Terminators for 75-ohm lines

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A 75-ohm transmission line must end in a load equal to 75 ohms or much of the signal will be reflected backwards, possibly getting retransmitted out the antenna. Signals can literally bounce back and forth inside transmission lines. All TVs and amplifiers have 75-ohm inputs, so normally there is no problem.

If you use a splitter but forget to connect one output to anything, some of the signal will be reflected back towards the antenna. Depending on the frequency, the signal power lost this way can exceed the power the unused leg would have consumed. Viewers of the connected TV might discover some stations seem to be missing. The reflected signals can increase the likelihood that the amplifiers will overload. These problems can be insignificant, or they can be more confusing than significant. Getting 75-ohm terminators and connecting them to the unused outputs of the splitter will stop the reflections.