This chapter provides an overview of the MS2085A/89A Site Master VNA user interface and describes the main graphical displays and menus presented in the VNA mode. This chapter also includes VNA fundamentals.

The Site Master VNA mode can measure the magnitude and phase characteristics of 1-port or 2-port networks, including cables, antennas, filters, isolators, and attenuators.

VNA provides advantages over Cable-Antenna Analyzer Mode via more advanced measurements, more flexibility, and more calibration choices. The main advantages are scattering parameter (S-parameter) choices, graph type choices, and domain choices. In VNA mode, these three measurement choices can be mixed and matched to provide users with more freedom and flexibility. For simplicity in Cable-Antenna Analyzer mode, the choices are more fixed and limited. Advanced graph types allow you to look at the same device measurements in many different ways. The ability to display four traces provides you with the flexibility of comparing various measurements to obtain the results you need more efficiently. Advanced graph types such as Group Delay, Real, Imaginary, inverted Smith Chart, Real Impedance, and Imaginary Impedance are available in the MS2085A/89A in addition to the standard graph types, Log Mag, SWR, Phase, and Smith Chart. The MS2085A/89A gives you the ability to display four traces overlaid, or they can be displayed in individual graphs. In Cable-Antenna Analyzer Mode, the MS2085A/89A is a two-port, 1-path instrument. In VNA Mode, the MS2085A/89A is a full-reversing VNA that is capable of measuring all S-parameters (S11, S21, User, and S21 (Ext. Sen)) of a 2-port device with a single connection. Being able to measure both forward and reverse S-parameters allows you to use more advanced calibration methods and to make more accurate measurements of a 2-port device.