This manual contains maintenance instructions for the A-7550 Spectrum Ana 1yzer. The i nformati on in this manua1 wi11 enable the techn i ci an to 1. Service, test, repair or replace any major assembly or modul within the test set. 2. Maintain the operating condition of the set to expected performance standards. 3. Understand the principles of operation as they relate to the overall operation of the set as well as to individual circuits. ORGANIZATION This manual is divided into six major sections: SECTION 1 - INTRODUCTION Briefly describes the electrical and mechanical configuration of the A-7550» intended to familiarize the technician with the overall structure of the set. SECTION 2 - THEORY OF OPERATION Describes the A-7550 circuit theory on three levels of complexity, a simplified overview, a functional theory of interactive modules, and a detailed theory of each module. Appropriate block diagrams accompany eachdiscussion. SECTION 3 - PERFORMANCE EVALUATION Contains "covers on" functional checkout procedures for evaluating the performance of the A-7550 in each of its modes of operation and major functions. SECTION 4 - CALIBRATION Contains step-by-step calibration procedures for use at normal calibration intervals or after making repairs or replacements. SECTION 5 - TECHNICAL DATA Contains component layout drawings for all mechanical assemblies, PC Board assemblies, interconnect diagrams, circuit schematics, waveforms and charts reflecting voltage levels keyed to test points.

This manual contains instructions for operating the A-7550 Spectrum Analyzer. It is strongly recommended that the operator be thoroughly familiar with Sections 1 through 3 of this manual before attempting to operate the A-7550. This revision of the A-75 5 0 Operation Manual includes extensive modifications, which include Software Version 2.40 and 3.40. Versions 2.40 and 3.40 add the auto feature to the Plotter Function and enhances Bandwidth Optimization. ORGANIZATION This Operation Manual is divided into the following major sections: SECTION 1 - INTRODUCTION Provides a brief introduction to the A-7550, including standard and optional features. SECTION 2 - INSTALLATION Provides a step-by-step procedure for preparing the A-7550 for operation. SECTION 3 - DESCRIPTION OF CONTROLS, CONNECTORS & INDICATORS Identifies and functionally describes all A-7550 controls, connectors and indicators. SECTION 4 - MENU OPERATION Provides a functional description of A-7550 menu operation and a detailed description of each menu. SECTION 5 - GPIB OPERATION Provides instructions for A-7550/GPIB Interface. SECTION 6 - RS-232 OPERATION Provides instructions for A-7550/RS-232 Interface. SECTION 7 - QUASI-PEAK OPERATION Provides instructions for Quasi-Peak operation. The Appendices of this manual contain A-7550 specifications, and some procedures which are not required for all A-7550 users.