RE: Workings of the pickup coil?
I commend your curiosity.
If it works, I'm happy. I'm not the kind of guy who needs to know exactly why everything works the way it does. I'm focused on the internal workings of the 2-stroke, rather than the ignition system.
It would be cool to see someone actually post diagrams and the physics behind why a magneto ignition works. But, I doubt I'd understand it.
When it comes to electronic stuff in this hobby--there's only one thing that matters to me. Does it work? If it does--then don't screw with it. If it doesn't, then go buy a different/new one. I hate screwing with stuff that doesn't work.
Good luck. I hope someone can answer your question.