The Echo is a hand-held Vector Impedance Analyzer (Vector Network Analyzer), Spectrum Analyzer, Power Meter, and Frequency Domain Reflectometer (FDR) in one instrument. Echo models come in frequency ranges of 4MHz-to-1.0GHz or 4MHz-to-2.5GHz. The VIA Echo Network Analyzer was designed for performing antenna testing and tuning, transmission line testing and fault locating, cellular site turn-up testing and troubleshooting. It can be used for individual component testing, system or network testing. In a production environment Echo can be used to verify components and assemblies the same as equivalent Agilent (old HP) Network Analyzers at a fraction of the cost.