Circuit parameters -- Conventional ring hybrids -- Asymmetric ring hybrids -- Asymmetric branch-line hybrids -- Conventional three-port power dividers -- Three-port 3-dB power dividers terminated in different impedances -- General design equations for N-way arbitrary power dividers -- Asymmetric ring-hybrid phase shifters and attenuators -- Ring filters and their use in a new measurement technique for inherent ring-resonance frequency -- Small impedance transformers, CVTs and CCTs, and their applications to small power dividers and ring filters.