Identify

You can't win the war if you don't know your enemy, right. Well then how do you expect to descramble your cable without knowing how it's scrambled. Just compare the images below to your scrambled stations to find out how the channels are scrambled.

Sync Suppression

syncsup.jpg

Sync Suppression is easily identified by the "wavy bar" that wiggles through the picture. This bar is actually the horizontal blanking interval.

A close look at the bar, will show 4 bands (white,black,colored,white). The black band is the sync (or lack of it) and the colored one is the color burst. This information is normally hidden behind the right edge of the picture tube. 

Video Inversion
Video Inversion involves more than just inverting all the video information. The active video (the stuff that lies between the two sync intervals) is all that gets inverted. The sync and color information remain at their proper polarity. This causes the color burst to be phase shifted 180 degrees, in respect to the chroma. The end result is a negative image (dark = light) with a color shift (ie: yellow = blue). 

This method is usually coupled with sync suppression.

SSAVI Suppression

ssavi.jpg
The SSAVI system is easily identified by the "dotted" line that appears near the top of the screen. These "dots" are actually the authorization data contained on lines 10-13 of the vertical interval.