Nice. Some comments: - he used simulation up front. This is a great thing. Some more detail would have been nice. I tend to design small circuit components up

Nice. Some comments: - he used simulation up front. This is a great thing. Some more detail would have been nice. I tend to design small circuit components up front on paper with a good old fashioned calculator then simulate in LtSpice. It kills a lot of frustration and things you've forgotten about. However it doesn't always work out as SPICE can't deal with parasitic inductance and capacitance easily without adding primitives to the net. This kills you after a few MHz. - The art of electronics is a terrible book IMHO if you want to learn electronics. Even as a reference its not great. It's disjoint and poorly written. Better bet is the ARRL handbook even if you don't do RF stuff. The material is wonderful in that book. Being American though, it is undergoing a transition to SI units though so its a little inconsistent in the maths with random multipliers here and there. - nice to see something without a microcontroller in it and some manual work (coil winding). I still wish all electronics was at this level. Much more fun.