@elkriverscott,
The deal is this. If you can receive you can broadcast. Ever heard of Radio Silence? So if your in a room with some kind of noise in the background even
if you go silent that noise is still being broadcasted.
You could pick up frequencies with your computer speakers and people could hear you through them as well. With the right setup.
Lot of science. I was looking into that via computer thing as well before. Funny people trying to avoid using the actual radios ( which would cost money ).