The family of ZNB vector network analyzers (VNA) from Rohde & Schwarz are the perfect instruments for analyzing RF amplifier small signal linear and non-linear performance. This application note presents information on how to configure and use the R&S ZNB vector network analyzer to successfully make accurate and quick measurement of basic RF amplifier parameters. The “SMARTerCal” calibration tool is presented, combining systematic error correction with calibrated receiver power, offering enhanced measurement accuracy with minimum effort.