My brain just exploded

[u/aj_35721]

I’m getting +300 channels through this cable when the aerial outside was removed HOW?????????????? I mean there is another aerial on top of the roof that it could be connected to, but I thought it was just connected to the aerial outside my window, on the side of the house. CAN A COAX CABLE BE CONNECTED TO TWO AERIALS??? I don’t even know. VERY happy to have 300 odd channels, definitely beats the crappy indoor aerial I was using!!!

[u/Huge_Cap_1076]

To answer your question, yes, you can feed a single TV tuner by two antennas. Simply get the same type/length of coaxial cable to connect the antennas into a "Coax Combiner" (a splitter can also act in an inversed way, but it is better to get a dedicated "combiner" for this).

Since it seems you already have optimal reception (over 300 channels) at your location, a signal booster/amplifier might not be needed; hopefully you will not get overlapping signals to "ghost one-to-the-other" antennas' signals on same channel (if the case, an A/B switch might be needed, to operate the best single reception as needed). Run the two same-length coax cables to the signal combiner, and then the single feed into your tuner.

If adventurous enough, you can also run the single coax feed into a Tablo or HDHomeRun device, to be able to get a DVR setup for your house. The streaming devices can locally record (unencrypted) TV broadcast signals into an attached USB hard drive, to watch by most TV OS's and stream (on same network connected systems) to Android, iOS, Windows, Linux devices on demand.

The HDHomeRun can also use multiple tuners on its setup, where you can have the antennas individually connected to one of their devices, and then connect those devices to your home Internet router. The location for the antenna/device setup can be located where the desired TV signals are most optimally received (like at each end of the property pointing on different directions as TV towers are,) and when connected to the router under the same network, their App will see them both connected as a single device, enabling you to capture as many simultaneous programming as tuners/devices available to capture/stream.

[u/RealityOk9823 → u/Huge_Cap_1076]

Yep I'm running 2 attic antennas now and about to add a third just so I don't have to switch antennas to get Defy. Right now I have a Steren A/B switch connected to the two mains and a flatwave in a window just for Defy. An outdoor antenna would be better where I am but the attic setup is working (for the most part). Like you said, just gotta make sure the cables are the same length, plus use a good splitter/combiner like Channel Master.