What sort of adapter are you referring to? Roku devices connect to any HDMI port on a modern TV.
I know nothing about Proscan TVs. If it is one that had an MHL port (looks identical to an HDMI port but differs electrically), then you can't use a Roku on it. Look at the port labeling carefully. If it says MHL, it's a no-go. If it's labeled MHL/HDMI or just HDMI, it should work. Yes, the Roku Stick must be connected to a power source. While many TVs have USB ports on them, many times they don't provide enough power for a Roku player. You should use the power cube that came with the Roku.
You don't use any channel on the TV. You need to select the input that you have connected the Roku to. If the TV has more than one HDMI port, they should be labeled with the port number. Press the Input button on the TV remote and find the matching number.
Has this Roku been previously set up, or is it new fresh out of the box?
Dan
Roku Community Streaming Expert
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