Abstract: An expandable matrix switching system for use in routing video and other signals transmitted over twisted pair cables from a variable number of inputs to a variable number of outputs, the matrix switching system including at least one switch frame having a plurality of input ports for receiving input signals and a plurality of output ports. Each switch frame including a processor for selectively coupling the input ports to one or more of the output ports in response to routing commands from a controller. Each switch frame also including a plurality of cascade output ports coupled to the input ports for cascading input signals to the corresponding input ports of another switch frame in the system. A plurality of the switch frames are connectable one to another providing a scalable matrix switch having a variable number of input ports and output ports controllable as a unitary matrix switch.

Abstract: A method and apparatus for signal transmission in which each of a series of input signals (e.g., RGB baseband video signals) is frequency-modulated onto an intermediate frequency. The intermediate frequency signals thus produced are then fed through RF mixers and frequency-shifted to an assigned transmission channel. Each channel is then RF multiplexed into a composite signal for providing a complete set of input signals to one or more monitors. Each monitor is provided with a splitter to divide the composite multiplexed signal into its RF components, which are fed to RF mixers to be shifted back to intermediate frequency signals. Demodulators convert these intermediate frequency signals to output signals corresponding to the input signals.