thanks. So basically the beam scan mechanism has a fixed speed inside TVs, but it "waits" for the signal during synchronisation periods, which allows to effectively draw a little faster or a little slower if those sync signals come early/late? The pixel clock, however, is universal for a NTSC or PAL signal, right?[Edit] Or I am totally à la rue and there is no notion of pixel at all in an analog TV set? Meaning that you expect the beam to advance at a certain speed — which is roughly the same across TV sets, but not always, hence the under/overscan to take in account, and the colour is constantly "outputted" as it is decoded by the signal. Meaning that there is not a proper "number of pixels", except that the decoding, because it's FM, can only be sampled at a maximum frequency, limiting the number of effective pixels (hence the 512 or 720 pixel limit that machines would suggest?).