Sorry, no. You need something like a Tablo TV box or HDHomeRun tuner to watch OTA on a Roku device that isn't a TV. Even then, it doesn't get incorporated into what Roku calls "Live TV". They each have their own Roku app and right now a lot of people are having a problem with Tablo after the Roku software update to 14.04. Oddly enough, mine still works. Obviously, the free option is to connect an antenna to the TV and use its tuner.
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