Thanks, I stand corrected regarding pixel implying a fixed location. A sample it is.

I am not really interested in broadcast TV and how it looks on a CRT TV set. I wanted to be able to understand and compare the graphs for "color under" VTR systems.

I know about Kell factor and about the origins of the Rec. 601.

I like this graph, although I understand that it is TV composite signal, not VTR, and it is in (t, U) coordinates, not in (f, U). Still, I find this kind of pictures useful. I like how it describes what one line is made of.

https://i.ibb.co/2qW1m3d/tv-composite-t-u.jpg