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Level 7

Roku Ultra affects my OTA antenna signal!! Why?!

Hey Guys,

I am really baffled at something I just discovered and am hoping you can help me understand what is going on.

My TV is an LG OLED B8.

First off, I use a Mohu Antenna to watch live OTA TV and a Roku Ultra for internet TV/movies via ethernet cable. I do not use any of the TV built-in internet capabilities - in other words, no wi-fi and no ethernet directly to the TV. The only cables I have plugged into the TV are the coaxial for the antenna, an HDMI for the Roku Ultra, and an HMDI for my dvd player.

What I have discovered is that while I am in Antenna/Coax mode watching OTA TV, if I unplug the Roku's ethernet cable from the Roku unit, the antenna signal for certain channels becomes instantly weak and or, for some channels (which normally have very strong signals), completely gone. Same thing happens if I unplug the HDMI cable from the Roku unit. As long as both of those cables are plugged into the Roku unit, my OTA antenna signal is nice and strong for all channels. In fact, if I unplug the HDMI cable and then just lightly touch the cable to the Roku unit's HDMI port (but not actually plug it into the port), the antenna signal suddenly gets stronger.

If I unplug the power cable from the Roku unit, that makes no difference for the antenna signal. However, even with the Roku unit's power cable unplugged, the same issue still exists. In other words, even without power going to the Roku unit, both the ethernet and HDMI cables still need to be plugged into the Roku unit or else the OTA antenna signals are really bad.

What in the world is going on here?? Why would unplugging the Roku unit's ethernet cable or HDMI cable affect my OTA antenna signal??


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Level 18

Re: Roku Ultra affects my OTA antenna signal!! Why?!

The damnest things can affect OTA. Foil will do interesting things.

I have a MOHU leaf as well but havnt used it for quite awhile.

There are a lot of variables I think like 'Ground Looping' and static this and that.

Who knows at least you can solve your own problem.

---A problem clearly stated is a problem half solved---.