I've actually seen a cable company deploy these in a commercial installation. The Coaxial cable that comes from the pole has a voltage differential on it alrea

I've actually seen a cable company deploy these in a commercial installation. The Coaxial cable that comes from the pole has a voltage differential on it already, 96 Volts, IIRC, and it powers the demarcation device. (which is kinda a modem/voip device breaking out into a phone line or two)