Although I already got some answers to my questions, I copy my mail here, that I sent You a few days ago:
After watching several tutorila video from You, I have now a question about designing the differential pairs.
In this video www.youtube.com/watch?v=Lb3sEcolkOA
You edit the differential pairs rule properties upon a
pdf document of a PCB stackup. My question is that is it a general 12-layer stackup of a manufacturer, where
I can find track properties for a new design, or is it a calculated, based on an exact design?
If I'd like to start a new design I need a stackup from a selected manufacturer, where I can see the thickness of
layers, materials. Right? Or I can send my final design and then they can calculate the impedances from my
gerbers and can recommend the track widths and gaps? How it works, which step is the first?