Receiving NTSC Analogue TV with GNU Radio and an RTL-SDR
Over on GitHub user kik has uploaded a tutorial and code showing how to decode NTSC analogue TV in GNU Radio and an RTL-SDR. The tutorial is in Japanese, but Google translate should be good enough to understand the text. Kik shows us what GNU radio blocks to use and provides the python code needed to display the images on a simulated scope.
If you just want to receive analogue TV signals, try TVSharp.