CHAPTER 2 COMPONENT TESTING

2-1 CHAPTER 2 COMPONENT TESTING LEARNING OBJECTIVES Upon completion of this chapter, you will be able to do the following: 1. Explain the importance of testing individual electronic components. 2. Identify the various methods of testing electron tubes. 3. Identify the various methods of testing semiconductors. 4. Identify the various methods of testing integrated circuits. 5. Identify the various types of testing batteries and their characteristics. 6. Identify the various methods of testing rf attenuators and resistive loads. 7. Identify the various methods of testing fiber-optic devices. INTRODUCTION TO COMPONENT TESTING It is imperative that you be able to troubleshoot an equipment failure to the component level. In the majority of cases, Navy technicians are expected to troubleshoot and identify faulty components. This chapter, "Component Testing," will acquaint you with alternative methods of testing various components and their parameters. A quick glance at the Navy’s mission and concept of operation explains why we, in most cases, must be able to troubleshoot to the faulty component level. A ship must be a self-sustaining unit when deployed. Storage space is a primary consideration on most ships and a limiting factor for storage of bulky items or electronic modules as ready spares. Therefore, it is practical to store only individual components common to a great number of equipment types. This of course, limits the larger replacement modules available to you during troubleshooting. Q-1. Why are most ships limited in their ability to stock replacement modules for repair of electronic equipment? TESTING ELECTRON TUBES In equipment that uses vacuum tubes, faulty tubes are responsible for more than 50% of all electronic equipment failures. As a result, testing of electronic tubes is important to you. You can determine the condition of a tube by substituting an identical tube known to be good for the questionable one. However, indiscriminate substitution of tubes is to be avoided for at least the following two reasons: (1) detuning of circuits may result and (2) a tube may not operate properly in a high-frequency circuit even though it performs well in a low-frequency circuit. Therefore, your knowledge of tube-testing devices and their limitations, as well as correct interpretation of the test results obtained, is indispensable for accurate and rapid maintenance.