VNA Tools II is free and supports most of the Vector Network Analyzers (VNAs) in today’s market. The software simplifies your tasks of generating accurate measurement uncertainty and vindicating metrological traceability. The software is ideal for flexible and modular external VNA calibration, error correction algorithms, device control, graphical capabilities, and a project-based data analysis. Its speed and performance will optimize the measurement un-certainty computation and propagation through a measurement model in compliance with the ISO-GUM. The software is available for download at www.metas.ch/vnatools. There is a discussion forum where you can find many interesting threads: VNA Tools user forum.