Addressable systems work with a cable box or addressable tap where the cable company has an ID address for each customer and can turn programming on and off from a central control point by several methods of jamming, filtering or scrambling the signal.
Filters come in two varieties that do basically the same thing. There are positive filters that are a fine tuned filter that remove a jamming pulse placed between the video and audio carriers. There is a negative filter that removes or blocks the entire channel or entire band widths.
Hope this helps.
