This is posted under "Transmitters" because I consider an online radio server to be a true form of Part 15 transmitter, look at all the Part 15 Notices on the routers, motherboards, soundcards, and all, and I'm talking now about my radio servers.
It is even possible to have a backup transmitter (server) which came in handy when I installed the new version of Icecast Server, V 2.5 beta, requiring a shut-down of V 2.4.1.
To avoid listener down-time I ran a Shoutcast Server matching the Icecast specs, 64kbps, 22.05kHz, stereo.
This was lucky because the changeover took two days because of my slow success in getting the new Icecast software to start. Once it did start I ceremoniously ran both servers for a day before shutting down the Shoutcast Backup Sever.
Online streaming is antenna free!!