You can simply plug in the eye to the RF socket and extend the eye out, you may need to use a small section of Coax cable to move it closer to the tv.
All it does is control the box, nothing more. You still use HDMI for everything else.
In order to keep a a hd picture.. You need to a hdmi splitter and use hdmi leads to use the sound and picture perfect, and just use the RF cable just to change the channel over.
Probably best to disregard this post, as he didn't read yours before he posted and gave out the wrong advice.
proberly pissed writing this. lol