A diplexer is a device that combines radio frequency inputs from two or more radio transmitters into a single output, or, when used in the opposite direction, divides a single RF input into two or more outputs based on frequency. Depending on how it is used, a diplexer may be called a combiner or splitter.

How does a splitter combiner work?

The difference is that a splitter takes in one signal and makes two out, while a diplexer or combiner takes in two signals and makes one out. Splitters are commonly used for adding a second television to an existing cable. ... You're sending half as much signal through each line when you split out the signal.