Adapting coaxial cable for a computer or video network is surprisingly easy, using the right adaptors. Since there is no way to make a direct-wired coax to Ethernet cable, a converter and baluns are required to internally maintain the right impedance, while transmitting the signal over longer distances. These adaptors convert the coaxial signals to Ethernet, where the high bandwidth easily carries the dense data from point to point. This leverages the Ethernet cable running through the walls, connecting devices that rely on coax.
Screw the coaxial cable from the router to the coax to Ethernet adaptor.
Click the Ethernet cable's RJ45 connector into the "OUTPUT" side of the adaptor.
Break out the signal travelling over the Ethernet cable to the computer laptop. Snap the RJ45 connector into the balun. Screw the coaxial cable to the other end of the balun to the modem or other device.
Plug the adaptor into AC power, as needed.