A variable resistance limit voltage circuit system for application to various types of circuit uses light emitting diodes as impedances to limit thermal losses as well as to provide display functions. The transmission circuit includes a phase modulator outputting a phase modulation signal and a power amplifier including a transistor. This item may be designed for use on other outdoor equipment that also needs protection from the elements. In another implementation, the present invention provides a hierarchical network model that facilitates network data management, configuration and display tasks associated with wireless network management systems. The seat includes a plurality of stacking guides and a stacking lip integrally formed therein.