[Tech Minds] shows RTL-SDR Scanner on Linux to record up to 20 ... you could probably run this on a small computer on the network and then access it at your leisure from another computer.

One of the best ways to learn about radios is to build your own, even in the age of cheap SDR dongles. [Aniss Oulhaci] demonstrates this with a simple HF SDR receiver built on a breadboard.