When is comes to homebrewing QRP HF radios with simple parts and test equipment, then one of the go-to  guys is Tony Fishpool, G4WIF, current membership chairman of the G-QRP group in the UK, and frequent contributor to its quarterly SPRAT magazine.  Tony is also a co-author with Graham Firth, G3MFJ, of Simple Test Equipment for the QRPer, and numerous articles on equipment building with attention to detail and budget.  Tony believes, along with his co-hearts at G-QRP,  that ham radio does not have to be expensive to be fun. G4WIF is my QSO today.