Measurement capability includes return loss, VSWR, cable loss and distance-to-Fault (DTF) analysis. In addition, the S251B features a second port for antenna isolation and gain measurement. A selectable +6 dBm or +30 dBm output and optional Bias Tee enables users to conveniently verify Tower Mounted Amplifier (TMA) gain before and after installation. The S251C’s patented RF interference rejection feature and high dynamic range (>90 dB) enables the S251C to accurately measure antenna-to-antenna isolation in the presence of high RF activity. Data Analysis Software enables assessment of system trends, problems and performance in addition to professional report generation. An optional power monitor is available to make power measurements quickly and easily.