some links to useful webpages relating to RF technology :
RF weblinks
Japanese "i-Laboratory" Microstrip calculator
University of San Diego : Course EEE194
University of Kansas : Course EECS723
Stephen D. Gedney (University of Kentucky
Steve Long - University of California - Santa Barbara
Parameter conversion (S, z, y, ABCD, T)
Gunthard Kraus S-Parameter Library
Online S-Y-Z parameter converter
Online L-Matching Network Calculator
Alexander C. Frank online L-Matching Network Calculator
Ernie Kim online L-Matching Network Calculator
Online RF Amplifier Design Calculator
Wikipedia page on Electronic Oscillators