hi every one im a new member in this web site and really i love it and it is very useful my name is zeaad I live in iraq im an the last year in communication engineering and my graduated project is about the QAM (quadreature amplitude modulation ) so pls I need ur help in this can u support me with useful reports about qam and I need a ready electronic circuits uses qam so I can make one and test it pls help me < my love to every one thx.......
I know that for speed encoders they often use offset sets of holes with an optical pickup to determine direction of rotation which is a mechanical version of quadrature. Although I don't think it involves amplitude modulation.