|Basic Electronics: Theory and Practice|
Authors: Sean Westcott, Jean Riescher Westcott
The is the third edition of a book I reviewed some time ago. All of the typos and errors that I noticed then have gone, but there are some new ones - Figure 15.8 for example isn't what it says it is.
Overall the book is well written and well put together - the big problem is that it is a random walk though various topics in electronics and all presented in an entirely standard way. You might say what is wrong with the "standard way"? The answer is that if you are trying to learn "applied" electronics then you probably don't need to start with a study of atoms and their structure.I'm not saying that this is an unimportant topic only that it has little to do with understand how electronic circuits work at a functional level. The coverage is uncessarily complete and theoretical - for example if you have just been introduced to the idea that electricity is a flow of electrons do you really need to be introduced to the idea of a flow of holes?
Part 1: The Fundamentals comprises three chapters which look at simple ideas of electricity - Ohm's Law and power, AC and DC, waveforms, fuses and so on - a whole collection of everything. In this first part we meet everything you would meet in a first course on electricity only with very very little depth. There is certainly no math and very little physical insight. For example, the section on putting things in series and parallel makes no attempt to point out that series means same current though each component and parallel means same voltage across each component - let alone introduce the basic formulae for resistors in series/parallel. In short after Part 1 you would have some vague ideas about electricity and a fair bit of puzzlement about concepts that you really didn't need. I'm sure that you wouldn't be able to reason about a simple new circuit you were presented with.
Part 2: Your Workspace and Tools is all about practical skills - how to use a multimeter to measure DC, AC, Resistance and current and some general information on tools. There is a section on how to create a workshop that is safe to use - lighting, ventilation and so on. This is best described as inspirational.
Part 3: Electronic Components starts with a, perhaps an overly detailed, chapter on switches of all types. Then comes a chapter on resistors - an important component, but this is all mixed up with theory rather than just practice. Here we at last meet the formulas for resistors in series and parallel, but also the more advanced Kirchhoff's Law and, while I know Kirchohoff's Law, I can't remember when I last used it in designing or understanding a circuit. The next obvious component to deal with is the capacitor, and again the problem is we have rather too much detail - including relative permittivity. At the end of this chapter you will have a vague idea of what a capacitor is all about, but there are lots of missing important detail. We also encounter some very strange ways of expressing things:
"Once a capacitor is charged the voltage that flows through the capacitor is the same as the voltage that enters it."
I can't imagine any electronics person thinking of voltage as something that flows. Even if you allow for looseness in language, I still have no idea what this means. It is deeply misleading. There are other places where things read as if there was little understanding. At the end of this introduction you will have an idea that capacitors charge and discharge, but you will have no idea of what happens when you apply AC and no idea of anything like filtering or tuning. Of course, you really can't get a full picture because the final passive component - the inductor or coil - is more or less ignored. This part ends with a look at diodes, transistors and power supplies and at the end you are not going to understand much of how they work - especially in the case of diodes and transistors.
Part 4: Getting to Work returns to the practical with a long look at soldering. Again too much detail - who needs to know about eutectics in this day and age. How to solder with lead-free solder - now that would be a skill worth talking about, but of course it isn't. The next project is to build a mains power supply using a kit - not the best project for a beginner given the lethal voltages it involves.
Part 5: Going Digital is about digital electronics and it mostly does no harm. It also goes into details about analog ICs such ampilifers, memory and microcontrollers.
Part 6: Electronics in Practice is another practical session with a look at motors, including the H bridge, sensors and communications where you build an FM transmitter.
Part 7: Building a Robot and Using Raspberry Pi is devoted to building a robot using either an Arduino or a Netduino - the instructions are given twice once for each device, or a Raspberry Pi. All fine and interesting, but this doesn't really help you understand basic electronics and takes many pages that could have been devoted to the main topic. Why go off into robots and programming when designing a simple one-transistor buffer or current-limiting resistor for an LED is still beyond the reader's skill set?
There is also a CD bound into the back that includes videos of the labs and demonstrations.
This is a book I cannot recommend. It is a collection of things you do need to know about but the selection is arbitrary. It is what you would get if you sat down with an academic book on electricity and electronics and picked bits out that you thought were relevant and removed all the math. It doesn't help you think about electricity and electronics and many of the explanations are very odd indeed - see voltage that "flows" quoted earlier. Finally, despite lots of warnings about the dangers of mains voltage, is it really necessary to have a major project that exposes the beginner to such lethal voltages? There are plenty of safer projects.
|Last Updated ( Tuesday, 04 August 2020 )|