ABSTRACT: The 8201A is a versatile, precision, solid-state instrument with features and performance characteristics suitable for laboratory and industrial applications. It covers a frequency range of 100 kHz to 2.5 GHz. The 8201A modulation analyzer is easy and convenient to use. This document briefly describes the operating information for the Model 8201A Modulation Analyzer and all 8201A-S/### variants, including the descriptions of the front and rear panel controls, displays, connectors, option selections, and instructions for local and remote modes of operation. Typical measurement situations are also described. The 8201A is an updated version of the discontinued Model 8201. The 8201A is fully compatible with the 8201 – the two models have identical operation and specifications.