are you trying to get channels over the air? If so, go here http://www.antennaweb.org/aw/welcome.aspx and plug in your location info to determine what channels are available in your area and what sort of antenna you might need to receive them.....it will also indicate the direction of the closest signals so you know which way to point your antenna.
If you are not talking about over the air, I am confused as to what you are asking.
For anyone who hasn't thrown out their UMC 19" Freeview television because of the 'No signal' status. Go into 1st time installation & change system settings from PAL to AUTO. Hey presto it's sorted. I have had experts looking at my TV for months since I moved & they couldn't sort it, so tried myself. Good luck.x