Basic Electronics: Theory and Practice |
Authors: Sean & Jean Riescher Westcott If you want to get into the Internet of Things then it helps to have some idea of what electronics is all about. This book aims to take you from basic physics to programming an Arduino - is this possible?
When I think about the years that I spent learning electronics, not to mention all the physics and maths needed to make sense of it, I have difficulty believing that a short book such as this one can cover so much ground. The book is divided into seven short parts and it really does attempt to take you from basic physics to robots. The first part is on the Fundamentals and the opening chapter explains atoms, electrons, the periodic table, conductors, insulators and semiconductors. It also tries to explain the idea of electron v hole currents, a difficult concept that could have been avoided by not dealing with junction transistors, instead confining the discussion to FETs, later on in the book. This is just one of many occasions in which the desire to cover everything means that the beginner is challenged by difficult ideas that aren't essential to getting started. The rest of the section works through basic ideas of electricity - EMF, Voltage, Ohms Law, power, direct v alternating current, wave forms, phase, circuit diagrams and serial and parallel. The approach is dry and, while there is no deep math, there are simple equations. Unfortunately there are number of small but important typos in the book. For example, on page 20 we have P=V*R which should be P=V*I. Overall, the presentation in this section is just too fast. Some topics get a single paragraph that explains nothing at all. Better to leave them out and spend more time on explaining the core ideas.
Part 2 consists of two chapters on workshop craft. There are a few notes on keeping things clean and tidy, lighting, ventalation and safety. You also get to discover how to use a multimeter, but no real discussion of what sorts of other instruments you might find useful and nothing about how to prototype a circuit. It is a fun section, but inadequate for the modern electronics world. Part 3 goes over the different electronic components you will encounter - switches, resistors, capacitors, diodes, transistors and power supplies, What happened to inductors? Well they get a bit of a look-in in the chapter on power supplies as transformers. Apart from the chapter on switches, and perhaps the one on resistors, the chapters are all too short and too shallow. You can get some way with explaining capacitors as charge storage devices, but explaining what they do in AC circuits is well beyond the scope of this book - it doesn't even attempt it. This is reasonable, but why then complicate matters with a mention of relative permittivity? The explanation of diode action is adequate, but as soon as we hit transistors the potential for getting lost goes up. The chapter starts with a look as Bipolar Junction Transistors, arguably the most complicated three-terminal device known to electronics. Later the chapter does introduce the FET, which is a much easier-to-understand active device, but even here you have to wonder why it is necesary to introduce all the different possible types?
Part 4 is called "Getting to Work". It starts off with a look at soldering in more depth including desoldering. Then you get to make a power supply but you have to buy a kit to do it. I'm also not at all sure that the place to start with practical electronics is to build a mains power unit even with the warnings provided about the danger. A battery operated cicruit might be better. Part 5 is on digital and starts off looking at truth tables, but varies the format without explanation and gets the table for NAND wrong. It then goes onto basic logic circuits - AND and OR - and a brief intro to binary numbers. Then onto the 555 timer, encoders, decoders and a guitar amplifier using a kit and an op-amp. The next chapter deals with computer organization before the book moves on to micro-controllers - the Arduino and Netduino specifically - why two when this is just supposed to be teaching you what a micro-controller is and how to use it? Part 6 is another practical section covering motors, servos, steppers, a bridge motor controller and pulse width modulation. Then there is an almost abstract chapter on sensors, including some that are just too sophisticated for the reader to understand. Rather than starting with a single sensor, like a thermistor or an LDR, it starts with an accelerometer then goes on to digital compasses. This is such a shallow view of the topic it is hardly worth having. The final chapter introduces communications and the electromagnetic spectrum. Again the topics are dealt with so quickly that apart from letting you know they exist not much is accomplished. Part 7 show you how to construct a robot using an Arduino or a Netduino. The only difference between the two controllers is the language used to program them, but because two controllers are used the chapters have to be duplicated, even though the information is very nearly the same.
What this book does is to give the reader some idea of how huge a subject eletronics is. It makes no attempt to find or provide a simplified path into the subject that a non-technical reader might find easier. It simply presents a huge overview of the subject with nothing treated in sufficient depth that it is likely to be useful to the reader in a practical situation. It would be a better book if it limited itself to a small range of ideas directly useful in modern electronics. Not recommened because it covers too much in too little depth.
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Last Updated ( Friday, 26 June 2015 ) |