Electronics Calculations Data Handbook

Daniel McBrearty

• Publisher: Newnes
• Year: 1998
• Print ISBN: 9780750637442
• eBook ISBN: 9780080530772
• Topic: Technology & Engineering
• Subtopic: Industrial Design
• Index: Technology & Engineering

Electronics Calculations Data Handbook is a unique handbook consisting of tables compiled as a labour-saving aid for electronics engineers, designers and technicians. The layout and content of these is designed to make them easy to use, and to contain the most valuable but tough to calculate information. Daniel McBrearty compiled this book as a result of bitter experience as an analog designer, initially prototyping and testing the ideas of other folk, and seeking to make those little changes that can make the difference between a good and really excellent circuit, and later doing the whole thing himself. If you don't know off the top of your head the best pair of E24 resistors to make an inverting op-amp stage of 18dB gain (and who does?) then this book will save you hours and protect your sanity in a world in which your calculator always goes missing, and you've forgotten the formula. - All the key data needed by electronics designers, engineers and technicians - Saves on hours of needless number-crunching - Must-have information at a glance

Part One

Basic Concepts

Introduction to Part One

In this part of the book we take a look at the founding principles of electronics, from voltage, current and Ohms Law to some basic ways to analyse circuits mathematically. If you know all of this then skip it, using it for reference as required. If not then read on.

I have tried to arrange ideas so that you are introduced to them sequentially, but this is a bit impractical in places. So if you are a real newcomer to electronics I’d like to suggest two readings; the first to get an overview of each topic, the second to cross-refer between them and to begin to see how they relate to each other.

1

Fundamentals

To the beginner

Before getting into the technical stuff, we might wish to ask ourselves what electricity is. My first recollection of thinking about it (though I did not know that I was) is of being a child and dismantling a prized radio to find out that no one was inside; just a mind-boggling collection of small coloured objects which evidently were not sweets, though some looked like them. My first direct experience of electricity was more sudden; an electric shock from a bar fire while trying to melt some plastic on it. I knew it was hot, but hadn’t expected that! Later I came across the manual for a record player and amplifier in the house, which was old-fashioned enough to come with a circuit diagram. I was fascinated by it. It meant something to someone, but these hieroglyphics were like no language that I could figure out.

Later I took a technician’s course, and a confusing set of concepts was presented to me as explanation for this unseen and magical force. Electricity, I had now realised, is used in a huge range of ways; recording sound, reproducing pictures, lighting our darkness and a lot else besides. All this was, they told me, due to unseen little balls which whiz around in some materials, creating equally unseen lines which can cause little balls in other places to whiz around as well. And this the mental territory of staid, rational looking people who would probably claim that they don’t believe in magic.

I have to confess that, some years later, I have still not seen the little balls or the lines which they fling about, and I’m not very sure that I really understand them. But I have managed a reasonable career as a technician and an engineer, and I believe that I would have a fair chance of fixing my cassette machine, TV or house wiring should they misfunction. On the whole, I have not thought about the antics of little balls very much (though I suppose that it helps to know that they are there). Electricity looks, in my mind, more like water, wires like pipes, resistors like very thin pipes, capacitors like pairs of half-filled balloons which squash against each other, and inductors like – well something else. (I never said that the analogy was complete or accurate.)

I say all this as, I hope, a source of comfort to the new student of the subject who may be suffering the same pangs of insecurity about atoms, electrons and so on that I went through. Unless you feel strongly to do otherwise, let them live their own strange lives. You can be a very competent and effective user of the principles of electricity and electronics without needing to know much about them (though the same might not be said of completing your college course). Leave it to the physicists. What helps a great deal is having a good and clear grasp of the laws of electricity, and being able, as much as is possible, to prove them to yourself.

What is electricity?

We are never concerned with the behaviour of an individual atom in electronics; but with their movement in vast numbers, as they fling themselves, lemminglike, around the wires of your circuit. And yet we hardly think of them at all. We think a great deal about ‘voltage’, ‘current’ and about the golden rule of electronics, Ohm’s Law. You will meet these soon.

Actually it is not atoms that move, but mostly bits of them, even tinier particles called electrons which separate themselves somehow from the larger atom which is their usual home. These electrons are now called ‘free electrons’. Though unimaginably small, they are pretty powerful. They carry something which is called a ‘negative charge’ which is another way of saying that if, having been separated from the parent atom, they should ever encounter another with a vacancy then they will be in there like a shot and pretty difficult to move. And the feeling is mutual; once it has lost an electron the atom feels the loss and will try to bring close to it any waifs that it senses nearby. Being much bigger, it moves much less easily, or not at...

Table of contents

• Cover image
• Title page
• Table of Contents
• About the author
• Copyright
• Preface
• Acknowledgements
• Part One: Basic Concepts
• Part Two: Resistive Circuits
• Part Three: Reactive Circuits
• Part Four: Operational Amplifier Circuits
• Appendix 1: Units, symbols and suffixes
• Appendix 2: Colour codes
• Appendix 3: The decibel
• Appendix 4: Complex number analysis
• Further reading
• Index