This manual is divided into sections, such as the Specification and Theory of Operation. Some sections are divided into subsections, such as Product Description and Removal and Installation Procedures. Sections containing procedures also contain introductions to those procedures. Be sure to read these introductions because they provide information needed to do the service correctly and efficiently. Following is a brief description of each manual section. The Specification section contains a description of the DG2040 Data Generator and the characteristics that apply to it. The Operating Information section includes general information and operating instructions. The Theory of Operation section contains circuit descriptions that support service to the module level. The Performance Verification section contains procedures to verify that the DG2040 Data Generator functions properly and meets warranted limits. The Adjustment Procedure section contains a statement explaining that no adjustment is needed for the DG2040 Data Generator The Maintenance section contains information and procedures to perform preventive and corrective maintenance of the DG2040 Data Generator These instructions include cleaning, module removal and installation, and fault isolation to the module. The Options section contains information for servicing factory-installed options. The Replaceable Electrical Parts section contains a statement that refers you to the Replaceable Mechanical Parts. Both the electrical and mechanical replaceable parts are listed in the mechanical section. The Diagrams section contains block diagrams and an interconnect diagram. The Replaceable Mechanical Parts. section includes a table of all replace- able modules, their descriptions, and their Tektronix part numbers.