Electronic instruments: theory, applications, and real-world practice.
Electronic Test Instruments: Analog and Digital Measurements, Second Edition offers a thorough, unified, up-to-date survey of the entire field of electronic instrumentation: instruments and techniques, digital and analog.
Robert A. Witte first introduces basic measurement theory, then covers each type of commonly used electronic test equipment. Using detailed examples, Witte shows how these systems are applied in real-world applications, introducing core functionality and showing how to choose the right instrument for each task. This new second edition has been updated throughout, reflecting the latest technologies and presenting extensive new coverage of digital oscilloscopes and power supplies.
1. Measurement Theory.
Electrical Quantities. Resistance. Polarity. Direct Current. Power. Alternating Current. RMS Value. Average Value. Crest Factor. Phase. AC Power. Nonsinusoidal Waveforms. Harmonics. Square Wave. Pulse Train. Combined DC and AC. Modulated Signals. Decibels. Absolute Decibel Values. Measurement Error. The Loading Effect. The Voltage Divider. Maximum Voltage Transfer. Maximum Power Transfer. Impedance. Instrument Inputs. Bandwidth. Rise Time. Bandwidth Limitation on Square Wave Digital Signals. Logic Families. References.
DC Voltmeters. AC Voltmeters. RF Probes. Ammeters. Ammeter Used as a Voltmeter. Voltmeter Used as an Ammeter. Current-Sense Resistor. AC Ammeter. Ohmmeters. Voltmeter-Ammeter Method. Series Ohmmeter. Current-Source Method. 4-Wire Ohms Measurements. Multimeters. Meter Range. Other Multimeter Functions. Specifications. References.
Circuit Model. Floating and Grounded Outputs. Sine Wave Sources. Imperfections in Sine Wave Sources. Function Generators. Pulse Generators. RF Signal Generators. Summary of Signal Sources. References.
Analog Scope Block Diagram. Digital Scope Block Diagram. Sample Rate. Real-Time Sampling. Repetitive Sampling. Triggering. Acquisition/Sweep Control. Vertical Amplifier. Vertical Resolution. AC and DC Coupling. Bandwidth Limit. X-Y Display Mode. High Impedance Inputs. 50-W Inputs. Digital Acquisition and Display Techniques. Oscilloscope Specifications. Scopesmanship. Mixed Signal Oscilloscope. Oscilloscope Probes. Probe Compensation. Active Probes. Differential Measurements. High-Voltage Probe. Current Probes. References.
Voltage Gain Measurement. Phase Measurement. Frequency Measurement (Lissajous Method). Digital Signal Measurement. Frequency Response Measurement. Square Wave Test. Linearity Measurement. Curve Tracer Measurement Technique. Diode I-V Characteristic. Resistor I-V Characteristic. Amplitude Modulation Measurement. Power Measurement. FFT Measurements. Basic Time Domain Reflectometry. References.
Basic Frequency Counter. Frequency Dividers. Period Measurement. Reciprocal Counter. Universal Counter. Gated Counter Measurements. Timebase Accuracy. Input Impedance. Frequency Counter Specifications. Time Interval Analyzer. References.
Power Supplies. Circuit Model. Constant-Voltage Operation. Constant-Current Operation. CV-CC Operation. Overvoltage/Overcurrent Protection. Remote Sensing. Measurement Capability. Power Supply Specifications. References.
Spectrum Analyzers. Bank-of-Filters Spectrum Analyzer. FFT Spectrum Analyzers. Wavemeters. Resolution Bandwidth. Narrowband and Broadband Measurements. Swept Spectrum Analyzers. Spectrum Analyzer Measurements. Network Analyzers. Distortion Analyzers. RF Power Measurements. RF Power Meter. References.
Logic Probes. Oscilloscope Logic Measurements. Logic Analyzers. Timing Analyzer. Glitch Detect. Digital Logic Test Example. State Analyzer. Data Formats. State Display. Timing Display. Microprocessor Measurement. Storage Qualification. Trigger Events and Sequencing. Microprocessor Program Flow. Logic Analyzer Probing. Combined Scope and Logic Analyzer. PC-Hosted Logic Analyzer. References.
Resistance Measurement-Indirect Method. Output Resistance. Input Resistance. Bridge Measurements. RL and RC Circuits. Resonant Circuits. Diode Measurement Circuit. Instrument Connections. Attenuators. Power Splitters and Combiners Measurement Filters. References.
Average (Mean) Value of a Waveform. RMS Value of Waveform. Full-Wave Rectified Average Value of a Waveform. Bandwidth and Rise Time for a Single-Pole System. Frequency Response Due to Coupling Capacitor. Polar and Rectangular Formats. Resonant Frequency.
This book is for the electrical engineer, technician, or student who understands basic electronics and wants to learn more about electronic measurements and test instruments. To use electronic instruments effectively, it is necessary to understand basic measurement theory and how it relates to practical measurements. Basic measurement theory includes such things as how a voltage waveform relates to its frequency and how an instrument can affect the voltage that it is measuring. In an ideal world, we would not have to know anything about the internal operation of an instrument to use it effectively. Although this ideal situation can be approached, it cannot be obtained completely. (One does not have to know how a gasoline engine works to drive an automobile. However, a driver does need to understand the function of the accelerator and brake pedals.)
To minimize dealing with the internal workings of an instrument, circuit models and conceptual block diagrams are used extensively. Circuit models take a "black box" approach to describing a circuit. In other words, the behavior of a complex circuit or instrument can be described adequately by conceptually replacing it with a much simpler circuit. This circuit model approach reduces the amount of detail that must be remembered and understood. Conceptual block diagrams show just enough of the inner workings of an instrument so that the reader can understand what the instrument is doing, without worrying about the details of how this is accomplished.
In all instrument categories, the traditional analog technologies have been overtaken by digital technology. More precisely, the old analog approach has been replaced by precision analog circuitry that is enhanced by the power of analog-to-digital converters, digital logic, digital signal processing, and measurement algorithms implemented via software. However, a voltage measurement is still a voltage measurement, whether an analog meter or a digital meter is used. Since the measurement is fundamentally the same, this book treats both technologies in a unified manner, emphasizing digital instruments and highlighting the differences between the analog and digital approaches when appropriate.
This book does not attempt to be (nor can it be) a substitute for a well-written instrument operating manual. The reader is not well served by a book that says "push this button, turn this knob" because the definition of the buttons and knobs will undoubtedly change with time. Instead, this book is a reference, which provides the reader with a background in electronic instruments. Variations and improvements in instrument design cause each meter, oscilloscope, or function generator to be somewhat unique. However, they all have in common the fundamental measurement principles covered in this book.
This second edition of the book includes updates to all of the chapters, incorporating recent developments in technology while still remaining focused on the concepts and principles that last over time. The oscilloscope chapters were expanded, with an increased emphasis on digital oscilloscopes. The section on power supplies was expanded into its own chapter.
Chapter 1 covers the basic measurement theory and fundamentals. Chapters 2 through 7 cover the mainstream instruments and applications that the typical user will encounter (meters, signal sources, oscilloscopes, frequency counters, and power supplies). Chapter 8 introduces spectrum analyzer, network analyzers, and RF power meters while Chapter 9 covers logic probes and logic analyzers. Chapter 10 rounds out the book with some important circuit concepts and techniques that enable quality measurements.
My original motivation to write this book was my experience in teaching electrical engineering circuit theory courses. Even students with a good background in electrical theory seem to have trouble relating the textbook concepts to what is observed in the laboratory. The concepts of the loading effect, grounding, and bandwidth are particularly troublesome, so they are emphasized throughout the book.