Electronic, Electrical, Electro-mechanical Technicians Study Guide

This study guide is intended to aid applicants, who are experienced in the field of electricity and electronics in their preparation for entry-level examinations. By no means is this study guide intended for, nor should individuals who have not completed some form of formal electrical or electronics training either through a technical training school, college, or military training use it as a sole preparation guide for examination purposes. This study guide presumes the applicant has foreknowledge of the fields of electricity and electronics.

The electrical portion of the examination may include questions from any or all of the following areas of study:

  • Ohm’s Law
    • Demonstrate the ability to perform calculations to determine the unknown electrical quantity when given the two of the fundamental values of electricity.
  • Fundamental Values of Electricity
    • Be well versed with electrical prefixes and have a basic understanding of voltage, current, resistance, and power as well as their units of measurement and abbreviations.
    • Be able to calculate electrical power in watts and combine Ohm’s Law and Watt’s law to find unknown currents, voltages, resistance, and power.
  • Basic Instrumentation and Measurements
    • Demonstrate the ability to use common test instruments as well as interpret scale values on digital meters and interpret linear and nonlinear scales on an analog meter.
    • Demonstrate the ability use an oscilloscope and to interpret a waveform pattern, i.e. determine the voltage and frequency using an oscilloscope display. Understand the terminology associated with test instruments.
  • Basic Electrical Circuits
    • Be able to identify various types of electrical symbols and common circuit devices.
    • Be able to identify various types of resistors and their color code.
    • Understand the relationship of cross-sectional area and length of a conductor as they relate the current in a circuit.
    • Identify the three basic circuit configurations; series, parallel, series-parallel and be able to perform circuit calculations to solve for an unknown electrical quantity, i.e. determine voltage drops, current values, and wattage values.
  • Sources of Electricity
    • Understand the differences between primary and secondary cells.
    • Distinguish between series and parallel connections.
    • Calculate the outputs of batteries in series and parallel.
    • Identify other sources of electrical energy.

  • Motors
    • Understand the operation of various dc motors.
    • Understand the operation of three phase motors.
  • Transformers
    • Understand the operation of a transformer.
    • Identify types of transformer losses.
    • Be able to calculate the various values of currents and voltages in transformer circuits.
  • Alternating Circuits
    • Be able to calculate various levels of ac voltage, i.e. peak to peak, rms, average.
    • Understand the time relationships of an ac waveform, i.e. quarter-wave, half-wave, full-wave.
    • Understand the difference between direct current and alternating current.
    • Be familiar with reactive components, i.e. capacitors and inductors and understand how they respond in both a dc circuit and an ac circuit.
    • Be familiar with formulas associated with calculating the transient response time of both an RC and an RL circuit.
    • Understand resonant frequency and how it affects various RCL circuits. Calculate a resonant frequency.
  • Semiconductors
    • Understand how N-type and P-type materials in a semiconductor conduct electricity.
    • Be able to apply the principles of both forward and reverse biasing.
    • Identify and understand the operation of various types of semiconductor diodes.
    • Understand the operation of a half-wave and full-wave rectifier.
    • Understand power supply filtering.
    • Identify and understand the operation the bipolar transistor.
    • Identify and understand the operation of several common thyristors.

  • Digital Circuits
    • Convert decimal numbers to their binary equivalents and binary numbers to their decimal equivalents.
    • Identify various types of logic gates and their associated truth tables.
    • Be able to apply knowledge of basic logic gates to determine the output of a simple logic circuit.
    • Understand the difference between digital and analog devices and their signals. Identify different types of logic families.

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