Systems and methods presented herein provide for improved duplex communications in an RF cable network comprising a plurality of CMs. In one embodiment, a system includes a CMTS operable to transmit downstream communications to the CMs and to process upstream communications from the CMs. The system also includes a duplex RF communication path between the CMTS and the CMs. The CMTS is further operable to transmit a control signal that directs a first of the CMs to transmit, to direct the remaining CMs to receive the transmission from the first CM, to direct the CMs to report received power levels of the transmission from the first CM, and to calculate RF isolations of the remaining CMs with respect to the first CM based on the reported power levels.