Hey so what you're talking about are the SMPTE Color bars. Afaik, the picture that Silenos posted is a PAL sign-off test pattern, PM5544. I actually use it myself to test colours and geometry on a CRT. NTSC countries used test patterns such as the SMPTE color bars or the Indian test pattern (for the sacred land of freedom units) when signing off. What you have to keep in mind is that when you see a test pattern such as the color bars, there is a signal, it is just sending the test pattern picture to the TV. When there truly is no signal, you'll see static. Like this: