Are you talking about TV signal strength? My version of Media Center can do that.
Using the menus go to Tasks/Settings, then "TV", then select "TV Signal". On my system I have "Digital Tuner Diagnostics" as a option here and by drilling down into this screen I can eventually get to a screen that tells me all sorts of info. My signal/noise ratio is 34 dB (sometimes 35) and my Signal Level is 36 dBmV. I'm not sure if those are good values but my picture looks fine to me.
Hope this helps.