Info on RF Circuits and Systems

Targeted to explain the theory, design and simulation of RF Circuits and Systems. Focus is on design and simlation of RF building blocks like Low Noise Amplifiers(LNAs), Mixers, Frequency Synthesizers, A/D and D/A converters.
http://www.rf-circuits.info/

Toranj Jewelry - Persian Gemology Website

Toranj Jewelry - Persian Gemology Website - all about gemology and gemstones the first proffesional gemology website online shop for gemstones and jewelry-
http://www.toranj-gem.com/

Lichens and me by Katalin Molnar

This website is about lichens (symbiotic organisms). It contains brief description, publication, photos about them and also refers to other sites with lichenological interests.
http://katalinmolnar.com/