The Mysterious 50 Ohm Impedance: Where It Came from and Why We Use It (2021)
Just a quick comment on the product, since this it effectively an ad for Altium.They typically present themselves as the most popular solution, but they also very clearly out-price any hobbyist at $10k for a perpetual licence. Their "hobby" version CircuitStudio lacks critical features and has 0 support and 0 updates and the forums are just crickets. But KiCad is free, open source, and looks similar enough that I had a great time following the Altium tutorials by Rick Hartley with it.In my opinion, that also invalidates their claim that Altium is the most commonly used PCB design software, because there likely are 100x more hobbyists using KiCad than people able to spend $10k on a hobby.It seems to me like Altium is developing like Eagle. They used to court the makers and hobbyists and then greatly profited when those people started working. But now both of them are mostly in the business of milking companies who have existing data in their proprietary file format.