Methods and structures to reduce the occurrence of crosstalk and pixel noise in solid state imager arrays. The network hub also includes a removable and replaceable termination element that mates with the second connector to provide signal connectivity between selected ones of said plurality of cables. Positioned proximate to the discharge end of the conduit is an electrically conductive reference device. Tolerance and softness volumes are defined in this way, and a transformation is defined for each. The switching center can also be used as an adjunct to a private branch exchange to provide in-building wireless services and call control.