Cable Connection Novice

So I know very little about cable connections. I bought a brand new Samsung HDTV flat screen and put it in my basement. The problem is that I couldn't get the TV to recognize the signal from the cable TV (coaxial?) cable. I eventually connected the TV to the digital cable box with component cables. I had an old, old tv/vcr from college that I used in my bedroom that worked fine when connected to the cable wire. However, I just bought a new LG flatscreen for that room. I am having the same problem with the TV saying there is no signal from the cable. Problem is there is no cablebox in the bedroom so the cable connection is the only way to get a signal to the TV. Is the cable signal just too weak for these TV's? Would an amplifier work? I also want to mount the TV in the basement and would rather use a different cable than the component cables to do it. Anyone familiar with these issues? Thanks!

What's the model number of your new Samsung? Did you read the manual and follow all of the directions for setting up the cable connection?

Read your instruction manual.
Is the cable connected to the proper input; have you selected the proper input?
Is the cable in the basement "live" or possibly just hanging somewhere?

the upstairs wire is definitely live, as I had a old TV plugged into it. The downstairs wire was left from the former owners and could be just hanging. Both TVs are set to the proper inputs. The cable guy actually set up the one doenstairs. The model # for the LG is 19LH20.

Did you read the manual?

The cable guy actually set up the one doenstairs.
So are you saying that the cable guy set it up and then left with it not working? That's odd.