Used with the 8510 system, the 8514A S- Parameter Test Set provides the capability to measure all four S-parameters of a two port device with a single connection over the 500 MHz to 18 GHz frequency range. Measurements to 45 MHz are achievable with some loss (about 30 dB) in dynamic range. The S-parameter test set architecture is ideal for measuring two-port devices where it is not convenient to physically reverse the device to measure the reverse parameters, or for networks that need to be adjusted while being measured with full error- correction employed. The test ports have rugged precision 7-mm connectors and may be adapted to other connector interfaces with the appropriate precision adapters. Along with an integrated, four channel frequency converter, the test set includes two 90 dB step attenuators for changing the incident power level at the test port and two bias networks for applying dc bias to the test port center conductor in active device test applications.