It may look like a splitter, but a diplexer is much more complex than that. Splitters are simple: You have a single input and multiple outputs that transmit the signal. A diplexer works with radio frequency coaxial cables and is reversible. It may split one input into two output signals, or it can combine two inputs into a single output. When used to combine two signals, the diplexer keeps both signals independent of each other without combining power level. This means that one diplexer can combine two signals, and another can separate the signals at the other end of the cable. They are often used to send satellite and cable signals without the cost of laying two separate cables. You can find loose diplexers as well as wall-mount diplexers on eBay. The latter have face plates that match your electrical outlets and help avoid messy cables left laying out. Buy a diplexer to pull multiple signals from one coaxial cable and avoid the bother of tangled cables.