Abstract: The bandwidth of a two-way broadband signal transmission system is expanded by frequency stacking shared band signals. The up conversion (stacking) and down conversion (destacking) systems utilize matched filters, preferably in a multiplexer configuration, which are directly connected, without a combiner, to output the stacked frequency signal in the case of the up conversion system, and without a splitter to separate the frequency stacked signals in the down conversion system. A single base local oscillator signal is used to generate all of the local oscillator signals needed in the system for up and down conversion.

Abstract: The basic element of a modular, bidirectional broadband programmable switch system is a switch module having a thin rectangular housing with a single first connector preferably in the center of an elongated rear face and n second connectors equally spaced along the elongated front face. Broadband switches within the module selectively connect the single first connector with any one of the second connectors to provide an n.times.1 or 1.times.n switch. Up to n of the switch modules can be stacked side-by-side with an additional module extending transversely with its n second connectors connected to the first connectors on the stacked modules to provide an n.sup.2 .times.1 or 1.times.n.sup.2 switch. The first connectors on the additional modules of two such stacks can be connected to provide an n.sup.2.times.n.sup.2 switch.

Abstract: A conventional STOP/SLOW traffic control sign mounted on a pole is supported and remotely operated by a portable stand having a tubular support mounted on a foldable frame which also carries a remotely controlled drive assembly so that the sign can be operated at a safe distance even by a person with disabilities.