorically, and experimented with locally-generated signals so I could try to figure out what was going on. Having identified the errors, corrected those errors, and tested the correction, I can now explain how to make one of those things that works. The receiver part, anyway.
While I'm waiting for new boards to come in for the Arduino-based memory keyer and while I'm waiting for NC4L to get my money order so he can ship my FT-102 back, I'm working on getting back on the satellites. I've decided to try my hand at the linear-transponder satellites. I've watched guys like Andy (W5ACM) operate linear satellites with nothing more than an FT-847 and some well-practiced skills, but I don't have any FT-847 equivalent, and the all-mode radio that I do have is computer-controllable so I can run computer-controlled.
Like I put in my Links Page, Owen Morgan has an article on using $20 TV dongle to do software-defined radio.