A Geek Girl's Guide to Electronics and the Internet of Things E-Book

Audrey O'Shea

• Herausgeber: John Wiley & Sons
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 603

Veröffentlichungsjahr: 2020

Beschreibung

A straightforward demystification of electronics and the Internet of Things A Geek Girl's Guide to Electronics and the Internet of Things breaks down and simplifies electronics and the Internet of Things for the layperson. Written by a leading technical school instructor with a talent for bringing complex topics to everyday people, this book provides concrete examples and practical advice for anyone interested in building, repairing, or studying electronics and functional Internet of Things (IoT) devices. A Geek Girl's Guide to Electronics and the Internet of Things explores a wide range of topics including, among others: * Ohm's and Watt's Law * Series and Parallel Circuits * Diodes, transistors, capacitors and relays * Motors and Pulse with Modulation * Using light to control electricity * Photovoltaic Cells and Transducers * Enhancing circuits with Arduino * Connecting circuits to networks The distinguished author's website includes videos to help you build and enhance projects, along with deeper information to enrich your learning. Additionally, the book goes beyond theory and teaches readers how circuit components become IoT devices and provide the data that drive our modern world. The combination of hands-on activities and solid pedagogy ensures long-lasting retention of the material for everyone.

Leseprobe

Table of Contents

Cover

Introduction

Who Will Benefit Most from This Book

Sourcing Parts and Supplemental Materials

Special Features

What Does This Book Cover?

Part I: IoT and Electricity Basics

CHAPTER 1: IoT and Electronics

IoT in a Nutshell

Parts of an IoT System

Challenges in Implementing IoT

IoT into the Future

CHAPTER 2: Electricity: Its Good and Bad Behavior

Try This: Creating Some Static

Electricity at an Atomic Level

Conductors and Insulators

Characteristics of Electricity

Induction and Conduction

Try This: Creating a Simple Breadboard Circuit

The Basic Circuit

Circuit Protection Devices

CHAPTER 3: Symbols and Diagrams

Types of Diagrams

Schematic Symbols

So Many Switches!

Drawing Your Circuit

Try This: Adding a Switch and Creating a Schematic

CHAPTER 4: Introduction to the Arduino Uno

What Is Arduino?

The Arduino Board

Analog vs. Digital

The Arduino IDE

Try This: Creating a Simple Arduino-Controlled Circuit

Try This: Changing Pins

Try This: Creating Arduino Running Lights

Try This: Adding a Switch to Your Circuit

Try This: Using the Serial Monitor

CHAPTER 5: Dim the Lights

Using a Multimeter

Try This: Repurposing a Power Supply

Measuring Voltage, Current, and Resistance

Try This: Dimming the Lights

Try This: Measuring Circuit Values

Using Arduino to Measure Electricity

Try This: Using an Arduino Voltmeter

Try This: Using an Arduino Ohmmeter

Try This: Using an Arduino Ammeter

Try This: Using an Arduino Continuity Tester

Try This: Building a Dimmable Arduino Camp Light

Soldering, Perfboards, and Shrink Tubing

CHAPTER 6: Feel the Power

Watt’s Law and the Power Wheel

Watts and Horsepower

Battery Power

The Other Resistor Value

Wattmeters

Try This: Using an Arduino Wattmeter

CHAPTER 7: Series and Parallel Circuits

Series, Parallel, and Complex Circuits

Try This: Testing Series and Parallel Configurations

Calculating Values in Series and in Parallel

Sources in Series and Parallel

Try This: Calculating Circuit Values

Part II: Using Common Components

CHAPTER 8: Diodes: The One-Way Street Sign

Try This: Creating a Simple Polarity Tester

Determining Anode and Cathode

Types of Diodes

Try This: Using a Seven-Segment LED

CHAPTER 9: Transistors

Try This: Using a Transistor as an Amplifier

The Purpose of Transistors

Types of Transistors

Try This: Using a Transistor as a Switch

CHAPTER 10: Capacitors

A Quick Look at Capacitors

Try This: Creating a Time Delay Circuit

Capacitor Uses

Try This: Creating an Astable Multivibrator

Try This: Using Capacitors in Series and Parallel

CHAPTER 11: The Magic of Magnetism

The Electricity/Magnetism Relationship

Try This: Building an Electromagnet

Magnetism in Circuits

Relays

Try This: Building a Relay Oscillator

Try This: Setting Up an Emergency Lighting System

CHAPTER 12: Electricity's Changing Forms

Try This: Creating a Water Alarm

Common Transducers

Try This: Creating a Night-Light Circuit

Try This: Creating an Arduino Laser Security System

CHAPTER 13: Integrated Circuits and Digital Logic

Integrated Circuits

Try This: Creating an Astable Multivibrator

Operational Amplifiers

Digital Logic

Try This: Exploring AND and OR Gates

Logic Probes and Oscilloscopes

Part III: More Please

CHAPTER 14: Pulse Width Modulation

Pulse Width Modulation Explained

Try This: Using a PWM LED Dimmer

Try This: Using a PWM Motor Control

Try This: Trying PWM and an Arduino

CHAPTER 15: Sources of Electricity

Chemical Reactions

Try This: Making a Thermocouple

Light

Try This: Displaying PV Output on an Arduino

Friction

Magnetism

Pressure

Wrapping It Up

CHAPTER 16: Transformers and Power Distribution

What Is a Transformer?

Try This: Verifying Transformer Output

Alternating Current Values

Power Distribution Using Transformers

CHAPTER 17: Inverters and Rectifiers

Inverters vs. Rectifiers and Their Uses

Construction of Inverters

Try This: Filtering a Circuit

Construction of Rectifiers

Single-Phase vs. Three-Phase Power

Try This: Building a Small Variable Power Supply

CHAPTER 18: Radio Waves and Tuned Circuits

Radio Waves

Try This: Building a Radio Receiver

Making Waves

Try This: Building an Arduino FM Radio

Tuned Circuits

Part IV: Putting the I in IoT

CHAPTER 19: Connecting Your Circuits to the Cloud

The Arduino IoT Cloud

Try This: Setting Up Your Device

Try This: Using Things, Properties, and Widgets

CHAPTER 20: Just for Fun

Electronic Fabrics and Wearables

Try This: Lighting Up a Teddy Bear

Paper Circuits

Try This: Creating a Conductive Paint Circuit

Try This: Creating a Copper Tape Circuit

Try This: Building Squishy Circuits

CHAPTER 21: What's Next?

The World Is Your Oyster

Recommended Reading and Resources

Words of Encouragement

Index

End User License Agreement

List of Tables

Chapter 3

Table 3.1: Commonly Used Electronics Designators

Chapter 7

Table 7.1: Series and Parallel Circuit Rules

Chapter 8

Table 8.1: Sample LED Voltage Ranges

Chapter 15

Table 15.1: Primary and Secondary Cells

List of Illustrations

Chapter 1

Figure 1.1: An IoT system

Chapter 2

Figure 2.1: Bending water

Figure 2.2: Atomic structure of gold

Figure 2.3: Excerpt from the periodic table of elements

Figure 2.4: Good conductors

Figure 2.5: Allotropes of carbon

Figure 2.6: Electrons flowing in a conductor

Figure 2.7: Conduction

Figure 2.8: Induction

Figure 2.9: Simple electrical circuit

Figure 2.10: Soldering on a PCB

Figure 2.11: Expanding breadboards

Figure 2.12: Bottom of breadboard

Figure 2.13: Breadboard clip

Figure 2.14: Breadboard features

Figure 2.15: Binding post close-up

Figure 2.16: Power rails jumpered together

Figure 2.17: An IC in DIP format across a breadboard dip

Figure 2.18: Breadboard rows and columns

Figure 2.19: LEDs

Figure 2.20: Jumpers, wire stripper, needle-nose pliers, and safety glasses...

Figure 2.21: Completed LED circuit

Figure 2.22: LED shorted out

Figure 2.23: Ohm's law

Figure 2.24: Carbon film resistors

Figure 2.25: Resistor color code

Figure 2.26: Voltage divider

Figure 2.27: Fuses and a circuit breaker

Figure 2.28: Imprint on a fuse casing

Chapter 3

Figure 3.1: Block diagram and schematic

Figure 3.2: Conductor symbols

Figure 3.3: Common schematic symbols

Figure 3.4: Poles and throws

Figure 3.5: A sampling of switches

Figure 3.6: Schematic symbols for switches

Figure 3.7: Datasheet

Figure 3.8: What you need

Figure 3.9: Wiring diagram of simple circuit with switch

Figure 3.10: Vertical resistor

Figure 3.11: Completed circuit with switch

Figure 3.12: Schematic for simple circuit with switch

Chapter 4

Figure 4.1: Arduino Uno board

Figure 4.2: ATmega328 microcontroller

Figure 4.3: TX and RX lights and USB port

Figure 4.4: Adapter for 9V battery and a transformer

Figure 4.5: Power jack and USB port

Figure 4.6: Power connections

Figure 4.7: Digital and analog pins, LED 13, and GND

Figure 4.8: A square wave

Figure 4.9: An analog wave

Figure 4.10: Binary values across 5 volts

Figure 4.11: Arduino reset button

Figure 4.12: Default Arduino IDE screen

Figure 4.13: Renaming a sketch

Figure 4.14: Project materials

Figure 4.15: Selecting the port

Figure 4.16: A flashing LED circuit

Figure 4.17: Choosing the Blink sketch

Figure 4.18: Changed Blink sketch

Figure 4.19: Running Lights in action

Figure 4.20: A pushbutton circuit

Figure 4.21: Serial Monitor with data

Chapter 5

Figure 5.1: A typical multimeter

Figure 5.2: AC-to-DC power transformer

Figure 5.3: Testing polarity

Figure 5.4: Taking measurements

Figure 5.5: Potentiometer

Figure 5.6: Dimming via potentiometer

Figure 5.7: Simple circuit

Figure 5.8: Measuring the circuit

Figure 5.9: Measuring voltage rise

Figure 5.10: Voltmeter and Serial Monitor

Figure 5.11: Arduino ohmmeter

Figure 5.12: Arduino ohmmeter output

Figure 5.13: A shunt resistor schematic

Figure 5.14: Ammeter circuit

Figure 5.15: Ammeter output

Figure 5.16: Arduino continuity tester

Figure 5.17: Camp lamp schematic

Figure 5.18: A button circuit

Figure 5.19: Breadboard configuration, one row

Figure 5.20: Breadboard configuration, four rows

Figure 5.21: A soldering station

Figure 5.22: Clipping solder leads

Figure 5.23: Perfboards

Figure 5.24: A heat gun and shrink tubing

Chapter 6

Figure 6.1: Sample datasheet

Figure 6.2: The power wheel

Figure 6.3: Resistors

Figure 6.4: Power meters

Figure 6.5: Electric supply bill

Figure 6.6: An LCD front and back

Figure 6.7: An LCD wiring diagram

Figure 6.8: HelloWorld sketch

Figure 6.9: Multimeter and circuit

Figure 6.10: Wattmeter connections

Figure 6.11: Adding a library

Figure 6.12: Wattmeter on an LCD

Figure 6.13: A completed meter and circuit

Figure 6.14: Meter and circuit connections

Chapter 7

Figure 7.1: Series, parallel, and complex circuits

Figure 7.2: LED circuits

Figure 7.3: Incandescent lamp circuits

Figure 7.4: A parallel branch current

Figure 7.5: Kirchhoff's laws

Figure 7.6: Parallel resistances

Figure 7.7: Wire gauge

Figure 7.8: Batteries and holders

Figure 7.9: Improper battery connection

Figure 7.10: Sources in series and parallel

Figure 7.11: Aiding and opposing sources

Figure 7.12: LED series circuit calculation

Figure 7.13: Solving the complex circuit

Chapter 8

Figure 8.1: Simple polarity tester

Figure 8.2: Perfboard polarity tester

Figure 8.3: Diodes and the PN junction

Figure 8.4: An anode and a cathode

Figure 8.5: Various diodes

Figure 8.6: Common diode symbols

Figure 8.7: A Zener voltage regulator

Figure 8.8: A power diode voltage divider/regulator

Figure 8.9: A bridge rectifier

Figure 8.10: A flyback diode

Figure 8.11: Seven-segment LED wiring

Figure 8.12: A bar LED

Chapter 9

Figure 9.1: A transistor face

Figure 9.2: A transistor pinout

Figure 9.3: An amplifier circuit schematic

Figure 9.4: An amplifier circuit

Figure 9.5: An amplifier current flow

Figure 9.6: Signal and power transistors

Figure 9.7: The hierarchy of transistors

Figure 9.8: Transistor symbols

Figure 9.9: An N-channel MOSFET

Figure 9.10: A transistor and heat sink

Figure 9.11: A circuit schematic

Figure 9.12: A transistor switch circuit

Chapter 10

Figure 10.1: Inside a capacitor

Figure 10.2: Common capacitor types

Figure 10.3: Failed electrolytic capacitor

Figure 10.4: Capacitor symbols

Figure 10.5: Time delay circuit

Figure 10.6: Capacitor charged and discharging

Figure 10.7: Transient response

Figure 10.8: Astable multivibrator circuit

Figure 10.9: Inserting a switch

Figure 10.10: Capacitors in parallel

Chapter 11

Figure 11.1: Magnetic domains

Figure 11.2: Magnetic lines of flux

Figure 11.3: Wind farm

Figure 11.4: Electromagnet

Figure 11.5: Magnetism in Circuits

Figure 11.6: Homopolar motor

Figure 11.7: Inductor schematic symbols

Figure 11.8: Inductors on a motherboard

Figure 11.9: Doorbell circuit

Figure 11.10: Reed relays

Figure 11.11: Magnetic alarm

Figure 11.12: A relay

Figure 11.13: Relay oscillator circuit

Figure 11.14: Emergency lighting circuit

Chapter 12

Figure 12.1: Water alarm

Figure 12.2: Inside a buzzer

Figure 12.3: Speakers and microphones

Figure 12.4: Light-based circuit control devices

Figure 12.5: Light bulbs

Figure 12.6: Laser pointer

Figure 12.7: Night-light circuit

Figure 12.8: Electron flow in the night-light

Figure 12.9: Laser alarm circuit

Figure 12.10: Calculating analog in values

Chapter 13

Figure 13.1: Inside a 555 timer IC

Figure 13.2: Mark time, space time, and cycle

Figure 13.3: A 555 Astable timer circuit schematic

Figure 13.4: A 555 timer pinout

Figure 13.5: A 555 timer circuit

Figure 13.6: A completed astable circuit

Figure 13.7: Inverting and noninverting op-amp

Figure 13.8: Decimal, binary, and hexadecimal

Figure 13.9: Logic gates and truth tables

Figure 13.10: A logic gate pinout

Figure 13.11: An AND gate pinout and circuit

Figure 13.12: OR gate and NOT (inverter) pinouts

Figure 13.13: Logic pulser

Figure 13.14: Oscilloscope

Chapter 14

Figure 14.1: Duty cycles

Figure 14.2: Datasheet with duty cycle

Figure 14.3: PWM LED dimmer circuit schematic

Figure 14.4: PWM LED dimmer circuit pinout

Figure 14.5: PWM LED circuit complete

Figure 14.6: Complete circuit with oscilloscope

Figure 14.7: Flyback diode

Figure 14.8: Clamping Zener diodes

Figure 14.9: PWM motor circuit with flyback diode

Figure 14.10: Simple Arduino PWM circuit

Chapter 15

Figure 15.1: A homemade voltaic cell

Figure 15.2: Homemade thermocouple

Figure 15.3: Construction of a PV cell

Figure 15.4: PV cells, panels, and array

Figure 15.5: Project pinout

Figure 15.6: PV cell’s Serial Monitor output

Figure 15.7: Completed PV monitoring circuit

Figure 15.8: Inside a motor/generator

Chapter 16

Figure 16.1: Common transformers

Figure 16.2: Inside a transformer

Figure 16.3: Phase relationships

Figure 16.4: Calculating current, voltage, and turns ratios

Figure 16.5: Autotransformers, variacs, and taps

Figure 16.6: A transformer label

Figure 16.7: A 555 timer circuit

Figure 16.8: A transistor section

Figure 16.9: Completed transformer circuit

Figure 16.10: Demo circuit readings

Chapter 17

Figure 17.1: Typical PV system

Figure 17.2: A small inverter

Figure 17.3: An inverted signal circuit

Figure 17.4: Inverting current

Figure 17.5: An Arduino PWM circuit

Figure 17.6: A square wave

Figure 17.7: A single RC filter stage

Figure 17.8: Four RC filter stages

Figure 17.9: Filtered oscilloscope outputs

Figure 17.10A: Half-wave rectification

Figure 17.10B: Full-wave rectification, center tap transformer

Figure 17.10C: Full-wave rectification, bridge rectifier

Figure 17.11: Single-phase and three-phase power

Figure 17.12: Variable power supply circuit

Figure 17.13: A variable power supply

Chapter 18

Figure 18.1: The electromagnetic spectrum

Figure 18.2: A crystal radio and amplifier schematic

Figure 18.3: Amplifier circuit complete

Figure 18.4: A simplified radio transmitter

Figure 18.5: A simplified radio receiver

Figure 18.6: AM and FM waves

Figure 18.7: The TEA5767 FM radio shield

Figure 18.8: Installing a library

Figure 18.9: Finding a library

Figure 18.10: Displaying line numbers in the IDE

Figure 18.11: Radio module connections

Figure 18.12: Potentiometer station selection

Figure 18.13: Tuned circuits

Chapter 19

Figure 19.1: The Arduino Create main screen

Figure 19.2: A blue LED dimmer circuit

Figure 19.3: Your Things screen

Figure 19.4: The properties of Blue_Light

Figure 19.5: The Editor page

Figure 19.6: The

thingProperties.h

tab

Figure 19.7: The Secret tab

Figure 19.8: The ReadMe.adoc tab

Figure 19.9: The IoT Cloud thing

Figure 19.10: Welcome to Dashboards

Figure 19.11 Widgets

Figure 19.12: The widgets added screen

Figure 19.13: Linking the widget

Chapter 20

Figure 20.1: A sewable LED kit

Figure 20.2: SMD examples

Figure 20.3: The thread circuit

Figure 20.4: Separate LED boards

Figure 20.5: Threading the needle

Figure 20.6: Sewing the components

Figure 20.7: Project complete

Figure 20.8: SMT stick-on LEDs and circuits

Figure 20.9: Graphite conductors

Figure 20.10: A painted circuit

Figure 20.11: Paint over a painted circuit

Figure 20.12: A copper tape circuit

Figure 20.13: The copper tape card front

Figure 20.14: Finishing the card

Figure 20.15: The insulating square

Figure 20.16: The lit blue dough square

Figure 20.17: The lit flag

Guide

Cover

Table of Contents

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A Geek Girl’s Guide to Electronics and the Internet of Things

Audrey O’Shea

Introduction

Welcome to the world of electronics! This is an exciting place to be, and I'm so glad that you've decided to join me in this journey. IoT and electronics are inseparable, as you'll soon see. We'll start with learning about electronic components and creating some useful circuits. In addition to traditional electronic circuits on breadboards, many chapters have circuits that use the programming power of an Arduino board. Finally we'll be connecting your circuits to the Internet so you can control them from anywhere. This book starts small and helps you grow in knowledge as it progresses and encourages you to reach even further. My true hope is that it will get you excited about working with electronics, regardless of whether it's a hobby or a new career, and that it will give you confidence to do whatever it is that makes your heart sing, no matter who or where you are in life.

I'm here to tell you that virtually everyone can do electronics, you included. Although this is a male-dominated field, I encourage you not to let that deter you from getting into the game. If you're female or any other non-traditional geek, follow your passion like I did. Like me, you may be the only woman in the room, but that's perfectly fine. It's an exciting and dynamic career field, and if you're different from the stereotypical electronics geek in some way, that's great! You bring a different perspective, which makes you that much more valuable.

Who Will Benefit Most from This Book

This book is intended for beginners, or those with some basic electronics knowledge who want to fill in those knowledge gaps with tidbits of information that can make all the difference. You'll start with the basics and progress to more interesting (difficult) projects as you go along. This book contains more than 35 “Try This” projects where you can see how things work and solidify what you're learning. Some of the projects include the following:

Creating a super-bright camping light using LEDs

Building a laser trip alarm

Making paper and clay electronics for kids

Creating light-activated circuits

Constructing an Arduino wattmeter

Connecting your projects to the Internet

You'll learn some science behind how things work so the components and connections will make sense, and you'll learn how to avoid some of the pitfalls of circuit building. For example, after studying the material in this book, you'll know why you need a flyback diode for a motor (and understand what one is), instead of having to figure it out when the circuit fails and you're on your third set of components. However, I expect there may be some of that in your future, too, as you take your own ideas and build them into new and interesting circuits. Mistakes are part of the learning process. That's the fun of experimenting! You will create prototype circuits on breadboards, and if you're happy with the result, you can solder them onto something more permanent because you'll know how to do that, too.

Sourcing Parts and Supplemental Materials

I wouldn't want to teach you to fly and then leave you on your own, so throughout the book I've included some of my favorite places to find information and components.

My website, cliffjumpertek.com, also has additional reference materials, tutorials, and videos of the book's projects to help with your journey, should you need it.

Special Features

TIP Throughout the book, you'll find tips that will provide you with supplemental information, usually to make something easier so you don't have to learn from trial and error.

WARNING Included in this book are warnings—please take these seriously! Make sure you read all of these because they have information to protect you or others from injury and/or your project from damage.

NOTE Notes are supplemental material or interesting tidbits of information.

Time to turn the page and get started on your future in electronics! I'll see you there.

What Does This Book Cover?

This book is designed to provide you with a foundation of knowledge in electronics, IoT, and the Arduino environment. Its multitude of projects are the springboard to a deeper understanding and ever more challenging projects.

Chapter 1

: IoT and Electronics

The book starts with an explanation of how electronic circuit boards fit into the world of IoT. The components of an IoT system are explained, showing how IoT starts with electronic sensors and then interfaces with computers and communication systems. It also notes some of the challenges in developing and using IoT systems, as well as where IoT may be headed in the future.

Chapter 2

: Electricity: Its Good and Bad Behavior

 Understanding how electricity behaves will help you to determine why circuits are or are not working. This chapter delves into the science behind electricity. It also explains electricity's characteristics and the relationship between those electrical characteristics. You'll learn how to build a simple circuit and then how to create a circuit on a breadboard, which is the foundation for most of the circuits created in the rest of the book.

Chapter 3

: Symbols and Diagrams

 The field of electronics uses symbols to represent components when communicating information. This chapter teaches the basic symbology used and how to create a breadboard circuit using a schematic as a guide.

Chapter 4

: Introduction to the Arduino Uno

 The Arduino is a popular platform for creating IoT implementations. In this chapter, you'll learn the form and function of the Arduino Uno and its programming platform. You'll also learn about analog and digital signals and the role of binary, all while building projects.

Chapter 5

: Dim the Lights

 This chapter gets its name from one of the eight labs included in it; however, it's more about measuring electricity. You'll learn to use a multimeter and create a voltmeter, ohmmeter, and ammeter using an Arduino board. There's also a great project for creating a camp lamp, and it finishes with a lesson on soldering, perfboards, and shrink tubing, so you'll know how to put those projects together on a more permanent basis.

Chapter 6

: Feel the Power

 Power is another characteristic of an electrical circuit and is explained in this chapter. You'll learn the relationship between Ohm's law and Watt's law as well as power from batteries, power ratings of resistors, and ways to measure circuit power. You'll also learn how to use an LCD screen with an Arduino board.

Chapter 7

: Series and Parallel Circuits

 Electricity behaves differently depending on the path that it takes through a circuit. This chapter explains the implications of letting it take those different paths. You'll also learn about the effect of wire size and composition. In the spirit of full disclosure, this chapter involves math.

Chapter 8

: Diodes: The One-Way Street Sign

 This is the first of several chapters about specific electronic components. You'll learn about diode construction and why diodes behave as they do, along with some common uses for diodes. The projects show you how to work with seven-segment LEDs and bar LEDs.

Chapter 9

: Transistors

 You may know that transistors are the foundation of our modern computer processors, but they can do so much more. This chapter explains different types of transistors and their uses while giving you some practice working with them.

Chapter 10

: Capacitors

 Another powerhouse when it comes to computer circuits is the lowly capacitor. They're found everywhere and sometimes taken for granted. This chapter teaches you the characteristics of capacitors and gives you some experience putting them to work.

Chapter 11

: The Magic of Magnetism

 Magnetism and electricity are like two sides of a coin. This chapter examines that relationship and how magnetism is put to serious work. You'll also learn about relays, which are a component of many industrial electronic circuits.

Chapter 12

: Electricity's Changing Forms

 Working with electricity is even more fun when you can change it into light and heat and sound, or vice versa. This chapter shows you several ways to do just that, along with the science behind the changes.

Chapter 13

: Integrated Circuits and Digital Logic

 Integrated circuits make our work easier by having an entire circuit on a chip the size of your thumbnail, or even smaller, while digital logic chips can be the decision-makers on our circuits. This chapter explores both and introduces the oscilloscope, which lets you see in real time what is happening electrically in a circuit.

Chapter 14

: Pulse Width Modulation

 Pulse width modulation (PWM) enables a digital signal to control an analog device, such as a motor. In this chapter, you'll build a PWM circuit on a breadboard and then learn how to accomplish the same magic using an Arduino board.

Chapter 15

: Sources of Electricity

 Sources of electricity are touched upon in other chapters, but this one brings all the pieces together in one place. Here you can practice making some electrical current of your own and build an Arduino circuit to monitor the output of a photovoltaic cell.

Chapter 16

: Transformers and Power Distribution

 Transformers are used to change the electrical properties of a circuit and play a big role in power supplies and power distribution. This chapter examines the types and roles of transformers. It also explains how they accomplish changing electrical properties and gives you some experience working with one.

Chapter 17

: Inverters and Rectifiers

 Many times a circuit needs to be converted from DC to AC or AC to DC. The devices that perform that task are called inverters and rectifiers, respectively. In this chapter, you'll learn how both work and how to filter circuits for a more desirable and consistent output. You'll even build a small variable power supply.

Chapter 18

: Radio Waves and Tuned Circuits

 Radio waves are the communication vehicles of our cell phone networks, local area networks, and free music stations. Their use grows every day, so knowing how they work is important whether you're working with computers or IoT devices. This chapter explains AM and FM and introduces working with an Arduino shield to create a radio.

Chapter 19

: Connecting Your Circuits to the Cloud

 Being able to control devices remotely is an important aspect of many IoT implementations. This chapter teaches you how to do just that using a Wi-Fi enabled Arduino board and the Arduino IoT cloud.

Chapter 20

: Just for Fun

 While working with electronics is always fun, most of the time electronic circuits are created for serious work. This chapter explores some of the not-so-serious uses of electricity. If you're the least bit creative, and I'm sure you are, then this chapter is for you!

Part IIoT and Electricity Basics

In This Part

Chapter 1

: IoT and Electronics

Chapter 2

: Electricity: Its Good and Bad Behavior

Chapter 3

: Symbols and Diagrams

Chapter 4

: Introduction to the Arduino Uno

Chapter 5

: Dim the Lights

Chapter 6

: Feel the Power

Chapter 7

: Series and Parallel Circuits

CHAPTER 1IoT and Electronics

“Toto, I have a feeling we're not in Kansas anymore.”

—Dorothy, The Wizard of Oz

Sci-fi movies and shows have always been my obsession. As a child, I would watch in awe when reruns of The Jetsons showed people talking on video phones, the almost-human robot maid, and sidewalks that moved. Then there were the Star Trek reruns where characters walked around with communicators that allowed them to talk to anyone just by tapping them. Later, Star Wars had language translators that would automatically translate into any other language … rather like what Google Translator does now.

Forty or fifty years ago, many devices and capabilities that are commonplace now were considered ridiculous, impossible, or mere fantasy. Were these movies and TV shows predictions of the future, or did they help to shape the future by putting these notions of “impossible” devices into someone's mind to start working on? Either way, many of those devices exist now for us in some form or another. Even 20 years ago, most people still depended on their home phones for communication. Do you know anyone who still has a landline at home? They are few and far between.

The Electronics Technicians Association was founded in 1978 as the electronics industry was beginning to grow slowly. Now, it's growing by leaps and bounds on a daily basis. It's astonishing how far electronics have come in such a relatively short time when compared to human existence, and it's even more incredible when we ponder how far we will be 50 years from now. Many of the technological advances of the future will be here due to artificial intelligence, machine learning, and the myriad of sensors starting to cover our world. The world is about to take another leap forward, and if you want to be part of that journey, learning electronics is the place to start. As so many maps show us … “You Are Here.”

IoT in a Nutshell

What is IoT? As you may know, IoT stands for “Internet of Things.” IoT refers to a vast array of connected devices that gather and transmit data over interconnected networks with or without human intervention, sometimes even responding to the captured data automatically as machines talk to machines and learn from each other. (When IoT involves manufacturing processes, it is often called industrial IoT [IIoT].) IoT can include data gathered by proximity sensors on your car's front that detect deer in the roadway and signal your brakes to immediately slow down the car without you doing anything. It also includes when moisture levels (or lack thereof) are transmitted from a field to that field's watering system, signaling to turn on the irrigation system without a human lifting a finger. Even a dog's GPS-enabled location device is part of an IoT system, as is the Tile that I press to locate my often-misplaced car keys.

Other systems considered part of IoT are smart cities, smart grids, smart homes, smart watches, and manufacturing machines talking to and learning from each other. Smart devices are used in hospitals, schools, retail, and nearly any other service or business you can think of. Last year, I attended a virtual meeting with someone from a major networking device company. He was speaking from his office about power over Ethernet and how the interconnected devices controlling heat, lighting, air quality, etc., all ran automatically in the high-rise office building he was in. I noticed a model of a pig on the credenza behind him and asked about it. Yes, it was a pig wearing an IoT collar.

What does this have to do with learning electronics? Everything! Electronic sensors and circuits are the beating heart of an IoT system.

Parts of an IoT System

What comprises an IoT system changes depending on who you ask, but regardless of what particular twist an industry or company may put on it, certain things must be there. For an overview of an IoT system, see Figure 1.1.

Devices

What is an IoT device? IoT devices include sensors, circuits, software, actuators (things that do something, such as switch from one state to another), and microprocessors, all rolled into a neat little package. These devices also need a way to communicate and send data to a place where it will be processed, manipulated, and action taken based on the data, or they need to be able to communicate to receive instructions based on the data that was gathered by some other device. Therefore, an IoT device can be on either the sending end or the receiving end, or possibly both.

Figure 1.1: An IoT system

Take, for example, a smart home with a remote-controlled thermostat, which has a few layers of things going on. First, the thermostat is a device. It has a sensor that measures the temperature and sends that information to a circuit board with a microprocessor where the reading is converted into data, which is manipulated. If certain conditions within the software program are met, the microprocessor sends a command to another component, telling it to turn the furnace either off or on. This example is machine to machine but involves sensors, circuits, software, microprocessors, communication, and actuators.

Another function of this device would be the ability to access the device from a cell phone via the Internet and Wi-Fi to tell the device to turn up the heat before the user gets home. This example involves a user interface, which is part of the entire user experience, but here we have the cell phone acting as a device and the thermostat acting as another device, communicating via the Internet.

Sensors

The first part of any IoT system is a device that senses something physical, whether a particular condition or event. It could be a fiber optic cable in a building's concrete that picks up a pressure change, or it could be a proximity sensor, heat sensor, humidity sensor, optical sensor (ambient light, IR, UV), gas sensor, position sensor, magnetic sensor, motion sensor (accelerometer, gyroscope), color sensor (light again), or touch sensor (pressure). A search for sensors on an electronics components site at the time of this writing yielded tens of thousands of results.

As mentioned in the preceding section, a sensor receives some form of raw data and passes it on to a circuit and most likely a microprocessor, where the data received is interpreted. Take, for example, a temperature. The sensor doesn't send “temperature” to the circuit. Instead, a change in the temperature causes a rise or fall in either current or voltage through the device, which is passed to a circuit where it is read and interpreted according to instructions, known as software, controlling what the microprocessor tells the circuit to do. In future chapters, you'll learn how to work with some of these sensors and what the technology is that drives them.

Choosing the right sensor is an important first step, and several characteristics need to be considered.

What's being measured:

Temperature, light, pressure, etc.

Electrical:

Current, voltage, and power limitations.

Physical:

How much pressure, heat, light, etc., can it endure and remain viable?

Accuracy:

How far might it vary from the actual measurement?

Sensitivity:

How much does the input need to change before the output changes?

Reliability:

What is the track record of this sensor? When does it stop being accurate? How often does it break down?

Range:

What are the minimum and maximum values that can be measured?

Circuits, Software, and Microprocessors

Once the right sensor is found, the circuitry and software can be designed to interpret the information that is provided by the sensor. A myriad of choices exists for all of these. A microprocessor can be a single chip designed to perform logic or a microprocessor platform, such as an Arduino device. The choice of processor may determine the choice of software that is used.

Communication

Because the “I” in IoT stands for Internet, the assumption can be made that the device is expected to be interconnected in some way either through a local area network (LAN) or through the Internet. However, different levels and aspects of communication may be used by IoT devices.

Levels

A device may communicate with other devices, such as a moisture sensor in a field that triggers a watering system to work, or devices in a factory assembly line that communicate with other devices to either slow down or speed up the processes based on conditions. This is machine-to-machine communication. Systems like these may even use machine learning, which is a process where computers use algorithms to look for related data and learn, changing their programming based on data without human intervention. Machine learning is far too complicated to explain here but definitely an emerging technology worth paying attention to.

In the automatic watering system example, the devices may be connected only to a LAN, but most likely they will be gathering data and sending it, via one or more protocols and networks, to a place where it is processed.

Protocols and Standards

Protocols are essentially rules for communication, and they are the topic of much learning and discussion in the computer world. Standards typically define how a network is built and what protocols are used on it. Networking standards are needed to ensure that different devices, possibly from different vendors or manufacturers, are all able to communicate effectively. Knowing what type of communication is needed and used by each part of an IoT system is an important consideration. Any of the following standards might be part of an IoT system:

Ethernet:

Wired LAN networking standard

Bluetooth:

Short-range wireless, usually connecting mobile devices

Wi-Fi:

Wireless networking standard allowing wireless networks to connect to a wired system or each other

Cellular:

For longer-range wireless connectivity via the cellular system

Each of these standards may have multiple protocols that are used with that particular standard, and any of them may allow a device to connect to the Internet. Often more than one will be used. In the case of the smart thermostat, it may use Wi-Fi to connect to a local LAN using Ethernet, which is connected to the Internet via some other method, such as a cable modem, fiber optics, or satellite. The remote user may be connecting their cell phone to the thermostat via Wi-Fi or the cellular network. All of these standards need to work in harmony for successful communications across an IoT system.

Data Analytics and Management

Data analytics is the growing field of sorting and analyzing raw data to derive meaningful and actionable information from it. It is the stuff of algorithms and perhaps insight gained from the experience of working with data. Four basic types of data analysis exist.

Descriptive

Diagnostic

Predictive

Prescriptive

Descriptive analytics identifies what has happened based on data. It is often based on key performance indicators (KPIs). For example, did sales go up or down and by how much or what percentage? Did the field have to be watered more often or less often?

Diagnostic analytics attempts to explain why the changes occurred. It can look at data outliers and what was occurring when the change in data occurred.

Once the what and why are known, predictive data analysis models can be built to anticipate problems before they happen or identify future trends.

Finally, prescriptive data analysis gives the user a course of action to take to avoid the problems identified in predictive models or to take full advantage of what's around the corner.

Data is more valuable than the hardware and software used to mine it from various sources, so managing that data is a primary concern for any business. The field of data management is concerned with collecting data, maintaining its physical security, securing the privacy of any personally identifiable information (PII), and preserving that data in a cost-effective and efficient manner. Data analytics is part of data management, and the way this data is used can cause a business to flourish or fail.

The User Experience

The user experience refers to every place that the user and the IoT system come into contact with each other. If, for example, an employee is tasked with identifying a problem quickly and accurately, then the interface that the employee uses needs to have the right information in an application that is easy to use, and it needs to be updated in a timely manner.

Depending on the situation or business, the user experience can also include interacting with customer service or other personnel, how easy the phone system is to use, etc.

Challenges in Implementing IoT

Implementing technology is not without challenges, particularly in an IoT system. One of the biggest challenges for remote IoT devices is power. Running electrical wires is not always practical, and batteries have a limit to their capacity, so creating a system that runs on as little power as possible, or perhaps renewables like solar power, is a significant hurdle to overcome in developing an IoT solution.

Another major concern is the security and ownership of data. If data is stored by a provider, who owns and has access to the data? What encryption will be used to transmit the data from where it's gathered to where it's used? These are questions that any businessperson would want to know before implementing a system. Determining the right data to gather is probably the first question to answer, because measuring the wrong facts won't help a business make the right decisions.

Perhaps the biggest challenge of all is cohesiveness. If a system is cohesive, then it works together smoothly, which can be a problem when so many different systems are involved. Beginning with the sensors that detect data, through the circuitry and networks that transfer and store the data, then send the data to a user's interface on a device such as a phone or computer, and back again as the user responds through a local network to the web and then to the actuator; during this process, there needs to be a seamless way to transmit and manipulate the data. With so many protocols and systems involved, that can be difficult indeed. Developing a system needs to start with a bird's-eye view of the major parts, working down to the component level to ensure that all of the system's parts work together to move data around smoothly.

IoT into the Future

IoT and IIoT will not be going away in the foreseeable future. In fact, they will continue to grow as processes and machines get smarter and people find more uses for IoT. What may have started as a curiosity, with devices that were more fun than function in the hands of a few hackers, is now a major industry and will be causing paradigm shifts in virtually all industries and businesses.

Devices and sensors will continue to get smaller, get less expensive, and work better. We will learn how to better harvest the data from IoT devices and put them to more and more uses. Already billions of IoT devices are being used, and the number increases exponentially as every day forward-thinking inventors and electronics enthusiasts devise more uses for the technology. Where will you fit into this growing industry? Perhaps the best place to start is with a basic understanding of electronics, and to that end, read on.

CHAPTER 2Electricity: Its Good and Bad Behavior

“Never trust an atom. They make up everything.”

Unknown

You probably already have an idea of how electricity behaves. If you turn on a light switch, electricity is converted to light. It makes motors run and can be created by a generator to charge our cell phones when the power is out. You also know that it's a bad idea to stand outside in a lightning storm because it's likely also raining, and if you're wet and the tallest thing around, you're practically inviting lightning to strike you. Electricity can keep us alive if it's powering our heart, and it can kill us if we don't respect it. What you may not understand is why electricity behaves the way it does, which is what this chapter is about. If you're going to be the next Bill Gates or Steve Jobs and invent something that will alter life as we know it, you'll need to start with a basic understanding of how and why electricity behaves the way it does.

First, a little static electricity lab.

Try This: Creating Some Static

This lab is just for fun. Most grade-school kids have rubbed a balloon on their head or combed their hair with a plastic comb and seen the magic that is static electricity. What happens is that the energy of friction pulls electrons from the atoms of the hair onto the comb or balloon, giving it a negative charge and the hair a positive charge. The negatively charged balloon attracts the more positively charged hair. (Opposites attract.) If two balloons are negatively charged, they will push away from each other. (Like charges repel.) You can also do other fun things with static. The following sections contain a few for your amusement.

For these projects, you need the following materials:

Fur, wool cloth, or hair (a source of electrons)

PVC pipe about 2′ long

Styrofoam plates

Water faucet

Balloon

Fluorescent tube

Water glass or glass vase

Styrofoam ball

Aluminum foil

String

Levitate a Styrofoam Plate

Rub a Styrofoam plate with a wool cloth to charge it and then set it on a flat surface.

Rub a second Styrofoam plate to charge it as well.

Try to put the two plates together. If they push away from each other, you know they're both negatively charged. Now, put your hand a few inches above the plate that's on the table and try to place the other plate on top of the first one. It should float up to your neutral (no charge) hand. It is being pulled by your hand and pushed by the other plate.

Bend Water

Negatively charge the PVC pipe by rubbing it with the fur or wool cloth.

Turn a water faucet on so that it is running a small steady stream.

Move the charged PVC pipe near but not touching the water. You should see the water bend toward the more negatively charged PVC pipe (

Figure 2.1

).

Creating Light with Static

Negatively charge the balloon by rubbing it with the wool cloth, hair, or fur.

Enter a darkened room.

Touch the balloon to the two electrodes sticking out of the fluorescent tube. The tube completes the circuit and inside the tube the electrons excite the gasses and cause the glow.

Figure 2.1: Bending water

The static electricity generated this way will have enough voltage but not enough current to light a light-emitting diode (LED), which we'll talk about later. It does have enough voltage to excite the electrons of the gasses in the fluorescent tube. The process is similar to someone walking across a carpet and then touching a metal doorknob. They may get quite a shock when the negatively charged electrons jump to the more positively charged doorknob. The electrons move quickly and may cause sound or a flash of light and be thousands of volts but not a lot of current. Current and voltage will be explained soon.

Magically Move a Styrofoam Ball

Wrap a small Styrofoam ball with aluminum foil.

Tie a string around the ball.

Tape the end of the string to the inside bottom of the water glass or glass vase, making sure that the ball will hang freely when the glass is turned upside down.

Turn the glass upside down.

Charge the PVC pipe and bring it toward the glass. The ball is attracted to the negatively charged PVC pipe.

While these were fun demonstrations of static electricity and the law of charges (like charges repel each other, opposite charges attract), static electricity does have some serious industrial uses. Static electricity is responsible for transporting toner inside a printer from the negative toner container to the more positive (but still negative) drum and finally onto the positively charged paper. Static is also used in some pollution control systems where particles are charged and then attracted to plates with the opposite charge, reducing pollution. Static is also used in applying paint to cars. What causes those charges? Read on.

Electricity at an Atomic Level

What is electricity? To understand it, you need to look at atomic structure. Figure 2.2 shows a two-dimensional drawing of a three-dimensional object, an atom. To be specific, it is the structure of a gold atom. Atoms are the building blocks of everything, including human beings. At the center of the atom is the nucleus, which contains particles called protons and neutrons. Orbiting around the nucleus is a cloud of particles called electrons. Electrons are located in orbitals and shells at various distances from the nucleus in the center depending on the energy they exhibit at the moment. A gold atom has 79 protons, 79 electrons, and 118 neutrons.

Figure 2.2: Atomic structure of gold

Matter that is made of only one type of atom is called an element. These elements and the information about each can be found on the periodic table of elements (Figure 2.3). While there are 94 naturally occurring elements, more have been created by humans. Each element is assigned an atomic number, which is equal to the number of protons in the nucleus of the atom, so our gold atom's atomic number is 79.

Protons have a positive charge, neutrons have no charge, and electrons have a negative charge. Atoms seek to be in balance, so when they are at a ground state, atoms always have the same number of protons and electrons, making the atom have a net neutral (no) charge. When an atom is acted upon by some outside force such as friction, it can lose or gain electrons. This process of losing and gaining electrons is called ionization. Because electrons are negative, if the atom loses an electron, it becomes a positive ion. It will have more positively charged particles (protons) than negatively charged particles (electrons) and therefore a net positive charge. If an atom gains an electron, it becomes a negative ion because there are more negatively charged particles (electrons) than positively charged particles (protons).

Figure 2.3: Excerpt from the periodic table of elements

NOTE The designations of positive and negative were chosen by Benjamin Franklin as a way to explain his observations of electrical behavior.

The law of charges tells us that opposites attract, so the positively charged protons are always pulling on (attracting) the negatively charged electrons. When ionization occurs, the electrons the atom loses (or gains) will be located in the outermost shell, which is called the valence shell. If an electron in a lower shell is acted upon by some outside energy, such as heat or light, it can jump to a higher shell. When it loses its energy, it falls back down toward the nucleus. Only a certain number of electrons can exist in a given shell, but right now we don't need to explore that any further.

What does this have to do with electricity? Everything! What we know as electricity is the movement of those electrons from atom to atom in the same general direction, as they're trying to balance atoms in a chain reaction.

Conductors and Insulators

Certain elements will easily give up their valence electrons. We call those elements good conductors. Examples of good conductors are gold, aluminum, copper, silver, and mercury. Each of these conductors has characteristics that make them better than the others in certain situations. For example, silver is the best conductor, but gold is often used for connections on computer boards because of its tendency to avoid corrosion. Mercury is a liquid that has been used in devices such as thermostats, thermometers, and motion switches, and for measuring pressure. However, because it has been identified as a pollutant, the electrical and electronics industries have been working to replace mercury in electrical and electronic devices. Despite their efforts, many devices containing mercury still exist. Copper is used in household wiring because it is less expensive. Aluminum is used in buildings, too, but it is less conductive than copper and weighs much less, so it is useful where a lighter-weight material is needed. Copper and aluminum also have different thermal characteristics, which leads builders to choose one over the other in certain situations. Notice that silver has only one electron in its valence band. So do copper and gold, while mercury has two valence electrons and aluminum has three. While there are many other good conductors, these are the ones most often used in electrical circuits (Figure 2.4).

Figure 2.4: Good conductors

Materials that are good insulators are glass, plastic, rubber, and dry wood. Insulators do not readily give up electrons, and most are compounds, meaning that they are made from more than one type of atom. Rubber, for example, has the chemical composition C5H8, which is five atoms of carbon and eight atoms of hydrogen. Glass is made from silicon and oxygen. Other materials, such as boron and cobalt, are added to glass to change its properties. Boron, chlorine, and sulfur are elements that are considered insulators. Sulfur has six valence electrons and chlorine has seven, while boron has only three.

Silicon and germanium are semiconductors. In pure form, they are not good conductors or insulators. Yet, when their properties are changed by doping them with other chemicals, they become useful. Both are used in electronic circuits. Some diodes, which are explained in Chapter 8, “Diodes: The One-Way Street Sign,” are made of germanium, while silicon is the building material of integrated circuit chips. Silicon and germanium both have four valence electrons.

A single element can exist in different forms called allotropes. Allotropes of the same atom may behave differently. For example, carbon in the form of graphite is a conductor, but when compressed over time into a diamond, it acts as an insulator (see Figure 2.5). When in doubt, do your research to confirm a material's properties before you use it in your circuits.

Figure 2.5: Allotropes of carbon

Human beings, by the way, can be good conductors. Our skin is a decent insulator, so very low voltages are safe to handle. However, higher voltages, such as the 120VAC found in U.S. household wiring, can prove fatal or at the least provide an uncomfortable shock. Wet or sweat-soaked skin becomes more conductive, so be sure to use caution when working with electricity.

Characteristics of Electricity

Electricity has certain characteristics that you must understand to determine if the circuit you want to build will work. The first three characteristics to be aware of are current, voltage, and resistance. Current, voltage, and resistance must