While listening to old previous episodes of the Soldersmoke podcast, I heard many references to the book Solid State Design for the Radio Amateur from the ARRL. Even though the book is now a little dated, most of the theory and advice is as valid now as when it was written back in the late 1970's.
Out of curiosity I did a search on Google and found that it was available for free as a download!
Go to https://archive.org/stream/SolidStateDesignForTheRadioAmateur#page/n0
It's about 79MB in size.
