   == Half finished? == This article like many Wikipedia seems to be pretty good technically at least in some ways but there seems to be a lot missing. What this article really needs is a proper TV engineer to write at least a section for it, I could be persuaded to do this but I would have to do a lot of research first and I haven’t touched the subject for about ten years. - But there needs to be a section about comb filters in television systems and other analogue electronics.  Anyway, in analogue TV the comb filter isn’t a small peripheral component of the system, its actually pretty much the heart of the whole decoder. (As I remember) It is the comb filter that breaks the signal up into components and it does a kind of magic that allows a very simple circuit to do a very complex task. In fact I seem to remember that it is use of comb filters that made the whole analogue TV system possible.  I also suspect that the description of comb filters based and focused on delays is only partially correct or complete, it is more of a ‘simplified’ 'scientific' rather than an engineers explanation, has a lot of math, and may actually confuse people. Yes comb filters can or do use delays but the essence of the filter is that it is recursive (a repeated element) - another name for them I have heard is ‘recursive filters‘.  Also I don’t think the shape of the waveform is the place the filter got its name from, its circuit diagram actually looks like a comb or matrix made of resistors, but I think the name came from a more abstract level - the filter orders in a certain way, it was originally concieved as like a comb - it just happens that the waveform looks the same because that is what it does.   The delay based version of the circuit is only one type and there are others. In fact I seem to remember reading somewhere that comb filters are considered a ‘universal’ type (this means that combs can be made to perform almost any function and also that almost any given circuit type can be made to work as a comb). This was probably from an early book on cybernetics, or feedback, computation or AI (my own main subject area).   The final thing not mentioned is the inventor of the comb filter, who I think may be someone like Norbert Werner or one of his friends, but this is purely a guess.   