I don’t own a TV but today wanted to watch a hockey game. I’ve got a USB attachable Realtek RTL2832U DVB-T adapter. Assuming you’re running Ubuntu Linux and the DVB-T dongle works, this should do it:
sudo apt-get install w-scan
w_scan -c FI -L > channels.xspf
FI above refers to the country you’re in; use
w_scan -c ? to get a list of available country codes.